BRITISH STANDARD
BS767ll.2018
Requirements for Electrical Installations
IET Wiring Regulations Eighteenth Edition
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Publication nformation I
Published by the lnstitution of Engineering and Technology. London, United Kingdom in agreement with BSL
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British Standards Institution is the independent national body responsible for preparing British view on standards in Europe and at the intemational level. rt is
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2008. 201 1, 20i3, 20i5, 2018 the Institution ofEngineering and Technology and BSI
This British Standard was published under the joint authority of the IET and of the Standards Policy and Strategy Committee on 1 July 2018.
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[email protected]). The IET, Six Hills Way, Stevenage, SG1 2AY United Kingdom.
IET Standards & Compliance staff as at June 20 1 8 JPEL164
Joint IET/BSI Technical Committee Electrical Installations
C D Cronshau CEng FIET
JPEL164,A
Verification
Eur Ing Leon Markwell MSc, BSc(Hons), CEng. MIET. MCIBSE, LCGI
JPEL.64iB
Thennal Effects
Eur Ing Leon Marku,ell MSc, BSc(Hons). CEng, MIET, MCIBSE, LCGI
JPELr64/C
Shock Protection
S G Devine
JPEL/64rD
Extemal lnfluences
M Coles BEng(Hons) MIET
MIET
G Gundry MIET
Associate secretary to al1 subcommittees
ISBN 978-1 -7 8561 -17 0-4 (paperback) ISBN 978-l-7 8561-17
l-l
(electronic)
Proofread by P E Donnachie BSc CEng FIE,T and Gary Gundr,v MIET
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CONTENTS -":. -.'..- ::
3S 1671 :20T8
4
1 :-r:-:R 11 :-:P_ER 12
SCOPE
15
OBJECTAND EFFECTS
17
.-APTER13
FUNDAI\,IENTALPRINCIPLES
2 PART 3
17
DEFINITIONS
24
PART
PART
31 32
CHAPTER CHAPTER
SCOPE. OBJECTAND FUNDAMENTAL PRINCIPLES
't4
ASSESSMENT OF GENERAL CHARACTERISTICS
44
PURPOSES, SUPPLIESAND STRUCTURE
45
CLASSIFICATION OF EXTERNAL INFLUENCES
5o
COI\4PATIBILITY
5'1
CHAPTER
[4AINTAINABILITY
51
CHAPTER
SAFETY SERVICES
52
CHAPTER33
34 35 CIAPTER 36 PART 4 a-::-:R;' l-::-:R tr2 ^- : =-: R :3 :_::_:R i4 :_::_=R.16 PART
5
52 53 3..IAPTER 54 ]-,IAPTER 55 :.IAPTER 56 PART 6 ]HAPTER 61 CHAPTER 62 CHAPTER 63 CHAPTER 64 CHAPTER 65 PART 7 ]TAPTER 3IAPTER
SECT]ON
7OO
SECT]ON
701 702 703 704 705 706 708
SECTION SECTION SECTION SECTION SECTION
709 SECTION 710 SECTION 711 SECTION 712 SECTION 714 SECTION 715 SECTION 717 SECTJON 721 SECTION 722 SECTION 729 SECTION 730 SECTION 740 SECT ON
SECTION
52
PROTECTION FOR SAFETY
53
PROTECTION AGAINST ELECTRIC SHOCK
55
PROTECTION AGAINSTTHERMAL EFFECTS
79
PROTECTION AGAINST OVERCURRENT
86
PROTECTIONAGAINSTVOLTAGE DISTURBANCESAND ELECTROI\IAGNETIC ISOLATIONAND SW]TCHING
DISTURBANCES
753
95 121
SELECTION AND ERECTION OF EQUIPMENT
--.;TER 51
SECTION
CONTINUITY OF SERVICE
124
COI\,lI\,4ON RULES
SELECTION AND ERECTION OF WIRING SYSTEMS
136
PROTECT1ON, ISOLAIION, SWITCHING. CONTROL AND I\,4ONITORING
152
EARTHING ARRANGEI!1ENTS AND PROTECTIVE CONDUCTORS
193
OTHER EOUIPIVENT
244
SAFETY SERVICES INSPECTION AND TESTING
228
NOT USED
229
NOT USED
229
NOT USED
229
INITIAL VERIFICATION
230
PERIODIC INSPECTION AND TESTING SPECIAL INSTALLATIONS OR LOCATIONS
239
GENERAL
239
LOCATIONS CONTAINING A BATH OR SHOWER SWII\,4I\,4ING POOLS
240
AND OTHER BASINS
245
ROOMSAND CABINS CONTAINING SAUNAHEAIERS CONSTRUCT]ON AND DEI\,4OLITION SITE INSTALLATIONS
256
AGRICULTURAL AND HORTICULTURAL PREI\,4ISES
258
CONDUCTING LOCATIONS WITH RESTRICTED I\,4OVEI\IENT
263
ELECTRICAL INSTALLATIONS IN CARAVAN / CAI\,4PING PARKS AND SII\,1ILAR LOCATIONS
265
I\,4ARINAS
AND SIIVILAR LOCATIONS
270
]\4EDICAL LOCATIONS EXHIBITIONS. SHOWS AND STANDS
SOLAR PHOTOVOLTAIC (PV) POWERSUPPLY SYSTEIVS OUTDOOR LIGHTING INSTALLATIONS
288
293
EXTRA-LOWVOLTAGELIGHTING INSTALLATIONS I\,1OBILE OR TRANSPORTABLE
UNITS
298
ELECTR]CAL INSTALLATIONS IN CARAVANSAND IVOTOR CARAVANS
306
ELECTRIC VEHICLE CHARGING INSTALLATJONS
316
OPERATING AND ]!lAINTENANCE GANGWAYS
320
ONSHORE UN]TS OF ELECTRICAL SHORE CONNECTIONS FOR INLAND NAVIGATION VESSELS TEI\4PORARY ELECTRICAL ]NSTALLATIONS FOR STRUCTURES. AI\,4USEMENT DEVICESAND BOOTHSAT FAIRGROUNDS AI\,4USEMENT PARKS AND CIRCUSES
325
HEATING CABLESAND EIVBEDDED HEATING SYSTEfulS
335
APPENDICES
339
1
(Normaiive)
BRITISH STANDARDS TO WHTCH REFERENCE tS |\,4ADE tN THtS STANDARD
ua
2
(lnformative)
STATUTORY REGULATIONS AND ASSOCTATED t\,4EMORANDA
359
3 (INfOTMAIiVE) TII\,4E/CURRENT CHARACTERiSTICS OF OVERCURRENT
(lnformatve) 5 (lnformatlve) 6 (lnformatlve) 7 (lnformative) 4
CURRENT-CARRYING
PROTECTIVE DEVICES AND RCDS
362
CAPACTTYAND VOLTAGE DROp FOR CABLES
CLASSIFICATION OF EXTERNAL TNFLUENCES
445
IVODEL FORI\.4S FOR CERTtFtCAT|ON AND REPORTtNG
461
HARI\,4ONlZED CABLE CORE COLOURS
484
8 (INfOTMAIiVE) CURRENT-CARRYING
CAPACITY AND VOLTAGE DROP FOR BUSBAR TRUNKiNG AND POWERTRACK SYSTEI\,4S
487
(lnformative) 10 (lnformative)
DEFINITIONS
PROTECTION OF CONDUCTORS tN PARALLELAGATNST OVERCURRENT
497
11
NOT USED
501
12
NOT USED
501
(lnformative) 14 (lnformatlve) 15 (lnformative) 16 (lnformative) 17({nformative)
l\4ETHODS FOR l\,4EASURtNG THE TNSULATTON ...
502
9
13
-
MULTIPLE SOURCE, DC AND OTHER SYSTEt\,4S
489
DETERI\,4lNAT|ON OF PROSPECTIVE FAULT CURRENT RING AND RADIAL FINAL CIRCUIT ARRANGET\,4ENTS,
504 REGULATTON 433
1
505
DEVICES FOR PROTECTION AGAINST OVERVOLTAGE
507
ENERGYEFFICIENCY
513
TABLE OF FIGURES
518
TABLE OF TABLES
522
INDEX
525
Foreword This British Standard is published under the direction ol the British Electrotechnical Cornmittee (BEC) and the Institution of Engineering and Technology (IET). Following a full review, this Standard replaced the 17th EdrtLtn of the IEE Wiring Regr.rlations BS 7671:2008 as amended. Copyright is held jointly by the IET and BSI. Technical authority lor this Standard is vested in the .loint IET BSI Technical Comn.rittee IPEL164. This Joint Technical Committee, which is responsible for the work pr.'r rously undertaken b1, the IEE Wiring Reguiations Committee and the BSI Technical Committee PEL164. meets the constitutional and operational requirements of both parent bodies. JPEL164 has the responsibility for the contenl t f thrs British Standald under the joint authority of the
IET and the BSI Standards Board.
All references in this text to the Wiring Regulations or the Regulation(s), where not otlieru,'ise specifically identified, shall be taken to refer to BS 7671 :2018 Requirements lor E lectrical Installations. Additions or alterations to the regulations owing to the issue of BS 7671:2018 ale rndicated by a side bar in the margin.
lntroduction to BS 7671 .2018 BS 7671 :2018 Requirements for Electrical Installations u'as issued on 1st Julr l0l 8 and is intended to come into effect on lst January 2019. Installations designed aftei 31st December 2018 are to comply with BS 7671:2018. The Regulations apply to the design, erection and verification oi electrical installations. also additions and alterations
to existing installations. Existing installations that have been installed in accordance with earlier editions of
the
Regulations may not comply with this edition in every respect. This does not necessarily mean that they are unsafe for continued use or require upgrading.
A summary of the main changes is given below.
NOTE: Part
This is not an exhaustive list.
1 Scope, object and fundamental principles
Regulation 133.1.3 (Selection of equipment) has been modified and now requrres cer-tain usage of equipment to be recorded on the appropriate electrical cerlification specified in Parr 6.
Part 2 Definitions Definitions have been expanded and modified.
Chapter 41 Protection against electric shock Section 41 1 contains a number of significant changes. Some of the main ones are lrentioned below.
Metallic pipes entering the building having an insulating section at their point of entn need not be connected to the protective equipotential bonding (Regulation 411.3.1.2). The maximum disconnection times stated in Table 41.1 nou.apply to final circtiits lated up to 63 Awitir one or more socket-outlets and final circuits rated up to 32 A supplying only flxed connected current-using equipment (Regulation 411.3.2.2). Regulation 411.3.3 has been revised and now applies to socket-outlets riith a rated current not exceeding 32 A. There is an exception to omit RCD protection where. other than for a du ellins. a documented risk assessment determines that RCD protection is not necessary.
A
ne'"v Regulation 411 .3.4 requires that, within domestrc {household) prer.nises. additional protection by an RCD with a rated residual operating curent not exceedinS -10 rlA shall be plor ided for AC final circuits supplying
luminaires. Regulation
411
.4.3 has an addition that states that no sri'itching or isolatrng der,ice shall be inserled in a PEN
conductor.
Regulations
411
.4.4 and 41 1.4.5 have been redrafted.
The regulations concerning IT systems (411.6) l.iare Lreen reorganized. Regulations 411.6.3.1 and411.6.3.2 have been deleted and 4l 1 .6.4 redrafted and a neu. Reculalirrl
A
.11
1.6.5 inserted.
t
-. i '
P.3:,il.irtrr lrrr.rF ligrhas been Lnsened u.here autornatic disconnection according to Regulation 411.3.2
. .;-::,r-r'. such as r'i-clrtrnic C'hapter
-12
equipr11E111
is
ri'rth limited short-ctrcuit current.
Protection against thermal effects
- :--:'.'' Regtiiation
-12 L 1 .7 has been introduced recommending the installation of arc fault detection devices (AFDDs) r:tlil gate the risk of fire in AC final circuits of a fixed installation due to the effects of arc fault culrents.
:
R.e_iiilation +ll.l.1 has been redrafted. Reference to conditions BD2, BD3 and BD4 has been deleted. Anote has reen added stating that cables need to satisfy the requirements of the CPR in respect of their reaction to lire and naktng teftrence to Appendix 2, item 17. ReqLrirements have also been included for cables that are supplying safety ''
i
rclttts.
Chapter 44 Protection against voltage disturbances and electromagnetic disturbances Section -143. u,hich deals rvith protection against overvoltages olatmospheric origin or due to switching, has been redrafted.
The AQ criteria (conditions
of external influence for lightning) for determining if protection against transient
or ert'oltages is needed are no longer included. lnstead, protection against transient oven-oltages has to be provided n'here the consequence caused by overvoltage (see Regulation 443.4):
(i) (ii) (iii) (iv)
t
could result in serious injury to, or loss of, human life, or
i
could result in intenuption of public sericesior damage to and cultural heritage, or
l
could result in interruption of commercial or industrial activity, or could aff-ect a large number of co-located individuals.
For all other cases, a risk assessment has to be perforred in order to determine overvoltage is required.
if protection against transient
There is an exception not to provide protection for single dwelling units in certain situations.
Chapter 46 Isolation and srvitching
A new Chapter 46 has been introduced. Thrs deals with non-automatic local and remote isolation and switching measures for the prevention or removal of dangers associated with electrical installations or electrically powered equipment. Also. switching for the control of circuits or equipment. Where electrically powered equipment is within the scope of BS EN 60204. only the requirements of that standard apply.
Chapter 52 Selection and erection of rviring systems Regulation 521 .10.202, which gives requirements fbr the methods of support of wiring systems, has replaced Regulation 521.11.201. This is a significant change. Regulation 521 .10.202 requires cables to be adequately supported against their premature collapse in the event of a fire and applies throughout the installation, not just in escape routes as previously.
Regniation 521 .1.3 has also been modified, and of the CPR in respect of their reaction to fire.
a
note added stating that cables also need to satisfy the requirements
Chapter 53 Protection, isolation, switching, control and monitoring This chapter has been completely revised and deals with general requirements for protection, isolation, switching. control ar.rd monitoring and with the requirements for selection and erection of the devices provided to fuifil such functions. Section 534 Devices for protection against overvoltage
This section locuses mainly on the requirements for the selection and erection of SPDs for protection against transient overvoltages where required by Section 143,the BS EN 62305 series, or as otherwise stated. Section 534 has been completely revised. The most significant technical change refers to the selection requirements for the voltage protection 1evel. Chapter 54 Earthing arrangements and protective conductors Trvo new regulations (512.2.3 and 542.2.8) have been introduced conceming eafih electrodes.
Chapter 55 Other equipment Regulation 550.1 introduces a new scope.
I
Ne'"v Regulation 559.10 refers to ground-recessed luminaires, the selection and erection of which shall take account of the gr,ridance given in TableA.l of BS EN 60598-2-13.
Part 6 Inspection and testing Part 6 has been completely restructured, including the regulation numbering to align with the CENELEC standard. Chapters 61,62 and 63 have been deleted and their content now forms two new Chapters 64 and 65.
Section 704 Construction and demolition site installations
This section contains a number of small changes, including requirements for external influences (Regulation 104.512.2), and a nTodification to Regulation 704.410.3.6 to include the non-use of the protective measure of electrical separation. Section 708 Electrical installations in caravan/camping parks and similar locations
This section contains a number of changes including requirements fbr socket-outlets, RCD protection, and operational conditions and exterlal influences. Section 710 Medical locations
This section contains a number of sn,all changes including the removal of Table 710. and changes to Regulations 710.415.2.1 to 710.415.2.3 concerning equipotential bonding. ln addition. a new Regulationil0.42l .1.201 states requirements regarding the installation of AFDDs.
Section 715 Extra-low voltage lighting installationS This section contains only minor changes including modifications to Regulation 715.524.201 . Section 721 Electrical installations in caravans and motor caravans This section contains a number of changes to the requirernents concerling electrical separation, RCDs, proximity to non-electrical sen'ices and protective bonding conductors. Section 722 Electric vehicle charging installations
This section contains significant changes to Regulation 722.411.4.1 concen,ing the use of a PME supply. The exception conceming reasonably practicable has been deleted. Changes have also been made to requirements for erternal inflr,rences, RCDs, socket-outlets and connectors. Section 730 Onshore units of electrical shore connections for inland navigation vessels
This is an entirely neu, sectiolr. Section 730 applies to onshore installations dedicated to the supply of inland navigation vessels lbr commercial and administrative purposes, berthed in porls and berths. Most, if not all. of the measures used to reduce the risks in marinas apply equally to electrical shore connections for inland navigation vessels. One of the major differences betu,'een supplies to vessels in a typical marina and electrical shore connections for inland navigation vessels is the size ofthe supply needed. Section 753 Heating cables and embedded heating systems This retitled section has been completely revised. The scope of Section 753 has been extended to apply to embedded electric heating systelns for surlace heating. The requirements aiso apply to electric heating systems for de-icing, frost prevention and similar applications, and cover both indoor and outdoor systems. Heating systems for industrial and comr.nercial applications complying u,'ith BS EN 605 19, BS EN 62395 and BS EN 60079 are not covered. Appendices The follorving main changes have been made u,ithin the appendices:
Appendix
I British
Standards to vn hich reference is made in the Regulations has been updated,
as necessary.
Appendix 3 Time/current characteristics of overcurrent protective devices and RCDs The previous content of Appendix l4 conceming earth fault loop impedance has been moved into Appendix 3.
Appendir 6 Model forms for certiflcation and reporting This appendix includes minor changes to the certificates. changes to the inspections (for new installation work only) for domestic and similar premises with up to 100 A supply, and examples of items requiring inspection lor an electrical installation condition report.
.\ppendix 8 Current-carrving capacity and voltage drop for busbar trunking and powertrack systems
Tni. appendix inciudes -\ppendix
\s
changes regarding rating lactors for curent-carrying capacity.
14 Determination of prospective
fault current
stated earlier, the content of Appendix 14 concerning earth far.rlt loop impedance has been moved into 3. Appendix 1zl now contains infonnation on the determination of prospective fault curent.
.\ppendix
.\ppendix 17 Energy efficiency This is a new appendix that provides recommendations for the design and erection of electrical installations, :rcluding installations having local production and storage of energy, for optimizing the overall efficient use ol .'1
er-tri
c it1z.
The recommendations within the scope of this appendix apply for new electrical installations and modification errsting electrical installations. Much of this appendix will not apply to domestic and similar installations.
It is intended that this appendix will be developed into Parl 8 of BS 1671 in a future amendment.
of
I
Ed The lollou ing editions hai FIRST
EDITiON
e
itions
been published: Errtitled'Rules ancl Regulations for the Prevention ofFire Risks Arising from Electric Lightingl Issued
in
1
SECOND EDITION
Issued
in
1888.
THIRD EDITION
Entitlecl 'General Rules recommended for \Viring for the Supply of Electrical Energyl Issued in 1
882.
897.
in
FOURTH EDITION
Issued
FIFTH EDITION
Entitled'Wirir-rg Rulesl lssued in 1907.
SIXTH EDITION
Issuedin 1911.
in
1903.
SEVENTH EDITION
issued
EIGHTH EDITION
Entitled'Regulations for the Electrical Equipment ofBuildingsl issued in 1924.
NINTH EDITION
Issued
in
1927.
TE,NTH EDITION
Issued
in
1934.
ELEVENTH EDITION
Issued
in
1939.
1916.
Revised, issued in 19,13. Reprinted rr.ith minor Amendments, 1945. Supplement issued, 19.16. Revised Section 8 issued, 1948.
TWELFTH ED]TION
Issued
in
1950.
Supplement issuecl, 1954.
THiRTEENTH EDITION
Issued
in
1955.
Reprinted 1958, 1961, 1962 and 1964.
FOURTEENTH EDITION
Issued
in
1966.
Reprinted rncorporating An-rendrr-rents, 1 968. Reprinted incorporating Amendments, 1969. Supplement on use in metric terms issued, 1969. Amendments issued, I970. Reprinted in metric units incorporating Amendments, 1970. Reprinted i972. Reprinted 1973. Amendments issued, 197.1. Reprinted incorporating Amendments, 197.1. Amendments issuecl, 1976. Reprinted incorporating Amendrr-rents, 1976.
FIFTEENTH EDITiON
Entitled'Regulations for Electrical Installationsl Issued in 1981. (Red Cover) Amendments issued, 1 lanuarv 1983. Reprinted incorporating Amendments, 1983. (Green Cover) Arrendments issued, 1 N'1a1' 1984. Reprinted incorporating Arlendments, 198,1. (Yellow Cover) Amendments issued, 1 .lanuar,v 198-5. Amendments issued, I .fanuary 1986. Reprinted incorporating Amendments, 1986. (B1ue Cover) Amendments issued, 12 lune 1987. Reprinted incorporating Amendrnents, 1987. (Brou,n Cover) Repnnted n,ith minor corrections, 1988. (Brorvn Cover)
SIXTEENTH EDITION
Issued
SEVENTEENTH E,DITION
BS 7671:2008 issued, Januirr,v 2008. (Red Cover)
in 1991. (Red Cover) Reprinted with minor corrections, 1992. (Red Cor.er) Entitled and reprinted as'Requirements tbr Electrical Installations BS 7671:1992'. (Red Cor.er) Amendment No 1 issued, December 1994. Reprinted incorporirting Amendmcnt No 1, 199,1. (Green Cor.er) Amendment No 2 issued, December 1997. Reprinted incorporating Ar-nendment No 2, 1997. (Yellorv Cor.er) Amendment No 3 issued, April 2000. BS 7671:2001 issued, lune 2001. (Blue Cor.er) Amendmer-rt No I issued, Februirry 2002. Arnendment No 2 issued, NIarch 2004. Reprinted incorporating Amendments 1 and 2, 2004. (Brolvn Cover) Reprinted incorporating Anendment No I , 201 1 . (Creen Cover) Amendment 2 issued, Aug 2013. Reprinted incorporating Amendments 2 and 3, 201 5. (Yellorv Cover)
EIGHTEENTH EDITlON
BS 7671:2018 issued, July 2018. (Blue Cover)
Joint IET/BSI Technical Committee JPEL/64 CONSTITUTION as at June 2018 Eur Ing J T Bradley BSc CEng FIET FCIBSE (Chairrnan) P Sayer CEng FIET GCGI (Deputy Chairman)
.for IET Eur Ing G Kenyon BEng(Hons) CEng MIET TechIOSH H R Lovegrove IEng FIET (Chair
-
JPEL/64/A)
D Wigley BEng(Hons) CEng FCIBSE. MIET G G Willard DipEE CEng FIET JP
(Chair
JPEL/64/D)
G Digilio IEng FIEE ACIBSE MSLL and Eur Ing Dr K J Hawken DBA(Hons)CEng FIET FIAgTE MIoD MCGI (Agricultural Engineers Association) S
A MacConnacher B Sc CEng MIEE MlnstR (Association of Manufacturers of Domestic Appliances)
A Greer (Association of Manufacturers of Power Generating Systems) C Marsland (Association of Manufacturers of Porver Generating Systems) S
Mason DipEE CEng MIET (British Approvals Service for Cables)
j
M R Hagger BTech(Hons) AMIMMM (British Cables Association)
Eur Ing J Wright BEng CEng MIET (BEAMA Installation)
PNonjs MIET (BEAMA Ltd) J Parsons MIET
R Hanis
I
P
A
(BEAMA Ltd)
(BEIS
Department for Busiuess, Energy and Industrial Strategy)
Andrcws (BESA)
SanTad
Khan MEng (Hons) CEng MIET MIEEE (BSI liaison GEL 81' PEL 37/1)
G Winter (BT Technology Sen ice
& Operations)
T Benstead MSc BEd MCIBSE MIET (Certsure LLP; Chair
-
JPEL/64/B)
M Darville BA(Hons) MIET (Certsure LLP) Eur Ing J M Maltby-Smith BSc(Hons) PG Dip MBA Cerl Ed CEng MTET (Certsure LLP)
N Bird IEng MIET (Chair
-
JPEL/64/C)
DrA C M Sung BSc(Hons) MSc PhD CEng FIET FCIBSE STMIEEE MEI MHKIE(Ir) (CIBSE and EI) BScEng (Hons), MSc. MBA, CEng. FIET. SMIEEE. MCIGRE (CIGRE-UK)
K
Sir.ir,varclhana
\l
Doughton IEng MIET LCGI (City & Guilds of London Institute)
D hu.ir.r (DC Users Forulr.r)
(EAL)
K
Spanor.v
\l
\\- Coates BEng (E R A Tcchnology Ltd)
R Giddings IEng MIET ACIBSE (ECA) S
\lartin MIET (ECA)
1
C
I
Fi,r'rester IEng
.rirlcy IEng MIET (Elcctrical Contractors'Association of Scotiand
t,/a
SELECT)
MIET MInstLM (Electrical Contractors'Associatiou of Scotland t/a SELECT)
NI Allen BEng(Hons ) CEn-e
\IIET (Electrical
Sat-et-v
First)
D Spillett MIET MIOSH MIIRSM (Energy Networks Association) R Wardak MIET (The GAMBICAAssociation Ltd)
G C T Pritchard BTech(Hons) CEng FILP MIET TechIOSH (HEA & ILP)
K J Morton BSc CEng FIET (Health and Safety Executive) A Wells IEng MIET (Individual capacity Competent Persons Forum) S
Henry MICWCI EngTech TMIET (The Institute of Clerks of Works and Construction Inspectorate of GB)
Eur Ing p Harris BEng(Hons) FIHEEM MIEE MCIBSE (Institute of Healthcare Engineering and Estate Management)
R Jeffens (Intertek Cetification)
A Stone CEng MIET (Liaison
-
M Cotterell (Liaison
-
GEL/82)
M Gilmore (Liaison
-
TCT/7)
FSH/12)
L C BarHng (The Lighting Industry Association) B A1lan BEng(Hons) CEng MIET (NAPIT)
F Berlie MIET (NAPIT)
I Storrar BSc CEng FCIBSE (NHS Scotland) J Eade BEng(Hons) CEng MIET AMIMechE (Professional Lighting and Sound Association)
G Brindle BSc(Hons) CEng MIET CMILT (Railway Industry Association)
I Trueman CEng MSOE MBES MIET (Safety Assessment Federation
-
SAFed)
T Nicklin (Society of Motor Manufactr,rers and Traders Ltd)
C J Tanswell CEng MIEE MCIBSE (Society for Public Architecture, Construction, Engineering and Surveying SPACES) Secretorv
G D Cronshaw CEng FIET
10
Preface 3S -r,-1:l0lg. Requirements tbr Electrical Installations, takes account of the technical substance of
agreements
.:,;ie,l at CENELEC level in Harmonized Documents (HD). Where no CENELEC HD exists. IEC level documents ,:e taken rnto account. In particular, the technicai intent of the following CENELEC HDs and IEC documents is :r;1uded: Year
Document reference
BS 7671
HD 60364-1
2008
Fundamental principles. assessment of ger-reral ..., definitions
Parls
HD 6036,+-4-41
2007 (20t7)
Protcction against electric shock
:lD 60364-4-42
2011 (201s)
Protection against thermal eff-ects
Chapter ,11 Chapterl2
t{D 60364-4-43
2010
Protection against overcurrent
Chapter 43
IEC 6036,1-4-44
2007 (20 1 s)
Introduction to voltage & elcctro disturbanccs
Section
HD 60364-4-442
2012
Protection of lorv voltage installations against temporatl oven'oltages "
Section 442
fD
60364-4-443
2016
Protection against overvoltages
Section
HD 60364-4-444
2012
Measures against elcctromagnetic disturbances
tEC 60364-4-41
2015
Protection against overvoltage
HD 60364-4-46
2016
Isolation and sr.i,itching
HD 60364-5-51
2009 (2013)
Selection and erectiott - Colnmon rules
443 Section 444 Section 445 Chapter 46 Chapter 51
HD 6036/t-5-52
201
Selection and ercction of wiring systems
Chaptel52 Cl.rapter
HD or IEC
1
l.
2,
3
4,10
HD 60364-5-53
2015
Protection. isolation, su'itching, control and monitoring
HD 60364-5-534
201 6
Devices for protectiotl agail-rst overvoltage
53 Section 534
HD 60364-5-54
201 l
Earthing arrangements
Chapter 54
HD 60364-5-551
2010 (2016)
Low voltage gencrating sets
Section 55
HD 60364-5-557
201 3(20 l 6)
Auxiliary circuits
HD 60364-5-559
2012 {2017)
Outdoor li ghting installations
HD 60364-6
20t6
Initial verihcation a bath
or sho"ver
1 Section 557 Section 559 Parl 6
2007 (2011)
Locations containing
HD 60364-7-702
2010
Swimming pools and other basins
Section 702
HD 60364-7-703
2005
Sauna heaters
Section 703
HD 60364-1-704
2007 (2008)
Construction and demolition site installations
Section 704
.rD 60364-7-705
2007
Agricultural and horticultural premises
Section 705
tD
60361-1-706
2007
Locations \\,ith restricted movement
Section 706
FrrHD 60364-7-708
201'7
Caravan parks, camping parks and similar locations
Section 708
.{D 60364-7-709
2010 (2012)
Marinas artd sirrrilal locations
Section 709
-D
2012
Medical locations
Section
7I0 71
jD ':-D
-18,1.7.711 SI
2003
F.rhibitions" shou's and stands
Section
60364-1-'712
200s
Solar photovoltaic (PV) power supply systems
Section
7I2 7I4
:.)
60364-7 -1 14
20t2
Ouldoor liglrting installations
-)
60364-7-715
2012
Extra-lorv voltage lighting installations
Section
715
2010 (2014)
Mobilc or tlatttpot'table units
Section
7 17
2017
Electrical installations in caravans and motor cal'avans
Section 721
60361-7-722
2016
Supply of clectric vehicles
Scction 722
60361-7-129
2009
Operating and maintenance gangways
Section 729
60_164-7-730
2015
Onshore units of electncal shore conncctions for irrland navigatior-r vessels
Section 730
2006
Temporary electrical installations for structures. amusement deviccs and booths at lail'grounds. amllsemcnt parks and circuscs
Section
2014
Heating cables and embedded heating systenls
Section 753
200e (2013)
Extemal influcnces
Appx
5
200
Identification of cot'es, in cables and flexible colds
Appx
7
Energy elficienc1,
Appx
17
'::IEC
..)
.) r) :) l :l :l -
: lr
-
60364-7 -121
^{)361-7-740 o0-164-7-753 "rt,164-5-5 -:uE 52 rtt,16;1-8-1
1
1
2015
I
I
I
I
I
I
I
I
I
I
I
I
I
1
Section
-.D 60364-7-'717
I
Section 701
HD 60364-7-701
60364-7-710
I
7210
r Jittes inbrackets referto the year of issue of amendments to the doculnents'
11
\\.here the aboYe documents contain UK special national conditions. those conditrons har.e been to confim within BS 767 i . If BS 167 I is applied in other countries the above documents should be consulted status of a particular regulation'
incorporated
the
I
of new or al11ended BS 7671 will continue to be amended from time to time to take account of the publication has shown experience that regulations revise to taken has been CENELEC and IEC standards. The opportunity methods' and require clarification or to allow for new technology Institution. both specifications and Reference is made throughout BS 7671 to publications of the British Standards titles whereas throughout BS 7671 they codes of practice. eppendix 1 lists these publications and gives their full are refered to only by their numbers.
ola CENELEC Harmonization Where reference is made in BS 7671 to a British Standard which takes account also relates to any European Document, European Nonn (EN) or IEC standard, it is understood that the reference needs to be taken of any national standard similarly derived from the CENELEC standard, although account national exemPtions.
I
12
tr,
-
,r
f,=_
Note by the Health and Safety Executive 'etv Erecr.rtir.e tHSE lHSE) welcomes the publication of BS 7671:2018, Requiirements for Electrical
Regulations 18th Edition. BS 7671 and the IET/IEE Wiring Regulations have been r: ::\el' rettrred to in HSE guidance over the years. Installations which confotm to the standards iaid down r> -(.-1:101g are regarded by HSE as likely to achieve conformity with the relevant parts of the Eiectricity at .. Regulations 1989. Existing installations may have been designed and installed to conform to the standards .,. -..,11i.. editions of BS 767 I or the IEE wiring Regulations. This does not mean that they will fail to achieve :-.,-,:r.nin n'ith the relevant pans of the Electricity at Work Regulations 1989.
.. ::irrus. tET Wiiing
Notes on the plan of the 18th Edition -
..s
Edition is based on the plan agreed intemationally for the arangement of safety rules for electrical instailations'
-.: r.egr.rlation numbering follows the pattern and corresponding references of IEC 60364. The numbering does hot,
- ...1-*."
necessarily follow sequentially. The numbering system used in Part 7 is explained in Section 700'
digit a Chapter, the third digit a Section and 413 is made up as follows: number .ubsequent digits the Regulation number. For example, Section
:' ,re numbering system used, the first digit signifies
-:
a Par1, the second
PART 4 - PROTECTION FOR SAFETY Chapter 41 (first chapter of Part 4) - PROTECTION AGAINST ELECTRIC SHOCK Section 413 (third section of Chapter4l) - PROTECTIVE MEASURE: ELECTRICAL SEPARATION
Part
1
Part 2 .
sets out the scope, object and fundamental principles. a defines the sense in which celtain terms are used throughout the Regulations, and provides symbols used and a list of abbreviations used in the Standard'
::: subjects of the
subsequent pafis are as indicated below:
Subject
Part Part 3
Part 4
of
Identification of the characteristics of the installation that will need to be taken into account in choosing and applying the requirements of the subsequent Parts. These characteristics may vary from one parl olan installation to another and should be assessed for each location to be served by the installation. Description of the measures that are available for the protection of persons, livestock and property, and against the hazards that may arise from the use of electricity.
Part 5
precautions to be taken in the selection and erection of the equipment of the installation.
Part 6
Inspection and testing.
ParlT
Special installations or locations - particular requirements'
of any particular requirement of the -':re sequence of the plan should be followed in considering the application by subject, but in applying any particular regulations ?:.:sulations. -,r The general index provides a ready reference to are provided, and Cross-references in mind. be bome gulations should s :-.e regulatiion the requirements of related regulations :-.: index is arranged to facilitate this. by a two-part 11any cases! a group of associated regulations is covered by a side heading which is identified --.nrber, e.g. 544.i. Throughout the Regulations where reference is made to such a two-part number, that reference : :o be taken to include uil th. indiuidual regulation numbers which are covered by that side heading and include :r ,l tu'o-par1 number.
-r
and .:.. Regulations use the IEC decimal point numbering system to make it easier to embody future changes and identify to In order CENELEC' and IEC within work standards international ,rl1rlo11s resulting from ongoing represent numbers 100 where number 200 100 or a either carry regulations some :-.rrlnlrrodate future IEC changer Some -:\ELEC Harmonization Document reference numbers and 200 numbers represent UK-only regulations. regulations those when be done only will that 200 numbers; and 100 indicate 'updated'to ::.rlarions have not been .
'- -,-,ire a significant rewrite.
13
PART
1
SCOPE, OBJECT AND FUNDAMENTAL PRINCIPLES CONTENTS CHAPTER I1
SCOPE
110.1
GENERAL
110.2
EXCLUSIONS FROM SCOPE
113
EQUIPMENT
't'14
RELATIONSHIP WITH STATUTORY REGULATIONS
115
INSTALLATIONS IN PREMISES SUBJECT TO LICENSING
CHAPTER 12
OBJECT AND EFFECTS
120
GENERAL
CHAPTER 13
FUNDAMENTAL PRINCIPLES
13'l
PROTECTION FOR SAFEW
131 .1
General
131.2
Protection against electric shock
131 .3
Protection against thermal effects
131.4
Protection against overcurrent
13't.5
Protection against fault current
131 .6 131 .7
Protection against voltage disturbances and measures against electromagnetic disturbances Protection against power supply interruption
132
DESIGN
132.1
General
132.2
Characteristics of available supply or supplies
I
JZ,5
Nature of demand
132.4
Electrical supply syslems for safety services or standby electrical supply systems
132.5
Environmental conditions
I
JZ.O
132.7
Cross-sectional area of conductors Type of wiring and method of installation Protective equipment
132.9
Emergency control
132.10
Disconnecting devices
132.11
Prevention of mutual detrimental influence
132.12
Accessibility of electrical equipment
132.13
Documentation for the electrical installation
132.14
Protective devices and switches
132.15
lsolation and switching
132.16
Additions and alterations to an installation
'133
SELECTION OF ELECTRICAL EQUIPMENT
133.1
General
133.2
Characteristics
IJJ.J
Conditions of installation Prevention of harmful effects
133.5
New materials and inventions
134
ERECTION AND INITIAL VERIFICATION OF ELECTRICAL INSTALLATIONS Erection
134.1
lnitial verification PERIODIC INSPECTION AND TESTING
14
PART
1
SCOPE, OBJECT AND FUNDAMENTAL PRINCIPLES
CHAPTER
11
SCOPE 110.1
110.1.1 (D
(ii) (iii) (iv) (") (vi) (vii) (viii) (ix)
GENERAL The Regulations apply to the design, erection and verification ofelectrical installations such as those of:
residential premises commercial premises public premises industrial premises prefabricated buildings
low voltage generating
sets
highway equipr.nent and street fumiture locations containirg a bath or shower swimming pools and other basins
(x) rooms and cabins containing sauna heaters (xi) construction and demolition sites
(xii) aglicultural and horticultural premises (xiii)
corducting locations with restricted movement
(xiv)
caravan / camping parks and similar locatious
(*.r) malinas and similar locations (xvi)
medical locations
(xvii) exhibitions. shows and stands (xviii) solar photovoltaic (PV) power supply systems (xix) outdoor lighting (xx)
extra-low voltage lighting
(xxi) mobile or transpoftable units
(rxii)
caravans and motor caravans
(xxiii) electric vehicle charging (xxiv) operating and maintenance gangways
irixv) tempomry installations for stmctures, amusement devices and booths at fairgrounds,
a[.rusement parks and
circuses including professional stage and broadcast applications
(rxvi) floor and ceiling heating systems (xxvii) onshore units of electrical shore connections for inland navigation NOTE:
vessels.
"Premises" covers the land and all facilities including buildings belongirlg to it.
'l'10,1.2 The Regulations include requirements for: (i) circuits supplied at nominal voltages up to and including 1000 V AC or 1500 V DC. For AC, the preferred frequencies which are taken into account in this Standard are 50 Hz, 60 Hz and 400 Hz. The use of other frequencies for special purposes is not excluded
(ii)
circuits, other than the intemal wiring ofequipment, operating at voltages exceeding 1000 V and derived from an installation having a voltage not exceeding 1000 V AC, e.g. discharge lighting, electrostatic precipitators
tiii) (i\,) (\)
wiring systems and cables not speciflcally covered by the standards for appliances
tr
i)
all consumer installations extemal to buildings
fixed wiring for information and communication technology, signalling, control and the like (excluding internal wiring of equipment) additions and alterations to installations and also parts ofthe existing installation affected by an addition or
alteration.
-.l
15
'110.1.3 The Regulations are intended to be applied to electrical installations generally but, in certain cases. they may need to be supplemented by the requirements or recommendations of other Bdtish or Harmonized Standards or by the requirements ofthe person ordering the work. Such cases include the following:
(i) Electric signs and high voltage luminous discharge tube installations - BS 559 and BS EN 50107 (ii) Emergency lighting - BS 5266 and BS EN 1838 (iii) Explosive atmospheres - BS EN 60079 (iv) Electrical apparatus for use in the presence of combustible dust - BS EN 50281 and BS EN 60079 (v) Fire detection and fire alarm systems for buildings - BS 5839 (vi) TeJecommunications systems - BS 6701 (vii) Electric suface heating systems - BS EN 60335-2-96 (viii) Electrical installations for open-cast mines and quarries - BS 6907 (ix) Temporary electrical systems for events, entertainment and related purposes - BS 7909 (x) Life safety and firefighting applications - BS 8519 and BS 9999.
110,2
EXCLUSIONS FROM SCOPE
The Regulations do not apply to the following installations:
(i) (ii) (iii)
Systems for the distribution of electriciq, to the public
Railway traction equipment, rolling stock and signalling equipment Equipment ofmotor vehicles, except those to which the requirements ofthe Regulations conceming caravans or mobile units are applicable
(iv) Equipment on board ships covered by BS 8450, BS EN 60092-507, BS EN ISO 13297 or BS EN ISO 10133 (v) Equipment ofmobile and fixed offshore installations (vi) Equipmentofaircraft (vii) Those aspects ofmines specifically covered by Statutory Regulations (viii) Radio iuterlerence suppression equipment, except so far as it affects safety ofthe elecfiical installation (ix) Lightning protection systems for buildings and structures covered by BS EN 62305 (x) Those aspects of lift installations covered by relevant parls of BS 5655 and BS EN 81 and those aspects ol escalator or moving walk installations covered by relevant parts of BS 5656 and BS EN I 15
(xi) (xii) (xiii)
Electrical equipment of machines covered by BS EN 60204 Electric fences covered by BS EN 60335-2-76
The DC side of cathodic protection systems complying with the relevant part(s) of BS EN ISO 12696, BS EN 12954, BS EN ISO 13174, BS EN 13636 and BS EN 14505.
111
/Vot used
112
Nof used
't't3
EQUIPMENT
The Regulations apply to items ofelectrical equipment only so far as selection and application ofthe equipment in the installation are concemed. The Regulations do not deal with requirements for the constuction ol assemblies ofelectrical equipment, which are required to comply with appropriate standards. '113.1
114
RELATIONSHIP WITH STATUTORY REGULATIONS
114.1 The Regulations are non-statutory They may, however, be used in a court oflaw in evidence to claim compliance with a statutory requirement. The relevant statutory provisions are listed in Appendix 2 and include Acts ofParliament and Regulations made thereunder. In some cases statutory Regulations may be accompanied by Codes of Practice approved under Section l6 of the Health and Safety at Work etc. Act 1974. The legal status of these Codes is explained in Section 17 ofthe 1974 Act. For a supply given in accordance with the Electricity Safety, Quality and Continuity Regulations, it shall be deemed that the connection with Ealth of the neutral of the supply is permanent. Outside England, Scotland, Wales and Northem Ireland, confimatiol shall be sought from the distributor that the supply conforms to requirements
conesponding to those of the Electdcity Safety, Quality and Continuity Regulations (ESQCR), in this respect. Where the ESQCR does not apply, equipment for isolation and switching shall be selected accordingly as specified in Chapte$ 46 and 53.
16
I I
I
I
INSTALLATIONS IN PREMISES SUBJECT TO LICENSING
115
115.1 For installations in premises overwhich a licensing or other authority exercises a statutory control, the requirements ofthat authority shall be ascertaired and complied with in the design and execution ofthe installation.
CHAPTER 12 OBJECT AND EFFECTS
120
GENERAL
This Standard contains the rules for the design, erection and verification ofelectrical installations so provide for safety and proper functioning for the intended use.
120.1 es to
120.2 Chapter 13 states the fundamental principles. It does not include detailed technical requirements. shich may be subject to modification because oftechnical developments.
120.3 This Standard sets out technical requirements to enable electrical installations to conform with the i'undamental principles ofChapter 13, as follows: Part 3
Assessment of geneml characteristics
Part 4
Protectiol for safety
Part 5
Selectio1,I and
Part 6
Inspection and testing
Part 7
Special installations or locations.
erectiol] ol equipmelt
:-::i inte[ded deparlure from
these Parls requires special consideration by the designel olthe installation and shall recordcd on thc appropriatc clcehical cefiification specified in PaIt 6. The resulting degree of safety ofthe :.:.illation shall be not less than that obtained by compliance with the Regulations.
-.
I I
CHAPTER 13 FU N DAMENTAL
.31 '31,1
PRINCIPLES
PROTECTION FOR SAFETY
General
-- : ri.rlrirernents ol this chapter are intended to provide for the safety of penons, livestock and propefty against . and damage which lray arise in the reasonable use of electrical installations. The requirements to provide --:. ' : -: !31'etv of livestock are applicable in locations intended for them. -.
. -::: cal
irstallatiol1s, risk of injury may result from:
::lLjCk CUlTentS
:ri.essi\ e temperatures likely to cause bums, fires and other injurious effects r:r jtion ol a potentially explosive atmosphere ---.ccn oltages. overvoltages and electromagnetic disturbances likely to cause or result in injury or damage :;hanical movement ofelect cally actuated equipment, in so far as such injury is intended to be prevented :. ;l;ctrical emelgency switching or by electrical switching for mechanical maintenance of non-electrical : r: : rri such equipment
tto
t)
.
rr suppl) interruptions and/or interruption of safety services
:--..-.: or bun'ril1g. Iikely to cause blinding effects, excessive pressure and/or toxic
gases.
17
131.2
Protection against electric shock Basicprotection
131.2.1 NOTE:
For low voltage installations, systems and equipment, 'basic protection' generally corresponds to protection agaiosr 'direct contact'.
Persons and livestock shall be protected against dangers that may arise from contact with live parts ofthe installation.
This protection can be achieved by one ofthe lollowing methods:
(i) (ii)
Preventing a curent from passing through the body of any person or any livestock
Limiting the curent which can pass through
131.2.2 NOTE:
a
body to a non-hazardous value.
Faultprotection
For low voltage installations, systems and equipment, 'fault protectiofl' genemlly corresponds to protection agaiDst 'indirect contact', mainly with regard to failure ofbasic insulation.
Persons and livestock shall be protected against dangers that may arise ftom contact with exposed-conductive-parts
during a fault. This protection can be achieved by one ofthe following methods:
(i) (ii)
Preventing a curent resulting from a fault from passing tkough the body ofany person or any livestock
Limiting the rnagnitude ofa curent resulting from a fault, which
can pass through a body, to a non-hazardous
value
(iii)
Limiting the dumtion of
a
curent resulting from
a
fault, which car pass through
a
body, to a non-hazardous
time period. In connection with fault protection, the application ofthe method ofprotective equipotential bonding is one ofthe impodant principles for safety.
Protection against thermal effects
131.3
1 31 .3.1 The electrical installation shall be so ananged that the dsk of ignition of flammable materials due to high temperature or electric arc is minimized. In addition, during nomal operation ofthe electrical equipment, there shall be minimal lisk ofbums to persons or livestock.
'13'|.3'2 Persons, livestock, fixed equipmeut and fixed materials adjacent to electrical equipment shall be protected against hannful effects ofheat or thermal radiation emitted by electrical equipment, and in pafiicular the following:
(i) (ii) (iii)
Combustion, ignition, or degradation ofmatedals Risk olbums
Impaiment of the safe function of installed equipment.
Electrical equipment shall not present a fire hazard to adjacent materials. 131.4
Protection against overcurrent
Persons and livestock shall be protected against injury, and property shall be protected against damage, due to excessive temperatures or electromechanical stresses caused by any overcurrents likely to arise in live conductor-s.
NOTE: 131.5
Protection can be achieved by limitiDg the overcurrent to a sale value and/ol duration.
Protection against fault current
Conductors other than live conductors, and any other parls intended to carry a fault current, shall be capable of carrying that current without attaining an excessive temperature. Electrical equipment, including conductors, shall be provided with mechanical protection against electromechanical stresses of fault curents as necessary to prevent injury or damage to persons, livestock or property.
131.6
Protection against voltage disturbances and measures against electromagnetic disturbances
131.6.1 Persons and livestock shall be protected against injury and property shall be protected against any harmful effects, as a consequence ofa lault between live parts ofcircuits supplied at different voltages, in accordance
with Section 442.
1B
131.6.2 _: :--::a.
.
,..s
:.:':::;1 :itill
P.:..:.::l i] aot]si,i..t.-ua
be prOrected .rgain.l rnjury. and propetn shal1 be protected ayain'r
i i i Ll\ 3n rrliages such as those or iginatiDg
t'l
om atmospl'lelic e\ enls or 1}om s$ itchiLlu. in
-:-..nce \\ irh Section -l-+].
\OTE:
tor protectio[ against ]ightning strikes' refer to the BS EN 62305 series'
protected agajnst Persol1s and ]ivestock shall be protected against iniury. and property shall be with Scction'145in accordancc lecovery, voltage -:gi. as a consequence ofunden'oltage and any subsequent
131,6.3 -:::
so The installation shall have an adequate level of irlmunity agairst electlornagrletic dLsturbances shall design The installation 444. Section with in accordance iilnclion correctly in the specified environment, the installed ilrto consideration the anticipated electromagnetic emissions, generated by the installation o[ irstallation' the to' or conlected with, used equipment currenlusing which shall be suitable lor the
31.6.4
.i
.
:
',,:
I
-,-i:ment.
-
Protection against power supply interruption
131.7 ,.
:
ploYisions shall be nrade in rere danger or danrage is expected to arise due to an intenuption of supply, suitable : il'rstallation or installed equipment.
132
DESIGN
132.1
General
provide for: The electrical installation shall be designed by one or more skilled persons to (i) the protection ofpersons, livestock and property in accordance with Section l3 [
tii)
I
the proper functioning ofthe electrical installation for the intended use'
lequilements with which the The information required as a basis for design is stated in Regulations 132.2 to 5. The cesign shall comply are stated in Regulations 132.6 to 16
Characteristics of available supply or supplies
132.2
i.tbnnation onthe characteristics ofthe available supply or supplies shall :nquiry ot inspection.
be determined by calculation, tlreasurement'
132 13 to show ilre following characteristics shatl be included in the documentation referred to iI] Regulation
:ontbrmity with the Regulations: (i) Nature of curent; AC and/orDC
(ii)
Purpose and number ofconductors: for
AC line conductor(s) neutml conductor Protective conductor PEN conductor
,
for DC conductors equivalent to those listed above (outer/uricldlc/earthcd livc coilduetds. l)rolcttr\e colductor, PEN conductor)
(iii)
Values and tolerunces:
norninal r oltage and voltage tolerances nominal frequency and frequency tolerances maximum curent allowable prospective fault current
(iv)
extemal earth fault loop impedance Protective measures inherent in the supply, e.g. earthed neutral or mid-wire
(v) Particular requirements of the distributor HOTE:
lfthe dist butor
changes the characteristics ofthe power supply this may affect the safety
ofthe irstallation
19
Nature of demand
132.3
Thenumberandtypeolcircuitsrequiredforlightirg,heating,power'control'signalling'communicationand information technology" etc. shall be determined ftom knowledge of:
(i) location ofpoints ofpowet demand (ii) loads to be expected on the va ous circuits (iii) daily and yearly variation ofdemand (iv) any special conditions, such as hannonics (v) requiremetts ior control, signalling, communication (vi) anticipated futurc demand, ifspecified'
and infotmation technology' etc'
supply systems Electrical supply systems for safety services or standby electrical
132.4
is specifiedthe following shall be detemined: Where a supply for safety services or standby electdcal supply systems
(i) (ii)
Characteristics ofthe suPPlY
Circuits to be supplied by the safety source'
Environmental conditions
132.5
envilonmental conditions to which The dcsign ofthe electlical installation Shall take into account the be subjected.
132.5,,| it will
132.5.?Equipmentlnsuffotlndingssusceptibletoriskoffireorexplosionslrallbesoconstructedorplotected.
and such other spicial precautions shall be taken, as to prevent danger'
132.6
Cross-sectional area of conductors
operating conditions and' r"here The cross-sectional atea of conductors shall be determined for both normal appropriate, fot fault conditions according to:
(i) the adl.rissibJe r]laxinluln tcmperature (ii) the adnrissible voltage drop (iii) the clectromechalical strcsses likely to occur clue to short-circuit and eafth fault cun'ents (iv) other n.rcchanical sttesses to rvhich the conductors are likely to be exposcd (v) thc naximurl in.rpedarcc lor correct operation o f shotl-cit'cuit and carth fault protectior (vi) the [rethod of installatiorl \,ij) harmonics (viii) therualinsulation (
132.7
Type of wiring and method of installation
shall include consideration ofthe following: The choice olthe type of wiring system and the firethod of installation
(i) The rature ofthe location (ii) The uature ofthe stmcture supporting the wi ng (iii) Accessibility of wiring to persons and livestock (iv) Voltage (v) The electromechanical stresses likely to occur due to shoft-circuit (vi) Electromagneticinteference
and earth fault culTents
(vii)otherexternalinfluences(e.g'nreclranical.thermaland'thoseassociatedwithfirc)towhichthewiringis Iikely to be exposed during the erection ofthe electrical installation or in service' 132-8
Protective equiPment
with respect to theil function, including plotection The charactedstics ofprotective equipment shall be detennined against the effects of:
(i) (ii) (iii) 1ir ;
overload
lault curent over.roltage
underroltage attd no-roltage.
and time which are suitably related to the The protective devices shall opemte at values of current, voltage characteristics oftbe circuits and to the possibilities ofdanger' 2A
EmergencY control
132.9
rapidly it can be easily recogrrize<1 and eflectively and device shall be installed in Such a way that supply intenuption ofthe of aungt',if'"t"it *"tt'ity for immediate operated where, in tf.r" "
An
intelpting
132.10
"u,t Disconnectingdevices
DisconnectilgdevicesshallbeprovidedSoaStopermitSwitchingand/orisolationoftheelectricalinstallatiotl, inspection. testing, fault detectjon' tlaintenalce circuits or individuat iterrs orequipmJiiu,
,.qrrir"i rol op.ration,
ald tepait.
132.11
Prevention of mutual detrimental influence
i, such a way that no mutual detrimental influence The electrical i,stallation shall be ananged .i".t.i.ul lt',rtuttutions and non-electrical installations'
will occur between
into account Electromagnetic interference shall be taken
132.12
Accessibility of electrical equipment
provide: Electdcal equipment shall be ara11ged to
(i)sufficientspacefortheinitialinstallationandlatelreplacementofindividualitemsofelectricalequipnrent
(ii)
fault detection' lnaintenance and repair accessibility for operatlon, inspection' testing'
132.13
Documentation for the electrical installation
Frervelectricalinstallationshallbeprovidedwithappropriatedocumentation.includilgthatrequiredbyRegulations :rj.i. sr+.s, 536.5, Part 6 and, where applicable' Parl 7'
132.14 132.14.1
Protective devices and switches be inserled in the line conductor only' A single-pole fuse, switch or circuit-breaker shall
132.14.2Noswitchorcircuit-breaker'exceptwherelinked'orfuse'shallbeinsertedinanearthedneutral shall b(r arrallged -ur.ur.", i,rr"rted in an eafihed neutral corlductor ;onductor. Any linkeo s*ltct, n, tirLlo-"ir"ui rreak all the related line conductors'
132.15
to
lsolation and switching
lg2.l5,2olEffectlvemeans,Suitablyplacedforreadyop^eration.shallbeprovicledsothatallvoltagemaybecut p'event or equipment, as may be necessary to
:l
r-lom every installation, :::love danger.
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all
132.15.?OZEveryfixedelectricmotorshallbeprovidedwithanemcientmeansofswitchirlgoff'readily
:';t,b;, easily operated and so placed as to prevent danger 132.16 Additions and alterations to an installation
\:
shall.be made adrlition or alteration, temporary or pernarent' !^rouu6 -"*''"--ur 4.] ano [ne conurlrur if necessary for the -ceriained that the mtlng the eafthing andtr Lndrrg arlngements, Furthemorc' l:Juate for the altered circumstances hF adequate' ^-. ^r+^-^I;,\6 shall be ^rlenrrrfe for the safety of the addition or altemtion "L.ll '- ,.:;it. ;;;t; "pplied SELECTION OF ELECTRICAL EQUIPMENT
l:-1',:if:ll"*-'lT:?'51*;ln',[l1titl: ::.fi[T#,"Ji:'iJl[."ls',i'J'J#,l]il';i;;.-i'i,"g.q"tp-.i'rtrl1'::":Y:"11",1*:l::i:I]il,i:
133 133.1
General
Standard llthe the appropriate Bdtish or Hannonized Every item of equipment shall cornply \\' ith intt'nutio'at (IEC) standard or the approp ate Ji*ff l" t"O"io tttt .--.ince ofsuch a stunAu,O, "pp'op'iute '"f""'"t i--rJard of another country'
133.1.1
be selected by special the item of equipment concerned shall Where there are no applicable standards' rhe installation and the ln5taller' -=-,..n..tbetueen the person specilying
133.1
.2
':3
where equipment to be used is not in accordanc' or otI'-r PeLSwr r!rPv! J -'- -.- : i1s stal1dard, the desrgner
1.3
-. -l deg'* .**i,r.t,,-pr"t:ia.t sju1P.rc,t PrurrulJat least the same
'it']"11*1111::.)],i;l,l"T.ii,1#X]',',1; ll]: -r Such use co,Iilia,rce
'{:. l:T::::",:5,:tr^* .
",f specified in Parl 6' *rr1l be recorded on the approprlate 'eleitrical certidcation
.-
nuith the
Regulatiors.
I I
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21
I
133.2
Characteristics
suitabie characteristics applopriate to the values and is based and shal1. in palticular'' fllfi1 conditions on $tich the desigrl ol the electrical installation (see section 132)
Eren iren ol elecrrical equip[reni selected shall hale the requirenterts ofRegulations 133.2.1 to 4.
'.|33.2.1
Voltage
voltage (ms value for AC) Electrical equipr-nent shatl be suitable with respect to the maximum steady-state to be app)ied, as well as ovenoltages likely to occur'
NOTE:
likely
I
voltage likely to occur' For cer-tairl equipment, it may also be necessary to take account ofthe lowest
133.2,2
Current
current (nns value-fol AC) which it has Electrical equip[rent shall be selected with lespect to the maximun'I steady in abnormal conditions and the period car-rietl to carry i[ normal ser-vice and with respect to the curlelt likely to be to flow' (e.g. operating time olprotective devices, if any) during which it may be expected
133.2.3
I
FrequencY
Equipment shall be suitable for the frequencies likely to occur in the circuit
133.2.4
Power
Elect cal equipment which is selected on the basis ofits powel characteristics shall be suitable ofthe equipmcnt, taking into account the load factor and the normal sewice conditions'
133,3
for the duty demanded
Conditions of installation
the environmental conditions Electlical equipment shall be selected so as ro withstand safely the stresses' does not by design have (see Regulatior 132.5) and the characteristics of its location. An item of equipment which
tl].p,op-"ni.."or,.Spondingtoitslocationmaybeusedwhereadequatefufiherplotectionispl.ovidedaspartofthe conrpleted electrical installation.
Prevention of harmful effects
133.4
equipment or impail the electrical equipment shall be selected so that it will not cause harmful effects on othel supply during nonnal service, including switching operations
A11
NOTE:
Examples of characteristics which are likely to have hannful effects ale given
133.5
h
Chapter 33
New materials and inventions
the resulting degree ofsalety Where the use ofa new matedal or invention leads to depaftures from the Regulations, Suchuse sl.tall ber"co|ded the Regulations with complianae by obtained olthe installation shallbenot less than that Par16 in specifled on the appropriate electrical certilication
ERECTION AND INITIAL VERIFICATION OF ELECTRICAL
134
'134.1
instructions. The characteristics ofthe electrical equipment, as determined in accoldance not be impaired by the process of erectiott.
134.'1.2
$ith Section tSl shall
oftenrlnals is Conductors shall be identified in accordance witl, Section 514. \\:here id.-ntification recessary, tlley shalt be identified in accordance with Section 514'
114,1.3
Evely electdcal joint and connection shall be of proper construclirrn as regards conductance'
insulation. mcchanir4l strength and protection.
l34,l,5ElectricalequlpmentshallbeinstalledinSuchamannelthatthedesigntempemtuesar.]0iexceeded. place; Electrical equipment likely to cause high temperatures or elecinc ercs shall be materials as to minimize the risk of ignition of flammable
134,1.6
22
I
Erection
,1
134-1.4
I
INSTALLATIONS
proper mater ials shall be used i[ Good workmanship by one or more skilled or instructed persons and shall take account ofmanufacturers' the erection ofthe electrical instaliatiln. The installation ofelectdcal equipment
j34.1
I
::
guarded so
I
Where the temparaturc of an cxposcd part of cicctrical cquipmcnt is likcly kr causc injury to persons or liveslock that part shall be so located or guarded as to prevent accidertal contact therewith.
134.1.7 134.2 134.2.1
Where necessary for safety purposes, suitable waming signs and/or notices shall be provided.
lnitial verification Dudng erection and on completion of an installation or an addition or alteration to an installation,
and before it is put into seryice, appropriate inspection and testing shall be carried out by skilled pesons competent to verify that the requirements ofthis Standard have been met.
Appropriate certiflcation shall be issued in accordance with Chapter 64.
I
134.2.2 The designer of the installatior.r shall make a recommendation for the interval to the fir.st periodic inspection and test as detailed in Chapter 64.
I
NOTE: 13s
The requirements ofChapter 34 (maintainabilily) should be taken into consideration.
PERIODIC INSPECTION AND TESTING
It is recommended that every electrical installation is subjected to periodic inspection and testing, in accordance with Chapter 65. 135.1
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PART 2 DEFINITIONS For the puposes of the Regulations, the following definitions shall apply. As far as practicable the definitions align with the Intemational Electrotechnical Vocabulary and BS 4727 - 'Glossary of electrotechnical, power, telecommunicatiol, electronics, lighting and colour terms'.
NOTE:
Whcre a section nunber is listed, e.g. {444}, the deflnition only applies within that section.
8/20 Current impulse, {534}. A curent impulse with a virtual fi-ont time of 8 [s and a time to half-value of20 ps where:
(i)
the
ftort timc is delined as
1.25(teo - tro), where teg and tro are the
90% and 10% points o1 the leading edge
ofthe wavefom
(ii)
the time to half-value is defined as the time between the virtual origin and the 50% point on the tail. The vitual origin is the point where a straight line drawn through the 90% and 10% points on the leading edge ofthe wavefor-m intersects the I : 0 line.
Accessory. A device, other than curent-using equipment, associated with such equipment or with the wiring
olan
installation.
Agricultural and horticultural premises. Rooms, locations or
areas where:
livestock are kept, or feed, 1'eltilizers, vegetable and animal products are produced, stored, prepared or processed, or plants are glown, such as greenhouses.
Ambient temperature. The temperature ofthe air or other medium where the equipment is to be used. Amusement device. Ride, stand, textile or membrane building, side statl, side show, tent, booth or gmndstand intended for the entefiaiflrent ofthe public. Appliance. An item ofcurent-using equipment other than
a
luminaire or an independent motor.
Arm's reach. A zone ofaccessibility to touch, extending from any point on a surface where move about to the limits which
a
persons usually stand or
person can reach with a hand in any direction without assistance. (See Figure 417.)
Arrangements for livestock keeping. Buildings and rooms (housing for animals), cages, runs or other containers used for continuous accommodation of livestock.
Auxiliary circuit. CircrLit for transmission ofsignals intended for control, detection, supervision or measulement of the frLnctrunrlstatus
ofa llrain circuit.
Back-up protection, Protection of a device by overcurent co-ordination between that device and an overcurent protective device (OCPD) in series with it, generally but not necessarily on the supply side. This prevents ary ercessir e slress on the electrical devicc.
NOTE:
In this standard. back-up protection is not ihe same as combined shoft-circuit protectiorl.
Barrier. A pat providing
a
dcfined degree ofprotection against contact with live parts from any usual direction
of
Basic insulation. Insulation applied to live parls to provide basic protection and which does not necessarily include insulation used exclusively for functional purposes. Basic protection. Protection against electric shock under fault-free conditions. For low voltage installations. systerns and equipnlent. basic protection generally conesponds to protection against dircct contact. that is "contact ofpersons or livestock with livc pafts".
Basin of fountain. A basin not intended to be occupied by persons and which cannot be accessed (reached by persons) without the use ofladders or similar means. For basins offountains which may be occupied by persolls, the requirements for swimrring pools apply. Bonding conductor. A protective conductor providing equipotential bonding.
Bonding network (BN), {444}. A set of interconnected conductive parts that provide a path for currents
at
frequencies from direct cunent (DC) to radio frequency (RF) intended to divert. block or impede the passage
of
electronagnetic energy.
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access.
NOTE:
I
Bonding ring conductor (BRC)! {444}. Abus eathing conductor in the form ofa closed ring. NOTE: Normaily the bonding dng conductor, as paft of the bonding network, has multiple con[ections to the common bonding network (CBN) that improves its performance.
Booth. Non-stationary unit, intended to accommodate equipment generally for pleasure or demonstration purposes. space within the structure or the components of a building accessible only at certain points. Such voids include the space within partitions, suspended floors, ceilings and cefiain types ofwindow frame,
Building void, accessible, A door frame and architrave.
Building void, non-accessible. A
space within the structure or the components
of
a
building which has no ready
rleans of access. Bunched. Cables are said to be bunched when two or more are contained within a single conduit, duct, ducting. or trunking o1 ifnot enclosed, are not sepamted from each other by a specified distance.
Busbar trunking system. A type-tested assembly, in the form of an enclosed conductor system comprising solid conductors separated by insulating material. The assembly may consist ofunits such as:
-
busbar trunking units, with or without tap-off facilities
tap-off units where applicable phase-tmnsposition, expansion, building-movement, flexible, end-feedir anrl adaptor units
NOTE:
Othcr systern components may include tap-offunits.
Bypass bonding conductor, {444}. Bonding conductor connected in parallel with the screens ofcables. Cable channel. An enclosure situated above or in the ground, ventilated or closed, and having dimensions which do not pemit the access of pemons but allow access to the conduits and/or cables throughout their length during and after installation. A cable channel may or may not form part ofthe building construction'
Cable cleat. A component of a support system, which consists of elements spaced at intervals along
tl.re
length
of
the cable or conduit and which mechanically retains the cable or conduit.
Cabte coupler. A means of enabling the comection or disconnection, at will, of two flexible cables. lt consists of
a
connector and a plug.
Cable ducting. An enclosure of metal or insulating material, other than conduit or cable trurking, intended for the protection of cables which are drawn in after ercction ofthe ducting,
Cable ladder. A cable support consisting of a series of transverse supporting elements rigidly fixed to main longitudinal supporting membels. Cable tray. A cable support consisting ofa continuous base with raised edges and no covering. A cable tray may or may not be perforated.
Cable trunking. A closed enclosure normally of rectangular cross-section, of which one side is removable or hilged, used for the protection ofcables and for the accommodation ofother electlical equipment. Cable tunnel. A coridor aontaining supporting structures for cables and joints and/or other elements of wiring systems and whose dimensions allow pe$ons to pass freely throughout the entire lergth' Caravan. A trailer leisure accornmodation vehicle, used for touring, designed to meet the requirements for the colstruction and use ofroad vehicles (see also definitjons of Motor caravan and Leisure accot.ulodation vehicle). Caravan park / camping park. Area ofland that contains two oI mole calavan pitchcs and/ol tents. Caravan pitch. Plot of ground intended to be occupied by a leisure accommodation vehicle' Caravan pitch electrical supply equipment. Equipment that provides means of connecting and disconnectilg supply cables from leisure accommodation vehicles or tents with a mains electrical supply
Cartridge fuse link. A device comprising a fuse elernent or two oI more fuse elements connected in parallel (see fuse link). encloseJin a cartridge usually filled with arc-extinguishing medium and connected to temrinations
central power supply system. A system supplying
the required emergency powel to essertial safety equipmert.
Central power supply system (low power output). Central power supply system with a liriritation of the power output ofthe system at 500 W for 3 h or I 500 W for t h
NOTE:
A low power suppiy system nonnaily cornprises a mailtenancc-frec battety and
a
chal€ing and tcsting Lrnit.
Circuit, An assembl), of electrical equipment supplied from the same origin and protected agatnsi or ercurrenr b! the same plotective device(s). Circuit-breaker. A device capable of n.raking, carrying and breaking notmal load currents and also making and automatically breaking, under predetermined conditions. abnomal curents such as short-circuit currents. It is usually required to operate inftequently although some tlpes are suitable for frequent operation'
Circuit-breaker, Instantaneous
trip (ICB).
Circuit-breaker which only fulfils the short-circuit pofiion of
overcurrent protection.
Circuit-breaker, linked. A circuit-breaker the contacts of which are so aranged as to make or break all poles simultaneously or in a definite sequence.
Circuit protective conductor (cpc). A protective conductor connecting exposed-conductive-parts of equipment to the main eathing termilal. Class
I equipment. Equipment in which protection
which
includes ryreans
ofthe installation
against electdc shock does not rely on basic insulation on1y, but a protective conductor in the fixed wiring
for the connection ol exposed-conductive-parts to
(see BS EN 61140).
against electdc shock does not rely on basic insulation only, but in which additional safity precautions such as supplementary insulation are provided, there being no provision for the connection ofexposed metalwork ofthe equipment to a plotective conductor, and no reliance upon plecautions to be taken ir the fixed wiring ofthe installation (see BS EN 61140). Class
II equipment. Equipment in which protection
Ctass III equipment. Equipment in which protection against electric shock relies on supply at SELV and in which voltages higher than those of SELV are not genemted (see BS EN 61 140).
Cold tail. The interface between the fixed installation and a heating unit Combined short-circuit current capability. Maximum shofi-circuit cu-rent which can be handled by two shotcircuit protective devices in series.
Combined short-circuit protection. Overcufient co-ordination, in short-circuit conditions, of two OCPDS in series, resulting in a combined shoft-circuit curent capability higher than one OCPD alone'
common equipotential bonding system, common bonding netrvork (CBN), {444}. Equipotential bonding system providing both protective equipotential bonding and functional equipotential bonding'
Complementary floor heating, Direct heating system integrated into the ffoor constructiol, for example, in the border zones close 1o outer walls, which complements the heat dissipation ofa thermal storage floor heating system. Conditional short-circuit current, Prospective current that
a
circuit or a switching device, protected by a specified
short-circuit protective device, can satisfactodly withstand for the total operating time ofthat device under specified conditions ofuse and behaviour,
Conducting location with restricted movement.Alocation comprisedmainly ofmetallic or conductive surrounding par.ts, within which it is likely that a person will come into contact through a substantial portion of their body with ihe conductive surounding parts and where the possibility ofpreventing this contact is limited. Conduit. A pafi of a closed wiring system for cables in electrical installations, allowing them to be drawn in and/ or replaced, but not inserted laterally.
Connector. The part of a cable coupler or of an appliance coupler which is provided with female contacts and is intended to be attached to the end ofthe flexible cable remote frorn the supply.
Consumer unit (may also be known as a consumer control unit or electricity control unit). A parlicular type of distribution board comprising a type-tested co-ordinated assembly for the control and distdbution of electrical energy, principally in domestic premises, incorporating manual means of double-pole isolation on the incoming .ircrr-it1rl unO an usembly ofone or more fuses, circuit-breakers, residual current operated devices or signalling and other devices proven dudng the type{est ofthe assembly as suitable for such use
Continuity of service. The extent to which the operation of an electrical system approaches the intended state of freedom from supply inteffuplion.
continuous operating voltage (U.), {534}. Maximum ms voltage which may be continuously applied to an sPD's mode ofprotection. This is equal to the rated voltage
rl
Control and protective srvitching device (CPS deyice). Switching device (or equipment) capable of operation other than by hand, but with or without local manual operating means. A CPS device provides both functions of contactor and OCPD.
Conlrolgear /see
.Swir, hgeart.
Conventional impulse withstand voltage, The peak value olan impulse test voltage at which insulation does not show any disruptive discharge when subjected to a specified numbel ofapplications ofimpulses ofthis value, under specified conditions.
Co-ordination of electrical equipment. Coffect way ofselecting electrical devices in series to provide safety and continuity of service ofthe installation, taking into account shoft-circuit protection and/or overload protection and/ or selectivity.
Current-carrying capacity of a conductor. The maximum curent which can be carried by a conductor under specified conditions without its steady-state tempemture exceeding a specified value.
Current-using equipment. Equipment which convefis electdcal energy into another form of energy, such
as
light,
heat or motive power. I
Danger. Risk ofinjury to persons (and livestock where expected to be present) ftom:
(i) (ii)
fire, electric shock, burns, arcing and explosion arising from the use ofelectrical energy, and mechanical movement of electrically controlled equipment, in so far as such danger is intended to be prevented by electrical emergency switching or by elect cal switching for mechanical maintenance ofnonelectdcal parls of such equipment.
DC system -
see
Appendix 9.
Departure. Deliberate decision not to comply fully with the requirements ofthis Standard, for which the designer must declare that the resultant degree of safety is not less than that achievable by full colt.tpliance. Design current (ofa circuit). The magnitude ofthe cunent (rms value forAC) to be caffied by the circuit in notmal setvice. Device for connecting a luminaire (DCL). Sys'tem comprising an outlet and a connector provicling a fixed lumillaire with electrical connection to and disconnection from a fixed installation but not providing mechanical suppoft for a
luminaire.
Ditect contqct
(see Basic
protectioll).
Direct heating system. Heating system which generates heat from electrical energy and dissipates it to the room to be heated with a response time being as low as possible. Disconnector. A mechanical switching device which, in the open position, complies with the rcquirements specified for the isolating function. NOTE 1: A disconnector is otherwise known as an isolator. a circuit when either a negligible curent is broken or made" or when oo signillcant change in the voltage across the tenninals ofeach pole ofthe discomector occurs. lt is also capable of caflJing cunents under norrnal cilcuit conditions and carrying for a specified time current under abnonnal conditions such as those of short-circuit.
NOTE 2: A disconaecto. is capable ofopening and closing
Di scrimin qtiotl
(s
ee Sel ect iv i t!)
Distribution board. An assembly containing switching or protective devices (e.g. fuses, circuit-breakers, residual cun'ent operated devices) associated with one or more outgoing circuits fed frorn ore or more incoming circuits,
I
together with teminals for the neutral and circuit protective conductors. It may also include signalling and other control devices. Means ofisolation may be included in the board or may be provided separately.
Distribution circuit. A circuit supplying
a distribution board or switchgear.
A distribution circuit may also connect the origin of an installation to an outlyirg building or separate installation, rr hen it is somelunes called a 'ub-rrain. Distributor. A person who distributes electricity to consumers using elect cal lines and equipment that he/she owus Lrr
operates.
Double insulation. Insulation comprising both basic insulation and supplementaly insulatiofl.
--.
27
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Duct, Ducting free Coble ductittg).
Earth. The conductive
mass
ofthe Earth, whose electric potential
at any point is conventionally taken as zero.
Earth electrode. Conductive paft, which may be embedded in the soil or in a specilic conductive medium,
e.g.
concrete or coke, in electrical contact with the Eat1h.
Earth electrode network, {444}. Parr of an earthing arangement comprising only the earth electodes and their intercol]uections.
Earth electrode resistance. The resistance of
an eafih electrode to Eafih.
Earth fault current. A currelt resulting from a fault of negligible impedance between a line conductor and an exposed-conductive-part or a protective conductor
Earth fault loop impedance. The impedance ofthe earth fault cuffent loop starting and ending
at the
point ofeanh
fault. This impedance is denoted by the symbol 2.. I
The earth fault loop comprises the lollowing, starting at the point offault:
-
the circuit protective conductor, alld the consumer's earthilg teminal and eafihing conductor, and
for TN systems, the metallic rctum path, and
lor TT and lT systens, the Earth retum path, and the path tkough the earthed neutml point ofthe transfonner, and the tmnsfomier winding, and the line conductor fi'om the transfomer to the point of fault.
Earth leakage curre\t
(.\ee
Protective conductor arrrent).
Earthed concentric wiring. Awiring system in which one or more insulated conductors are completely surrounded throughout their length by a conductor, for example a metallic sheath, which acts as a PEN conductor'.
Earthing. Connection of the exposed-conductive-parts of an installation to the main earthing teminal of that installation.
Earthing conductor. A protective coflductor coulecting the main earthing terminal of an installation to an earth electrode ol to other means of eafihing.
Electric shock. A dangerous physiologicaJ effect resulting from
the passing
ofan electric cufient through
a human
body or livestock.
Electric vehicle (EV), U22). Any vehicle propelled by an electric motor drawing curent from a rechargeable stomge battery or frour other portable energy storage devices (rechargeable, using energy from a source off the vehicle ;uch as a residential or public electricity service), which is manufactured primarily for use on public streets, roads or highways.
.
Charging equipment. An assembly including one or more charging points. Electric yehicle charging point. The point where the electric vehicle is connected to the fixed installation.
NOTE:
Thc charging point is a socket-olLtlet where the charging cable belongs to the vehicle. oI a connector. where the charging cable is a fixed pafi ofthe electric vehicle supply equipment.
Mode 1 charging. Connection of the EV to the AC supply network utilizing standardized socket-outlets not exceeding l6 A and not exceeding 250 V AC single-phase or 480 V AC three-phase, at the supply side, and utilizing the power and protective earth conductors (according to BS EN 61851- 1). Mode 2 charging. Connection of the EV to the AC supply network utilizing standardized socket-outlets not exceeding 32 A and not exceeding 250 V AC single-phase or 480 VAC three-phase, at the supply side, and utilizing the power ald prctective eafih conductom together with a control pilot function and system ol personnel prctection against electric shock (RCD) between the EV and the plug or as pafi of the in-cable control box. Mode 3 charging. Connection of the EV to the AC supply network utilizing dedicated elect c vehicle supply equipment where the control pilot function extends to control equipment in the electric vehicle supply equipment, pen'r]anently connected to the AC supply netwolk.
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Mode 4 charging, Connection of the EV to the AC supply netu,ork utilizing an olf-board cliatgcr where the control pilot function extends to equipmelt permanently conr.rected to the AC supply.
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Vehicle connector. Pafi ofa vehicle coupler integral with. or intended to be attached to, the flexjble cable connected to the AC supply network (mains). Vehicle coupler. Means ofenabling the manual connection of a flexible cable to an EV for the purpose
of
charging.
NOTE:
A vehicle coupler consists of two pafts: a vehicle connector and
a
Electrical circuit for safety seryices. Electrical circuit intended to be used
l'ehicle inlet. as part
of an electrical supply system
for safety services.
Electrical equipment (abbr: Equipment), Any item for such puposes as gelemtion, conve$ion, transmission, dist bution or utilization of electrical energy, such as machines, transfonners, apparatus, measuling instruments, protective devices,
wi
ng systems, accessories, appliances and luminaires.
Electrical installation (abbr: Installation). An assembly ol associated electrical equipment having co-ordinated charactedstics to
fulfil specific purposes.
Electrical source for safety services. Electrical source intended to be used as paft of an elect cal supply system for safety senrices.
Electrical supply system for safety services. A supply system intended to maintail the opemtion ofessentiaI pafis
ofan elechical installation and equipment:
(i) (ii)
for the health and safety of persons and livestock, and to avoid damage to the environment and to other equipment.
NOTE:
The supply system includes the source and the circuit(s) up to the teminals ofthe
elecl
cal equipmcnt.
Electrically independent earth electrodes. Eafih electrodes located at such a distance ftom one another that the maximum curaent likely to flow through one ofthem does not significanlly afl'ect the potential ofthe other(s).
Electrode boiler (or electrode water heater). Equipment for the electrical heatirg of water or electrolyte by the passage
ofau electric cuflent between electrodes immersed in
the water or electrolyte.
Electronic convertor (static convertor). A convertor having no movil.Ig parts and notably using semiconductol' rectifiers. Emergency stopping. Emergency switching intended to stop an operation. Emergency switching. An operation intended to remove, as quickly as possible, danger, which may have occumed unexpectedly.
Enclosure. A part providing protection of equipment against ceflail extemal influences and in alty direction providing basic protection.
Energy Efficiency. (Appendix l7) Efficiency measures (EM). Level of implementation of measrues to improve eoergy efficie[cy of an electical installation.
Load shedding. Approach where the elect cal loads are switched otf for variable periods of time to optimiTe demand.
Metering. Applying a device measudng energy or other consumption. Equipment
(see
E/ectrical equipment).
Equipotential bonding. Electrical connecrion maintainlng various exposed-conductive-pafis and ertraneouscolductive-pafts at substantially the same potential. (See also P7?/eclive ecltripotential bonding) Escape route, Path to follow for access to a safe area in the event ofan emelgency.
Exhibition. Event intended for the purpose of displaying and/or selling products etc., which suitable location, either
a
can take place in any
room, building or temporary structure
Exposed-conductiye-part. Conductive part ofequiprrent which can be touched and which which can become live under fault conditions.
is
not normally Jive. but
29
External influence. Any influence extemal to an electrical installation which affects the design and safe operation
ofthat installation.
Extralow voltage (see Voltage, noninal). Extraneous-conductive-part. A conductive part liable to introduce lorrning part ofthe eiectrical insrallation.
a
potential, generally Earth poteltial, and not
Fairground. Area where one or more stands, amusement devices or booths are erected for leisure use. Fault. A circuit condition in which current flows through an abnormal or unintended path. This may result frorr an insulation failure or a bridging ofinsulation.
NOTE:
Conventionally. the impedance between live conductors or between live conductors and exposed- or extlaneousconductivc parts at the fault position is considered negligible.
Fault current, A clrrent resulting from
a
fault.
Fault protection. Protection against electric shock uuder single fault conditions.
NOTE:
For low voltage installations, systems and equipment, fault protection generally corresponds to protectiol against inditect contact, mainly with regard to failure ofbasic insulation. lndircct contact is "contact of pelsons or livestock with exposed,conductive-parts which have become live under fault conditions,,.
Final circuit. A circrtit connected directly to current-using equipment, or to a socket-outlet or socket-outlets or other outlet points for the connection ofsuch equipment. Fixed equipment. Equipment designed to be fastened to a support or otherwise secured in a specific location.
Flexible cable. A cahle whose structure and materials make it suitable to be flexed while in service.
Flexible sheet heating element. Heating element consisting of sheets of electrical insulation laminated with electrical resistance material, or a base material on which electrically insulated heating wires are fixed. Flexible wiring system. A wiring system designed to provide mechanical flexibility in use without degradation the electrical components.
of
Follow current interrupt rating, {534} 1/f, Prospective shofi-circuit current that an SPD is able to interxpt without operation ofthe OCPD.
Functional bonding conductor! {444}. Conductor provided for functional equipotential bonding. Functional earth. Earthing ofa point or points in
a system or in an installation or in equipment, lor putposes other than electrical safety, such as for proper functioning ofelectrical equipment.
Functional extra-low volfage (FELV). An extralow voltage system in which not all ofthe protective
measures
requircd for SELV or PELV have been applied,
Functional switching. An operation intended to switch 'on'or paft ofan installation for normal operating purposes.
'off'or vary the
supply ofelectdcal energy to all or
Fuse. A device which, by the melting ofone or more ofits specially designed and proportioned components, opens the circuit in which it is insefied by breaking the curent when this exceeds a given yalue for a sufficient time. The fuse comprises all the pafis that lorm the complete device. Fuse carrier. The movable part ofa fuse designed to carry a fuse link. Fuse element. A parl
ofa fuse designed to melt when the fuse operates.
Fuse link. A pafi of a fuse, including the fuse element(s), which requires replacement by a rew or renewable fuse link after the fuse has operated and before the fuse is put back into service.
Fused connection unit. A device associated with the fixed wiring of an installation by which appliances tray be connected, and having provision for a replaceable cartridge fuse link. Gas installation pipe. Auy pipe, not being a sewice pipe (other than any part of a sewice pipe comprised in a mary meter installation) or a pipe comprised in a gas appliance, for conveying gas for a particular consumer and including any associated yalve or other gas fitting.
p
Harmonized Standard. A standard which has been drawn up by common agreemenr between national standards bodies notified to the European Commission by all member states and published under national procedues. Hazardous-live-part. A Jive part which can give, under cefiain conditions of extemal influence, an electric shock.
Heating cable. Cable with or without
a shield or a
metallic sheath, intended to give offheat for heating purposes.
Heating-free area. Unheated floor or ceiling area which is completely covered when placing pieces of flrrniture or kept free for built-in furniture. Heating unit. Heating cable or flexible sheet heating element with rigidly fixed cold tails or teminal fittings which are connected to the terminals
ofthe electrical installation.
High-density livestock rearing. Breeding and rearing of livestock for which the use of automatic systems for life support is necessary
NOTE:
Examples ofautomatic
life support systems
are those for ventilation, feeding
ard air conditioning.
High \oltage /se. lolrage. naminal). Highway. A highway means any way (other than a waterway) over which there is public passage and includes the highway verge and any bridge over which, or tunnel through which, the highway passes.
Highway distribution board. Afixed shucture orunderground chamber, located on a highway, used as a distribution point, for connecting more than one highway distribution circuit to a common odgin. Street fumiture which supplies more than one circuit is defined as a highway distribution board. The connection of a single temporary load to an item of street fumitue shall not in itself make that item of street fumitwe into a highway distlibution board.
ll circuit connecting the origin of the installation to a remote highway distribution board or items ofstreet fumiture. It may also connect a highway distribution board to street fumiture.
Highway distribution circuit. A Band
Highway power supply. An electdcal installation comprising an assembly of associated highway distribution circuits, highway distribution boards and street fumitule, supplied from a commol origin.
Ilouseboat. Floating decked structue which is designed or adapted for use kept in one place on inland water.
as a place
of permanent residence often
Impulse current (Ii-p), {534}. Aparameter used for the classification test for SPDs; it is defined by tfuee elements, a cu-rent peak value, a charge Q and a specific energy
WR.
Impulse withstand voltage, {534}. The highest peak value of impulse voltage of prescribed fotm and poladty which does not cause breakdown ofinsulation under specified conditions.
Indirect contact
(see Faull
protection).
Inspection. Examination ofan electrical installation using all the
Installation
(see
Electrical
I
senses as appropriate.
installation).
Instructed person (electricallD. Person adequately advised or supervised by
I
a
skilled person (as defined) to enable
that pe$on to perceive risks and to avoid hazards which electdcity can create. NOTE 1: The term "(electrically)" is assumed to be present where the tenn 'iNtructed person' is used throughout BS 7671. NOTE 2: Regulation 16 ofthe Electricity at Work Regulations 1989 requires persons to be competent to prevent danger and injury. The HSE publication HSR25 provides guidance on this.
Insulation. Suitable non-conductive material enclosing, surounding or supporting
a conductor.
Insulation co-ordination, {534}. The selection of the electric strength of equipment in relation to the voltages which can appear on the system for which the equipment is intended, taking into account the service environment and the charactedstics
ofthe available protective devices.
lsolation. Function intended to make dead for reasons ofsafety all or a discrete section ofthe electrical by separating the electrical installation, or section thereof, from every source ofelechical energy.
installation
I
Isolator. A mechanical switching device which, in the open position, complies with the requirernents specified for ihe isolating function. An isolator is otherwise known as a disconnector. Lad.der (see Cable ladder). Leakage current. Electdc current in an unwanted conductive path under nomal operating conditions.
Leisure accommodation vehicle. Unit of living accommodation for temporary or seasonal occupation which may meet requirements for construction and use ofroad vehicles.
Lightning protection zone (LPZ), {534}. Zone where the lightning electromagnetic environment is defined.
31
Line conductor. A conductor
than a neutral transmissioo of electrical energy other AC system for the of al of a DC ductor co j.j the equivalent
ir't i"'* "^;^';;;;' specified in the Regulations
conductor, a pfotective conduclor
utto ,,'"uot
,Vrt"a ,nL..t o,fl.,*ise LiYe conductor (see Lite Part)'
I
l
use' including pafi intended to be energized in normal Live part. Aconductor or conductive
h\
I
a
neutal conductor but'
con\ enlion, nol a PE\'l conductor'
Low voltage lsee Voltage, nontinal)'
devices or more low voltage switching
assemblll Combinal'.",.1^"1*" wilh all the intemal Low voltage switchgear and controlgear signalling protective "gututlng equipment' toselher \ ith associared control' mea-suring'
;;;:;r;,i.'r i*'"*""ii"n '"i "i"*ut "l::i;i::,
pans rsee BS
t*
'-143e-r)'
themselves' Luminaire.Equipmentwhichdistributes.filtersortransformsthelighttransmittedfromoneormorelampsand p^rotecting the lamps, but not the lamps n*-g
,r"...ruriio, .rpf"nirg, *iir' tr"
pun,
which includes all tt
" and rvhere necessary, ci'c'it uu^itiu'1"'"i"g""i"t
NOTE:
"nd supply' ti'eans for connecting them to the
emitting diodes' Lamps includes devices such as Iight
an LSC comector' providing A means' comprising an LSC outlet and Luminaire supporting coupler (LSC)' afixedwiring installation' ftom olola't;;;;*";i;:;iion"to unddircon mechanicat suppofi fo,
at
minutre
"ction
Mainearthingterminal.TheterminalorbarprovidedfoJthe,connectionofprotectiveconductors,including of earthing' fJ; i'nctional earthing' if anv' to the means #;;;";; protective bonding conductors,
Maintenance.Combinationofalltechrricalandadministrativeactions,includingsupervisionactions,intendedto can perfotm a required function. in, or,.,to," lt to, u ,tut" in which it retain an item
Marina.Facilityfolmooringandseruicingofpleasurecraftwithfixedwhar.ues.jetties,pie$olpontoonallangernents pleasure craft' capable ofbelthing one or more and non-electdcal parts of refurbishment or cleaning of lamps replacement, The maintenance. Mechanical equipolent, Plant and machinery'
Medicallocation,{710}.Locationintendedforpurposesofdiagnosis.tleatmenlinclrrdingcosmeticheatlTent' n.ronitoring and care ofpatients'
.Applietlpart.Pafiofmedicalelecfuicalequipmentthatinnomalusenecessarilycomesintophysicalcontact ot un Mf syst"m to petfom its function' ul with the patient for
.
"ffit"'t discontinuity (failure) pafis are irtended to be used and where applied no where location Medical Group 0. ofthe supply cannot cause danger to life'
.
Group
1.
(failure) ofthe supply does not represent Merlical location where discontinuity
*O "-itrri"p"ii""t
. .
a
threat to the safety
parts are intended to be used:
"pplied
extemallY
where Group 2 applies' invasive\ to any pafi ofthe body except
discontinuit; {failure) of pan" are intended Io be used' and where Grouo 2. Medical locarion where applied
;.;o'; .rn.uur. dungtt to lile' in applicarions . intracardiacProcedures . \ ilal treatlnellls and surgical operation"' NOTE:
such as:
placed within the heart of a whereby an electrical conductor is An intracardiac procedure is a procedule the patient's ii"'f,iun,.u"fI .ooarctor being accessible outside patienr or is likely 10 c"In" i"a i".,"i -Un or electrodes pacing includes insulated wires such as cardiac body ln this context' ""ta'"t"r fluid'
"" "ft"in*l tubes fllled with conducting intracardiac ECG electrodes' or insulated
transferring
pafi or Electdcal equipmen^t having an applied is Medical electricat equipment (ME equipment)' which patient and to or from the
t""tgy transfer energy to or from the patienr or detlai"rig"utf' parlicular supply mains' and (a) provided with not more than one connection to a
used intended by the manufacturer to be of a patient' or ' in the diagnosis, fteatment or monitoring injury or disability' ' for compensation or alleviation ofdisease' enable the manufactuler that are necessary to those accessories as defined by the includes eqlipmelt ME NOTE: nomal r.rse of the ME equipment'
(b)
][edical electrical slstem r\IE slstem). Combination. as specified b] rhe manut'ac rer. of irems of equipment. ai ieasi ..,1e oi,-. h:ch is medical electrical equiprnent to be interconnected b.v functional connectiot'l rrr b) use ofa muhiple socket-outlet.
NOTE:
The svsten, includes those accesso es which are needed for operating the system and are specified by the manufacturer.
\Iedical IT system. IT electrical system fi.rlfilling specific requirements for
NOTE:
Patient. Living being (person or animal) undergoing
NOTE:
r.nedical applications.
These supplies are also known as isolated power supply systems. a
medical, surgical or dental procedure.
A person under treatment lor cosmetic purposes may be considered a patient.
Patient enyironment. Any volume in which intentional or unintentional contact can occur between a patient ar]d pafis of the medical electrical equipment or medical elechical system or between a patient and other persons touching pal1s ofthe medical electrical equipment or medical electrical system.
1: NOTE 2: NOTE
For illustration see Figure 710.1.
This applies when the patient's position is predetennined; ifnot, all possible patient positions should be consideled.
\leshed bonding netyiork (MESII-BN), 1444\. Bonding network in \xhlch al\ assaciated equipment frames, racks a\d rasl\e\s a\( us\a\\) $eDC !o'we\ \e!.I\\ cod\c\or are \onde{ toget\er 6s \Ne\\ as a\ 1\\\i1!\e Do\1ts \o i\e CBN and may have the form of
NOTE:
a
mesh.
A MESH-BN improves the pedonnance ofa comnton bonding [etwork.
-Vinimum illuminance. Illuminance lor emergency lighting at the end of the rated opemting time
Minor works. Additions and alterations to an installation that do not extend to the provision ofa new circuit.
NOTE:
Examples include the addition ofsocket-outlets or lighting points to an existing circuit, the relocation ofa light switch etc.
Mobile and offshore installations. Installations used for the exploration or development of liquid or
gaseous
hydrocarbon resources.
Mobile equipment (portable equipment (deprecated)). Electrical equipment which is moved while in operation or which can easily be moved ftom otre place to another while connected to the supply.
Mobile home. A transportable leisure accommodation vehicle which includes means for mobility but does not meet the requirements for construction and use ofroad vehicles.
Motor caravan. Self-propelled leisure accommodation vehicle,
used for toudng, that meets the requiremenls for the
constluction and use ofroad vehicles. vehicle, or designed and built on an existing chassis, with or without the driving cab, the accommodation being either fixed or dismountable.
NOTE: It is either adapted from a series production
Neutral conductor. A conductor connected to the neutral point of a system and contributing to the transmission of electrical energy. The term also means the equivalent conductor of an IT or DC system unless otherwise specified in the Regulations and also identilies either the mid-wire ol a three-wire DC circuit or the earthed conductor of a two-wire earthed DC circuit. Nominal discharge current (In.pd), {534}. A parameter used for the classification test for Class I SPDs and fot preconditioning of an SPD for Class I and Class II tests; it is defined by the crest value of cunent through an SPD, having a current waveform of 8/20. Nominal yoltage (see Voltage, noninal). Non-compliance. A non-conformity that may give rise to danger
Non-flame propagating. Liable to ignite as a result of an applied flame but, after the flame is rertoved, does not propagate flifiher and extinguishes itself within a limited time. Obstacle. A part preventing unintentional contact with live pafis but not preventing deliberate contact.
Open-circuit voltage under standard test conditions
Uo" src. Voltage under standard test conditions across an
unloaded (open) generator or on the DC side ofthe convertor.
Operating and maintenance gangway, {729}. Gangway providing
access to
facilitate operations such
as
switching,
controlling, setting, observation and maintenance of electdcal equipment.
33
Ordinary person.
Person who is neither a skilled person nor an instucted pe$on'
origin of an installation.
installation' The position at which electrical energy is delivered to an electrical
originofatemporaryelectricalinstallation.Pointonthepermanentinstallationolothelsoulceofsupplyfrom
whifh electrical energy is delivered to the tempomry electrical installation oyercurrent. A curent exceeding the mted value. For conducto$
the lated value is the
curent-carying capaciry
overcurrentdetection.AmethodofestablishingthattheValueofcurrentinacircuitexceedsapredetermined value for a specifled length of time. an electric circuit in overcurrent protective device (ocPD). Device provided to interrupt cunent in the electric circuit exceeds
a
case the conductol
predetermined value for a specified duration'
NoTE:TableA53.lprovidesinlbrmationregardingthediffelentdevicescorespondingtothemaingenericfunction' current. An overcunent occuring in a circuit which is electrically sound.
oyerload
PartialselectiYity.Selectivityuptoagivenovelcurentlowelthanthebleakingcapacityofthedownstrcamdevice' PEL.Aconductorcombiningthetirnctionsofbothaplotectiveearthingconductolandalineconductol' which PELV (protectiye extra-low yoltage). An extra-low voltage system for SELV requirements but which otherwise satisfies all the
is
not electrically sepamted from Earth'
PEM.Aconductorcombiningthefunctionsofbothaprotectiveearthingconductorandamidpointconductor protective conductor and neutral conductor' PEN conductor. A conductor combining the functions ofboth
Persot
(see Skilled,
Phase conductor
/.s
lnstructed' Ordinat!) ee
Line cond ctot).
or other floating craft used exclusively for spolt Pleasure craft. Any boat, vessel, yacht, motor launch, houseboat or leisure. a socket-outlet' and incorporating means for Plug. Accessory having pins designed to engage with the contacts-of cable' the Electrical connection and mechanical retention of a flexible point (in wiring). A temination ofthe fixed wifirg intended fol the connection ofcurent-using equipment
Portable equipment (see Mobile equipment) powertrack. A system component, which is generally
a
linear assembly ofspaced and supported busbars, ploviding
electrical connection olaccessories'
Powertracksystem(PTsystem).Anassembl}of\yStemcomponentsincludingapowemackbywhichaccessories the powedrack. -o." poi"ts (predetermined or otherwise) along
may be connected to ur, ara"t.iaul ,uppry ui on'" o,
NOTE:
The maximum current mting
ofa powertrack system is 63A
Prefabricatedwiringsystem.WiringsyStemconsiStingofwiringsectionsincolpolatingthemeansofinterconnection a giren system, and incorporating installation couple$ designed to allow sections to be c;;;ct"d tog.th", to"fo.,., confoming to BS EN 61535.
'fhe value of overcunent at a given point in a circuit resulting from a fault Prospective fault current (Ip).
of
,"grigiuL.impedancebetweenti,"coodu"to,shuuingadifferenceofpotentialundernormaloperatingconditions.
orLat*""n
u
iiua
and an exposed-conductive-pafi'
"onductor
Protectivebondingconductor.Protectiveconductorprovidedforprotectiveequipotentialbonding. Protectiveconductor(PE).Aconductorusedforsomemeasulesofplotectionagainstelecfficshockandintended fo1 connecting together any ofthe following palls:
1i,) Erposed-conducti\e-Parts
(ii) Extraneous-conductive-parts (iii) The main earthing terminal (iv) tanh electrode(s) (v) The earlhed point ofthe source, or an artiflcial neutral' conductor' such as leakage curent or Protective conductor current. Electric current appearing in a protective electric curent resulting from an insulation lault'
ProtectiYe earthing, Earthing ofa point or points in a system or in an installation or in equipment for the purposes -.i jafety. Protective equipotential bonding. Equipotential bonding for the pulposes of safety.
Protectiye multiple earthing (PME). An eafthing arangement, found in TN-c-s systems, in which the supply r3utral conductor is used to corulect the eafihing conductor of an installation with Eafth, in accordance with the :.ectricity Safety, Quality and Continuity Regulations (ESeCR) (see also Figure 3.9). Protective separation. Separation olone electric circuit from another by means ti) double insulation. or
iil , iii) t
ol
basic insulation and electrically protective screening (shielding), or
reinforced insulation.
P\. {712}, Solar photovoltaic.
'
PV AC module. Integrated module/convertor assembly where the electrical inteface teminals are AC only.
\o
access is provided to the DC side.
' P\ array. Mechanically :.rn-
.
I
I
and electrically integrated assembly ofPV modules, and other necessary components, to
a DC power supply unit.
PV array cable. Output cable ofa PV array.
'P\-arrayjunctionbox.EnclosurewherePVstringsofanyPVarayareelectdcallyconnectedandwheredevices .'an be located.
' . ' . '
PY cell. Basic PV device which can generate electricity when exposed to light such as solar radiation. PY convertor. Device which converts DC voltage and DC curent into AC voltage and AC current.
I
PV DC main cable. Cable connecting the PV gererator junction box to the DC temrinals of the PV convertor
I
PY generator. Assembly of PV arays.
PV generator junction box. Enclosure wherc PV arrays are electrically connected and where devices can be located.
. . '
P\r installation. Erected equipment ofa PV power supply system. PV module, Smallest completely environmentally protected assembly of interconnected pV cells. PV string. Circuit in which PV modules are connected in series, in order for a PV anay to generate the required
output yoltage.
.
PV string cable. Cable connecting PV modules to fo1m a pV stdng.
'
PV supply cable. Cable connecting the AC tenninals electrical installation.
of the PV convertor to a distribution circuit of
the
Rated current. Value of curent used for specification purposes, established for a specified set of operating .ondrlions ofa component. de\ ice. equipmenl or system.
Rated impulse withstand voltage level (U,,.), {534}. The level of impulse withstand voltage assigned by the manufacturer to the equipment, or to part of it, characterizing the specified withstand capability of its insulation against overuoltages.
NOTE:
For the purposes
ofBS 7671, only withstand voltage between live conductors and Eafth is considered.
Reduced low voltage system. A system in which the nominal line-toline voltage does not exceed 110 volts and the nominal line to Earth voltage does not exceed 63.5 volts.
Reinforced insulation. Single insulation applied to live parls, which provides a degree ofprotection against electdc shock equivalent to double insulation under the conditions specified in the relevant standard. The term 'single insulation'does not imply that the insulation must be one homogeneous piece. It may compdse two or more layers \\ hich cannot be tested singly as supplementary or basic insulation.
Reporting. Communicating the results ofperiodic inspection and testing of an electrical installation to the pe6on ordering the work.
---
t
Residences and other locations belonging to agricultural and horticultural premises. Residences and orher iocations which have a conductive connection to the agricultural and horticulturai premises by either protecrir e conduclols of the same installation or by extraneous-conductive-parts.
NOTE:
Examples ofother locations include offices, social rooms, machine halls, u,orkrooms. gar-ages and shops.
Residential park home. A factoq/ produced relocatable dwelling designed for pennanent residence which may be used for leisure purposes.
Residual current. Algebraic sum of the cuffents in the live conductors of a circuit at a point in the electical installation. Residual current device (RCD). Mechanical switching device designed to make, cary and break curents ulder norlnal service conditions and to cause the opening ofthe contacts when the residual curent attains a given value under specifi ed cotditions. NOTE 1: A residual cunent device can be a combination of various scparate eiements designed to detect and evaluate the r'esidual crincnt ald to make and break currclt. NOTE 2: RCD includes devices such as RCCB. RCBO. CBR and MRCD. NOTE 3: MRCD is a modular residual cunent device.
Residual current operated circuit-breaker with integral overcurrent protection (RCBO). A residual curent operated switching device designed to perlorm the functions of prctection against oyerload and/or shon-circuit.
Residual current operated circuit-breaker lyithout integral overcurrent protection (RCCB). Aresidual cuffent operated switching device not designed to perfonn the functions ofprotection agaiust overload and/or short-cir-.cuit. Residual operating current. Residual cunent which causes the RCD to operate under specified conditions. Resistance area (for an earth electrode only). The surface area ofground (around an earth electode) on which a signilicant voltage gradiert may exist. Response time. The time that elapses between the failure ofthe normal power supply and the ability ofthe auxiliary power supply to energize the equipment.
Restrictive conductiye location (see Co dtlctitlg locatiofi uith restricted fioyement). Ring final circuit. A linal circuit arranged in the form ofa ring and comected to a single point of supply. Safety service. An electdcal system for electuical equipment provided to protect or walr persons in the event of hazard. or essential to their evacuation ftom a location.
a
Sauna. A room or location in which air is heated, in service, to high temperatures where the relative humidity is normally low, rising only for a shofi period of time when water is poured over the heater.
SELV (separated extralow voltage). An extra-low voltage system which is electrically separated from other systems in such a way that a single fault cannot give rise to the risk ofelectric shock.
fio[r
Earth and
Selectivit). Co-ordination of the operating characteristics of two or more protective devices such that, on the incidence ofan overcurrellt ol lesidual cufient within stated limits, the device intended to opemte within these limits does so, while the other(s) does (do) not.
NOTE:
Fundamentally. selectivity is the ability ofa plotective device to opemie in prelerence to anolher protective delice in selies.
Partial: Selectivity llp to a given ovelculrent lower than the breaking capacity ofthe downstream device. Total: Selectivity for all overcurents up to the value ofthe breaking capacity ofthe dowNtrean device.
Shock (see Electric shock). Shock current, A current passing through the body of a person or livestock such as to cause electric shock and having characteristics Iikely to cause dangerous effects.
Short-circuit current. An overcun'ent resulting fi'om a fault of negligible in.rpedance between live conductol's having a difference in potential under normal operating conditions. Short-circuit current rating 1.aa*, {534}. Maximum prospective shofi-circuit cu[ent ftom the power system for which the SPD, in conjulction with the OCPD specified, is mted. Isc STC, {712}. Shot-circuit current of a PV module, PV string, PV array or PV gererator under standard test conditions.
Short-circuit current under standard test conditions
36
I
I
Short-circuit protective device (SCPD). Device intended to protect
a
circuit or parl ofa circuit agairst shoft-circuit
currents by intelTupting them.
NOTE:
Table 453.1 provides information regarding the different devices corrcsponding to the
Show Display or presentation in any suitable location, either
a roon1,
nain generic function.
building or tempomry structure.
Simple separation. Separation betweell cjrcuits or between a circuit and Earth by lneans ofbasic insulatiorl. Simultaneously accessible parts. Conductors or colductive pal1s which can be touched simultaneously by or. in locations specifically intended for them, by livestock
NOTE:
a
person
Simultaneously accessible parts may be: live pafts, exposed-conductive-palts. exttaneous-conduclive-parts, protective conducrors or eanh electrodes.
to the nature of the electrical work to be is able to perceive risks and avoid hazards practical and who skills, undertaken, adequate education, training and rvhich electricity can create. NOTE 1; The te1m "(electrically)" is assumed to be present where the teflr 'skilled person' is used throtlglrout BS 7671. Skilled person (electricalty). Person who
possesses, as appropriate
NOTE 2: Regulatjon 16 of the Electricity at Work RegulatioDs 1989 requires peNons to be competent to prevent danger and injury. The HSE publication HSR25 provides guidance on this.
Socket-outlet. A device, provided with female contacts, which is intended to be installed with the fixed wiring, and intended to receive a plug. A luminaile track system is not regaded as a socket-outlet system. SPD disconnector. Device for disconnecting an SPD, or part ofan SPD, from the power systen.
NOTE:
I
This disconnectjng device js not required to have isolating capability for safety purposes. lt is to prevelt a peNistelt fault on the system and is used to give an indication of an SPD'S failure. Disconnectors can be irtemal (built i]1) or extcmal (required by the manufacturer). There may be more than ore discollnector function. for example an ts overcurrent protection function and a thennal plotection fuoction. These functions nlay be in separate
u
Spur. A branch from a ring or radial final circuit. Stand. Arca or temponry structure used for display, nTarketing or sales.
Standard test conditions (STC). Test conditions specified in BS EN 60904-3 for PV cells and PV modules. Standby electrical source. Elect cal source intended to maintain, for reasons other than safety, the supply to electrical installation or a palt or pafis thereof, in case ofintenuption of the normal supply.
an
Standby electrical supply system. Supply system intendedto [raintain, forreasons otherthan safety, the functioning of an elect cal installation or a part or pafts thereoi in case of inteffuption of the nonnal supply. Static convertor. A convefior having no moving parts and notably using semiconductol fectifiel.S.
Stationary equipment. Electrical equipn,ent which is either fixed or which has provided with a canying handle.
a n]ass
exceeding 18 kg and is not
Street furniture. Fixed equipn.rent located on a highway.
Supplementary insulation. Independent insulation applied in addition to basic insulation fol far'rlt protection.
S\pplier
(see Di s tri brtor ).
Surge current, {534}. A transient wave appearing as a[ ovefcufient caused by
a
lightning electromagnetic impu]Se.
Surge protective device (SPD), {534}. A device that is intended to limit transient oYervoltages ard divefi sutge cu[ents. It contains at least one non-linear component. Srvitch, linked. A switch the contacts ofwhich are so arranged as to make or break all poles simultaneously or in definite sequence.
a
Switch-disconnector. A switch which, in the open position, satisfies the isolating requirements sPecified for
a
disconnector
NOTE;
A switch-disconnector is otherwise known as an isolating switch.
itchboard, An assembly ofswitchgear with or without instruments, but the term does not apply to gtoups oflocal in final circuit>. 'rritches srritchgear. An assetnbly of mai[ and auxiliary switchillg equipmeut for operation, Iegulation, plotection or oll]el Sn
corrtrol of an electdcal installation.
37
System. An electrical system colsisting ofa single source or multiple sources ruming in parallel ofelectrical energy and an installation. See Part 3. For cefiain purposes of the Regulations, types of system are identified as follows, depending upon the relationship ofthe source, and of exposed-conductive-pafis ofthe installation. to Earth:
-
TN system. A system having one or more points of the source of energy directiy earthed, the exposedconductive-pafis ofthe installation being connected to that point by protective conducton.
-
TN-C system. A system in which neutral and protective functions are combired in a single conductor throughout the system.
-
TN-S system. A system having separate neutral and protective conductors throughout the system (see Figure 3.8).
-
TN-C-S system. A system in which neutral and protective functions are combined in a single conductor
ir
paft ofthe system (see Figure 3.9).
TT system. A system having one poirt of the source of energy directly earthed, the exposed-conductivepalls of the installation being connected to eafih electrodes electrically independent of the eartb electodes olthe source (see Figure 3.10).
- IT system.
A system having no direct connection between live pats and Earlh, the exposed-conductiveparts ofthe electrical installation being eathed (see Appendix 9 Figure 9C).
-
Multiple source and DC systems -
see
Appendix 9.
Temporary electrical installation. Electrical instal[ation erected for longer required lor that puryose.
a
particular purpose and dismantled u,hen no
Temporary overvoltage (U1e1,), {534}. A fundamental frequency overvoltage occuring on the netrvork at a given location, of relatively long duration. NOTE 1: TOVs may be caused by
1'aults inside the
LV system (Urovlv) or inside rhe HV system (U1e1, s1,)
NOTE 2: Temporary over,/oltages. typically lasting up to several seconds, usually originate from switching opcrations or faults (for example, sudden load rejection, single phase faults, etc.) and/or from non-linearity (feiroresonance effects. harmonics, etc.)
Temporary structure. A unit or paft of a unit, including mobile po able units, situated indool.S or outdoors, designed and intended to be assembled and dismantled.
Temporary supply unit. An enclosure containing equipment for safely from an item of street fumiture.
the purpose
oftaking
a
temporary elect cal supply
Testing. Implementation of measures to assess an electrical installation by means of which its effectiveness is proved. This includes ascertaining values by means of appropdate measuring instruments, where measured values are not detectable by inspection.
Thermal storage floor heating system. Heating system in which, due to a limited charging period, a restricted availability of electrical energy is converted into heat and dissipated mainly through the surface ofthe floor to the room to be heated with an intended time delay.
Total selectivity. Selectivity for all overcurrents up to the value ofthe breaking capacity ofthe downstream device,
Triplen harmonics. The odd multiples ofthe
3'd
harmonic ofthe fundamental frequency (e.g. 3.d,9'1,, 15,h,21")
Trunking lsee Cable trunking). Verification. All measures by means ofwhich compliance ofthe electdcal installation with the relevant requirements
ofBS 7671
are checked, comprising inspection, testing and cefiification.
Voltage, nominal. Voltage by which an installation (or part of an installation) is designated. The lollowing ranges of nominal voltage (rms values for AC) are defined:
-
r
NOTE:
Extra-low. Not exceeding 50 V AC or 120 V ripple-free DC, whether between conducton or to Earth.
I
I
Low. Exceeding extra-low voltage but not exceeding 1000 V AC or 1500 V DC between conductors, or 600 V AC or 900 V DC between conductors and Earth. High. Noulally exceeding low voltage. The actuaLvoltage ofthe installation may differ fronr the nomioal value by a quantity withill normal tolerances. see Appendix 2.
38
,
\bltage, reduced
(see Reduced
low voltqge s!-stem).
Voltage band Band
I
Band I covers:
- installations where protection against electric shock is provided under certain conditions by the value ofvoltage;
-
irstallations where the voltage is limited for operational reasons (e.g. telecommunications, signalling, bell, control and alam installations).
Extra-low voltage (ELV) will nonnally fall within voltage Band I-
Band
II
contains the voltages for supplies to household and most commercial and industrial installations. Low voltage (LV) will notmally fall within voltage Band II.
NOTE:
Band
II
Band
lI
voltages do not exceed 1000
VAC
rms or 1500
V DC
\bltage protection level (Uo), {534}. A parameter that chamcterizes the performance of an SPD in limiting the voltag-e across its terminals, which is selected fiom a list ofpreferred values; this value is greater than the highest value ofthe treasured lin.riting voltages.
Wiring system, An assembly made up of cable or busbars and pafis which secute and, if necessary enclose the cahle or busbars.
Fig 2.1
-
lllustration of earthing and protective conductor terms (see ChaPter 54)
1,2,3,1 1
2 3
Protectlve conductors ckcult prolective conductor main protective bonding conductor
4
supple;entary prol€ctive bonding conductors {where requned)
B
main earthlng terminal
c T E
exposed-conductive-parl extEneous.conductlve-Part main metallic water pipe {extraneous'conductive_Part) earth €lectrode Gr and lT systems) othar means ofearthing (TN systoms)
39
SYMBOLS USED IN THE STANDARD Symbol
Nleaning
Eranple
C
rating factor - general
Appx 4 sec
CRL
calculated risk lelei used to deternine if protcction againsi ft ansienr overvoltages of almospheric origin is rcquired.
441.5
rating factor for ambient
Appx ,l scc
rating facior for circuits budcd ir the ground
Appx 4
sec 3
Cd
rating factor for depth ofburial
Appx 4
sec 3
Cf
mting factor for semi-enclosed fuse to BS Jf)J6
Appx 4 sec
3
C"
rating factor for groupirg
Appx 4 sec
3
Ch
rating factor for higher hannonic currents in line
Appx 4
Ci
Eting factor for conductors cmbedded in themal insulation
CA
CC
Cmnr CS
Ct
Symbol 3
3
part ofthe eath fault curent ii the high voltage system that flows rhough the earthing arrangement of the transfonner substation
IE
the fault cLment that flows through thc earthirg armngemeflt of the exposcdconductive parts ofthe equipment ofthe low voltagc installation during a period when there is a high voltage fault and a first fault in lhe low voltage installation
142.1.2
lm
ntb hannonic cunent
Appx ,l scc 5.6
limp
selection ofSPDS with rcgard to impulse discharge currenl
53,1.4.4.,1
Itr
ratcd current or cuncnl setting ofprotective device
Table 41.1
Appx 4 sec 3
Ininilnum voltagc factor
4I 1.4.5
Ia,
rated residual operating curren! ofRCD, in ampercs
4lL.5.l
ratiig factor for thcrmal resistivity ofsoil
Appx 4 sec
516.4.202
rating factor for operating
Appx 4 sec 6.1
The nted curent (A) of an asserrbly which is the marimum load current that
Ih
sec 5.6
l
ttu\
it
teInperalure of conductor
DE
IIzk
battery capacity
A721.525
cxternal cable diameter
Appx 4. Table 4A2
ihe sun ofthe continuous
Appx l0
INC
sec 2
conduclors in parallel
frequency in cycles per second an environmental factor,
selected according according to Table 443.1
Hz
Appx
class'gG' utilization category offuscs to 85 88 2'general use
4l1.4.201
class gM' utilization category of tuses to,BS 88--2 motor circuil application
411.4.201
534.4.4.4
Ilr
prospective fault cunent
Appx
Ipk
rated peak withstand current
536.4.201
ISCCR
selection ofSPD5 with regad to the shon-circuit cwent rating
534.4.4.6
sho -circuii current uDdcr
712.,131.I
STC
culTent (gcncml lenn)
Il 411.4.5
lb
desigD current of circr.rit
433.1.1
Ibh
design cun€nt
Ia
cffecl
ofthid
iicluding the
IZ
k
Appx
design current for conductor
It,
neuiral cunent duc to third harmonic currenis
App 4 sec 5.5.2
Ic
charging cunent
A',721.525
mted conditional shot- circuit
536.4.201
lc.'
rared shori-timc !vithstand
.134.5.3
fault cunenr offirst fault
4[
(IT systern)
40
=:,.
-.--
62
6
Appx 4 sec
tabulated culTeot-canying capacity ola cable
cufent-carrying capacity of
a
3
433.1.l
cable for continuous ser"r'icc under the particular iflstallatjon conditions conccmed Izk
the continuous current-carrying
I1
energy let through raiing device
10 sec 2
Ibk
scc 2
standard test conditions
Appx 4 sec 5.5.2
hannonic cunens
Appx l0
selectron ofSPDS widl regard to discharge curent
TSc
cunent causing opemtion of the protective dcvicc witlrin tlre specjfied time.
ofthc protectile
536.,{.202
device for conductor k
6
443.5
The rated cuffent (A) ofa circuit as statcd by the assembly rnanufacturer, lakirg into consideration the ratings ofthe devices within the circuits, thcir disposition and application rated culTenl
hk
gM
is designed to manage and
distribute
cu 'entcanying capacities ofm
f
fxample
Meaning
Appx
10 sec 2
capaciiy ofconductor k
of
431.5.2
l2
currcnt causing effective opcration of fie ovcrload protective device
433.r.1
l
thel]nal conductiviiy
523.9
k
material factor laken from Tdbles 13.1, 51.2 to 51.6
131.5.2
k:ST
energy withstand of cablc
434.5.2
llc.riry
E\ampl€
Svmbol
lleaning
6e risk assessment lengrh 0sn)
]1i.5
t
time (secoDds)
lp
maxrmum permitted nonnal operatirg conductor-
U
voltagc betwcen lines
,ll1.6.4
UC
continuous opcrating voitage.
534.4..1.i
of high voltage
,143.5
of
1ow voltage
441.5
::::1h rkrn) ofhigh voltage -:::::rnuDd .ablc : j :r_rh (km) of low voltagc -::rrround cable
441.5
:::;:: Lrr :.
: -::. drop per anperc pcr r:.:.i:\
e \ oltagc drop per
_::3r: per nretre -::,::r\ e \ oltaqe drof pef
:::::jrL'per
dr
-:::i.cr ol circuits ur
mVA
rcsponsc vahrc
.rr:
system bet!veen exposed-
Appx 4 scc 6
conduclivc-parrs and earrh for thc duration ofthe lauli
sec 6
Uo"
open circuit vohage
Tablc l6A
lnVA'mr
Appx 4
sec 6
Uoc sTC
open-circril !oltage xnder
712.41:l.l.l
Up
vollagc protectjon level ofSPD.
uTov
lemporary orelaohagc. r/j-i4,,
Paf
mted impulsc \lithstand \olragc lcvel. r,-tJ4/'
Tab,c:u3.-l
op pcr a group
Appx
,{ sec 2.3.3.I
443.5
Ur 415.2.2 U0
ofthe IMD
538. t.1
bcd in BS EN 61557-8
iuln ofthc reslstances of
Ul
o
411.5.3
:3rrh electrode and the :-.:J.Ir\ c conduclor connccing .r rhc exposed-conductivc-
: in .
delined as the "rcsislance
-":
442.1.2
:!:mnce ofrhe earthing
412 t.2
:..:rnalion aDd offie low :::Jlc s\sleD neutlal arc
::
volragc al tcst elecn'odc to
larth
I
liblc,lLI
poucr iiequencl st|css volrauc belueeo the ii c conduclor and ihc cxposcd-conducli \ c-pa11s olthc lo\L vollagc equiflrrent of th€ tfanslonn.r subsralion
,1.11.l.l
,l.ll. r.l
poYer lrequcncy stress \ oltrgc bctt'ern thc linc corductor und s
the irnpcdaDcc bctivccn thc lor, \oltage system and an eafihing
ll
thc inrpcd.rrcc lhLrr
oipa
+Q.t.7
llcl
Appr l0
538.t.1
t)lr1oi rhc.x h l:ull l(n)l
rnlpedrl,!a \',ll1.h li
!\t.irr.il
.t
ti
I
i
o
Appx l0
thc impedance of parallel
o
Appx l0 sec:
o
4l1.,1.5
Zk
the
ZN
pedance ofconducror k
ZS
earth lhult loop inpedance
z\
i]npedance
olfloor insulation
o
Appx
: l]lolcctivc equipotenrial : i :Jing
Z',
neutral-eaIth loop inipedance (tT sysiems \l'ith disrributed DeutraloDly)
o
41r.6.1
'
_:irninac of Iinc conductor ofa :.rrbution or final circuit
Appx 6 Geneic
i.inancc of circuit protecri\.e rliuctor (cpc)ofa drsrdbution
Appx
::nal cflcuit. r: rnorlinal cross sectiolal :-.ri-scctional area o1'parallcl ::.rii-sectional arca ::nducior k
of
oftesl
po$er factor (sirusoidal)
li
Appx,l
sec 2
scc 2
sec 6.2
6 Generic
schedlLlc of test results 543.1.3
Appx l0
sec 2
Appx l0 sec:
41
\
l
tr)
the PE conncction :r :nother rci'erence poinl
schedule
sec
I
thc installtltion
442.t.2
:.aflh.
.
scc 2
nonrinul AC rrDs or rq?/. /,.,r DC liDc \oltagc to Eal1h
Z
/.t
r::11.ef dre rystcrr to \rh'ch : : .onneded aDd either
:
IOV
ll
App\
($hen lncasuring insulatioll rcsisiance offloors and walls)
coDdlrcror
rrdcpendun(
insulation rcsistance
-l,l.l. -1.l
voltage inslallation during the fhult
:-rn!emcnts ol the lranslormcr
:.:nance ollhe earthing -r::rr,:cr]1enl of the faDslol.mer
a
i5t4l
oflhc cquipmcnl olrhc low
. :ienl ncLLlral, for low voltage , i:rmi ir $,hich the earlhirg
, r.ilicall)
standard test coDditions
the cxposcd-condLLctive-paft
s
.-.:.lr.rrent oIlhe lo\\' voltage
Dote 3
dLrirg the laull
:ie earthrng anangcment of
::,'\posed-conductive pa : :]e .quipnenl oflhe low ::irse installalion"
142.1.2
Appx.l
-:rrrtance of srpplemenraly . .Jnr! conductor
:.:
m'
power frequ."ncy fauJt voltage that appcars in the lorv voltage
nrVArln
ground flash densjry
.. .reic
Uf
443.5
=:r:ring '::rrnt 1lr thc location of : rouer lhe and connccted
r:
414.5.1
.C
1534)
Drctr.e
-:r:dancc \ oltagc r::1r!r. per lIe! e
Erampl€
-:
ABBREVIATIONS USED IN THE STANDARD Example
Abbreviation
Meaning
Example
Abbreviation Meaning
ACS
Assembly for Construction Sites
104.537.2.2
DCL
Device for connecting luminaire
AFDD
Arc fault detection
421.1.7
CIBSE
Chartered Institution
a
of
41r.7 .5
424.1
Building Services
devices
Engineers
Distribution network
560.6.9
operator
note
ELV
Extra-low voltage
PartZ
EMC
Electromagnetic
332.1
DNO
Part 2
BN
Bonding network
BRC
Bonding ring conductor
A444.1.4
RS
British Standard
1
BS EN
British Standard Euro Norm (BSI Published version of EuroPean
110.1.3
EMI
Electromagnetic intederence
A72\.55.2.6
EN
European Notm
Appx
Energy Networks
560.6.9
Association Earth potential
note
RS EN ISO
harmonized standard) A BS EN which has the
l0.l
.3
compatibility
core text of an ISO standard
BSI BSI IEC
Rritish Standards Institution British Standards Institution lnternational
1
EPR
523.3
rise
-
1
1
/.L) )
stress voltage
Electrotechnical Commission. A BSI IEC means the UK has adopted an IEC standard that has not been Put through from adoption in EuroPe
CBN
Comrnon bonding
444.5.2
ESQCR
network
ElectricitY SafetY, Quality and ContinuitY
114.I
Regulations
CBR
Circuit-breaker
CENELEC
EuropeanCommittee
411'4'4
EV
Electric vehicle
Preface
FELV
Functional extra-low
incorporating residual curent protection not suitable for use bY ordinary Persons
Standardization
fluorescent
cfl CLCITS
European
C
ommifiee
lor Electrotechnical Standardization, Technical SPecifi cation
41.1
\11
.7
voltage
for Electrotechnical compact lamp
111
444'6'2
HD
Hamonization
Preface
Document
534
'
PD
Published Document OEC)
414.2
I
\bbreviation Meaning
Example
Abbreviation Meaning
Example
-:l
Part 2
PE
Protective conductor
Fig 3.8
PELV
Protectiveextra-low
410.3.3
circuit protective conductor
High fiequency
Appx
5
concise list Health and Safety
voltage PEN
Protective and neutral conductor (combined)
PME
Protective
Executive Health Technical
710.1 note 5
Memorandum
multiple
Fig 3.9
Fig 3.9
earlhing
High voltage
442.2
PV
Photovoltaic
712.1
Intemational Electrotechnical Commission
133.1 . I
PVC
Polyvinyl chloride
709.521.1.4
International Electrotechnical
706.1
RCBO
Residual current
Table 41.3
circuit-breaker with integral overcurrent plotection
Commission Technical
Speciflcation Institution of Engineering and
RCCB
Appx I
Residual curent
circuit-brcakcr without integral overcurent
Technology
pl otection
Insulation monitoring
411.6.3
RCD
Intemational Protection
Residual current device
(RCCB or RCBO)
device
Residual current
412.2.2.3
monitor 4l L6.3
Code
Intemational Standards
4721.533.1.6
IIns
root mean square
SELV
Separated
133.2.1
Organisation
extra-low
410.3.3
voltage
device
Liquefied petroleum gas
717.528.3.4
SPD
Surge protective
Lightning protection
534.1
TSE
Transfer Switching Equipment
zone
Luminaire supporting coupler
4fi.7
443.1.1
536.4.2.3
.5
Low voltage
Overcurrentprotective
534.2.3.5
device
--5-
43
PART 3
ASSESSMENT OF GENERAL CHARACTERISTICS CONTENTS CHAPTER
30
ASSESSMENT OF GENERAL CHARACTERISTICS
301
ASSESSMENT OF GENERAL CHARACTERISTICS
CHAPTER 3,I
PURPOSES, SUPPLIES AND STRUCTURE
311
MAXIMUM DEMAND AND DIVERSITY
312
CONDUCTOR ARRANGEMENT AND SYSTEM EARTHING
312.1
General
312.2
Types of system earthing
312.4
lT, multiple source, DC and other systems
313
SUPPLIES
31 3.1
General Supplies for safety services and standby systems
::
314
DIVISION OF INSTALLATION
CHAPTER 32
CLASSIFICATION OF EXTERNAL INFLUENCES
CHAPTER 33
COMPATIBILITY
331
COMPATIBILITY OF CHARACTERISTICS
332
ELECTROMAGNETIC COMPATIBILITY
CHAPTER 34
MAINTAINABILITY
341
GENERAL
CHAPTER 35
SAFETY SERVICES
351
GENERAL
352
CLASSIFICATION
CHAPTER 36
CONTINUITY OF SERVICE
361
GENERAL
PART 3
ASSESSMENT OF GENERAL CHARACTERISTICS GHAPTER 30 ASSESSMENT OF GENERAL CHARACTERISTICS
301
An
301.1
assessment shall be made of the following characteristics of the installation in accordance
with
the chapters indicated:
(i)
The puryose(s) for which the installation is intended to be used, its genelal structure and its supplies (Chapter
3l)
(ii) The extemal influences to which it is to be exposed (Chapter (iii) The compatibility ofits equipment (Chapter 33) (iv) Its maintainability (Chapter 34) (v) Recognized safety setvices (Chapter 35) (yi) Assessment for contiruiiy olselvice (Chapter 36).
32)
CHAPTER 31 PURPOSES, SUPPLIES AND STRUCTURE MAXIMUM DEMAND AND DIVERSITY
311
For economic and reliable design of an installation within thermal Iimits and admissible voltage 311.1 part drop. the maximum dcnand shall be dctcnined. In determining the maxintum detnand of an installation or into accouirt taken thereof. diversity may be CONDUCTOR ARRANGEMENT AND SYSTEM EARTHING
312
The following characteristics shall be assessed:
(i) (ii)
Afiangement of current-canJing conductoN under [onnal operating conditions T1.pe
312.1
ofsystem earthing.
General
inro The following a[angements of curent-carying conductors under nonnal opelating conditions are taken account in this Standard.
3'12.1.1
Current-carrying conductors in AC circuits
I
r-:
Fig 3.1
-
Single-phase 2-wire
45
Fig 3.2
Single-phase 3-wire
-
Llt
N
L2. Phase angle 0" * Numbering of conductors optional
Fig 3.3
-
Two-phase 3-wire
11.
L'l*
L1*
N
L2.
N
l-2"
N
L2* Phase angle 1 20"
Phase angle 90'
Phase angle 180'
* Numbering of conductors optional
Fig 3.4
__/1ll\_
I-/ranrl-..r- -r-
-
Three-phase 3-wire
EI.
rr rz ra
Delia connection
Star connection
Fig 3.5
-
Three-phase 4-wire L1
L2
L3 N or PEN
Three-phase, 4-wire with neutml conductor or PEN conductor. By definition, the PEN conductor is not a live conductor bul a corrdrrctot'carrying an operating cutrent. NOTE 1: In the case of a singlc-phase 2-wire arangement which is derived from a three-phase 4-wire anangement, the two conductoN are either two line conductors or a line conductor and a neufual conductor or a line conductor and a PEN conductor.
NOTE 2: In installations with all loads connected betrveen lines, the installation ofthe neutral conductor may not be necessary
Current-carrying conductors in DC circuits
312.1.2
Fig 3.6
- 2'wire
Fig 3.7
-
3-wire L+
L+
M or PEM
L- or PEL
NOTE:
PEL and PEM conductors are not live conductoN although they canJ operating curent. Therefole, the designation 2-wire afangement or 3-wire arrangement applies.
Types of system earthing
312.2
The following t5pes ofsystem eafihirg are taken into account in this Standard. NOTE
1
: Figures 3.8
to l0
show examples of commonly used three-phase systerns. For lT, mtlltiple source, DC and other
systems see Appendix 9.
NOTE 2: For private systems, the source and/or the dist bution system may be considered aspaftofthe installation within the meaning of this standard.
NOTE 3: The code. used hare the folloning meanings:
Relationship of the power system to Earth:
First letter
-
T |
direct connection ofone point to Eadh
= =
all live parts isolated fiom Earth, or one point connected to Earth through
Second letter
-
a
high irnpedance.
Relationship of the exposed-conductive'parts of the installation to Earth:
direct elecl cal connection ofexposed condlrclive-par1s to Earth, indcpcndenlly olthc eafthing ofan,v
point ofthe po\\,er system direct electrical conneclion of the cxposed-conductive-parts to the eafthed point of the power system (in AC systelrs. the eafthed poilit ofthe power system is normally the neulral point or, ifa neutral point is not available, a line conduclor).
Subsequent letter(s) (if any) - Arrangement of neutral and protective conductors:
S
:
prctective functiol provided by a conductor separate ftom the neutral conductor or fiom the eafihed li1te (of in AC systems, eafihed phase) conductor neutral and protective functions combined in a single conductor (PEN conductor).
47
312.2.1
TN systems
312.2.1.1 Single-sourcesystems TN systcms have onc point dircctly earthed at the soulcc, the exposed-conductive pafis of the installation(s) bcing corlnectcd to that point by protective conductorc. Two types ol TN system are considered according to the affangetrenl of neutral and protective conducto$, as follows:
Fig 3.8
-
TN-S system
source of energy L1
L2 L3 N
/
la
r
protective conductor (PE)
consumers'\ installations
\
l--
source earth
I
exposed-conductive-parts Separate neutraJ and protective conductors throughout the systern. The proiective conductor (PE) is the metal ic covering of the cable supplying the installations or a separate conductor.
All exposed conduclive,parts of an insta lation are connected to this protective conductor via the ma n earthing terminal of the installat on.
Fig 3.9
-
TN-C-S (PME) system
source ot energy L1
L2
L3
consumers'
combined protective and neutral conductor
_1_ \ ,/
installations
\
PEN
additional source earth
source earth I
equipment in
I
in
sta llat io n
I
I
exPosed-conductive'Parts Neutral and protective functions combined in a single conductor (PEN) in a part ofthe system'
'lhis type of distribution is known also as protective multiple eadhing (PIvlE). -l'he
supply system PEN conductor
is
ea(hed attwo or more points and an earth electrode may be necessary ator near a consumer's
instalation. All exposed-conductive-parts of an installation are connected to the PEN conductor via the main earthing terminal and the neutral terminal, these term;nals being llnked togethe.
48
312.2.2
TT system
312.2.2.'l
Single-source system
A TT system has only one point directly eafthed at the source, the exposed-conductive-parts of the i^tallatlon(s) being connected to earth electrodes electrically independent eafih).
Fig 3.10
-
olihe earth electrode olthe supply sys,.* 1,lr" rou.""
TT system
source of energy L1
L2 L3 N
. ,/
consumers'
installations
\
-/\ source earth
I
I
I
I
I
I
I
I
I
installation
l
>
I I
I
l installation
All exposed-conductive-parts earth.
exposed-conductive-parts
installation
earth
earth
electrode
electrode
of an installation are connected to an eatth electrode which is electrically independent of the source
Separate neutral and protective conductors throuqhout the svstem.
NOTE:
Additional eaxthing ofthe pE in the installation may be provided.
312.3 312.4 See
Not used lT, multiple source, DC and other systems
Appendix 9.
313
C"'""4.oJ /d$ uremnv ;
SUPPLIES
313.1
General
The following charactedstics of the suppty or suppries, liom lvhatever source, and the normal range of those characteristics where appropriate, shatt be determined by calculation, measurement, enquiry or inspection: The nominal voltage(s) and its characteristics including harmonic distofiion The nature ofthe current and frequency
(i) (ii) (iii) The prospective shot-circuit curent at the origin of the installation (iv) The earth fault loop impedance ofthat part ofthe system extemal to the installation, Ze (v) The suitability lor the requirements of the insta[ation, incruding the maximum demand (vi) The tlpe and rating ofthe overcurent protective device(s) acting at the origin ofthe installation.
These characteristics shall be ascertained for an extemal supply and shall be determined for a private source. These requirements are equally applicable to main supplies and to saiety services and standby supplies.
NOTE:
The above information should be provided by distributors on request (see Appendix 2 sec 2).
49
Supplies for safety services and standby systems
313.2
Wheretheprovisionofsafetysewicesisrequired,folexample,bytheautholitiesconcemedwithfireplecautions is oithe pre-ir"s, and/or where the provision of standby supplies and other conditions tbr emergency "uu.uu,ion sources of supply for safety ,.qrJ"J UV the pe*on ,pe"iqiing ihe installation, the characteristics of the source or have adequate capacity, reliability unalo, u-dby systems shall be separately assessed. Such supplies shall specified' and rating and appropdate changeover time for the operation
,".r,"",
Chapter 35 hereafter and Chapter 56 NOTE 1: For firfiher requiremerts for supplies for safety services, see in these Regulations' NOTE 2: For standby systems, there are no pafiicular requirements
DIVISION OF INSTALLATION
314 314.1
(i)
(ii)
Every installation shall be divided into circuits, as necessary to: avoid danger and minimize inconvenience in the event ofa fault 46 and Section 537) facilitate safe inspection, testing and maintenance (see also Chapter circuit such as a lighting circuit take account ofhazards that may arise from the failure ofa single (PE) currents not possibility ofunwanted tripping ofRCDs due to excessive protective conductol
(iii) (iv) reduce the
due to a fault
(v) mitigate tbe effects of electromagnetic distubances (see also Chapter 44) (vi) prevent the indirect energizing of a circuit intended to be isolated' 3,14.2separatecircuitsshallbeprovidedforpartsoftheinstallationwhichneedtobesepalatelyContlolled, shall be taken of ar" not'atrected by the failure of other circuits, and due account in such a way that tt ose "ircrit, ofthe operation ofany single protective device' the consequences
circuit, shall offinal circuits required, and the number of points supplied by any final 46 and Chapter protection' overcurent 43 for be such as to facilitate complian." *ith th" ,aq'i'"tents ofChapter conductors of capacities current-carrying iection 537 for isolation and switching and Chapter 52 as regards
314.3
The number
Sl4,4WhereaninstallationcompSesmolethanonefinalcircuit,eachflnalcircuitshallbecorurectedtoa separale liom that ofevery
be elect cally i.purut" *uy in u Aistdbution board. The wiring ofeach final circuit shall oti_rer
final circuit, so as to prevent the indirect energizing of
a
final circuit intended to be isolated.
GHAPTER 32
CLASSIFICATION OF EXTERNAL INFLUENCES Refer to Chapter 51 and APPendix 5
CHAPTER 33 COMPATIBILITY COMPATIBILITY OF CHARACTERISTICS
331
An assessment shall be made of any charactedstics of equipment likely to have harmful effects electrical equipment or other sewices or likely to impair the supply, for example, for co-ordination with upon other concemed parties e.g. petrol stations, kiosks and shops within shops. Those characteristics include, for example: 331.1
(i) trarsient ovewoltages (ii) undervoltage (iii) unbalanced loads (iv) rapidly fluctuating loads (v) starling currents (vi) harmonic cun:ents (vii) earth leakage curent (viii) excessive PE conductor current not due to a fault (ix) DC feedback (x) high-frequencyoscillations (xi) necessity for additional connections to Earth (xii) power factor For an extemal source ofenergy the distributor sha1l be consulted regarding any equipment ofthe installation having a charactedstic likely to have significant influence on the supply.
ELECTROMAGNETIG COMPATIBILITY
332
All electrical cquipmcnt forming paft of an clcctlical instailatioll shali meet the appropriate electromagnetic compatibility (EMC) requirements and shall be in accordance with the relevant EMC standard. 332.1
332.2
Consideration shall be given by the designer of the electrical installation to measures reducing the effect ofinduced voltage disturbances and electromagnetic interferences (EMI). Measures arc given in Chapter 44.
CHAPTER 34 MAINTAINABILITY GENERAL
34',1
34',t.1 An assessment shall be made of the frequency and quality of maintenance the installation can reasonably be expected to receive during its intended life. The person or body responsible for the operation and/or maintenance ofthe ilstallation shall be consulted. Those characte stics are to be taken into account in applying the requirements ofParts 4 to 7 so that, having regard to the ftequency and quality ofmaintenance expected:
(i) (ii) (iii)
any periodic inspection and testing, maintenance and repairs likely to be necessary during the intended life can be readily and safely canied out, and the effectiveness ofthe protective measures for safety during the intended life shall not diminish, and the reliability of equipment for proper functioning ofthe installation is appropriate to the intended life.
NOTE:
There may be padicular statuiory requirements relating to maintenance.
CHAPTER 35 SAFETY SERVICES GENERAL
351 NOTE
1
have : The need for safety services and their nature are frequently regulated by statutory aulhoities whose requirements to be obseNed.
installations for fire NOTE 2: Examples of safety services are: emergency escape lighting, fiIe detection and fiIe alalm systems, pumps, frrefighters
The following electrical sources for safety services are recognized:
351.1
(i) (ii) (iii) (iv)
lifls, smoke and heat exlraction equipment.
Storage battedes
Primary cells Generator sets independent of the normal supply (see Regulation A separate feeder ofthe supply netwolk that is effectively independent ofthe nomal feeder 560.6.5).
352
CLASSIFICATION
Refer to Regulation 560.4.
CHAPTER 36
CONTINUIry OF SERVICE 361
GENERAL
An assessment shall be made for each circuit of any need for continuity of service considered shall necessary during thc intended life ofthe installation, e.g. life-support systems The following characteristics 361.1
be considered:
(i) Seleclion ofrhc s)slem eanhing (ii) Selection ofthe protective device (iii) Number of circuits (iv) Multiple power supplies (v) Use ofmonitoring devices.
in order to achieve selectivity
PART 4 PROTECTION FOR SAFETY CONTENTS CHAPTER
41 PROTECTION AGAINST ELECTRIC SHOCK
410 411 412 413 414 415 416 417
INTRODUCTION PROTECTIVE MEASURE: AUTOMATIC DISCONNECTION OF SUPPLY PROTECTIVE MEASURE: DOUBLE OR REINFORCED INSULATION PROTECTIVE MEASURE: ELECTRICAL SEPARATION
OR PELV PRoTECTIVE MEASURE: EXTRA-LOW VOLTAGE PRoVIDED BY SELV ADDITIONAL PROTECTION PROVISIONS FOR BASIC PROTECTION OBSTACLES AND PLACING OUT OF REACH
4IaPRoTEGTIVEMEASURESFoRAPPLICATIoNoNLYWHERETHEINSTALLATIoN OR INSTRUCTED IS CONTROLLED OC UIOEN THE SUPERVISION OF SKILLED PERSONS
4lgPRovlSIoNSWHEREAuToMATlcDlScoNNEcTloNAccoRDlNGToREGULATIoN 4'I'1.3.2 IS NOT FEASIBLE
CHAPTER
422
PROTEGTION AGAINST FIRE CAUSED BY ELECTRICAL EQUIPMENT PRECAUTIONS WHERE PARTICULAR RISKS OF FIRE EXIST
423
PROTECTION AGAINST BURNS
424
PROTECTION AGAINST OVERHEATING
42'.1
I
42 PROTECTION AGAINST THERMAL EFFECTS
CHAPTER
43 PROTECTION AGAINST OVERCURRENT
430
INTRODUCTION
431
AND THE PROTECTION AGCORDING TO THE NATURE OF THE CIRCUITS DISTRIBUTION SYSTEM
432
NATURE OF PROTECTIVE DEVICES
433
PROTECTION AGAINST OVERLOAD CURRENT
434
PROTECTION AGAINST FAULT CURRENT
435 436
PROTECTION CO-ORDINATION OF OVERLOAD CURRENT AND FAULT CURRENT THE SUPPLY LIMITATION OF OVERCURRENT BY THE CHARACTERISTICS OF
AND CHAPTER 44 PROTECTION AGAINST VOLTAGE DISTURBANCES ELECTROMAGNETIC DISTURBANCES 440
INTRODUCTION
441
NOT USED
442 443
TEMPORARY PROTECTION OF LOW VOLTAGE INSTALLATIONS AGAINST FAULTS." EARTH TO DUE OVERVOLTAGES ATMOSPHERIC ORIGIN OR PROTECTION AGAINST TRANSIENT OVERVOLTAGES OF DUE TO SWITCHING
444
MEASURES AGAINST ELECTROMAGNETIC DISTURBANCES'
445
PROTECTION AGAINST UNDERVOLTAGE
CHAPTER 46 ISOLATION AND SWITCHING
460
scoPE
46't 462 463 464 465
GENERAL ISOLATION
FUNCTIONAL swlTCHlNG (CONTROL) MAINTENANCE SWITCHING OFF FOR MECHANICAL EMERGENCY SWITCHING OFF
CHAPTER 41 PROTECTION AGAINST ELECTRIC SHOCK CONTENTS 410
INTRODUCTION
410.',|
Scope
410.2 410.3
Nof used General requirements
411
PROTECTIVE MEASURE: AUTOMATIC DISCONNECTION OF SUPPLY
411 .1
General
411 .2
411.3
Requirements for basic protection Requirements for fault protection
411.4
TN system
411.5
TT system
411.6
lT system
411.7 411.8
Functional extra-low voltage (FELV) Reduced low voltage systems
412
PROTECTIVE MEASURE: DOUBLE OR REINFORCED INSULATION
412.1
General
4',t2.2
Requirements for basic protection and fault protection
413
PROTECTIVE MEASURE: ELECTRICAL SEPARATION
413.1
General
413.2 413.3
Requirements for basic protection Requirements for fault protection
414
PROTECTIVE MEASURE: EXTRA-LOW VOLTAGE PROVIDED BY SELV OR PELV
414.1
General
414.2
Requirements for basic protection and fault protection Sources for SELV and PELV Requiremenls for SELV and PELV circuits
414.3 414.4
415.1
ADDITIONAL PROTECTION Additional protection: RCDs
415.2
Additional protection: supplementary protective equipotential bonding
415
416.1
PROVISIONS FOR BASIC PROTECTION Basic insulation of live Parts
416.2
Barriers or enclosures
417
OBSTACLES AND PLACING OUT OF REACH
4'16
417 .1 4'17
.2
417 .3
4',t8
418.1
418.2 418.3 4',t9
Application Obstacles Placing out of reach PROTECTIVE MEASURES FOR APPLICATION ONLY WHERE THE INSTALLATION is Cournor-leo oR uNDER THE suPERVlsloN oF SKILLED oR INSTRUcTED PERSONS Non-conducting location Protection by earth-free local equipotential bonding Electrical separation for the supply to more than one item of current-using equipment PROVISIONS WHERE AUTOMATIC DISCONNECTION ACCORDING TO REGULATION 41'1.3.2 IS NOT FEASIBLE
55
CHAPTER 41 PROTEGTION AGAINST ELECTRIC SHOCK INTRODUCTION
410
This chapter deals with protection against electric shock as applied to electrical installations.
It is based
on
livestock. BS EN 6l 140 is BS EN 6 i140, which is a basic safety standard that applies to the protection ofpersons and and equipment installations to electrical give ftmdamental principles and requirements that are common intended to or are necessary for their co-ordination.
is that hazaldous-live-pafis The fundamental rule ofprotection against electdc shock, accolding to BS EN 61140, under normal conditions both not be hazardous-live, shall not be accessible and accessible conductive parts shall and under single fault conditions.
plotective pfolisions According to 4.2 of BS EN 6l140, protection under normal conditions is provided by basic provisions protective provided fault by is and protection under single fault conditions provision, which provides Altemativety, protection against electlic shock is provided by an enhanced protective protection under normal conditions and under single fault conditions
410.1
Scope
including basic protection and Chapter 41 specifies essential requirements regarding plotection against electric shock, requirements fauliprotection ofpe$ons ard livestock. It deals also with the application and co-ordination ofthese in relation to extemal influences. Requirements are given for the application of additional protection in certain cases'
410.2
Not used
410.3
General requirements
410.3.1
-
1n
this Standard the following specification of voltages is intended unless stated otherwise:
I
AC voltages are rms
I
DC voltages are ripPle-free.
I
component Ripple-free is conventionally defined as an rms ripple voltage ofnot mole than 10 % ofthe DC
410,3.2 Aprotective measure shall consist of: (i) an appropriate combination of a provision for basic protection and an independent provision
I
for fault
protection, or
(ii)
plotection. an enhanced protective provision which provides both basic prctection and fault
Additional protection is specified
as part
ofa protective measule under certain conditions of extemal influence and
in cerlain special locations (see the coresponding sections of Part 7)' permitted (see Regulations 410 3 NOTE 1: For special applications, protective measures which do not follow this concept are
5
and 410.3.6).
NOTE 2: An example ofan enhanced protective measure is rcinforced insulation'
410.3.3
ofthe In each part ofan installation one or more plotective measures shall be applied, taking account
conditions of extemal influence. The following protective measures generally are permitted: (i) automatic disconnection of supply (Section 411)
(ii) double or reinforced insulation (Section 412) (iii) electrical separation for the supply to one item of curert-using (iv) extra-low voltage (SELV and PELV) (Section 414)'
I
I
equipment (Section 413)
and erection of equipment' The protective measures applied in the instaltation shall be considered in the selection
For particular installalions see Regulations 410.3.4 to 410.3 9'
NOTE:
56
ofsupply In electical installations the most commonly used protective measue is automatic disconnection
I
I
410.3.4 For special installations or locations, the pafiicular protective measures specified in the corresponding section ofPafi 7 shall be applied. 410.3.5
The protective measures specified in Section 417, i. e. the use of obstacles and placing out of reach, shall only be used in installations restdcted to:
(i) skilled persons, or (ii) instructed persons under the supervision of skilled persons. 41 0.3.6 The protective measures specified in Section 4l 8. i.e. (i) non-conductinglocation (ii) earth-free local equipotential bonding (iii) elect cal separation for the supply of more than one item ol current-using equipment shall be applied only where the installation is under the supervision of skilled or instructed persons so that unauthorized changes cannot be made.
41,0.3.7 Il certain conditions of a protective measure camot be met, supplementary provisions shall be applied so that the protective provisions together achieve the same degree ofsafery NOTE:
An example of the application ofthis regulation is given in Reguiation 411.7 (FELV).
410.3.8
Different protective measures applied to the same installation or par1 of an installation or within equipment shall have no influence on each other such that failure ofo[e protective measure could impair the other protective rneasure or measures.
410.3.9 The provision for fault protection may be omitted for the following equipment: (i) metal suppofis of overhead line insulators which are attached to the building and are placed out of arm,s
I
reach
(ii) (iii)
steel reinlorced concrete poles of overhead lines in which the steel reinforcement is not accessible
I
exposed-conductiYe-parts which, owing to their reduced dimensions (approximate maximum of 50 mm x 50 mm) or their disposition camot be gripped or come into significant contact with a part of the human body and provided that corulection with a protective conductor could only be made with diffrculty or would
I
be unreliable
NOTE:
(iv) (v)
This exemption applies, for example, to bolts, rivets, nameplates, cable clips, screws and other fixings.
metal enclosures protecting equipment in accordance with Section 412 unearthed street fumiture supplied from an overhead line and inaccessible in normal use.
411 411.1
PROTECTIVE MEASURE: AUTOMATTC DTSCONNECTTON OF SUppLy
General
Automatic discoluection ofsupply is a protective measure in which: (i) basic protection is provided by basic insulatiou ol live parts or by bardem or enclosures, in accordance with Section 416, and
(ii)
fault protection is provided by protective earthing, protective equipotential bonding and automatic discon nection in case ofa fault, in accordance with Regulations 411.3 to 411.6.
Where this protective measure is applied, Class II equipment may also be used.
Where specified, additional protection is provided by an RCD with mted residual operating current not exceeding 30 mA, in accordance with Regulation 415.1.
NOTE:
411.2
I
I
Residual Current Monitors (RCMs) are not protective devices but they may be used to monitor residual currents in an electrical installation. RCMs produce an audible or audible and visual signal when a preselected value ofresidual current is reached.
Requirements for basic protection
Al1 electrical equipment shall corrlply with one ofthe provisions lor basic protection described in Section 416 o1 where appropriate, Section 417.
/6ictRtDl( /o+ g\ /o+ fi r-remnv 3
I I
411.3
Requirements lor fault protection
4',t1.3.1
Protective earthing and protective equipotential bonding
41'1.3.'1.1 Protective earthing Exposed-conductive-pafis shall be connected to a protective conductor under the speciflc conditions for each type ofsystem eafihing as specified in Regulations 411.4 to 411.6. Simultaneously accessible exposed-conductive-parts shall be colnected to the sarne earthing system individually,
in groups or collectively. Conductors for protective earthing shall comply with Chapter 54.
A circuit protective conductor shall be run to and teminated at each poir]t in wiring and at each accessory except lampholdel having no exposed-corductive-parts and suspended from such a point.
a
411.3.1.2 Protective equipotential bonding each installation main protective bonding conductors complying with Chapter 54 shall connect to the rnain earlhing terminal extraneous-conductive-parts including the following:
In
(i) (ii) (iii) (iv) (v)
Water installation pipes Gas installation pipes
Other installation pipework and ducting Central heating and air conditioning systems Exposed metallic structuml parts ofthe building.
Metallic pipes entering the building having an insulating section at thefu point of entry need not be connected to the protective equipotential bonding. Connection of a lightning protection system to the protective equipotential bonding shall be made in accordance with BS EN 62305. Where an installation ser-ves more than one building the above requjrement shall be applied to each building.
with the requireurents ofthese Regulations it is also necessary to apply equipotential bondingto anymetallic sheath of a telecommunication cable. However, the consent ofthe owner or operator ofthe cable shall be obtained. To comply
4'11.3.2
Automatic disconnection in case of a fault
41'1.3.2.'l
Except as provided by Regulation 411.3.2.5, a protective device shall automatically interupt the supply to the line conductor of a circuit or equipment in the event of a fault of negligible impedance between the line conductor and an exposed-conductive-par1 or a protective conductor in the circuit or equipment within the disconnection time required by Regulation 411.3.2.2, 411.3.2.3 or 411.3.2.4.
The protective device shall be suitable for isolation ofat least the line conductor.
NOTE:
For IT systems, automatic disconnection is not necessarily required on the occurence ofa 41 I .6.1). For the requil ements for disconnectiol in the event of a second fault, occudng on see Regulalion 411.6.5.
411.3.2.2
58
st fault (see Regulatio[
a
different live conductor',
Maximum disconnection times stated in Table 41.1 shall be applied to final circuits with a rated
current not exceeding:
(i) (ii)
l
63 A with one or more sockeGoutlets, and 32 A supptying only fixed connected curent-using equipment.
TABLE 41,1 _ Maximum disconnection times
50V
l20V
400V
AC TN
0.8
TT
0.3
DC NOTE 1 NOTE I
(s)
(s)
(s)
(s)
Svstem
AC
DC
AC
DC
AC
DC
0.4
1
0.2
0.4
0.1
0.1
0.2
0.04
0.1
0.07
0.4
0.2
Where in TT systems the disconnection is achieved by an overcunent protective device and the protective equipotential bonding is comected with all extmneous-conductive-par1s within the installation in accordance with Regulation 411.3.1 2, the maximum discomection times applicable to TN systems may be used. U0 nominal AC nns or ripple-fiee DC line voltage to Earth
Where compliance with this regulation is provided by an RCD, the disconnection limes in accordance with Table 41.1 relate to prospective residual fault curents significantly higher than the rated residual operating cunent ofthe RCD.
Disconnection is not required for protection against electric shock but may be required for other reasons, such as protection against thermal effects.
NOTE 2: Where disconnection is provided by an RCD,
\ore 4 to Regulation 4l
411,3.2.3
see
Note 2 to Regulation '111.4.4, Note
1
to Regulation 411 5.3 and
1.6.5.
In a TN system, a disconnection time not exceeding 5 s is permitted for a distribution circuit and for
a circuit not covered by Regulation 41 1.3.2.2.
In a TT system, a disconnection time not exceeding 1 s is permitted for a distribution circuit and for circuit not covercd by Regulation 411.3.2.2.
4'l'1.3.2.4 a
411.3.2.5 Where it is not feasible for an overcurrent protective deyice to interrupt the supply in accordance with Regulation 411.3.2 or the use of an RCD for this purpose is not appropriate, see Seclion 419. However, disconnection rlay be required for rcasons other than protection against electric shock. Additional requirements for socket-outlets and for the supply of mobile equipment for use outdoors
411.3.3
In AC systems, additional protection by means of an RCD with a rated residual operating current not exceeding 30 mA shall be provided for:
(i) (ii)
socket-outlets with a mted curent not exceeding 32A, and
mobile equipment with a rated current not exceeding 32A for use outdoors.
An exception to (i) is permitted where, other than for an installation in a dwelling, a documented risk assessment determines that RCD protection is not necessary. The requirements of Regulation 4t1.3.3 do not apply to FELV systems according to Regulation 411.7 or reduced lorv voltage systems according to Regulation 41 1.8. NOTE
1
: See also Regulations
NOTE 2:
See
3
14.1(iv) and 531.3.2 conceming the avoidance of unwanted tripping.
Appendix 2, item 11 in respect
ofisk
assessment.
NOTE 3: A lighring distribution unit complying with BS 5733, luminaire tnck system, installation coupler, LSC or DCL is not regarded as a socket-outlet lor the puryoses ofthis regulation.
411,3,4
Additional requirements for circuits with luminaires
Within domestic (household) premises, additional protection by an RCD with a rated residual operating cunent not exceeding 30 mA shall be provided for AC final circuits supplying luminaires 411.4
TN system
411.4.1 In a TN system, the integrity ofthe eathing ofthe installation depends on the reliable and effective connection of the PEN or PE conducto$ to Earth. Where the earthing is provided from a public or other supply sr stem. compliance with the necessary conditions extemal to the installation is the responsibility ofthe distributor.
411-4.2
The neutral poi[t or the fridpoint ofthe power supply system shall be earthed. midpoint is not available or not accessible, a line conductor shall be earthed.
lfa
I
I
neutral point or
59
Exposed-conductive-parts of the installation shall be connected by a protective conductor to the main earthing tenninal ofthe installation, which shall be connected to the earthed point ofthe power supply syslem.
NOTE:
I
The PE and PEN conductors may additionally be connected to Eafih, such as at the point of entry into the
building.
I
411.4.3 In a fixed installation, a single conductor may serve both as a protectiye conductor and as a neutral conductor (PEN conductor) provided that the requirements of Regulation 543.4 are satisfled. No switching or isolating device shall be inseted in the PEN conductor. NOTE:
I
Regulation 8(4) of the Electricity Safety, Quality and Continuity Regulations prohibits the use ofPEN conductors in
I
I
consumers' installations.
411.4.4
The characteristics of the protective devices (see Regulation 411.4.5) and the circuit impedances
shall fulfiI the following requirement:
ZsxlaSUoxCnin where: is the impedance in ohms (O) ofthe fault loop comprising:
Zs
-
the souce the line conductor up to the point of the fault, and the protective conductor between the point of the fault and the source
is the current in amperes (A) causing the automatic operation olthe disconnecting device within the time specified in Regulation 411.3.2.2, or Regulation 411.3.2.3. When an RCD is used this current is the residual operating current providing discomection in the time specifled in Regulation 411.3.2.2, or Regulation 41 1.3.2.3
la
uo
nominal AC rms or ripple-free DC line voltage to Earth
Cmin
is the minimum voltage factor to take account of voltage variations depending on time and place, changing of transformer taps and other considerations-
NOTE:
For a 1ow voltage supply given in accordance with the Electricity Safery, Quality and Continuity Regulations , Cmin is given the value 0.95.
NOTE
1
: Where compliance with this regulation is provided by an RCD, the disconnection times in accordance with Table 41.1 relate to prospective residual fault currents significantly higher than the rated residual operating curent ofthe RCD.
NOTE 2: In TN systems the residual fault currents are signiflcantly higher than 5 IAn. Therefore, the disconnecting times in accordance with Table 41.1 are fulfilled where an RCD according to BS EN 61008, BS EN 61009 or BS EN 62423 is used. A CBR according 1(r BS EN 60947-2 can be used, provided the time delay is adjusted to afford compliance with Table 41.1.
4'11.4.5 The following rypes ofprotective i ) Ar or ercurrent prolecli\ e de\ ice (i0 An RCD.
device may be used for fault protection:
r
Where an RCD is used for fault protection the circuit shall also incorporate an overcurent protective device in accordance with Chapter 43.
An RCD shall not be used in
a
TN-C system.
Where an RCD is used in a TN-C-S system, a PEN conductor shal1 not be used on the load side. The connection the protective conductor to the PEN conductor shall be made on the source side ofthe RCD.
NOTE:
of
Where selectivity between RCDS is necessary see Regulation 536.4.1.6.
411.4.201 Where a fuse is used to satisfy the requirements ol Regulation 41 1.3.2.2, maximum values of earth fault loop impedance (Zs) conesponding to a disconnection time of 0.,1 s are stated in Table 41.2 for a nominal voltage (Uo) of 230 Y For types and mted curents of general purpose (gG) and motor circuit application (gM) fuses other than those mentioned in Table 41.2, reference should be made to the appropriate British or Harmonized Standard to determine the value ofla for compliance with Regulation 411.4.4.
_60
I
TABLE 41.2
-
for fuses, for 0.4 s disconnection time with Uoof 230 V (see Regulation 4'11.4.201)
Maximum earth fault loop impedance
(Zs)
(a) General purpose (gG) and motor circuit application (gM) fuses to BS 88-2
-
fuse systems E (bolted) and G
(clip-in) Rating
l6
20
25
2.43
1.68
1.29
10
40
50
63
(amperes) 33.1
Z. (ohms)
15.6
7.80
0.99
0.75 0.57
0.44
(b) Fuses to BS 88-3 fuse system C
Rating
16
20
2.30
1.93
45
32
I
(amperes)
Z, (ohms)
9.93
0.91 0.57
0.36
(c) Fuses to BS 3036
Rating
15
45
20
60
9.10
Z" (ohms)
l:
Rating
13
I
(amperes)
(amperes)
NOTE
I
(d) Fuses to BS 1362
2.43
0.56
1.68
0.40
Z.
(ohms) 15.6
2.30
I
The circuit loop impedances have been determined using a value for factor Cmin of0.95.
NOTE 2; The circuit loop impedances given in the table should not be exceeded when: (i) the line conductors are at the appropriate maximum pemitted operating temperature, as given in Table 52. 1, and (ii) the circuit protective conductom are at the approp ate assumed initial temperature, as given jn Tables 54.2 to 54 5.
lf
the conductors arc at a different temperatue when tested, the reading should be adjusted accordingly.
See
Appendix 3.
NOTE 3: Where the line conductor insulation is ofa qpe for which Table 52.1 gives a maximum permitted openting temperature exceeding 70 "C, such as thermosetting, but the conductor has been sized in accordalce with Regulation 512.1.5: (i) the maximum permitted operating temperatre for the purpose ofNote 2(i) is 70 "C, and (ii) the assumed initial temperature for the purpose ofNote 2(i) is that given in Tables 54.2 to 54.4 coresponding to an insulation material of 70
'C thermoplastic.
411.4.202
Where a circuit-breaker is used to satisry the requirements of Regulation 411.3.2.2 or Regulation 411.3.2.3, the maximum value of earth lault loop impedance (2,) shall be determined by the fonnula in Regulation 411.4.4. Altematively, for a nominal voltage (U6) of 230 V and a disconnection time of 0.4 s in accordance with Regulation 411.3.2.2 or 5 s in accordance with Regulation 41 1.3.2.3, the values specified in Table 41.3 for the types and ratings ofovercunent devices listed may be used instead ofcalculation.
I
I
[g6"'"'ri ureenev
,fl,
L^
61
TABLE 41.3
-
Maximumearthfaultloopimpedance(2")forcircuit.ureakerswithUoof230Yforoperation giving compliance *iiit ttt" O'l disconne-ction time of negutati6n
" time of Regulation disconnection " 4'l1'4'2041 Regulation (for RCBOs see also
+1-t.1.2'i;;;
5
40 so 63 80
ffizz
Rating
'
r
6
0.55
0.87
50898
1.37
2.19
0.9sl(5In)
1.09
Z.
0.55
1.09
0.4 sec
(ohms)
1oo
17
x
o.gsl(roIn)
12s 230
0.44
0.68
1.82
0
0.27
40 so 63 80
ffi
Z, (ohms)
0.44
0.68
230
0.22
0.35
0.55
0.87
D circuit-breakers to fS nN OOscs
Rating
x
BS EN 61009-1 the overcu.rent characteristics of RCBos to
(amperes)
Z. (ohms)
In
al 10 16 20 25 32 40 50 63 80 100 125
c circuit_breakers to BS EN Rating
r25
230 1.37
2.19
4.37
4.57
1oo
1.7 5
2.73
7.28
Z- (ohms)
4'11'3'2'3
0.22
0.34
0.14
o
09
x
o.ssl(zor") 230
x
0.22 0.3s 0.5 5 0.87 -''"= ,.rn 1.37 017 o.sslitoIn; 0.27 0.44 0.68 1.09
3.64
using NOTE 1: The cilcr.lit loop irnpedances have been detennined
a value
for factor Cmin of 0 95'
table should not be exceeded when: NOTE 2: The circuit loop impedances gilen in the operating temperature' as given in Table 52 1 and (i) the line conductors are at ti" approptiate maximum pemitted as giver in Tables 54.2 to 54 5' u,,he appropriate assurned initial temperature, (ii) the circnit protecti". "oro,,o,oir'u." should be adjusted accordingly' at a different tempelature when tested, the reading are lf rhe conductoE See
APPendix 3.
temperature rable 52. i gives a maxirnurn pelrnitted operating the line conductor insularion is ofa type for which 512.1 5: Regulation with ,n"..o."r,i,1g, tri,t,e collductor has been sized in accoldance exceeding 70 "c, such and for the purpose.ofNote 2(i) is 70 'C' the maxinum perm'tted opetatin'g temperature to ofNote 21i1 is that given in Tables 54 2 to 54 4 coresponding purpose (ii) the assumed initi'
NorE 3: where
^
(i)
i- *"
an insulation
"t"p"'""t"" matelial of 70 'C themoplastic'
I
4ll.4.2osWhereafuseisusedforadistributioncircuitorafinalcircuitinaccordancewithRegulation4ll.3.2.3, time ol5 s are stated in Table
(Zs) coresponding to a disconnection maxin,um values ofeath fault loop impedance (gG) and motor circuit und iated currents of general purpose typ", io. 41.4 for a nominal voltage (uo) or z}i to the appropriate British u.rade be in fuUtt a t 4' reference silould application (gM) fur., ott t1'u,, tnJ''t ,ot"io'"d 4' 4 41 1 ", Ia for compliance with Regulation or Hannonized Standa.d to det","t".te the value of
v
I
-
TABLE 41.4 Maximum earth fault loop impedance (2") for fuses, for 5 s disconnection time with U0of 230 V (see Regulation 411.4.203J(a) General purpose (gG) and motor circuit application (gM) fuses to BS 88-2 and G (clip in)
Rating
-
fuse systems E (bolted)
4
6
10
16
20
25
32
2t
12
6.8
4.0
2.8
2.2
t.7
50
63
80
100
125
160
200
0.99
0.78
0.27
0.r8
(amperes) 44
Z. (ohms) continued Rating (amperes)
Z. (ohms)
0.42
(b) Fuses to BS 88-3 fuse
Rating
20
63
80
100
Z, (ohms)
3.2
0.68
0.5r
0.38
(c) Fuses to BS 3036
Rating
15
20
30
45
60
r00
s.08
3.64
2.5r
1.51
t.07
0.51
(amperes)
Z. (ohms)
16.8
(d) Fuses to BS 1362
Rating
13
(amperes) 22.0
Z, (ohms)
3.64
NOTE 1: The circuit loop impedances have been determined using
a
value for factor Cmin of0.95.
NOTE 2: The circuit loop impedances given in the table should not be exceeded when: (i) the line conductors are at the appropriate maximum pemitted operatiog temperature, as given in Table 52.1, and (ii) the circuit protective conductors are at ihe appropriate assumed initial temperature. as given in Tables 54.2 to 54.4.
If
the conductors are at a differert temperatue when tested, the reading should be adjusted accordingly.
See
Appendix 3.
NOTE 3: Where the line conductor insulation is of a type for which Table 52.1 gives a maximum pe1.I tted operating temperature exceeding 70 oC, such as thennosetting, but the conductor has been sized in accordance with Regulation 512.1.5: (i) the maximum pennitted operating temperature for the pulpose ofNote 2(i) is 70 "C, and (ii) the assumed initial temperatule for the purpose ofNote 2(i) is that given in Tables 54.2 to 54.5. coresponding to an insulation material of 70 'C themoplastic.
NOTE 4: Data for fuses ofrating exceeding 200 A should be obtained from the manufacturer'
Where an RCD is used to satisfy the requirements of Regulation 411.3 .2.2, 411.3.2.3 or 411.3.2.4 the maximum values of eanh fault loop impedance in Table 41.5 may be applied for non-delayed RCDs to BS EN 61008-1 and BS EN 61009-1 for a nolrinal voltage Uo of 230 V In such cases, an overcurrent protective device shall provide protection against overload current and fault cunent in accordance with Chapter 43.
41'1.4.204
411.5
TT system
411.5.'l
Every exposed-conductive-pafi which is to be protected by a single protective device shall be connected, via the main earthing teminal, to a common earth electrode. However, if two or more protective devices are in series, the exposed-conductive-parts may be connected to separate earth electrodes con-esponding to each protective device. The neutral point or the midpoint ofthe power supply system shall be eathed. available or not accessible. a line conductor shall be earlhed.
Ifa
neutral point or midpoint is not
I
I L
63
4ll.S.2oneormoreofthefollowingtypesofprotectivedeviceshallbeused,theformerbeingpreferred:
(i) An RCD (ii) An overcurrent proteciive device' NoTEI:AnappropriateovelcurrentplotectivedevjcemaybeusedfolfaultprotectionprovidedaSuitablylowvalueofZ.is assured' Permanently and reliably
in should also incorporate an overcurrent protective device NOTE 2: Where an RCD is used lbr fault prctection the circuit accordance with Chapter 43' be fu1filled:
411,5.3 Where an RCD is used for fault protection' the following conditions shall and (i) The disconnection time shall be that required by Regul ation 411 3 2 2 or 411 3 2 4' (ii) Rr x IAn S 50 V where:
RAisthesumoftheresistancesoftheealthelectlodeandtheplotectiveconductolconnectingittothe exposed-conductive-parts (in ohms)
is the mted residual operating curent ofthe RCD'
Ion
The requirements of this regulation are met meets the requirements ofTable 41 5'
if the eadh fault loop
impedance of the cilcuit protected by the RCD
to Regulation 536 4 1'4' NOTE 1: Where selectivity between RCDs is necessary refer also NOTE 2: Where RA is not known, it may be replaced by Zs'
-
TABLE 41.5 (2") for non-delay,e-d and time delayed'S'Type RCDs to Maximum earth fault loop impedance eH oioo'gt for uo of 230 V (see Regulation 411.5.3) BS EN 61008-1
""J-ds
Rated residual Ma-'rimum earth fault operating Ioop impedance Z"
current (mA)
Disconnection shall be within the times stated in Table 41
1
NoTEI:FiguresforzsresultfromtheapplicationofRegulation4ll.5.3(i)and(ii). NOTE
2:
* The resistance ofthe installation earth electrode should be as low may not be stable Refer to Regulation 542 2 4'
as practicable.
A value exceeding 200 ohms
4'll.5.4Whereanovercurrentprotectivedeviceisusedthefollowingconditionshallbefulfilled:
ZsxIalUoxCmin where:
Zs
is the impedance in ohms (Q) of the earth fault loop comprising:
-
the source the line conductor up to the point of the fault the protective conductor from the exposed-conductive-parts the earthing conductor
-
the eafih elecftode ofthe installation and
I
the eadh electrode ofthe source
I
operation olthe disconnecting device within the is the current in amperes (A) causing the automatic time specified in Regulation 411 .3.2.2 or 411 3 2'4
Ia
nominal AC ms or ripple-free DC line voltage to Eafth
Uo Cmnr
depending on time and place' is ihe minimum voitage factor to take account ofvoltage variations changing oftransformer taps and other considerations'
NOTEIForalowvoltagesupplygiveninaccordancewiththeElectricitySafety'QualityandContinuiiyRegulationsas amended. C*:, is given the value 0 95'
I
I I
lT system
4',t't.6
41',t.6.1 In an [T system, live parts shall be insulated from Earlh or comected to Earth through a sullciently high impedance. This connection may be made either at the neutral point or midpoint ofthe system or at an artificial neutal point. The latter may be connected directly to Eafih if the resulting impedance to Earth is sufficiently high at the system frequency. Where no neutml point or midpoint exists, a line conductor may be connected to Eafih through a high impedance. Where the above conditions apply, the fault current is then low in the event ofa single fault to an exposed-conductivepafi or to Earth,so that automatic disconnection in accordance with Regulation 41 1.3.2 is not imperative provided that the condition in Regulation 41 1.6.2 is fulfllled. Precautions shall be taken, however, to avoid the risk ofharmful effects on a person in contact with simultaneo,rsly accessible exposed-conductive-parts in the event of two faults existing simultaneously.
I I I
I
NOTE 1: It is strongly recommended that [T systems with distributed neutrals should not be employed.
I
NOTE 2: To reduce oveNoltage or to damp voltage oscillation, it may be necessary to provide earthing through impedances or afiificial neufral points, and the characte stics ofthese should be appropriate to the rcquirements ofthe instailation.
41'1.6.2
Exposed-conductive-parts
shall be eafihed individually, in groups, or collectively.
In AC systems the following condition shall be fulfilled to limit the touch voltage to:
RAxId<50v where: is the sum ofthe resistances in ohms ofthe earlh electrode and protective conductor for the exposedconductive-parts.
RA
is the fault cuffent in amperes (A) ofthe first lault ofnegligible impedance between a line corductor and an exposed-conductive-part. The value ofld takes account ofleakage currents and the total eafihing impedance of the electrical installation. No touch voltage limitation is considered iD DC systems as the value ofld can be considered to be negligibly low.
The following monitoring devices and protective devices may be used:
41't .6.3
(i) (ii) (iii) (iv) (v)
insulation monitoring devices (IMDs)
I
residual current monitoring devices (RCMs)
I
insulation fault location systems (IFLS) overcurrent protective devices (OCPD)
residual curent devices (RCDs).
NOTE 1: Where an RCD is used, t pping ofthe RCD in the event ofa first fault cauot be excluded, due to capacitive leakage curents. NOTE 2: In case offaults ill tu,o differcnt Class I cuaent-using devices supplied by different line conductors, the operation ofan RCD is only likely to be achieved if every single item ofcurent-using equipment is protected by an individual RCD. In such a qase, the use ofan overcurent prctective device is more suitable.
411.6.4
Where an IT system is designed not to disconnect in the event ola first fault, the occurence ofthe
first fault shall be indicated by either;
(i)
an insulation monitoring device (IMD), which may be combined with an insulation fault location system
(IFLS), or
(ii)
a
NOTE: I
residual curent monitor (RCM), provided the residual current is suf6ciently high to be detected. RCMs are not able to detect symmetrical insuladon faults.
The device shall initiate an audible and/ol visual signal which shall continue as long as the fault persists. The signal can be initiated via a relay contact output, an electronic switching output or a communication protocol.
I I
A visual and/or an audible alam system shall be aranged at a suitable place, so that it is perceived by responsible
I
persons.
I
Ifthere are both audible and visible signals, it is pemissible for the audible signal to be cancelled.
65
61557-9 may be provided to indicate the location In addition, an insulation fault location system according to B S EN another refercnce point' ofa first fault from a live part to exposei-conductive-pads or Earth or
411'6'sAfteltheoccurenceofafiIstfault,conditionsforautomaticdiscorurectionofsupplyintheeventof a second
fault occurring on a different live conductor shall be as follows:
(i)Whereexposed.conductive-pafisaleintelconnectedbyaplotectiveconductolcollectivelyearthedtothesame
earthingsystem,theconditions,i-ifu"oaTNsyttetapplyandthefollowingconditionsshallbef[lfilled and in DC syslems where the midpoint conductor where the neutral conOr"to, i. not Ai.t iUuted in Ab systems is not distributed:
TlxC
L,=__T_ olwheletheneutlalconductololmidpointconductorrespectivelyisdistributed: Uo t C,o-, ------L;= where:
U Uo Z"
conductors is the nominal AC or DC voltage, in volts, between line and neutml conductor or is the nominal AC or DC voltage, in volts, between line conductor midpoint conductor. as appropriate line conductor and the protective is the impedance in ohms ofthe fault loop comprising the
conductor of the circuit
Zt,
neutral conductor and the protective is the impedance in ohms of the fault loop comprising the conductor of the circuit
I"isthecurentinamperes(A)causingoperationoftheplotectivedevicewithinthetimelequhedin
C.i"
3 Regulation 41 1.3 2.2 for TN systems or Regulation 411 3 2 variations depending on time and place' is the minimum voltage factor to take account ofvoltage changing oftransformer taps and other considerations
the TN system is applicable to IT systems with NOTE 1: The time stated in Table 41.1 of Regulation 411.3.2.2 for
a
distributed
or non-distributed neutral conductor or midpoint conductor' the event of the simultaneous occufence of two faults' the NOTE 2: The factor 2 in both fbrmulae takes into account that in fauits may exist in different circuits'
NoTE3:Forfaultloopimpedance,themostseverecaseshouldbetakenintoaccount.e.g.afauitonthelirleconductolatd]e considered ofcurrent-using equiprnent ofthe circuir source and simultaneously another fault or the neutral conductor
(ii)Wheretheexposed-conductive-pafisaleearthedingroupsorindividually,thefollowingconditionapplies:
Re.xIa!50V where:
RAisthesumoftheresistances,inohms,oftheearthelectrodeandtheprotectiveconductortotheexposedcooductive-Parts
1"
the disconnection device in a time complying is the current in amperes causing automatic disconnection-of a time complying with Regulation with that for TT sys,"^, i, iuui" + r. r of Regulation 411.3.2.2 or in 411.3.2.4.
I
for an RCD' compliance with the disconnection times required NOTE 4: Ifcompliance to the requirements of(ii) is provided by TTsystemsinTable4l,tmayrequi,eresidualctmentssignificantlyhigherthantheratedresidualoperatingclrlTent l^n ofthe RCD applied (typically 5 t^n)'
i
41',t.7
Functional extra-low voltage (FELV)
411.7 .1
General
Where, for flrnctional rcasons, a nominal voltage not exceeding 50 V AC or 120 V DC is used but not all the requiremeflts ofSection 414 relating to SELV or to PELV are fulfilled, and where SELV or PELV is not necessary, the supplementaD, provisions described in Regulation 41 1.7.2 and 411.7.3 shatl be applied to provide basic protecrion and fault protection. This combination ofprovisions is known as FELV
NOTE:
Such conditions may, for example, be encountered where the circuit contains equipment (such as transformers, relays, remote-conftol switches, contactors) insLrfficiently insulated with respect to circuits at higher voltage.
411.7.2
Requirements for basic protection
Basic protection shall be provided by either:
(i) (ii) 411.7
basic insulation according to Regulation 416.1 coresponding to the nominal voltage ofthe primary circuit ofthe source, or barriers or enclosures in accordance with Regulation 416.2.
.3
Requirements for fault protection
The exposed-conductive-pafis ofthe equipment ofthe FELV circuit shall be connected to the protective conductor of the primary circuit ofthe source, provided that the primary circuit is subject to protection by automatic disconnectiou
of supply as described in Regulations 411.3 to 41 I .6.
Sources
411.7 .4
The source of the FELV system shail either be a transfomer with at least simplc scparation bctuccn windings or sha)l comply with Regulalion 414.3.
If al extra-low voltage
systcm is supplied frorn a higher voltage system by equipment which does not provide at least simple sepamtion between that system and the extE-low voltagc system. such as an autofansfonrer. a potentiomet or a scmiconcluctor device, the output circuit is not pan of a FELV syste;n and is deemed to be an extension ofthe input circuit and shall be protectcd by thc protcctive measure applied to the input circuit.
NOTE:
This does not preclude connecting a conductor oftbe FELV circuit to the protective conductor ofthe primarJ crrcuir.
4'l'1.7.5
Plugs, socket-outlets, LSCs, DCLs and cable couplers
Every plug, socket-outlet, luminaire supporting coupler (LSC), device for connecting a luminaire (DCL) and cable couplel in a FELV system shall have a protective conductor contact and shall not be dimensionally compatible with those used for any other system in use i[ the same premises.
4'11.8 411.8.1 411 .8.1
.1
Reduced low voltage systems General Where, for functional reasons, the use ofextmlow voltage is impracticable and there is no requirement
for the use of SELV or PELV, a reduced low voltage system may be used, for which the provisiol'rs described in Regulations 411.8.2 to 5 shall be made to provide basic protection and fault protection. 411 .8.1 .2 The nominal voltage of the reduced low voltage circuits shall not exceed I Iines (three-phase 63.5 V to earthed neutral, single-phase 55 V to earthed midpoino.
4'11.8.2
l0 V AC rms between
Requirements for basic protection
Basic protection shall be provided by either:
(i) (ii)
basic insulation according to Regulation 416.1 corresponding to the maximum nominal voltage of the reduced low voltage system given in Regulation 411 .8.1 .2, or
bariers or enclosures in accordance widr Regulation 416.2.
411.8.3
Requirements for fault protection
o,::":lTlJ.:lo':l,o.iljll:::xj:Ii:1,:'"1:T[:{iJ.:J::'Ji:ll.!:":;:i:'; ',ti b1 of ,rltiration. including socket-outlet"p(
Faurr prorecrion by auromaric or der ice in each line conductor
,'fr"ii
at every Eafih rhe earth fault loop impedance
;
ffi il;;;""d
i" ,t"fr,rr" ,f-re disconnection time does not exceed
5 s'
(Z') shall be determined by the ralue ofeanh lault loop imoedance maximum lhe used is of calculation Where a circuit-breaker to*'ntai'-r"r'it'+r'o ma} be used instead o o o" rormula in Resulation therein tit q';"";'J '"i"g' oio""ott"nt device listed (U0) for the nominal voltages "rra
o"t'"i"iiti'"t#"j*t
Whereafuseisused,themaximumvaluesofearthfaulttoopimpedance(Zs)conespondingtoadisconnectiontime V and 61 5 V nominal volrages (Uo) of 55 of 5 s are stated in Table 41 6 tbr For qpes and
e*.",T.:t::l_1":l;l*;ln.m n'il:i;|,:"Ji:'tl:i;iiiilll':i["X],:,ffi,[i';"1;i:
cnnrnnriate British or Harmontzec
::#5,fi;;;';ffip'iate
'atu'
orrt''
nominal roltage tUo)
v
whelefaultprotectionisprovidedbyanRCD,theploduct.of^theratedresidualoperatingcurrent(Iln)inamperes exceed 50
^.lilr"
not roop impedance in ohnls sha1l
."nfi"ri'
-
TABLE 41.6
Us of 55 V (z:)-lo'- ?'""9:tonnection time and Maximum earth fault loop impedance v
i"jl gi;fp-h"""r "n.i'os's ch*'il1? 411'8'1'2 and 41'l'8'3) iseJ Regutations
F',ffii]6.*rl*tt,"
BS EN 60898 and the
to nrer.u.r"nt char"cteristics of RCBOs BS EN 61009-1
Uo
Horg
;;;
-
(Volts) Zs ohms
Rating
t,
General PurPose (gG) fuses to BS 88-2 fuse systems E and G
3.48
4.02
t.'7
4
2.01
3
0.87
1.01
3.35
1.',74
2.01
2.90
6
0.52
0.60
1.89
1.05
t.21
1.63
10
0.7 5
0.3 3
0,95
I .10
0.65
0.3 8
16
0.60
0.26
0.30
0.'7'7
0.52
0.6'7
20
0.48
0.21
0.52
0.60
0.42
0.24
25
0.16
0.48
0.3 8
0.42
0.33
0.19
32
0.30
0.13
0.15
0.35
0.26
0.31
40
0.24
0.10
0.12
0.2'7
0.21
0.24
50
0.19
0.08
0.10
0.22
0.17
0.19
63
0.13
0.15
0.08
0.13
80
0.07
0.15
0.12
0.05
0.12
0.14
0.10
0.06
100
0.10
0.04
0.0s
0.09
0.08
0.08
125
uffiila
uting
,*-Ir-au-,"*,*t-iln-
,t,"
a
value for factor cmrn of 0 95'
"ir,',rfrp table shouldnor3"::"rt*Jlii; ,, ;;" ;, loop impedances giver rn the (ir the rine conductor: *. .t ,1" :ll_':ll';jjila};#ffi;Ji"iiiu] ,"^p",u*'", u. siven in rables s4.2 to i:,"*1li::11ffi,:T:::il:il:Jili::TH:::"::::*:**X*::^r,:',:H::';ffi'13:i:;'.',1fl:
tii)
ar( the circuit protecli\e conductors
5'16.
li
accodingl)'' reading should be adjusted telnpeLature when tested the dillerent a at arc the condllctors
See
Appcndix
3.
=-I NorE 3: $here
the line conductor insulation is ofa t)?e for which rable exceeding 70 oC, such as thennosetting, but the conductor has
(i) (ii)
gi'es a maximum permitted oper ating temperaftue been'sized in accordance with Regulation 512.1.5: the maximum permitted operaling temperature for rhe purpose ofNote 2(i) is 70 oC, and the assumed initial temperature for the pu,po." orNot" is thar given ir Tables 54.2 to 54.4 conesponding to an insulation rnaterial of70 "C themtoplastic. 5-2.1
uiil
NOTE 4: Data for fuses ofrating exceeding 200 A should be obtained from the ma,,ufacturer.
411.8.4
Sources
411.8.4.1
The source ofsupply to a reduced low voltage circuit shall be one ofthe following: A double-wound isorating transfomer comprying with BS EN 61558-1
(i) (ii)
andBSEN6r558-2-23
A motor-generator set having windings providing isolation equivalent to that provided by the windings of an isolating transformer
(iii)
A source independent olother supplies, e.g. an engine_driven generator
4'11'8'4'2 The neutral (star) point ofthe secondary windings ofthree-phase transformers and generators. or the ^ - secondary midpoint ofthe windings ofsingle-phase transfo..i. unJ-g"n"ru,ors, shall be connected to Eafth.
411,8.5
Requirements for circuits
Every plug, socket-outlet, luminaire supporting coupler (LSC), device for connecting a luminaire (DCL) and cable coupler of a reduced low voltage system shall have a prot"ctiu" coni*tor and shall not be dimensionally compatible with those used for any other system in use in the same premises."ontu"t
412
PROTECTIVE MEASURE: DOUBLE OR RETNFORGED |NSULATtoN
412.1
General
412.'t.1
Double or reinforced insulation is a protective measure in which: basic protection is provided by basic insulation and fault protection is provided by supplementary insulation,
(i)
or
(ii) basic and fault protection is provided by reinforced insulation between live pafts and accessible pats. NorE: This protective measure is intended to prevent the appearance ofa dangerous elect cal equipment through
a
voltage o,, the accessible parts
fault in the basic insulation
The protective measure ofdouble or^reinfo_rced insulation is applicable in given in the coresponding section ofpart 7.
4't2.1.2
al1
of
situations, unless some lifiritations are
where this protective measure is to be used as the sole protective measure (i.e. where a whole
ii:i"lill3i,"T;:fii:l'"fl:l*11:::Tnt
ent"af
or'quffi;;ff;;; ffi;;:;:::"ffi;lTi#:l:
1;::*,1:]::T imgarr the efiectwen",, ortn. p,ot..t*.;;;il:il;;;;;;;;,;;ffi;,il#:;:1JJ:ii:;;:1 .:"T:::i$i'L",'i:T"::::1'"',::,::,"Yo'''pr",,.o.r"t-o;,r";;j,h-;;';",,h#ffi".,,ffi#iJ:HHl"J for con-nectins a ruminaiie iocrt .,."ii"'".";l;;;;#ffi;;'#ff;"r,.:il:? il;ll;*?jlj:::ce equipment lvithout authodzation. 4'12.2 412.2.1
Requirements for basic protection and fault protection Electricalequipment
where the protective measure double or reinforced insulation is used for the complete installation or pafi there ot, electrical equipment shall comply with one olthe followine :
(i)
(ii) (iii)
.^-
Regulation 412.2.1.1. or Regul ations 4 I 2.2.t .2 and 412.2.2, or
Regulations 412.2.t.3 and 412.2.2.
f"*%g\ /9= f urenanv ! 69
I
and marked to the rclevant standards: Electrical equipment shall be ofthe following types' t)lle-tested (Class II equipment) electrical equipment having double or reinforced insulation
412.2.1.1
(i)
(ii)electricalequipmentdeclaredinthelelevantploductStandardasequivalenttoClassll,suchasassemblies
''-' oi"t""tri"ui NOTE:
having total insulation (see BS EN 61439 series)'
"quipment
This equipment is identilied by the symbol
@
rcfer to BS EN 60417: Class
I
I I
ll
equipment
supplementary insulation applied in Electdcal equipment having basic insulation only shall have equivalent to electrical equipment of erecting the'ellctrical insta-llation, providing a degree of safety a;. ;;;t 412 2 2 'l to 412 2'2'3' accordins to Regulation 412.2.1.1 and complying with Regulations
I
4'12.2.1.2
HOfg: ile srirtol @
arrd interior ofthe enclosure shor-rld be lixed in a visible position both on the exterior
4l2,2.l.3Electdcalequlpmenthavinguninsulatedlivepaltsshallhavereinforcedinsulationappliedinthe equipment in'tuffion, froviaing a d"g"e of safety equivalent to elect cal process of erecting the is insulation Such 2 3. 4l|2.2 "f".t,i.ur and ions 412.2.2.2 according ro Regutarion 4 t 2.2. L I ;;;.;;plying wirh"Regut;r insulation' double ."-il;d -lv;"here constructional features prevent the application of and interior of the enclosure' should be iixed in a lisible position botb on the exterior NOTE: the symbol
Q
412.2.2
Enclosures
4l2.2.2.lTheelectricalequipmentbeingreadyforoperation,allcorrductivepafisseparatedfromlivepartsby affording at least the degree ofprotection IPXXB basic insulation only, st.,ult U" contulneJin un-inrrtutlng .n"losure or IP2X. The following requirements apply as specified:
412.2.2.2
(i)theinsulatingenclosureshallnotbetraversedbyconductivepartslikelytotlansmitapotential;and material which (ii) the insulating enclosure shall not contain any screws or other flxing means of insulating installation and maintenance and whose might need to be removed,;; are likety to b" '"''ou"d' during impair the enclosure's insulation' repiacement by metallic screws or other fixing means could
joints or connections (e g for operating handles where the insulating enclosure must be traversed by mechanical protection against shock in case ofa fault is not ofbuilt-in equipment), these shoutdbe ananged in such a way thai impaired.
4l2.2.2.sWherealidordoolintheinsulatingenclosulecanbeopenedwithouttheuseofatoolorkey,all behind an insulating barrier (providing a parts which ur" u"""*ltt" ii,t lid orioor is open shall be " ftom coming unintentionally into contact o.gr." pi"*"i"n not less than lpxxB or Ip2X) preventing persons use of a tool or key' "r parts. This insulating banier shall be removable only by the ri?t ihor"
;;;",*
"onOr.tive
412.2.2.4Conductivepaltsenclosedintheinsulatingenclosureshallnotbeconnectedtoaplotectiveconductol' which necessarily run through the enclosure However, provision -uy U" -uaa tJao*e"ting p'ot""tle "onductors through the enclosure lnside
*lor"
supply circuit also runs bi insulated as though they were live parts' and their the enclosure, terminals shall be narked as protective conductor (PE) terminals' to a protective conductor unless specific No exposed-conductive-parts or intermediate palt shall be connected proui.ion fot tt i, it madi in the specification for the equipment concemed' protected in this way' 412.2.2.5 The enclosure shall not adversely affect the operation ofthe equipment
in order to serve other items
"f "l;;;';rrpri.r, any such conductor. urd tt eit t".minats
412.2.3
shal1
lnstallation
(fixlrle' connection of conducton' The installation of equipment mentioned in Regulation 4122'1 in compliance with the equipment afforded prof,ction etc.) shall be effected ln..r"r., u *ui''u', not to impair the
412.2,3.1
specification. Except where Regulation 412 12applies,acircuitsupplyingofleormoreitemsofClassI1equipment point in wiring and at each accessory' circuit protective conJuctor run to and terminated at each
412.2.3,2 shall have a
NoTE:ThiSrequirementisiutendedtotakeaccountofthereplacementbytheuselofClassllequipme[tbyclassl equip1nent.
I I
I
I
412.2.4
Wiring systems
412.2.4.1
Wiring systems installed in accordance with Chapter 52 are considered to meet the requirements of
Regulation 412.2 if:
(i) (ii)
the rated voltage ofthe cable(s) is not less than the nominal voltage ofthe system and at least 300/500 V, and adequate mechanical protection ofthe basic insulation is provided by one or more
ofthe following:
(a) The non-metallic sheath ofthe cable (b) Non-metallic trunking or ducting complying with the BS EN 50085 series olstandards, or non-metallic conduit complying with the BS EN 61386 series ofstandards. Cable product stardards do not specify impulse withstand capability. Howeveq it is considered that the insulation the cabling system is at least equivalent to the requirement 111 BS EN 61140 for reinforced insulation.
NOTE
NOTE 2: A wiring system shonld not be identif,ed by the symbol
@
or by the symbol
413
PROTECTIVE MEASURE: ELECTRICAL SEPARATION
413.1
General
413.1.1
Electrical separation is
a
P
of
.
protective measure in which:
basic protection is provided by basic insulation of live parts or by bariers or enclosures in accordance with Section 416. and
(1)
(ii) fault protection is provided by sin.rple separation of the separated circuit from other circuits and from Ear1h. 413,1 .2 Except as permitted by Regulation 413. .3, this protective measure shall be limited to the supply of 1
one item ofcufient-using equipment supplied from one unearthed source with simple separation. NOTE: When this protective measure is used, it is particularly impofiant that the basic insulation complies with the relevant product standard.
413,1,3 Where more than one item of curent-using equipment is supplied from an unearthed source with simple separation, the requirements ofRegulation 418.3 shall be met. Requirements for basic protection
413.2
AII electdcal equipment shall be subject to one ofthe basic protective proyisions in Section 416 or to the protecrive measures in Section 412.
Requirements for fault protection
413.3 413.3.1
Protection by electrical separation shall comply with Regulations 413.3.2 to 413.3.6.
4't3.3.2 The separated circuit shall be supplied through a source with at least simple separatior, ard the voltage ofthe separated circuit shall not exceed 500 V
413.3.3
Live parts ofthe separated circuit shall not be connected at any point to another circuit or to Eafth or to a protective conductor. For electrical separation, anangements shall be such that basic insulation is achieved between circuits in compliance rvith Regulatiou 416. 1.
413.3.4 413.3,5
Flexible cables shall be visible throughout any part oftheir length liable to mechanical damage.
For separated circuits the use of separate wiring systems is recommended. If separated circuits and otl]er circuits are in the same wiring system, multi-conductor cables without metallic covering, insulated conductors in insulating conduit, insulating ducting or insulating trunking shall be used, provided that:
I
I I I
(i) the rated voltage is not less than the highest nominal voltage, and (ii) each circuit is protected against overcunent. 413.3.6 The exposed-conductive-pafis ofthe separated circuit shall not be connected either to the protective
I
conductor or exposed-conductive-parts ofother circuits, or to Eaflh.
I
NOTE: lf the exposed-conductive-parts of the separated circuit are liable to come into contact, either i[tentionally or fo uitously, with the exposed-conductive-parts of other circuits, protection against electric shock no longer depends solely on protection by electrical separation but also on the prctective provisrons ro which the larter e\posedconductive-parts arc subject.
71
BY SELV OR PELV PROTECTIVE MEASURE: EXTRA'LOW VOLTAGE PROVIDED
414
4'14.1
General
4l4,l.lPlotectionbyextlalowvoltageisaplotectivemeasurewhichconsistsofeitheloftwodiffelent extralow voltage systems: (i) SELV or
(ii)
PELV
requires: Protection by extra-low voltage provided by SELV or PELV (iii) limitation of voltage in the SELV or PELV system to the upper limit ofvoltage Band
I'
50 V AC or 120
V
DC ((ee BS EN bll40). and
(iv)plotectiveSeparationoftheSELVoIPELVSystemftomallcilcuitsothelthanSELVandPELVcircuits,and pElvsystem and other sELV or PELV systems, and between th; 5ELV or basic insulation
(v)
and Earth' for SELV systems only, basic insulation between the SELV system
TheuseolsELVorPELVaccoldingtosection4l4isconsideredaSaprctectivemeasureinallsituations.
414.1.2
a value lower than 50 v AC or 120 V DC' In certair cases Part 7 limits the value ofthe extra-low voltage to
NOTE:
Requirements for basic protection and fault protection
414.2
provided where: Both basic protection and fault protection are deemed to be (i) the nominal voltage cannot exceed the upper limit ofvoltage Band 1' and (ii) the supply is from one ofthe sources listed in Regulation 414 3' and
(iii)
the conditions of Regulation
4
1
4 4 are
fulfilled'
NoTEI:IfthesystemissuppliedliomahighervoltagesystembyequipmentwhichprovidesatleastSimpleseparationbetween and PELV sources meet the requirements for SELV that system and the extra_low voltge system but which does not see Regulation 411'7' app)icable' be may in Regulation 414.3, the requirements for FELV
NoTE2:DCvoltagesforELVcircuitsgeneratedbyasemiconductorconveltol(seeBSEN60146-2)tequireanintemalAC exceeds the DC voltage The internal AC circuit voltage circuit to supply the reitifier stack This iltemal AC voltage iSnottobeconsideredasahighervoltagecircuitwithinthemeaningofthisregulation,Betweenintemalcircuitsand extemal higher voltage circuits, protective sepamtion is required' I
NoTE3:lnDCsystemswithbatteries,thebatterychalgingandfloatingvoltagesexceedthebatterynominalvoltage,depending provisions in addition to those specified in this regulation. on the type ofbattery. This does not reiuire any protective V AC or 150 V DC as appropriate according to the The charging voltage should not exceed a marimum value of 75 environmental situation as given in Table 1 ofPD 6536 (IEC 61201)'
I
Sources for SELV and PELV
414.3
Tbe following sources may be used for SELV and PELV systems: (i) A safety isolating transfotmer in accordance with BS EN 61558-2-6 or BS EN 61558-2-8 specified (ii) A source ofcurrent providing a degree ofsafety equivalent to.thal.ofthe safety isolating fansformer in (i) (e.g. motor-genemtor with windings providing equivalent isolation) circuit (e g a (iii) An electrochemical source (e.g. a battery) oI another source independent of a higher voltage
diesel-ddven generator)
(iv)
Cefiain electrcnic devices complving with appropdate sta:rdards' Yh"i: at the outgoins termt"il'
;:l:ffii'';;.I*;;iilffi?;i;,-,i,'"'""i'"e" u,,ti" o"goinsterminats
ryl]:t:'-l111:"t"t:.t*:li*
:T:'-:l:::ljTJ::":: are' howe]-I:f':111i"I1""]j;I *lltil.," iiilri"ioJili.i.;'sh..;oto!", :ffi;;"",';il"lit" p"n "r li,rr" .veniof a fautt beiveen a live pafi and^an "]p:ttd-::ld"::i)";1"1: thevoltageattheouputterminalsisimmediatelyleducedtothevaluespecifiedinRegulation4l4.l.lor 1ess.
and monitoring devices' NOTE 1: Examples ofsuch devices include insulatior testing eqripment
NOTE2:Wherehigh".uot,ug","ti"u'tl"outgoingterminals'compliancewiththisregulationmaybeassumedifthewiih the limits specifled in Regulation 4!4 1 1 when rneasured voltage at the outgoing tenninals is within voltmeter having an internal resistance ofat least 3 000 ohrns'
a
Amobilesourcesuppliedatlowvoltage,egasafetyisolatinghaosformeroramotor-generator'shallbeselected double or reinforced insulation (see in accordance with the reiiieients for protection by the use of and erected Section 412).
Requirements for SELV and PELV circuits
414.4 414.4.1
(i) (ii)
SELV and PELV circuits shall have: basic insulation between live pafts and other SELV or PELV circuits, and
protective separation from live parts of circuits rot being SELV or PELV, provided by double or reinforced insulation or by basic insulation and protective screening for the highest voltage present.
I
SELV circuits shall have basic insulation between live pafis and Ear1h.
I
The PELV circuits and./or exposed-conductive-parts ofequipment supplied by the PELV circuits may be earthed. NOTE 1: In particular, protective separation is necessary between the live paits of electrical eqllipment such as relays, contactors and auxiliary switches, and any part ofa higher voltage circuit or a FELV circuit. NOTE 2; The earthing ofPELV circuits may be achieved by
a
connection to Earth or to an ealthed protective conductor within
the source itself.
414.4.2 Protective separation ofwiring systems ofSELV or PELV circuits from the live parts olother circuits, which have at least basic insulation, shall be achieved by one ofthe following arrangements; (i) SELV and PELV circuit conductors enclosed in a non-metallic sheath or insulating enclosure in additioll to basic insulation (ii)
SELV and PELV circuit conductors separated from conductors of circuits at voltages higher than Band I by an earthed metallic sheath or earthed metallic screen
(iii)
Circuit conductors at voltages higher than Band I may be contained in a multi-conductor cable or other grouping ofconducto$ ifthe SELV and PELV conducton are insulated for the highest voltage present
(iv) The wiring systems ofother circuits are in compliance with Regulation 412.2.4.1 (v) Physicatseparation. 414.4,3 Every socket-outlet and luminaire supporting coupler in a SELV or PELV system shall require the use of a plug which is not dimensionally compatible with those used for any other system in use premises.
in the
same
Plugs and socket-outlets in a SELV system shall not have a protective conductor contact.
414.4.4
Exposed-conductive-parts
of SELV circuits shall not be connected to
Earth, or to prorecrive
conductors or exposed-conductive-parts of another circuit.
NOTE: If the exposed-conductive-parts of SELV
circuits are liable to come into contact, either fortuitously or intentionally,
with the exposed conductive-parts of other circuits, protection against electric shock no longer depends solely on protectiol by SELY but also on the protective provisions to which the latter exposed-conductive-pa(s are subjecr.
414.4.5 Ifthe nominal voltage exceeds 25 V AC or 60 V DC or ifthe equipment is immersed, basic protection shall be provided for SELV and PELV circuits by: (i) (ii)
insulation in accordance with Regulation 416.1
I
I
barriers or enclosures in accordance with Regulation 416.2.
Basic protection is generally unnecessary in normal dry conditions for:
(i) (ii)
SELV circuits where the non.fnal voltage does not exceed 25 V AC or 60 V DC PELV circuits where the nominal voltage does not exceed 25 V AC or 60 V DC and exposed-conductiveparts and/or the live parts are comected by a protective conductor to the main earthing terminal.
In all other exceed 12
if
I
the nominal voltage of the SELV or PELV system does not
VAC or 30 V DC.
415
NOTE:
cases, basic protection is not required
I
ADDITIONAL PROTECTION Additional ptotection in accordance with Section 415 may be specifled with the protective measure. In particular, additional protection may be required with the protective measure under cerlain conditions ofexternal influence and in cedail special locations (see the corresponding section of Part 7).
41s.1
4'15.1.1
Additional protection: RCDs
The use of RCDs with a mted rcsidual operating curent not exceeding 30 mA is recognized in AC systems as addilional protection in the er ent of failure of the provision lor ba:ic protect ion and or the provision for fault protection or carelessness by users.
I
I
I
73
to The use of RCDs is not recognized as a sole means of plotection and does not obviate the need apply one ofthe protective measures specified in Sections 411 to 414.
415.1,2
415.2
Additional protection: supplementary protective equipotential bonding
I
NOTE 1: Supplementary protective equipotential bonding is considered as an addition to fault pfotection. NOTE 2: The use ofsupplementary plotective bo[ding
example protection agaimt fire, thennal stresses in equipment, etc'
NOTE 3: Supplementary protective bonding may involve the entire instailatioq a paft equiplnent, or
a
I
for
I
of the installation, an jtem of
I
does not exclude the fleed to disconnect the supply for othel leasons.
location.
of Pafi 7), or for othcr NOTE 4: Additional requirements llray be necessary for special locations (sce the corresponding section teasolls.
exposedSupplementary protective equipotential bonding shall include all simultaneously accessible metallic the main practicable where including conductive-parts oifixed equipment and exiraneous-conductive-parts to the be connected shall system bonding reinforcement of constructional reinforced concrete. The equipotentiat protective conductors ofall equipment including those of socket-outlets'
415,2.1
The resistance R between simultaneously accessible exposed-conductive-pafs and extaneousconductive-parts shall fulfil the following condition:
415-2.2 i R:
R
in AC systems
V/Ia 120 v/Ia
50
in DC systems
where Ia is the operating current in amperes (A) ofthe protective device or:
(D (ii)
416
for RCDs.
Im
for overcurrent devices, the 5 s operating cutrent'
PROVISIONS FOR BASIC PROTECTION as a part Provisions for basic protection provide protection under normal conditions and are applied where specifled of the chosen Protective measure.
NOTE:
416.1
Basic insulation of live parts
Live pa s shall be completely covered with insulation which can only be removed by destruction. FoI equipment, the iniulation shall comply with the relevant standard for such electrical equipment' aIe generally The insulation is intended to prevent cottact with live parts. Paint, varnish, lacquel oI similal products service' protection in normal for basic adequatc inslllation not considered to provide
NOTE:
I
416.2 NOTE:
Barriers or enclosures
Baniers or enclosures are intelded to prevent contact with live pafis
Live parts shall be inside enclosures or behind baniers providing at least the degree of protection IpXXB orlP2X exceptthat, where largeropenings occurduring the leplacement ofpalts, such as cefiain lampholders to the or fuses, or where larger openings aie ,"""ttury to allow the proper functioning of equipment according
4,16.2.1
relevant requirements for the equipment:
(i) (ii)
touching live pafis, suitable precautions shall be taken to prcvent percons or livestock from unintentionally and through the opening as far as is reasonably practicable, persons will be aware that live pa s can be touched and should not be touched intentionally, and
(iii)
for the opening shall be as small as is consistent with the lequilement for proper functioning and replacement ofa Paft.
416.2.2
A horizontal top sudace of
a
barier or enclosure which is readily accessible shall provide
a degree
ofprotection of at least TPXXD or IP4X. A barrier or enclosure shall be firmly secured ir place and have sufficient stability and durability to known conditions of maintain the required degree of protection and appropdate separation from live pafis in the normal service, taking account ofrelevant extemal influences'
416.2.3
416,2'4
Where it is necessary to remove a barrier or open an enclosure or remove parts of enclosures, this
shall be possible only:
(i) (ii) (iii)
by the use ofa key or tool, or
after disconnection of the supply to live parts against which the barriers or enclosures afford protection, restoration ofthe supply being possible only after replacement or reclosure ofthe barrier or enclosur-e. or where an intennediate barrier providing a degree ofprotection ofat least IPXXB or IP2X prevents contact with live parts, by the use of a key or.tool to remove the intemediate barrier
NOTE:
This regulation does not apply to: a ceiling rose complying with BS 67 a cord operated switch complying with BS EN 60669-1 a bayonet lampholder complying with BS EN 61184 an Edison screw lampholder complying with BS EN 60238.
416.2.5 If, behind a banier or in an enclosure, an item of equipment such as a capacitor is installed which may retain a dangerous electrical charge after it has been switched off, a waming label shall be provided. Small capacitors such as those used for arc extinction and lor delaying the response ofrelays, etc shall not be considered dangerous.
NOTE:
Unintentional contact is not considered dangerous ifthe voltage resulting from static char€e falls below 120 V DC in less than 5 s after disconnection from the power supply.
417
OBSTACLES AND PLACING OUT OF REACH
417 .1
Application
The protective measures ofobstacles and placing out ofreach provide basic protection only. They are for application in installations, with or without fault protection, that are controlled or supervised by skilled persons.
The conditions ofsupervision under which the basic protective provisions of Section 417 may be applied as part the protective measure are given in Regulation 410.3.5.
417.2 NOTE:
of
Obstacles
Obstacles are intended to prevent unintentional contact with live parts but not intentional contact by deliberate circum\ ention ol lhe obslacle
417.2.1 Obstacles shall preyent: (i) unintentional bodily appr.oach to live pafis, and (ii) unintentional contact with live parts during the operation of live equipment in nonnal service. 417 .2.2 An obstacle may be removed without the use of a key or tool but shall be secured so as to prevent unintentional remoyal.
417.3 NOTE:
Placing out of reach Protection by placing out ofreach is intended only to prevent unintentional contact with live pafis.
A bare or insulated overhead line for distribution between buildings and structures shall be installed to the standard required by the Electdcity Safety, Quality and Continuity Regulations.
417.3.1
Simultaneously accessible pafts at different potentials shall not be within arm's reach.
A bare live part other than an overhead line shall not be within ann's reach or within 2.5 rr ofthe followins: tit An erpo:ed-conducli\ e-parl
(ii) (iii)
An extraneous-conductive-pat Abare live part ofany other circuit.
NOTE:
Two parts are deemed to be simultaneously accessible if they are not more than 2.50 m apart (see Figure 417).
417.3.2
Ifa notmally occupied position is restricted in the horizontal direction by an obstacle (e.g. handrail, mesh screen) affording a degree ofprotection less than IPXXB or IP2X, arm's leach shall extend from that obstacle. In the overhead direction, arm's reach is 2.50 m from the surface, S, not taking into account any intennediate ".bstacle
NOTE:
providing The values
a degree
ofprotection less than IPXXB.
ofann's reach apply to contact directly with bare hands wrthour
assisrance (e.g. rools or lcdder).
75
Fig 417
S=
- Arm's reach
surface expected lo be occupied by persons
limil of arm's reach
The values refer to bare hands without any assistance, e.g. from tools or a ladder.
Lequired by
handted' the distances ln places where bulky or lorg conductive objects are-notmalll dimensions ofthose objects relevant t"tti"g u"count olthe Regulations 4l T.3 l and + r;.: z slail tre int'-"u"A'
4lT.3.S
WHERE-THE INSTALLATION PROTECTIVE MEASURES FOR APPLICATION ONLY rHi supenvtstot't oF SKILLED oR INSTRUcTED
418
ist
uNDER
PERSONS
NorE:
protectjve provisions The conditioN of supeNision under which the fault 3 6' 410 given in Regulation are protective measule
ofscclion 418 may bc applied as par ofthe
Non-conducting location
418.1
application' This method ofprotection is not recognized for general NoTE:Thisprotectivemeasweisintendedtopreventsimultaneouscontactwithpartswhichmaybeatdifferentpotefltials through failure ofthe basic insulation oflive parts'
4,18',l,lAllelectricalequlpmentshallcomplywithoneoftheprovisionsforbasicprotectiondescribedin Section 416.
418.,l.2Exposed-conductive-partsshallbearrangedsothatundelordinarycircumstancespersonswillnot come into simultaneous contact with:
(i) (ii)
twoexposed-conductive-parts,or an exposed-conductive-part and any extraneous-conductive-part
failure of the basic insulation of ifthese parts are liable to be at different potentials through
418.1.3
ln
a
conductor' non-conducting location there shall be no protective
a
live pafi'
-l 418.1.4
Regulation 418.1.2 is fulfilled ifthe location has an insulating floor and walls and one or more ofthe
following arrangements applies:
(i)
Relative spacing of exposed-conductive-pafis and of extraneous-conductive-parts as well as spacing
of
exposed-conductive-parts
This spacing is sufficient if the distance between two pafis is not less than 2.5 m; this distance may be reduced to 1.25 m outside the zone of arm's reach.
(ii)
Interyosition ofeffective obstacles between exposed-conductive-parts and extmneous-conductive-parts Such obstacles are sumciently effective ifthey extend the distances to be surmounted to the values stated in point (i) above. They shall not be corulected to Earth or to exposed-conductive-parts; as far as possible they shall be ofinsulating material.
(iii) lnsulation
or insulating arrangements of extraneous-conductive-pafis.
The insulation sha11 be of sufncient mechanical strength and be able to withstand a test voltage of at least 2 000 V Leakage curent shall not exceed 1 mA in normal conditions ofuse.
418.1.5 The resistance of insulating floors and walls at every point of measurement under the conditions specified in Part 6 shall be not less than: (i) (ii)
50 kQ, where the nominal voltage ofthe installation does not exceed 500 V, or 100 kO, where the nominal voltage of the installation exceeds 500
V
NOTE: If
at any point the rcsistance is less than the specified value, the floors and walls are deemed to be extraneousconductive-parts for the pur?oses ofprotection against elect c shock.
The affargements made shall be pemanent and it shall not be possible to make them ineffective. The '6 arrangements shall also provide protection where the use of mobile equipment is envisaged.
418.1
NOTE 1: Attention is drawn to the risk that, where elect cal installations are not under effective supervision, further conductive parts may be introduced at
a later date (e.g. mobile Class I equipment! or extraneous-conductive-parts such as metallic water pipes), which may invalidate compliance wirh Regulation 418.1.6.
NOTE 2: It is essential that the iNulation offloor and walls cannor be affected by humidity.
418'1.7
Precautions shall be taken so that extraneous-conductive-parts extemal to the location concemed.
cannot cause a potential to appear
I
I
Protection by earth-free local equipotential bonding
418.2
This method ofprotection shall be used only in special circumstances.
NOTE:
Earth-free local equipotential bonding is intended to prevent the appearance ofa dangerous touch voltage.
4'18.2,1
A11
electrical equipment shall comply with one of the provisions for basic protection described in
Section 416.
418.2.2
Protective bonding conductors shall interconnect every simultaneously accessible exposed-
conductive-part and extraneous-conductive-palt.
418,2,3 The local protective bonding conductors shall neither be in electrical contact with Earth directly, nor through exposed-conductive-parts, nor through extraneous-conductive-parts. NOTE:
Where this requirement camot be fulfiIled, protection by automatic disconnection ofsupply is applicable (see Section 411).
418.2.4 Precautions shall be taken so that persons entering the equipotential location cannot be exposed to a dangerous potential difference, in particular, where a conductive floor insulated from Ealth is connected to the eaflh-ftee protective bonding conductors. 418.2.5 in
a
Where this measure is applied, a waming notice complying with Regulation 514.13.2 shall be fixed prominent position adjacent to every point ofaccess to the location concemed.
418.3
Electrical separation for the supply to more than one item of current-using equipment
Where the measure is used to supply two or more items of equipment from a single source, a waming notice complying with Regulation 514.13.2 shall be fixed in a prominent position adjacent to every point ofaccess to the location concemed.
NOTE:
Electdcal separation of an individual circuit is intended to prevent shock curents thlough contact with exposedconductive-parts that may be energized by a fault il1 the basic insulation ofthe circuit.
77
4lS.3.lAllelectricalequipmentshallcomplywithoneoftheprovisionsfolbasicplotectiondescribedin Section 416.
4ls.3.2Plotectionbyelecticalseparationforthesupplytomolethanoneitemofequipmentshallbeachieved r,y.o',priun."*itr,alltherequirementsofSection+t:e*ceptRegulation4l3.l.2.at:dwiththerequirementsiD Regulations 418.3.3 to 8.
4ls.3.3PlecautionsshallbetakentoplotecttheSepalatedcircuitfromdamageandinsulationfailure. 418.3.4Theexposed-conductive-paftsoftheseparatedcilcuit.shallbeconnectedtogethelbyinsulated, or shall not be connected to the protective conductor non_eafibed protectir" bonoirg condr"iJrr. iu"t., aora,r"tors of aiy other circuit or to any extraneous-conductive-pafis'
"^pJ-"ori"oit"-parts Note to Regulation 413 3'6' NOTE:
See
418,3,5EverySocket-outletshallbeprovidedwithaplotectiveconductolcontactwhicbshallbeconnected 4' with Regulation 418 3 to the equipotentialionding system provided in accordance
*l'f:*:1
418.3.6
Except where supplying equipment with double -, 11',19::::,;tl|1i*11:tl"J.,'1"" i,J", a protective bonding conductor in accordance with Regulation 418.3.4
418.3.7
lf two faults
i; "".i""ii " *r.li,r.1;il;";
fed by conductors of affectlng two exposed-conductive-pafis occur and these are with Table 4 1 1 ' confondng time ,r* supply in a disconnection ifr"U Or*""t
""i 4lS.3.STheproductofthenominalvoltageofthecircuitinvoltsandlengthofthewiringSysteminmetles 500 m' ,t.ruit
rot
"^.""4
ACCORDING TO REGULATION PROVISIONS WHERE AUTOMATIC DISCONNECTION 411,3,2 IS NOT FEASIBLE
419 419.1
(i) (ii)
not exceed 100 000 Vm, and the length ofthe wiring system shall
where: Where automatic disconnection is not feasible in circumstances installed' or electronic equipment with limited short-circuit curent is a protective device the required disconnection times cannot be achieved by
the provisions of Regulations 419.2 and 419 3 are applicable'
voltage U0 greatel than 50 V AC or For iNtallations with power electronic convertors with nominal the output voltage ofthe source shall.be reduced to 120 v DC and where automatic drscinnection is not feasible, or Earth ofu fuult Uetween a Iive conductor and the protective conductor 50 V AC or 120 V DC or less in t},. -l)' """nt as appropriate (see BS EN 62471 in u tlrrr" u. giu.n i,., Regulation 41 1.3.2.2,411.3.2.3 or 41 1.3.2.4,
419.2
manufacturcr gives adequate methods for the initial The power electronic convertor shall be one for which the veridcation and periodic inspection and testing ofthe installation the time *P bt Except wherc Regulation 419 2 applies, if automatic disconnection 4'19.3 ::ll:]tl^in equipotential proteclive u, appropriate, supplementaly required by Regulation 45.3.2.2,i t.2 z I ot ir.l.l.q voltage between simultaneously accessible +ls.iandihe n"g.,tutio, *iit bo,ding shall be prorided in accordanc. 120 v DC' extraneous-coniuctive-parts shall not exceed 50 V AC or
.^p"r.i-"""4*,it"-pafis
and/or
CHAPTER 42 PROTECTION AGAINST THERMAL EFFECTS
CONTENTS 420.1
Scope
421
PROTECTION AGAINST FIRE CAUSED BY ELECTRICAL EQUIPMENT General requirements
421.1
422
PRECAUTIONS WHERE PARTICULAR RISKS OF FIRE EXIST General
422.1
422.2
Conditions for evacuation in an emergency Locations with risks of fire due to the nature of processed or stored materials Combustible constructional materials Fire propagating structures
422.3 422.4 422.5 422.6
Selection and erection of installations in locations of national, commercial, industrial or public significance
423
PROTECTION AGAINST BURNS
424
PROTECTION AGAINST OVERHEATING Forced air heating systems, appliances producing hot water or steam, and space heating appliances
424.1
CHAPTER 42 420.'l
Scope
This chapter applies to electrical installations and equipment with regard to measures for the protection ofpersons,
livestock and property agai st:
(i) (ii) (iii)
the harmful effects ofheat or thermal radiation developed by electrical equipment the ignition, combustion or degradation ofmaterials flames and smoke where comparhnents, and
(iv)
a
fire hazard could be propagated ftom an electrical installation to other nearby flre
safety services beilg cut offby the failure ofelectrical equipment.
NOTE 1: Fol protection against thermal effects and fire, statutory requirements may be applicable. Refer to Appendix 2. NOTE 2: Protection against overcurent is dealt with in Chapter 43 ofthese Regulations.
421
PROTECTION AGAINST FIRE CAUSED BY ELECTRICAL EQUIPMENT
421.1
Generalrequirements
121.1.1
Persons, livestock and property shall be protected against harmful effects ofheat or fire which may
r3 generated or propagated in electrical installations. \farufacturers' instructions shall be taken into account in addition to the requirements of BS 7671. NOTE 1: Harmful effects ofheat or fire may be caused by:
-
-
\:-E
heat accumulation, heat radiation, hot components or equipment
failure ofelectrical equipment such as protective devices, switchgeat themostats, temperature limiters, seals of cable penerralions and u iring cyslems overcunent insulation faults or arcs. sparks and high temperatre particles
harmo
c crurents
extemal influences such as lightning surge inappropriate selection or erection ofequipment.
2l Lightning strikes and oveNoltages are covered in BS EN 62305 and Section 443 ofthese Regulatiors.
Fixed electrical equipment shall be selected and erected such that its temperature in nolmal operation
79
will not cause a fire. This shall
by additional protective measures be achieved by the construction ofthe equipment or
taken during erection
material or to not cause danger or harmful effects to adjacent fixed The heat generated by electrical equipment shall *at"rial .it i"h -ay ioreseeably be in proximity to such equipment'
Wherefixedequipmentmayattainsurfacetemperatureswhichcouldcauseafirehazardtoadjacentmaterials'ore The equipment shall: ilr" r"rr"wing initallation methods slall be adopted.
"i "r."r. (i)bemountedonasuppotwhichhaslowthermalconductanceolwithinanenclosurewhichwillwithstand. tempemtures with [rinimal risk of tire or harmful thermal effect' such
as may be generated'
or
(ii)bescreenedbymatedalsoflowthermalconductancewhichcanwithstand.withmininlalriskoffileor
' '
equipment' or harmful therm'al effect, the heat emitted by the elecffical
(iii)bemountedSoaStoallowsafedissipationofheatandatasutEcientdistancefromadjacentnraterialon r,*. deletedous effects. Any means of suppofi shall be of lorv themal which such tempemtures conductance.
"ouio
zljl.SWherearcs,spalksorpafiiclesathightemperatuemaybeemitted-byfixedequipmentinnomal requirenrents ltshallbe: ,"rria", *" aqrip-ent shall meet one tr more ofthe following
(i) (ii)
totally enclosed in arc-resistant matedal
effects upon which the emissions could have harmflil screened by arc-resistant material from materials
.iii)mountedsoastoallowsafeextinctionoftheemissionsataSufficientdistanceflommaterialsuponwhich the emissions could have harmful ellects
(iv)
in compliance with its standard'
and shall be non-ignitable, of low thermal conductiYity Arc_resistant material used for this prctective measure adequate thickness to provide mechanical stabiliry
of
42l.,l.4Fixedequlpmentcausingaconcentrationandfocusingofheatshallbeatasu{ficientdistanceflom a dangerous temperature in ,rrui ir,. object or element is not subjected to
any fixed object or building
normal conditions.
"r"rr"ii-ri
42l.,l"5Wheleelectricalequipmentinastnglelocationcontainsflamn,ubleliquidinsignificantquantity, products ofcombustion' tut"i.'-ii fttvent the sireaa of tiquid' flarre and the
adequate precaution, ,nuff U"
NOTE 1: Exarrples ofsuch precautions are: and provide extinction in the event of fire (a) a retention pit of sufncieDt size to collect any leakage of liquirl provision of sills or othel means in o .rrur"ter of adequateire-resistance and the (b) iNtallarion ofthe being ventilated solely to "quip-.ni a chambel ofthe building, such ofpreventing burnin!-il'or,a'ro."uo.* a other palts the exterial atmosPhere' quantity is 25 litres' NOTE 2: The generally accepted lower limit for a signiicant
NOTE3:Forquantitieslessthan25litles,itissufncienttotakeprecautionslopreventtheescapeofliquid' to be smoke and gasNOTE 4: Products of combr-rstion ofliquid are considercd
421.1,20,|Withindomestic(household)premises,consumerunitsandsimilarswitchgearassembliesshall comply with BS EN 61439-3 and shall: (i) have their enclosure manufactured from non-combustible material' or co,rplying withRegulation (ii) be enclosed in a cabinet or enclosure constructed ofnon-combustible material and 132.12.
NOTE:
Ferrous metal,
e.g steel, is deemed to be
an example
ofa non-comhustible material'
42l.l.6Matedalsusedtbltheconstructionofenclosuresofelectricalequipmentshallcomplywiththe ,oiatura"tot.,"utundfirerequirementsinanappropdateproductstandard' likely to be enclosure shall withstand the highest temperature where no product standard exists, the materials ofan produced by the electdcal equipment in nomal use'
42l,l.TArcfaultdetectiondevicesconformingtoBSEN62606arerecommendedasameansofproviding
in AC final circuits' additional protection against fire caused by arc faults
If used, an AIDD shall be placed at the origin ofthe circuit to be protected. NOTE: Examples ofwhere such devices can be used include: premises with sleeping accommodation
locations u.ith a risk offire due to the nature ofprocessed or stored materials, i.e. BE2 locations (e.g. bams
woodworking shops, stores of combustible materials) locations with combustible constructional materials, i.e. CA2 locations (e-g. wooden buildings) fire propagating strucrures. i.e. C82 locations
locations with endangering of ireplaceable goods.
422
PRECAUTIONS WHERE PARTICULAR RISKS OF FIRE EXIST
422.',|
General
The requirements ofthis regulation shall be applied in addition to those of Section 421 for installations in locations wherc any olthe conditions of extemal influence described in Regulations 422.2 to 6 exist.
Except for wiring systems meeting the requirements of Regulation ,122.3.5. electrical equipment shall be restricted to that recessary to the use ofthe locations given in Regulation 422.1.
422.1.1
422,1,2
Electrical equipment shall be so selected and erected that its nonnal temperature rise and foreseeable temperatur e rise dudng a fault cannot cause a fire. This shall be achieved by the constmction ofthe equipment or by additional protective measures taken during erection. Special ureasures are not necessary where the temperature of surfaces is unlikely to cause combustion ol nearby substarces.
422.1.3 422.2
A temperature cut-out device shall have manual reset only.
Conditions for evacuation in an emergency
The following regulations refer to corditions:
BD2: Low density occupation, difficult conditions ofevacuation BD3: High density occupation, easy conditions ofevacuation BD4: High density occupation, difficult conditions of evacuation. (Refer to Appendix 5.)
NOTE:
Authorities such as those responsible fol building construction, public gatherings, fire prevention. hospitals, etc. may specify whicir BD condition is applicable.
422,2,1 Cables shall not encroach on escape routes unless they meet the recommended requirements ofthe relevant pafi ofBS EN 60332-3 series and achieve at least 60 % light tansmittance when tested in accordance with BS EN 61034-2. Cables in escape routes shall be as shofi as practicable. Cables encroaching on escape routes shall not be installed within arm's reach unless they are provided with protection against mechanical damage likely to occur during an evacuation. Where used, cable rnanagement systems shall be one or nrore ofthe following types:
(i) (ii) (iii) (iv)
l
conduit systems classified as non-flame propagatirg according to BS EN 61386
I
cable trunking systems afld cable ductirg systems classified as non-flame propagating according to BS EN 50085 cable tray and cable ladder systems classified as non-flame propagating according to BS EN 61537, or
I
powetrack systems meeting the requirements olBS EN
I
NOTE:
Cabies need to satisfy the requirements
6153,1.
ofthe CPR in respect oftheir reaction to lire.
See
Appendix 2. item l7-
I
Cables that are supplying safety circuits shall have a resistance to fire rating of either the time authorized by regulations for building elements or Blitish Standards for the circuits or one hour in the absence of such a regulation or standard.
422.2.2 In conditions BD2, BD3 or BD4, switchgear or conrolgear shall be accessrble only to authodzed persons. If switchgear or controlgear is placed in an escape route, it shall be enclosed in a cabinet or an enclosure constructed of non-combustible or not readily combustible material.
I
These requirements do not apply to items ofswitchgear or controlgear installed to facilitate evacuation, such as fire
alam call points.
81
422.2.3
ln
escape routes where conditions
equipment contarmng BD3 or BD4 exist' the use of electrical
flammable liquids is not permitted'
in in equipn.rent' such as a capacitor installed to individual capacitors incolporated This requirement does not apply stalter' a discharge luminaire or a motor
422.3
materials the nature of processed or stored Locations with risks of fire due to
Therequirementsofthislegulationshallbeappliedinadditiontothoseofsection42linlocationswheleBE2 conditions exist.
Thisregulationdoesnotapplytoselectiooanderectionofinstallationsinlocationswithexplosionrisks' t.. eS [fn 000'q- l4 and BS t N 6l 241 - l4 NoTEI:BE2conditionsexiSt$'herethereisariskoffireduetothenanufacfure,processiogorstorageofflanrmablen,raterials (see Appendix 5)' ircluding the preserce ofdust of dust alld fibres)' bams (dre to the accumulation presenting BE2 conditions include locations materials)' of Examples 2: ofcombustible NOTE iJr" . *e storage and processins woodwo*ing facilitier, r"o"J]iii iio"*ti"i""i"r". NoTE3:QuantitiesofflammablematerialsoltheSulfaceolvolumeofthelocationmayberegulatedbynationalauthorities' specifies requirements' a luminaire which an appropdate product standard b1 the manu facturer' 422.3.1 Except for equipment for *,rfrr"itil U n less otherw ise recotnrnended .ri.ri.ls. isrance'floil d uare ,ha ll be kept at an adeq from combustible materia]s: iJln*ii"J"t it-I" i"lt"*ing niini1nu'; di'tunce a small spotlight or p'ojt"to'
'r.'u[
(i) (ii) (iii)
Rating uP to
100
W
Over 100 and uP to 300 W Over 300 and uP to 500 W
0.5 m
0'8 m 10
m'
mechanical 5ts55gs Such shall be protected against foreseeable luminaires of in components other Lamos and r"'* it"gtal part of the luminate or are fltted nrotective means shall not be fixed tlriHil""lder;;'1;J ions I..ordrna. *i'f,t the mattufacntrer's instrucl
"v
"'
AluminaireWithalampthatcouldeiectflammablematelialsincaseoffailureshallbeconstructedwithasafety manulacturer's insrructions'
;;;.:i'-.'.r,;i; ;,it.'t tn'p in uttoiountt
u irh the
422.3'2MeasulesshallbetakeltopreventanenclosureofelectricalequipmentSuchaSaheaterollesistol from exceeding the following temperaturcs:
(i) (ii)
90'C under normal conditions' and 115 "C under fault conditions
ahove' Wherematerials.uchaSduslorhbressullcienrrocauseafirehazardcouldaccumulaieonanenclosureofelectrical *t tntto'u" fro'n t*cteding the temperatures staled
*"u""' 'hull'it'*li"i" 0"""t have limited surface temperature I-r.*t'"t marked p in comnliance with BS EN 60598-2-24
equiprnent. -' adequata
,f#, 4?2.3.3
unless: be installed outside the location Switchgear or controlgear shall
or dust' or at least rP4x or' in the presence
lllil'J* *",.-g a degree t"l,T':::y 422 3 lI applies' ll lP5Xil['',':.'T']i o"'Jti'it"iili'"i"t'i' a"'t' tet'x' except where Regulation or' in the "t"ntt of BS EN 60332-1-2 422.3.4 A cable shall as a mirimum meet the tequirements * plaster or concrcte or otherwise Protected embedded in non-combustible ryt:yl^'Tl I,i.,
A cable not completely
fromflreshallasaminimummeetthelequirementsofBsEN60332-1-2. in BS EN 61386under flre conditions specifled A conduit system shall satisry the test
1'
AcabletrunkingsystemolcableductingsystemslrallSatisfythetestundelfiIeconditionsspecifiedintheapplopdate pan
olthe
BS EN 50085 series
specified in BS EN 61537' satisfy the test under flrc conditions A cable tray system or cable ladder shall part ofthe specified in the appropriate propagation the test for resistance to ffame A powefirack system shall satisty BS EN 61534 series'
wiingsystemsshallbeselectedarrdinstalledtominimizQthepropagationofflame.
lr
Whcrc the risk of flame propagation is high the cable shall nrect the reqLrilemcnts of the appropdate pafi of BS EN 60332-3 serics. NOTE 1: The risk offlarne plopagation can be high where cables
ar-e
bunchcd or installed in long vertical
rLLns
NOTE 2: Cables manulactured for the above application also nccd to satisfy the requirements of the CPR in respect of their 'eactron to nre. See Appendl\ 2. itetn l'.
Awiling
422.3.5
system which passes through the location but is not intended to supply electrical equipment
in the location shall:
(i) (ii)
meet the requirements of Regulation 422.3.4, ar.d have no connection orjoint within the location, unless the connection orjoint is installed within an eflclosure that does l]ot adversely affect the flame propagation characteristics ofthe widng system, and
(iii) be protected against overcurrent in accordance with (iv) not employ bare live conductors.
422.3.6
the requirements ofRegulation 422.3.10, and
Not used
422.3.7 A motor.which is automatically or remotely cortrolled or which is not continuously superuised shall be protected against excessive tenperatue by a protective device with manual reset. A motor shall be protected against overtemperature in all operational modes. 422.3.8 Lrerylurninaire.hall: (i) be appropriate for the location, and (ii) be provided with an enclosure providing
a degree ofprotection
ofat least IP4X or, in the
presence ofdust,
IP5X or, in the presence ofelectrically conductive dust, IP6X , and
(iii) have a limited surlace temperature in accordance with BS EN 60598-2-24, and (iv) be ofa type that prevents lamp components from falling from the luminaire. ln locations where there may be fire hazards due to dust or fibres, luminaires shall be installed
so that dust or fib1es
cannot accumulate iu dangerous amounts.
422.3.9
Wiring sysrems, other than mineral insulated cables, busbar trunldng systems or poweftrack systems, protected against insulation faults: shall be (i) in a TN or TT system, by an RCD having a rated residual operating cun'ert (l^n) not exceeding 300 rLA according with Regulation 531.3.2 and to relevant product standards
\\'here a resistive fault may cause a lire, e.g. for overhead heating with heating film elements, the rated residual operating cunent shall not exceed 30 mA. (ii) in an IT system, by an insulation monitoring device with audible and visual signals provided in accordance with Regulation 538.1. Disconnection times in the event of a second fault are given in Chapter 4t. Altematively, RCDs with a rated residual operating curent as specified in (i) rnay be used. In the event ofa second fault, see Chapter
4l
for disconnection times.
422.3.10
Circuits supplying or traversing Iocations where BE2 conditions exist shall be protected against ' erload and againsl fault cun ent by protecti\ e devices located outside and on the supply side of these locations. Circuits originating inside these locations shall be protected against overcurrent by protective devices located at .
:eeir origin.
422.3.11 Regardless ofthe nominal voltage ofa circuit supplied at extra-low voltage, live pafis shall be either: (i) contained in enclosures affording a degree ofprotection ofat least IPXXB or lP2X, or (ii) provided with insulation capable ofwithstanding a test voltage of500 V DC for 1 minute These requirements are in addition to those ofSection 414.
422.3.12 422.3.13
A PEN conductor shall not be used. This requirement does not apply to
a
circuit traversing the location.
Except as pennitted by Regulation 461.2, every circuit shall be plovided with a means ofisolation
iom all Iive supply conductors by a linked switch or a linted circuit-breaker' NOTE: Provision may be made for isolation ofa group ofcircuits by a comlnon means, if the service
conditions allow this.
83
following construction: Flexible cables shall be ofthe V' or rating ofnot less than 450/750 Heavy duty t1'pe havtng a voltage
422,3.201
(i) iiij
,ultuUty prot"cted againsl mechanical
damage
FN
50s65-1.
I
NoTEI:Descriptionsoflight,oldinaryaodhealrydutytypesarecivei:::.8N505651 (cooventional elastome c tlpes) foooa in BS EN 50525-2-21 u" ttry heavy flexible NOTE2: ""int "un types)' '-- - -' Suitable
and
gS UN tOt25-3-21 (low smoke' halogen-free
fixed' A heating appliance shall be
422.3.202
dusts or fibres the ignition of combustible a rype which prevents of be shall 422.g.2O3 A heat storage appliance by the heat stodng core'
422.4
Combustibleconstructionalmaterials
Therequirementsofthisregulationshallbeappliedinadditiontothoseofsection42linlocationswhereCA2 (see conditions exist' materials' such as wood constructed of combustible mainly is building a NOTE: CA2 collditions exist where orceilings ln does not ignite walls''floors
I
'o
electrical equipment X*j]'tions shall be taken so that * i'ing ty"t*' int;"ding utt;ttotitt' utt boxes and enclo:ures orr.o., u p"-l*ruttto erectton' nrelabricated hollo\\' u alls contarni'.'! *url is liable to be dritled during rpii'*ht" ;il :if;1 protecttt" of degree a 'rtt .hull hur.
prodll1"'#Si;eT::'iil""'JJ;[ffi:t;;nl'f,lT:
which an appropriate Except ror equipmenl for ibte materia'' combusr lrom distance the follou ing m:nrr 'o;quare ", piojector shall be installed al
422.4.2
,'il1ii.-0.r, l'",.ri .ri,utnt
ul':ilil.jff;..],"n,, i"'u"iiure
"t
(ir)
Rating uP to 100 W Over 100 and uP to 300 W
(iii)
W Over 300 and uP to 500
(i)
materials;
0.5 m 0.8 m 1.0
m. 511s55s5 Such
againsr foreseeable mechanical luminaires shall be prolecled are fitted in I amos and Other componenrs o[ fo* u" i""gi'i p'; "r 'he luminaire or *'t'i ti'it'on"'ot" lixed be nol .,.,recLir e means shall 'hty ins!ruclions' ilo.Janie * ith tht 'nunuluct"er') be construcred u;tr a sarett
A ru ninaire with a
I
ramp,that:.oliti:;:JTT;l[fi';:'Ji.:T;:il:l::'.*''
i
'J:i':]"-'j:::ff':iT:JJ-;:'tril*il;';";;;ins.,arionormounring"""::"llT:':'::i-"' installed on or in a combustible g installation
bo*t.11-*::):1::
e 422.4.201 Electrical equipment'tt'ioard for enclosure tempemture Iir'riln", ."-ot, *itt.' tt'" itit'*t
i
boards'
,
flse'
be enclosed with
a
Regularion 422.4201 shall thal does nor compry wirh lrom electrical equipmenr Erecrrical 422.4,202 nru,.r*i"on r-ttt itut ttittipution ni.,..ri Ji.' ru rhicLness ot non-nur "rr*i "r,n.
i i I
it.
.uitable
into account' equipment shall be taken
422.4,203
of BS EN 60332-1-2' to fire i,,, respect oftheir reaction
the requirements Cables shall comply with ofthe cpR also n"ed to.utisfy th"."quirements
see Appendix
2' item 17'
l
I
NorE: cabies 61386-l and BS EN 50085-l accordance with BS L'N in be shall s)slems 422.4.204 Conduit and trunking standards' tf" t'"-'"ttiiuntt *sl: wilhin lhese respectir ely and shall meet
422.5
,
l
Fire propagating structures appropriate
oIthe TherequiretnentsoIthisregulatron.hallbeappliedinaddiriontolhoseoIsection42Iinlocations$hereCB2 nigh rhe caure sia ;.iiit',. "quitttn"ntt or$'ari rist< or"r#i"" the $ here isr. condirions er ', lacililale pan ol'BS fN 00332-3 series and dimensrorl: \ hich ^'4"^ '-'r ayict uhere a building ha' a shape
I
ffi;,:ru:y:;ilJ::[:xi[u:]?:l:Tjfl:ill1::;1il11*;:;";;'"dinghasarorcedvenilaron\vsem tsee APpendix
5l'
NoTE2:Firedetectolsmaybeprovidedtoactivatemeasuresforpreventingpropagationoffire,forexample'theclosing or trunking' ''"'- -'"ri*ro"f shutters in ducts' troughs
I
NOTE 3: Boxes and erclosures according to BS EN 60670-l and BS EN 61439 series for use in hollow walls can be used.
I
NOTE 4: Cables also need to satisly the requirements ofthe CPR in respect oftheir reaction to fire.
I
See
Appendix 2, item 17.
422.5.1
In structures where the shape and dimensions are such as will facilitate the spread offire, precautions shall be taken so that the electdcal installation does not propagate a fire (e.g. chimney effecr).
Selection and erection of installations in locations of national, commercial, industrial or public significance
422.6
The requirements of Regulation 422.1 shall apply to locations that include buildings or rooms with assets of significant value. Examples include national monumentsj museums and other public buildings. Buildings such as railway stations and airports are generally considered to be ol public significance. Buildings or facilities such as laboratories, computer centres and cefiain industrial and storage facilities can be of commercial or industrial significance. The following measures may be considered:
(i) (ii) (iii) (iv)
Installation ofmineral insulated cables according to BS EN 60702 Installation of cables with improved fire-resisting characteristics in case of a fire hazard, such as those complying with BS 7629-1, BS 7846 or BS 8573 Installation ofcables in non-combustible solid walls, ceilings and floors lnstallation ofcables in areas with constructional partitions having a fire-resisting capability for a time of 30 minutes or 90 minutes, the latter in locations housing staircases and needed for an emergency escape.
Where these measures are not practicable improved fire protection may be possible by the use of reactive fire protection systems.
423 423.1
PROTECTION AGAINST BURNS Excepting equipment for which
a
Harmonized Standard specifies
:art offixed electrical equipment within am's reach shall not attain
a
limiting temperature, an accessible jn cxccss ofthe approptiate Iimit
a temperatlLre
.tated in Table ,12.1 . Each such parl of tl']e fixed instaliation likcly to attain under normal load conditions, evcn tbr a :hofi period, a temperature exceeding thc appropriate limit in Table .12.1 shall bc guardcd so as to prevent accideltal :Lrrtact.
TABLE 42.1 _ Temperature limit under normal load conditions for an accessible part of equipment within arm's reach Accessible A hand-held pan
Material of accessible surfaces
Maximum temperature ("C)
Metallic
55
Non-metallic
65
L paft intended to be touched but not
Metallic
70
hand-heid
Non-metallic
80
A part which need not be touched for nomal operation
Metallic Non-metallic
90
80
124
PROTECTION AGAINST OVERHEATING
124.1
Forced air heating systems, appliances producing hot water or steam, and space heating appliances
::::L)rls containing forced air heating systems, appliances producing hot water or steam, and space heating :nces. rrLrst comply with the approp ate parts ofthe Buiiding Regulations.
---3-.
85
CHAPTER 43 PROTECTION AGAINST OVERCU RRENT CONTENTS 430
INTRODUCTION
430.1
430.2
Scope Not used
430.3
General requirement
431.2
OF THE CIRCUITS AND THE PROTECTION ACCORDING TO THE NATURE DISTRIBUTION SYSTEM Protection of line conductors Protection of the neutral conductor
431.2.',1
TN or TT system
431.2.2
lT system
431.2-3
Harmonic currents Gonductor Disconnection and reconnection of the neutral
43',| 43',1.',1
431.3
432.3
NATURE OF PROTECTIVE DEVICES current Protection against both overload current and fault Protection against overload current only Protection against fault current only
432.4
Characteristics of protective devices
432 432.1 432.2
433 433.1 433.2 433"3 433.3.1 433.3.2 433.3.3 433.4 433.4.1
433.4.2
434 434.1
434.2
434.3 434.4 434.5
43s 435.',|
435.2
436
PROTECTION AGAINST OVERLOAP CURRENT protective device Co-ordination between conductor and overload Position of devices for protection against overload Omission of devlces for protection against overload General overload in lT systems Position or omission of devices for protection against safety reasons for omission of devices for protection against overload Overload protection of conductors in parallel Equal current sharing between parallel conductors Unequal current sharing between parallel conductors PROTECTION AGAINST FAULT CURRENT Determination of prospective fault current Position of devices for protection against fault current current Omission of devices for protection against fault parallel in conductors Fault current protection of Characteristics of a fault current protective device
AND FAULT CURRENT PROTECTION CO-ORDINATION OF OVERLOAD CURRENT Protection afforded bY one device Protection afforded by separate devices OF THE SUPPLY LIMITATION OF OVERCURRENT BY THE CHARACTERISTICS
CHAPTER 43 PROTECTION AGAINST OVERCU RRENT 430
INTRODUCTION
430.1
Scope
This chapter provides requirements lor the protection of live conductors from the effects ofovercuaent. This chapter describes how live conductors axe protected by one or more devices for the autornatic disconnection of the supply in the event of overload current (Section 433) and fault current (Section 434), except in cases where the overcurrent is limited in accordance with Section 436 or where the conditions described in Regulation 433.3 (omission ofdevices for protection against overload) or Regulation 434.3 (omission ofdevices for protectior against fault cur.rent) are met. Co-ordination of overload curent protection and fault curert protection is also covered (Section 435). NOTE
1
: Live condLrctors protected against overload cullellt in accordance with Section 433 are also considered to be ptotected against faults likely to cause overcuaents ofa magnitude similar to overload currents-
NOTE 2: The Iequirements ofthis chapter do not take account ofextemal i[fluences. NOTE 3: Protection ofconductors according to these regulations does not necessarily protect the equipment connected to the conductols.
NOTE 4: Disconnection does not necessadly mean isolation in this chapter.
430.2
/Vof used
430.3
General requirement
A protective device shall be provided to break any overcurrent in the circuit coltductors before such a current could cause a danger due to thermal or mechanical effects detrimental to insulation, connections, joints, teminations or the surroundings of the conductors. The protection against overload current and the prctection against fault current shall be co-ordinated in accordance with Section 435.
NOTE;
An overcunent may be an overload current or
431
a
fault current.
PROTECTION ACCORDING TO THE NATURE OF THE CIRCUITS AND THE DISTRIBUTION SYSTEM
Protection of line conductors
431.1
431.1.'l
Except where Regulation 431.1.2 applies, detection of overcurent shall be provided for all llne
conductors and shall cause the disconnection ofthe conductor inwhich the overcurent is detected, but not necessarily the disconnection of the other line conductors except where the disconnection of one line conductor could cause damage or danger
If
disconnection of a single line conductor may cause danger, for example in the case of a three-phase motor,
appropriate precautions shall be taken.
431.1.2
In a TN or TT system, for a circuit supplied between line conductors and in which the neutml
conductor is not distdbuted, overcurent detection need not be provided for one ofthe line conductors, provided that both the following conditions are simultaneousty fulfilled:
(i)
There exists, in the same circuit or on the supply side, differential protection intended to detect unbalanced loads and cause disconnection ofall the line conductors. and
(ii)
the neutal conductor is not distributed from an afiificial neutral point ofthe circuits situated on the load side
ofthe differential protective device mentioned in (i).
431.2 431.2:l
Protection ofthe neutral conductor TN or TT system
The neutral conductor sha1l be protected against short-circuit cunent.
Where the cross-sectional area of the neutral conductor is at least equivalent to that of the line conductors. and
87
to plovide the cufient in the neutral is not expected to exceed the value in the line conductols, it is not necessary for that conductor' device disconnecting or a collductor overcurent detection for the neutral
where the cross-sectional area of the neutral conductor is less than that of the line conductors, it is necessary to plovide overcurTent detection fol the neutlal conductol, appropriate to the cross-sectional area ol the conductol of the neutral The overcurent detection shall cause the disconnection of the line conductors, but not necessarily conductor conductol apply to Except for discorutection complying with Regulation 461.2 the requirements fol a neutral conductor.
a
PF'N
reler to Regulation Where the current in the neutral condLrctor is expected to exceed that in the line conductors 431.2.3.
431.2.2
IT system
The neutral conductor shall not be distributed unless one ofthe following is met:
(i) Overcurent detection is provided for the neutral conductor of every circuit The overcurent detection
(ii)
(iii)
the neutlal shall cause the disconnection of al1 the live conductots of the coresponding circuit, including conductor protective device installed The padicular neutral conductor is effectively protected against shofi-cilcuit by a with Regulation 434 5 on the supply side, for example at the odgin ofthe installation, in accordance (lAn) not exceeding The particular circuit is protected by an RCD with a rated residual operating current shall disconnect The RCD coflductor. neutml the corresponding 0.2 times the currert_calrying capacity of shall have The device conductor neutral the including circuit. all the live conductors of the coresponding
su{Iicient bteaking capacity for all poles.
431.2.3
Harmoniccurrents
hamlonic content ovcrcu-rent detcction shall be provided for thc ncutral conductol i[ a polyphase circuit whcle the capacity ofthat ihe current-car'rying cxceecl nlay conductor leutral in the cuflent ofthe linc currents is such that the but not necessarily thc neutral contluctor. The ovcrcLL1.Ient detectio11 Shail causc cliscolnection ofthe ]ine concluctors applicable' 43 1'3 arc Regulation of rcquiremcnts the is disconnectcd concluctol. Where the neutral 43'1.3
Disconnection and reconnection of the neutral conductor
neutral where a switch is placed in a ncutral conductor, disconnection and reconnection shall be such that the
at the same time as or befbre concluctor shall not be disconnected before the line concluctors ancl shall be reconnected the line conductors.
432
NATURE OF PROTECTIVE DEVICES
A protective device shall be ofthe appropriate type indicated in Regulations 432 432.1
1
to 3'
Protection against both overload current and fault Gurrent
and fault current Except as pemitted by Regulation 434.5.1, a device providing protection against both overload the maximutn including shallie capable of breaking, and for a circuit-breaker rnaking, any overcurrent up to and prospective fault ctLrrent at the point wherc the device is installed'
432.2
Protection against overload current only
whose A clevice providing protection against overload curent is genemlly an invetse-time-lag plotective device point the at current plospective f'ault r.ated shori-cir.cuit Lreaking capacity n.ray be below the value ofthe maximum where the device is ilstalled. Such a device shall satisfy thc relevant requirements of section'133
432.3
Protection against fault current only
protection is achieved A device pr.oviding protection against fault curert only shall be installed where overload as permitted by Except with by other means o[ where Section 433 peruits overload protection to be dispensed cunent up to the fault making, Regulation 434.5. I , a device shall be capable of breaking, and for a circuilbreaker 434' of section Iequilements including the prospective fault current. such a device shall satisty the relevant ancf
NOTE:
8A
Such a dcvicc maY be:
(i) (ii)
a
circuit bieaker rvith
a fuse.
a
short-circuit rclease, or
Gharacteristics of protective devices
432.4
The time/current chatacteristics of an overcurrent protectiye device shall comply with those specified series, BS 3036, BS EN 60898, BS EN 60947 -2 ol BS EN 61009-L
ir
BS 88
The use ofanother device is not precluded provided that its time/curent characteristics provide a level ofprotectiol not less thar that given by the devices listed above.
433
PROTECTION AGAINST OVERLOAD CURRENT
433.1
Go-ordination between conductor and overload protective device
Every cilcuit shall be designed so that a small overload oflong duration is uulikely to occur 433.1.1
The opelating charactedstics of a deYice protectiug a conductor agailst overload shall satisfy the
following conditions:
(i)
The rated current or cuffent setting ofthe protective device (ln) is not less than the design curent (lb) ofthe
circuit, and
(ii) (iii)
the rated current or current setting of the plotective device (In) does not exceed the lowest ofthe curentcarrying capacities (1,) ofany ofthe conductors ofthe circuit, and
curent (12) causing effective opemtion ofthe protectiye device does not exceed L45 times the lowest the culTent-carrying capacities (lz) ofany ofthe conductors ofthe circuit.
the
of
For adjustable protective devices, the rated cunent (In) is the current setting selected.
The cunent (I2) causing effective operation of the protective device is given in the product standard or may be provided by the manufacturer. NOTE 1; Where over load protection is plovided by BS 3036 firses, refer ro Regulation 433.1 .202. NOTE 2: Protection in accordalce rvith tJris regulation rray not provide protection in overcurents less than 12 occur.
aLl cases,
for example. where sustaincd
433.1.201 Where the protective device is a general-purpose type (gG) fuse to BS 88-2, a fuse to BS 88-3. a circuit-breaker to BS EN 60898, a circuit-breaker to BS EN 60947-2 or a residual current circuit-breaker with integral overcurent protection (RCBO) to BS EN 61009-1, conpliance with conditions (i) and (ii) also results in compliance with condition (iii) ofRegulation 433.1.1. 433.1.202
Where the protective device is a semi-enclosed fuse to BS 3036 compliance with condition (iii) of . I is afforded if its rated current (In) does not exceed 0.725 times the current-carrying capacity (lz) ofthe lowest rated conductor in the circuit protected.
Regulation 433.1
433.1.203 For direct buried cables or cables in buried ducts where the tabulated current-carrying capaciry is based on an ambient tempemture of 20 "C compliance with condition (iii) of Regulation 433.1.1 is afforded if the rated current or current setting ofthe protective device (ln) does not exceed 0.9 times the cufient-cafl'ying capacity (lz) ofthe lowest rated conductor in the circuit protected.
433.'1,204 Accessories to BS 1363 may be supplied thlough a ng final circuit, with or without unfused spurs, protected by a 30 A or 32 Aprotective device complying with BS 88 se es, BS 3036, BS EN 60898, BS EN 60947-2 or BS EN 61009-l (RCBO). The cilcuit shall be wired with copper conductors having line and neutml conducto$ with a minimum cross-sectional area of 2.5 mmr except for two-core mineral insulated cables complying with BS EN 60702-1, for which the mininurl cross-sectional area is 1.5 nrmr. Such circuits are deemed to meet the lequircments of Regulation 433.1. t if the current-carrying capacity (tz) ofthe cable is not less than 20 A and if, under the intended conditions ofuse, the load curent in any paft olthe circuit is unlikely to exceed lbl long periods the curent-canling capacity (lz) ofthe cable. Position of devices for protection against overload
433.2
433.2.1 Except where Regulation 433.2.2 or 433.3 applies, a device for protectior against overload shall be ilstalled at the poilt rvhere a reduction occul's in the value ofthe cLtrrent-carrying capacity ofthe conductors ofthe installation.
NOTE:
A |eduction in cuffeot-caffying capacity l1lay be due to a charge in cross-sectional area, lnethod of installation. tlpe ofcable or conductor. or i11 e[vironmental conditions. I
I
I 8-o
I
The device protecting a conductor against overload may be installed along the run ofthat conductor if the part of the run betwein the point where a change occurs (in cross-sectional area, method of installation, type has neither branch of cabje or conductor, or in environmental conditions) and the position ofthe protective device conditions; following least one ofthe at and fuIfils circuits nor outlets for connection of current-using equipment (i) It is protected against fault curent in accordance with the requirements stated in Section 434
43Z.Z,Z
(ii)
to a minimum. Its length does not exceed 3 m, it is installed in such a mannel as to reduce the risk of fault (see also persons to and it is installed in such a manner as to reduce to a minimum the risk offire or danger Regulation 434.2.1).
433.3
Omission of devices for protection against overload
or risk ofexplosion or This regulation shall not be applied to installations situated in locations plesenting a fire risk conditions' where ihe lequirements for special installations and locations specily different
433.3.1
General
A device for protection against overload need not be provided: (i) for a conductor situated on the load side of the point where a reduction occurs in the value of currentdevice carrying capacity, where the conductor is effectively protected against overload by a protective installed on the supply side of that point
(ii) (iii)
for
a
likely to carry overload conductor which, because ofthe chalacteristics ofthe load or the supply, is not
curTent,plovidedthattheconductoliSplotectedagainstfaultcurrentinaccordancewiththerequirerrrents of Section 434 and aglees that it affolds at the origin ofan installation where the distlibutol plovides an overload device protectioi to the part of the installation between the origin and the main distribution point ofthe installation where further overload protection is provided
433.3.2
Position or omission of devices for protection against overload in lT systems
of devices The provisions in Regulations 433.2.2 arLd 433.3 for an altemative position or omission is overload against protected not for protection against overload are nJt applicable to IT systems unless each circuit protected by one ofthe following means: (i) Use ofthe protective measures described in Regulation 413 2
433.3.2.1
(ii) (iii)
An RCD that will operate immediately on the second fault either: For pennanently superuised systems only, the use of an insulation monitoring device which
(a) causes the disconnection of the circuit when the first fault occurs, or the presence of a fault. The fault shall be corrected in accordance with (b) ' ' gives a signal indicatingand recognition of the consequences of a second fault' iperationai lequirements in tn an IT sysrem without a neutml conductor it is permitted to omit the overload protective device one ofthe line conductors if an RCD is installed in each circuit'
433.3.2,2
433.3.3
Omission of devices for protection against overload for safety reasons
curent-using equipment The omission ofdevices for protection against overload is pemitted for circuits supplying where unexpected disconnection ofthe circuit could cause danger or damage' Examples of such circuits are:
(i) the exciter circuit ofa rotating machine (ii) the supply circuit ofa lifting magnet (iii) the secondary circuit ofa curent tansformet (iv) a circuit supplying a fire extinguishing device (v) a circuit supplying a safety service, such as a fire alarm or a gas alarm (vi) a circuit supplying medical equipment used for life support in specific medical
locations where an IT system
is incotporated.
NOTE: 433.4
In such sitLrations consideration should be given to the provision ofan overload alann'
Overload protection of conductors in parallel
no branch circuits or where a single protective device protects t\ro or more conductols in parallel there shall be
devices for isolation or switching
ir
the parallel conductors.
This regulation does not preclude the use ofring linal circuits with or without spur connecrions.
433.4.1
Equal current sharing between parallel conductors
Except for a ring final circuit, where spurs are pennitted, where a single device protects conductors in parallel and the conductors are sharing cuffents equally, the value ollz to be used in Regulation 433.1.I is the sum ofthe curentcarrying capacities of the parallel conductors.
It is deemed that curent sharirg is equal if the requirements ofthe llrst indent ofRegulation 523.7(i) are satisfied.
433.4.2
Unequal current sharing between parallel conductors
Where the use ofa single conductor is impmctical and the currents in the palallel conductors are unequal, the design cunent and requirements for overload protection fol each conductor shall be considered individually. NOTE: Currents in parallel conductors are considered to be unequal ifthe difference between the curents is lnore than 10 o;
ofthe design cufent fol each conductor Rel'er to paragraph 2 ofAppendix
434
10.
PROTECTION AGAINST FAULT CURRENT
This section only considem the case of a fault between conductors belonging to the sane cicuit.
Determination of prospective fault current
434.1
The prospective fault current shall be detemined at every relevant point of the installation. This shall be done by calculation, measurement or enquiry.
Position of devices for protection against fault current
434.2
A device ploviding protcctiorl against laull cuncnt shall bc installed at the point whcrc a rcductiou ill thc crosssectional area or other change causes a reduction in the culrent-carrying capacity ofthe conductors, except rvhere Regulation 43,1.2.1 . 434.2.2 or 43,1.3 applics. The requirc:rcnts in Rcgulatiorls:t34.2.1 and 434.2.2 shall not be applied to installations situatcd in locatiuns presentiflg a fire risk or risk of explosion or u'heIe speciai requiremerls for ceftain locatiols specify different conditions. 434.2.1 Exccpt $,hcrc Rcgulation 434.2.2 or ri34.3 applies. a device fbr protection against tault curent ma.v be installed other than as specified in Regulation 434.2, under the following conditions: In the paft ofthe conductor between the point ofreduction of cross-sectional area or other change and the position ofthe protective device there shall be no branch circuits or socket-outlets and that part ofthe conductor shall:
(i) (ii)
not exceed 3 m in length, and be instatled in such a manner as to reduce the risk
NOTE:
olfault to a rninimurn, and
This condition may be obtained. for cxan'rple, by reinforcing the protection ofthc wiring against extemal iDfluences.
(iii) be installed in such a manner as to reduce to a minimum the dsk offire or danger to persons. 434.2.2 The device protecting a conductor may be installed on the supply side ofthe point where
a change
occum (in cross-sectional area, urethod of installation, type of cable or colductor, or in envirolmental conditions) provided that it possesses an operating characteristic such that it protects the wiring situated on the load side against fault cunent, ir accordalce with Regulation 434.5.2.
Omission of devices for protection against fault current
434.3
A device for protection against lault curent need not be provided for':
(i) (ii) (iii) (iv)
conductor connectilg a generator. transfonner, rectifier or an accumulator battery to the associated control panel where the protective device is placed in the panel
a
a circuit where disconnection could cause danger for the opemtion of the installation concemed, such as those quoted in Regulation 433.3.3
cetain measuring circuits the origin ofan installation where the distributol installs one ol mole devices providing protection against fault current and agrees that such a device affords protection to the pafi ofthe installation between the origin and the main distribution point ofthe installation where further protection against lault current is provided,
91
provided that both olthe lbllos ing conditions are simulraneousl-t fulfi1led:
(a)
The wiring is carried or.rt in such a rvay as to reduce the risk offault to a minimum (see item (ii) ofRegulation
434.2.1), and
'
(b)
the wifing is installed in such a n.ranner as to reduce to a minimum the risk
434.4
offire or danger to persons.
Fault current protection of conductors in parallel
A single protective device may protect conductors in parallel
against the effects of fault curents provided that the operating characteristic of the device results in its effective operation should a fault occur at the most onerous position in one ofthe parallel conductols. Account shall be taken ofthe sharing ofthe fault currents between the parallel conductors. A fault can be led from both ends ola parallel conductor
lf operation of a single protective device may not be effectiye then one or mole of the following measures shall be taken: (i) The wiring shall be installed in such a manner
as to reduce to a minimum the risk ofa fault in any parallel provision conductor, for example, by the ofplotection against mechanical damage. In addition, conductors shall be installed in such a manner as to reduce to a minimum the risk offire or danger to persons
(ii) For two conductors in paral1el, paral1e1
(iii)
a
fault culrent protective device shall be provided at the supply end ofeach
conductor
Fol rnore than two conductors in parallel, a fault cunent protective device shall be provided at the supply and load ends ofeach parallel conductor
NOTE:
Further infomation is given in paragraph 3 ofAppendix 10.
434.5
Gharacteristics of a fault current protective device
Every fault current protective device shall meet the requirements ofthis regulation.
434.5.1
Except where the following paragraph applies, the rated short-circuit breaking capacity of each
device shall be not Iess than the maximum prospective fault curent at the point at which the device is installed.
A Iower breaking capacity is pemlitted if another protective device or devices having the necessary rated shortcilcuit bleaking capacity is installed on the supply side. ln this situation, the characteristics ofthe devices shall be co-ordinated so that the energy let{kough ofthese devices does not exceed that which can be withstood, without damage, by the device(s) on the load side.
NOTE:
Technical data for the selection ofprotective devices can be requested from the manufactuer
434.5.2 A fault occurring at any point in a circuit shall be intemrpted within a time such that the fault cunent does not cause the pennitted limiting temperature ofany conductor or cable to be exceeded. For a fault of very short duration (less than 0. I sec), for curent limiting devices k2S2 shall be greater than the value ol let-through energy (lrt) quoted for the Class ofprotective device to BS EN 60898-1, BS EN 60898-2 or BS EN 61009- 1, or as quoted by the manufacturer. The time, t, in which a given lault current will raise the live conducton ftom the highest permissible temperature in can, as an approximation, be calculated from the fomula;
nomal duty to the limiting temperatue,
.:-F k2
s2
whele:
92
t
is the duration in seconds
S
is the cross-sectional alea ofconductor in mml
I
effective fault current, in amperes, expressed lor AC curent limiting effect olthe circuit impedances
k
is a factor taking account of the resistivity, temperature coeffrcient and heat capacity of the conductor mate al, and the appropfiate initial and llnal temperatwes. For comnon materials, the values of k are shown in Table 43.l.
is the
as the
rms value, due account being taken ofthe
TABLE 43.1
-
Values of k for common materials, for calculation of the effects of fault current for disconnection times up to 5 seconds Conductor insulation
Thermosetting
Thermoplastic 90
70'c
"c
Conductor
< 300
> 300
< 300
cross-
mml
mm2
mm2
90
'c
60
'c
Mineral insulated Thermoplastic
Bare
sheath
(unsheathed)
> 300 mm2
sectional area
Initial
90
'c
70'c
90
'c
60
'c
70'c
105 "C
160'c
250 "C
temperature
Final Copper
160'C
140'C
160
"c
140'c
250'C
200
"c
k=
k=86
k=
115
k=
k=
k=
141
100
103
143
k=
115
135/ I 15.
conductor
Aluminium
k=66
k=68
k=94
k=93
k=
k=
k=
conductor
Tin soldered joints in
k=
100
k=86
k=
115
103
100
122
copper conductors "
This value shall be used for bare cables exposed to touch.
NOTE
l:
The rated current or curent settillg of the fault curent protective device may be greater than the curent-carrJ irlg capacity of the cable.
NOTE 2: Other values ofk can be determined by reference to BS 7454.
434.5.3 For a busbar trunking system complying with BS EN 61439-6 or a powertrack system complying with BS EN 61534, one ofthe following requirements shall apply: (i)
The mted short-time withstand current (Icw) and the rated peak withstand curent of a busbar trunking system or powedrack system shall be not lower than the rms value ofthe prospective fault curent and the prospective fault peak current value, respectively. The maximum time for which the Icw is defined for the busbar trunking system shall be greater than the maximum operating time ofthe protective device
(ii)
The rated conditional shofi-circuit curent of the busbar tmnking system or powefirack system associated with a specific protective device shall be not lower than the prospective fault curent.
435 435.1
CO.ORDINATION OF OVERLOAD CURRENT AND FAULT CURRENT PROTECTION
Protection afforded by one device
A protective device providing protection against both overload curent and lault current shall fulfil the requirements ofthe relevant regulations in Sections 433 aod 434. Except as required by Regulation 434.4 or 434.5.2, where an overload protective device colrplying with Regulation ,133.1 is to provide lault current protection and has a rated shon-circuit breaking capacity not less than the value of the maximum prospective fault cu-rent at its point of installation, it may be assumed that the requirements of this section are satisfied as regards fault current protection ofthe conducto$ on the load side ofthat point. The validity ofthe assu[.rption shall be checked, where there is doubt, for conductors in parallel and for ceftain types
of circuit-breaker e.g. non-currentJimiting types.
93
435-2
Protection afforded by separate devices
fault The requiremelts ofSections 433 and 434 apply, respectively, to the overload curent plotective device and the culTent protective device.
protective The characteristics ofthe devices shall be co-ordinated so that the energy let through by the fault current (see protective device overload by the device does not exceed that which can be withstood without damage For 60947-4-1 in BS EN specified Regulation 536.J ). This requirement does not exclude the type ofco-ordination hed in desc type of co-ordination precJude the a circuit incotporating a motor stafier, this requirement does not sought. shall be staller ofthe BS EN 60947-4-1, iniespect ofwhich the advice ofthe manufacturer
436
LIMITATION OF OVERCURRENT BY THE CHARACTERISTICS OF THE SUPPLY
they ale supplied liom a Conductors are considered to be protected against overload current and fault current where (e g certain bell source incapable of supplying a curent excieding the current-carrying capacity ofthe conducto$ genemting set)' tansformeri, certain welding transfomels and cerlain types of thermoelectric
94
CHAPTER 44 PROTEGTION AGAINST VOLTAGE DISTURBANCES AND
ELECTROMAGNETIC DISTURBANCES CONTENTS MO
INTRODUCTION
440.1
Scope
440.2
General
441
NOT USED
M2
PROTECTION OF LOW VOLTAGE INSTALLATIONS AGAINST TEMPORARY OVERVOLTAGES DUE TO EARTH FAULTS IN THE HIGH VOLTAGE SYSTEM AND DUE TO FAULTS IN THE LOW VOLTAGE
442.1
Scope and object
442.2
Overvoltages in low voltage (LV) systems during a high voltage (HV) earth fault Power frequency stress voltage in the event of loss of the neutral conductor in TN or TT system
442.3 442.4
Power frequency stress voltage in the event of an earth fault in a lT system with distributed neutral
442.5
Power frequency slress voltage in the event of short-circuit between a line conductor and the neutral conductor
443
PROTECTION AGAINST TRANSIENT OVERVOLTAGES OF ATMOSPHERIC ORIGIN OR DUE TO SW|TCHING
443.1
Scope and object
443.4
Overvoltage control
443.5
Risk assessment method
443.6
Classification of rated impulse voltages (overvoltage categories)
Annex 4443 4443.1
4443.2 4443.3 4443.4
Example 1 - Building in rural environment Example 2 - Building in rural environment supplied by HV Example 3 - Building in urban environmenl supplied by overhead lines Example 4 - Building in urban environment supplied by underground cables
Annex 8443
444 444.1
MEASURES AGAINST ELECTROMAGNETIC DISTURBANCES Scope
444.2
/Vot used
444.3
Nol used
444.4 444.5
Electromagnetic disturbances Earthing and equipotential bonding
444.6
Segregation of circuits
444.6.1
General
444.6.2
Equipment
Annex 4444
(lnformative) l\4easures against electromagnetic disturbances
445
PROTECTION AGAINST UNDERVOLTAGE
445.1
General requirements
95
I
CHAPTER 44 PROTECTION AGAINST VOLTAGE DISTURBANGES
440 440.1
INTRODUCTION
Scope
These requirements are intended to provide for the salety ofelect cal installations in the event ofvoltage disturbances an
and tr;smission for such systems, aithough such distubances may be conducted into or between electrical iNtallations via these supply systems. The requirements of this chapter are in addition to those of Chapter 43'
General
440.2
Thjs chapter covers the protection of electrical installations and measures against voltage disturbances
and
electromignetic disturbances. The requirements are aranged into four sections as follows:
(1)
Sectiou 442
Protection of low voltage installations against temporary overvoltages dtte to eafth faults in the high voltage system and due to faults in the [o]" voltage system
(ii) (iii) (iv)
Section 443
Protection against overvoltages of atmospheric origin or due to switching
Section 444
Measures against electromagnetic disturbances
Section 445
Protection against undewoltage.
441 442
NOT USED PROTECTION OF LOW VOLTAGE INSTALLATIONS AGAINST TEMPORARY
oVERVoLTAGESDUEToEARTHFAULTSINTHEHIGHVoLTAGESYSTEMANDDUE TO FAULTS IN THE LOW VOLTAGE
Scope and oblect
442.1
This regulation provides requirements fol the safety ofthe low voltage installation in the event of: (i) a fault between the high voltage systelr and Earth in the transformer substation that supplies the low voltage installation
(ii) (iii) (iv)
loss ofthe supply neutral in the low voltage system
shoft-circuit between a line conductor and neutral in the low voltage installation accidental eafthing ofa line conductor ofa low voltage IT system.
NOTE:
in The requirements for the eafthing oftransformers that provide a supply frorn a system for distribution of electricity in the Distribution addressed (ESQCR) are Regulations accordance with the Electricity safety. Qua!i1y and cortinuity Code.
442.'l
.'l
General
Section 442 gives rules for the designer and installer of the substatior. information on the high voltage system:
(i) (ii) (iii)
It is necessary to
haYe the following
Quality ofthe system eafthing Maximum level of earth fault current Resistance
ofthe eafihing arrangement.
overvoltages: The following regulations consider four situations which generally cause the most sevele temporary (iv) Fault betweer the high voltage system(s) and Eafih (see Regulation 442 2)
(v) Loss ofthe neutral in a low voltage system (see Regulation 442 3) (vi) Accidental earthing ofa low voltage IT system (see Regulation 442 4) (vii) Shoft-circuit in the Iow voltage installation (see Regulation 442 5)'
Symbols
442.1.2
in Sectioi 442 the lollowing symbols
are used (see Figure 44.1):
IE
pafi ofthe earth fault curent in the high voltage system that flows through the eafihing an angement of the transformel substation
R!
resistance ofthe earthing arangement ofthe transfomer substation
RA
resistance ofthe earthing affangement ofthe exposed-conductive-parts ofthe equipment ofthe low voltage
RB
resistance of the eafihing arrangement of the Iow voltage system neutral, for low voltage systems in which the eafihing arangements olthe tansfomer substation and ofthe low voltage system neutral are electrically independent
uo
in TN and TT systems: nominal AC rms lire voltage to Earth
I
in IT systems: nominal AC rms voltage between line conductor and neutlal conductor or midpoint
I
installation
conductor, as approp ate
Uf
power frequency fault voltage that appears in the low voltage system between exposed-conductive-parts and Earth for the duration ofthe fault
ur
power frequency stress voltage between the line conductor and the exposed-conductive-parts of the low voltage equipment ofthe translormer substation dudng the fault
U,
power frequency stress voltage between the line conductor and the exposed-conductive-parts of the equipment ofthe low voltage installation during the fault.
NOTE 1: Ihe poq,er liequency stress voltages (U1 and U2) are the voltages that appear across the insulation of Iou voltage equipmcnt and across sur€e protective devices connected to the low voltage systc[r.
The following additional symbols are used in respect of IT systems in which the exposed-conductive-pafts of the cquipment ofthe low voltage installation are conncctecl to an earthing arangenlent that is elect cally independent ofthe eafihilg arangcnlcnt ofthe translbtmer substation.
the fault curent that flows through the earthing arangement of the exposed-conductive-pafis of the equipment ofthe low voltage installation during a period when there is a high voltage fault and a flrst fault in the low voltage installation (see Table 44.1)
Id
the fault cun'ellt, itr accordancc with Regulation 411.6.2, that florvs through thc carlhing afiangement of the exposcd-conductive-pafis of the low voltagc installation duri[g the fint fault i[ a low voltage system (see Table 44.1) is the impedance (for example, the IMD intemal impedance or the artificial neuftal impedance) between the low voltage system and an earlhing arrangement.
NOTE 2: An earthing anangement may be considered electrically independent of another earthing arangement if a rise of potential with respect to Earth in one earthing anangement does not cause an unacceptable se of potential with respect to Eafih in the other eadhing arangemcnt.
Overvoltages in low voltage (LV) systems during a high voltage (HV) earth fault
442.2
In
case of a fault
to Eath in the HV side of the substation the following types ol overvoltage may affect the LV
installation:
(i) (ii)
Power frequency fault voltage (Ur) Power fiequency stress voltages (Ur and U,).
Table 44.1 provides the relevant methods ofcalculation for the different types olovervoltage.
,r'""\ ,f,,
**" ": 97
diagram for connections to Earth in the substation I - Representative ' '-'ii"t"ttrtion occurring in case of faults
Fiq I '!' 44.1 --i
ana irte
and the LV
o'"*ottages
LV lnstallation
Substation
--?I I
.-.-..?.-
-------a ., [lH *u
I I
I
I I
I
I
U1
I
il*^ I
I
I I
-!-
_l
practices are presently used: exist in proxirnity to each othel two Where high and low voltage eafthing systems
-intelconnectionofallhighvoltage(Ru)andlowvoltage(RB)eafihingSyStemS -separationofhighvoltage(R,)fromlowvoltage(R,)earthingsysteruS. shall be interconnected The high and low voltage eafthing systems The peneral method used is interconoection by the high voltage earthing svstem (see ,,i,rririirr"
ila:ffi ffi;:r.i"*-i
i"i"[v'i""ir"a
"r., "or"r"d
BS EN 50522). are showr in Part r,(rdrLjriLofthe difftrent types of systern eafthing l Details NOTE 1: NLtIE
ut t rnslbnncrslhatpro'"": NOTE 2: Thc requirements lbrthc carthrDg
Ii"',:::'::'ff'Til5T:;ffi:il;;
A;;,;;;""i1"",*,nv
I
(TN' TT) and Appendix 9 (lT)
*"1'l-fi::':::::::::::T::::::l;:H[Xil';
n"e,iaiions (ESQCR)
are addressed in the DistributioD
Code.
Hore s,
o"t"1"l"li:-:l:t1;1 i;;N 50522, rable 2. gives rninin'tun requirements l" ::::.:::':Y:j: i::il:X"Til[: l"'',i) iliii;'ll',i"i.ll',ii',, """.*;"* o*''o'u', " '.:'i:t:1^:1,:i:,::l:l;i T,';;lT,'I"",'1"*'" vortage). ;:.":T,iT':1,'I,il:lt;:ffi.;;';i;;., "*.,",.Lr* eanh potenriarrise'(EpR-srress TABLE 44.1 - Power frequency stress voltages low voltage system and power frequency fault voltage in the of earth connections
Type of system
earthing
TT TN
uo
RrixlE+ Uo
0r'!
Ru and Ru seParated
REXIE + Uo
Uu*
0-
R. and Rn connected
uo
Un*
Rr* [r +*
R, ard R, seParated
REIE+Ulr
Tt :!-
uo
REXIE + Uo
0x 0x
Un"!3
Rurlr + Un"\i3
Ro'In
uo
u,,
REXIE
Uo'i3
Un'!3
&*I.
RrxIE + Uo
Uo*
0*
-Type R. and R" cotnected
Ru
and Z connected
RE and
R.
separated
t
R,, and Z connected
tT
uf
U,
ur
R.
ancl Ro interconnected
R,
aud Z seParated
R. and R^ seParated
I
Un'i3
t
fault in the installation'
*
I
R^'Io
-;tu+uu,13
"*irtirg "u.thneed be given
* No consideration
**
See
Regulation 442.2
1
equipment with regard A".ign criteria for insulation of low voltage (see also Table '14 2)' to temporary powei frequenc.v oven'oltage
-with NOTE 1: The requirements for.lJ,
98
una
Uffifio,r,
NOTE 2: In a system whose neutral is connected to the earthing arrangemcnt of the transforoer substation, such temporar'y powel frequency overvoliage is also to be expected across insulation which is not ill an earthed enclos re where the equipment is outside a building. NOTE 3: ln TT and TN systems the terms 'cotnected' and 'separated' refer to the electrical connection between R, and R". For IT systems the telms refer to the electrical connection between RE and Z and the connection between RE and R..
442,2.1
Power frequency fault voltage
The fault voltage U1 as calculated in Table 44.1, which appears in the low voltage installation between exposedcondllctive-parts and Eafih, shall not exceed a dangerous level. NOTE
l: In a TN system
whcre RE al1d RB are connected together (see Table 44.l), their connectiorl to a ]ow voltage global earlhing systern as described in BS EN 50522:2010, clause 3.4.19, can be considered to be a safety lneasure against dangerous 1'ault vo)tages.
NOTE 2: A global earthing system is an eafthing system created by thc intcrconnection oflocal eafthing systems that provides. by the proximity ofthese eafthiDg systens. that there are no dangerous touch voltages.
In installations outside a global earthing system, additional connection shall be made between the PEN conductor and Earth.
442.2.2
Magnitude and duration of power frequency stress voltages
The magnitude and dumtion ofthe power frequency stress voltages (U1 and U2), where specified in Table 44.1, on the equipment in the low voltage installation due to an eath fault in the high vottage system, shall not exceed the requirements given in Table 44.2.
TABLE 44.2
-
Permissible power frequency stress voltage
Duration ofthe earth lault in the high voltage system t
Permissible power frequency stress voltage on equipment
>5s
in low voltage installations U
Uo+250V Uo + 1200 V
l5s In systems without a neutral conductor, Uo shall be the line-toJine voltage.
NOTE
1
: Tbe lirst line of the table relates to high voltage systems haviug long disconnection tirnes, for example, isolated neutral and resonant earthed high voltage systems. Thc second line relates to high voltage systems having short disconnectior times, for example. low-impedance earlhed high voltage systems. Both lines together are relevant design criteria for insulation of low voltage equipncnt with regard to temporary power frequency overvoltage, BS EN 60664-1.
NOTE 2: In
a systern whose neutral is connected to the earthing atangement ofthe tmnsformer substation, such temporary power frequency overvoltagc is also to be expected across insulation which is not in an earthed erclosure where the cquipLnent is outside a building.
442.2.3
Requirements for calculation of limits
The requirements ofRegulations 442.2 .l and 442.2.2 are deemed to be fulfilled for installations receiving a supply at low voltage from a system for distdbution of electricity to the public.
fulfil the aboverequirements co-ordirlation betweenthe HV system operatorandthe LV system iostalleris necessary. Compliance with the above requirements trainly falls into the responsibility of the substation installer/ownei operator who needs also to fulfil requirements provided by BS EN 61936- 1. Therefore, the calculation for U,. U. and Ul is nonnally not necessary for the LV system installer. To
Possible measures to fu1fi1 the above lequirements are, for example:
(i) (ii) (iii) 442.3
separation of HV and LV earthing arangerrents change
ofLV system earlhing
reduction ofearth resistance,
RE.
Power frequency stress voltage in the event of loss of the neutral conductor in TN or TT system
Consideration shall be given to the lact that, ifthe neutral conductor in a thrce-phase TN or TT system is intemrpted, basic, double and reinforced insulation as well as cornponents mted for the voltage between line a1ld neutral conductors call be temporarily stressed with the ]ine-toline voltage. The stress voltage can reach up to U : {3 U0.
of .. Power frequency stress voltage in the-event neutral distributed with t"lft i, lT system
442.4
i
"" ""tttt
Considerationshallbegiventothefactthat,ifalineconductorofanlTSvstemisearthedaccidentally,insulationor the [ine-toii* urd n"rt ul "orductors can be temporarily stressed with components rated for tlr. ,ottug. u.il""n
i#;;i;;.
ih"
uo uress voltage can reach up to U = ri3
event of Power frequency stress voltage in the a line conductor and the neutral conductor
442.5
$;-"i;;iii;;i*een
a line
voltage installation between that, if a Sbofi-circuit occurs in the low Consideration shall be given to the fact and the neutral conductor can conductors u"*a-, trre other line conductor and the n"unul "oraua,o.],'ha^""1"ga lor a time up to 5s' L, reach the value of 1
45
PROTECTION AGAINST TRANSIENT OR DUE TO SWITCHING
443
ORIGIN OVERVOLTAGES OF ATMOSPHERIC
Scope and object
443.1
This section deals with protection of electrical.install"i"lt
443.1.',|
arllros*rErr! urrExL
uq!,"!-"-- -'
',Ci.lT:^^tl1':1"-t:.::::"::::-:',:j ro rhe suppr) s)slem and
within the installation' "#l;l'1fi'.Tl;;J;id;,,:Jil;tir::i'*::::,*',','"'i'"'o" uy ttt" gene "quipment
"of.'"1;'1.,,. against switching overvoltages
'utto due to direct or nearbY for protection against tmnsient overvoltages requirements specify This section does not lightning strokes on the structure' NoTEI:Forriskmanagementtbrprctectionagainsttransientover'voltagesduetodirectornearbylightningstrokesonthe structure, see BS EN 62305-2'
cover lngeneral.sr.ritchingo\ervoltageshaveloweramplitudetJrantransientovervoltagesofaimosphericoriginand o'"tuoltaget of atmospheric origin normally
;;;;"il;;"i"nt therefore the requir"."nt, ,"gu'atng: protection against switching overvoltages'
i
If
I
against of atmosphedc origin is installed' protection no transient ovewoltage protection against disturbances
provided' switching overvoltages may need to be
I
NoTE2:overvoltagesduetoswitchingcanbelongelindurationandcancontainmoleenergythantransientovervoltagesof atmospheric origin (see Regulation 443'4)'
NOTE
NOTE
3:
-
4:
;; ,;;,;."
i I
downstream in distribution system are not significantly attenuated Transient overvoltages transmitted by the supply most installations'
I
(ICT) Control and Telecommunications
I
This section does not cover overvoltages ,ystem,.
I
as: ofatmospheric origin depend on factors such The characteistics oftraDsient overvoltages (underground or overhead) the nature ofthe supply distribution system device (SPD) upstream of the installation protective ;".*e the possible exisren"" the voltage level ofthe supply system'
i;;;iEN
sotz+,
ss
o-lTf:{-b]
I
-IiPrmation' EN 623-0s-4 and BS EN 61643-22'
NOTE5:Asregardstansjentoveoltagesofatmosphericorigin'nodistinctionismadebetweenearthedandunearthed
I
systems.
whereplotectionagaiustovefloltagesiSbytheuseofSurgepfotectivedevices(SPDs)theyshallbeselectedand erected in accordance with Section 534' Table 443 2' vaious rated impulse voltages arc given in NOTE 6: Examples of equipment with I ofTable 443 2' have protection levels lower than Category NOTE 7: Some electonic equipment may are: where the consequences of overvoltage This section does not apply to installations
(a)
exPloiion
(b1
chemical or radioactir e emis'ions
NOTE8:
BS EN 62305-2 applies for such
I I
I I
I
I
I
high
I
sk installations' I
I
443.2
Not used
443.3
Not used
I
443.4
Overvoltage control
Protection against transient overvoltages shall be provided where the consequence caused by ovewoltage could:
(i) (ii) (iii) (iv)
result in serious injury to, or loss of, human life, or result in intemrption ofpublic sewices and/or damage to cultural heritage, or result in interuption of commercial or industrial activity, or affect a large number ofco-located individuals.
For all other cases, a risk assessment according to Regulation 443.5 shall be performed in order to determine if protection againsttansient overvoltages is required. Ifthe risk assessment is notpeformed. the electrical installation shall be provided with protection against tmnsient overvoltages, except for single dwelling units where the total value ofthe installation and equipment therein does notjustily such protection. Protection against switching overvoltages shall be considered in the case of equipment likely to produce switching overvoltages or disturbances exceeding the values according to the overvoltage category of the installation, e.g. where an LV generator supplies the installation or where inductive or capacitive loads (e.g. motors, transfomers, capacitor banks), storage units or high-curent loads are installed.
443.5
Risk assessment method
Calculated risk level (CRL) is used to detemine ifprotection against tansient overvoltages of atmospheric origin is required. The CRL is found by the following formula:
CRL :i",/(LpxNg)
f"", Ln Ne
is an environmental factor selected according to Table 443.1 is the dsk assessment length in km (see below) is the lightning ground flash density (flashes per km'?per year) relevant to the location ofthe power line and connected structure (see Figure 44.2).
'1
01
-e
Figure 44.2
-
Flash density map of UK
g"
F
F* "B
-t_
&,
#*
LIGHTNING
FLASH DENSITY Ng (flashes/km'z/year) KEY
!
Use 0.1 Ng
I
Use 0.3 /vs
!
. I
=
:=
4"{}=
iliili
Use 0.5 Ng Use 0.8 lvg Use t .o /vs
[iii$ use r.z rvs
!
Use 1 .a Ng max
r_E
1
) fu,''*; I L.+.f
E.tri *.
=e
-lr-r
Jffi-G&
r
,i
o^
I
Table 443.1
-
Calculation of f"",
Environment
f.,,,
Rural and suburban environment
85
Urban el]Yircrlment
850
The risk assessment length Lp is calculated as follows:
Lf
:2
L1AL
+ LfcL + 0.4 Lp",1+ 0.2
Lp6H
(krrr)
where:
oflow voltage overhead line is the length (km) oflow voltage underground cable is the length (km) ofhigh voltage overhead line is the length (km) ofhigh voltage underground cable. is the length (km)
Lrot
L".. Loo,t
Lr.,
The total length (LpaL + Lrc! + L|AH + Lp(.H) is limited to 1 km, or by the distance ftom the first overvoltage protective device installed in the power network to the origin ofthe electdcal installation, whichever is the lesser
If the dist bution network lengths are totally or pafially unknown then Lpor shall be taken as equal to the remaining distance to reach a total length of I km. For example, if only the distance of underground cable is known (e.g. 100 m), the Lp11 shall be taken as equal to 900 m. An illustration of an installatiol1 showing the lengths to consider is given in Figure 44.3. Figure 44.3
-
lllustration showing the lengths to consider for the calculation of Lp This arrangement
isfor illustrative purposes only
Lo.,
1,,,
Key
1 2 3
sulge arestor (overuoltage protective device) on the overhead HV system
HV/LV fansformer origin ofthe electrical installation
If CRL > I 000, protection against tarsient overuoltages ofatmospheric origin is not required. If CRL < I 000, plotection against tmnsient overvoltages ofatmospheric origin
NOTE:
Examples ofcalculations
443.6 443.6.1
is required.
ofCRL ale given inAnnex A443.
Classification of rated impulse voltages (overvoltage categories) Purpose of classification of rated impulse voltages (overvoltage categories)
Overuoltage catego es are defined within electrical installations lor the purpose of insulation coordination and related classification ofequipment with rated impulse voitages is provided (see Table 443.2). The rated impulse voltage is used to classify equipment energized directly fi'on.r the low voltage electrical installation
into overvoltage categories.
l-^
103
voltage ale provided to distinguish diffet ent Rated impulse voltages for equipment selected according to the nominal an acceptable risk offailure and levels ofavailability ofequipment with regard to continuity ofservice rated inpulse voltage ofthe equiprnent Inherent oveNoltage control for insulation coordination, based only on the in accordance with BS EN 60664-1, is not sumcient lvhere:
-transieltovervoltagestmnsmittedviathesupplydistr.ibutionsystemalenotSignificantlyattehllated downstream
NoTE:Insulationcoordioaiioncanbeachievedinthewholeinstallationbytransientovervo]tageprotectiolrofthe
reducing the risk of failure to an eqLlipment colTesponding to the classi6ed mted impulse voltagc' thereby accePtable level.
-
surge curents and pafiiat
lightnilg curents
are distributed via underground cables
equipment is connected to multiple services, e
g power, telecol'nmunications
and data lines'
(see BS EN 60664-1) of the most sensitive equipmert to ofequipment is u[acceptable, the impulse be protected in the systeur or., in cases where a te,rf,orary loss offunction immunity voltage (see BS EN 61000-4-5).
It is necessary to consider the rated ilrpulse voltage uw
443.6,2
Rated impulse voltages of equipment and overvoltage categories
installation, for equipment is suitable for use at, or in the proximity of, the origin of the electlical withstand iu]pulse high a very has IV category of Equipment uprtreum of the main distribution board than the not less voltage impulse rated "rafpte, have a shall and capability providing the required high degree of retiabiliiy, value specified in Table 443.2.
category
Iv
ofand including the main distribution Category III equip[rent is suitable for use in the fixed installatior downstream not less than the value specified voltage impulse a rated have shall and t oari, proriaing u 1,igh degree ofavailability. in Table 443.2.
ofavailability normally the value specified in fo, curient_using equipment, and shall have a rated impulse voltage not less than
categoly Il equipment is suitable for connection to the fixed installation, providing
,.qui.d
a degree
Table 443.2. SPDs are installed outside the equipment Category I equip[rent is only suitable fot use in the lixed installation where voltage not less than the value to liriit transient over-voltaaes to the specified level, an<1 shall have a rated impulse voltage corespondirg to overvoltage category specified in Table 443.2. Therefore, equipment with a rated impulse I should, pret'erably, not be instalted at or near the origin ofthe installation'
104
lable Nominal voltage ofthe installation
443,2
-
Required rated impulse voltage of equipment (Uw)
Voltage line to
Required rated impulse voltage ofequipmentb kV
ne[tral derived from nominal voltages AC or DC up to and including V Overvoltage
Overvoltage
category IV (equipment with very high rated impulse voltage)
category
Overuoltage category II (equipment with normal rated impulse voltage)
III
(equipment with high rated impulse voltage)
Overvoltage category I (equipment with reduced mted impulse
voltage) For example, energy meter,
For example, dist bution
For example,
telecontrol
boards, switches socket-outlets
appliances, tools
systems
dome stic
For example, sensitive
electronic equipment such as
alarm panels, computers and home electronics 120/208
150
1
2.5
1.5
0.8
230/400.
300
6
4
2.5
1.5
400/690
600
8
6
4
2.5
I000
1000
12
8
6
4
1500 DC
I
277/480
a b c
500 DC
According to BS EN 60038:2009. This rated impulse voltage is applied between live conductors and PE.
For IT systems operating at 220-240 y, the 230/400 row should be used, due to the voltage to earth at the earth fault on one line.
ANNEX A443 (lnformative) EXAMPLES OF CALCULATED RISK LEVEL CRL FOR THE USE OF SPDs
4443.'l
Example
1
-
Building in rural environment
Ground flash density
N"
Envilonmental factor
f.,,.
Risk assessment length Lp = 2
LPAL
+ Lp(.I + 0.4 Lplu
:85
t
0.2 Lpcrr
:
(2 x 0.4) + (0.4 x 0.6)
=
1.04
where:
CRf
Lrr.
is the length (km) of low voltage overhead line
-
Lrnn
is thc length (km) ofhigh voltage overhead line
= 0.6
Ln.,
is the length (km)
oflow voltage underground cable
=0
Lo.,
is the length (km) ofhigh voltage urrderground cable
=0
:
f.,,,
/(L,, x 5.1
0.4
:85/(1.04 x 1) = 8t.7
105
as the CRL is less than In this case, SPD protection shall be installed
1
000'
supplied by HV Example 2 - Building in rural environment
A443,2
densitY Environrnental factor
Ground flash
Risk assessment length LP = 2
LPAL
Nt
= 0.3
f.,
=85
+ LPcr * 0 4 Lmrr
*
0 2 Lpctr
=02x1 =02
where:
=0
oflow voltage overhead line
Loo,
is the length (km)
Lpaq
L..,
line is the length (km) ofhigh voltage overhead cable is the length (km) of low voltage underground
Lp6g
cable is the length (km) ofhigh voltage underground
=0 =0
CRL=i,,"/(LpxNJ =85/(02x03) =|4167 as the CRL is greater than In this case, SPD protection is not a requirement
I 000'
A443.3Example3-BuildinginurbanenvironmentSuppliedbyoverheadlines Ground flash densitY
Ns
Environmental factor
f"".
Risk assessment Iength Lp = 2 Lr"rL + Lx:r
= 850
*
0 4 Lp'n + 0 2 LpcrI
=(2x0.4)+(0.4x06) =104 rvlrere:
length (km) oflow voltage overhead llne
= 0.4
length (km) ofhigh voltage overhead line cable is the length (km) of low voltage underground cable is the length (km) ofhigh voltage underground
= 0.6
Lt^,
is the
L,.r,
is the
Lo., Lpcn
CRL = f"." / (LP x
Nr)
= 850 / (1 04
x
=0 =0
1)
= 817 as the CRL is less than 1 000' In this case, SPD protection shall be installed
A443.4Example4-BuildinginurbanenvironmentSuppliedbyundergroundcables
density Environmental factor
Ground flash
Risk assessment length Lr = 2
Nt
= 0.5
f".'
= 850
Lpl + LpcL + 0 4 LPAH + 0 2 LPCH
-1
where:
LrcL.
length (km) oflow voltage overhead line line is the length (km) ofhigh voltage overhead cable is the length (km) oflow voltage underground
Lrc,
is the length (km)
Lo-r, Lon,
is the
CRL=i,,/
(LP
x
N")
ofhigh voltage underground
cable
=0 =0 =0
= 8s0/ (1 x 0's)
=1700 as the CRL is grcater than I 000' In ti'ris case. SPD protection is not a Iecluitemcnt
ANNEX 8443 (lnformative) GUIDANCE ON OVERVOLTAGE CONTROL BY SPDs APPLIED TO OVERHEAD LINES Where an installation is supplied by, or includes, an overhead line and SPDs are required according to Regulation 443.4, the protective control of the overr,,oltage level may be obtained either by installing surge protective devices directly in the installation close to the origir ofthe installation or, with the consert ofthe network operator, in the overhead lines ofthe supply distribution network.
As an example, the following measures may be applied: (a)
in the case ofoverhead supply distribution networks, overvoltage protection is erected at network junction poilts and especially at the end of each feeder longer than 0.5 km. Surge protective devices should be erccted at every 0.5 knr distance along the supply distribution lines. Nevertheless, the distance between surge protective devices should in no case exceed I km
(b)
if
a supply distribution network is erected partly as an overhead network and partly as an underground retwork, overvoltage protection in the overhead lines should be applied in accordance with (a) at each transition point from an overhead line to an underground cable
(c)
in a TN distribution network supplying elect cal installations, where the protective measurc automatic discomection ofsupply is applied, the eafthing conductors olthe surge protective devices connected to the line conductors are connected to the PEN conductor or to the PE conductor
(d)
in a TT distribution uetwork supplying electrical installations, where the protective measure automatic disconnection ofsupply is applied, surge protective devices are provided for the line conductors and for the neutral conductor. At the place where the neutml conductor ofthe supply network is effectively earthed, a surge protective device for the neutral conductor is not necessaxy.
444
MEASURES AGAINST ELECTROMAGNETIC DISTURBANCES
444,1
Scope
This section provides basic requirements and recommendations to enable the avoidance and reduction of electromagnetic disturbances. Those involved in the design, installation and maintenance of, and alterations to, electrical installations shall give due consideration to the measures described in this section.
Electromagnetic disturbances can disturb or damage infomation technology systems or information technology equipment as well as equipment with electronic components or circuits. Currents due to lightning, switching operations, short-circuits and other electromagnetic phenomena might cause overvoltages and electromagnetic interference. These effects are potentially more severe:
(i) (ii)
where large metal loops exist
where different electrical wiring systems are installed in common routes, e.g. for power supply and for signalling and/or data communication cables connecting information technology equipment within a building.
The value ofthe iuduced voltage depends on the mte ofchange (dl/dt) ofthe interference curent and on the size the loop.
of
Power cables carrying large currents with a high rate ofchange of current (dl/dt) (e.g. the stafiing current oflifts or curents controlled by rectifiers) can induce overvoltages in cables of information technology systems, which can influence or damage infomation technology equipment or similar electrical equipment.
In or near tooms for medical use, electromagnetic disturbances associated with electrical installations can interfere with medical electrical equipment. The requirements and recommendations given in this section can have an influence on the overall design of the
building including its structural aspects. The requirements ofthe following standards shall be applied where appropriate;
(iii)
BS 6701: Telecommunications equipmert and telecommunications cabling. Specification for installation,
(iv)
BS EN 50310: Application of equipotential bonding and earthing in buildings with information technology
operation and maintenance
equipment J
107
installation
(v) BS EN 50174 series: lnformation technology Cabling (EMC) (vi) BS lEC 61000-5-2: El""o"-;;;;;t'ltto't"
Eatthing Instaltation and mitisation guidelines
and cabling.
444.2
AIot used
444.3
I\tot used
444.4
Electromagnetic disturbances
444.4.'l
Sourcesofelectromagneticdisturbances
relative to the positioning electromagneti c disturbances to the location ofthe sources of given be shall typically include: consideration oirturbances within an installation potential sources l? eqdpment. other
"i""t "."gr"ti. (i) switching devices for inductive loads (ii) electric motors (iii) fluorescentlighting (iv) welding machines (v) rectifiers (vi) choPPers (VSDs) including Variable Speed Drives t"iil f..o**, *nvertors/rcgulators (viii) lifts (ix) transfotmers (x) switchgear
of
1ri.1 Puwer distribution busbars' the BS EN 50i74 NOTE: For fr'rrther informatio[ refer to 444.4.2 Measures to reduce EMI
444.4.2.1
series ofstandards'
the effects wherc appropriate' in order to reduce considered' be shall measures The following
*?ITil:::::::ffli!"u
of
power be taken to limit the fault curentliom o, au,u.uur"s are used, care should
cy5lemsflowinglhr"'gnt;""';;;;cJresolsignat^cautt''o'ouiutuurtt'*hichareeanhedAddirional seeFigure44 4 conductor for screen reinforcement' conducton may be necessary e g a bypass to provide a common equipotential s*Tffiill":i:t"Jt for conductor Bvpass 44.4 Fis -
Bypass conductor for screen relnforcement
(ii)
with regard to to improve electromagnetic compatibility filteN and/or devices protective The use of surge
;.;"':;ffi ;;d*; ;,;;ag,',"ti" p'eno^elX1ii.ffi :111::::rT:.f:::;HilH[:i, and any protectlve of power cables (i e tine' neutral e
(iii) th" inrtuttutioo (iv) (v)
areas order to minimize cable looP cables signal The separation ofpower and
,i" ,n.o,ru,., "i,n
444.4.3
see Regulation 444 5 2' equipotential bonding network'
TN sYstem
be met' the following requirements shall To minimize electromagnetic distubances' of the installation' be used downsteam of the origin 444.4.3.1 A PEN conductor shall not the Regulations (ESQCR) prohibits Safety' Quality and Coltinuity Regulation 8(4) of the Electricity
NOTE:
conductors in consumers' installations.
Lrse
of
PEN
444.4.3,2 The installation installation; see Figue 44.5.
shal1
have separate neutral and protective conducrors downstream ofthe origin ofthe
Fig 44.5 - Avoidance of neutrar conductor currents in a bonded structure by using an installation forming part of a T.N-c-s system from the origin of the pubric suppty upio ana including the final circuit within a building Bonding conductor, if necessary, see Annex A444.2
PE, N, L
Equipment I
Signal or data cable PE, N, L
Public supply
,.
Key
:
I Loops of limited area formed by signal or data cables.
444.4.3.3 an installation
,:\
Where the complete low voltage installation including the transformer is operated only by the usel sha1l be installed; see Figure 44.6.
foming part ofa TN-S system
l
109
structure by using an installation - Avoidance of neutral conductor currents in a bonded private supply transformer toiming part of a TN-S syste.m downstream of a consumer's
'-
Fig ' 44,6
Key
:
Loops of Iimited area formed by signal or data cables' may be rnade at the tmnsfolmer or the main LV switchgear' point ofn"otl.ut Z
i
it.
444.4.4
"arthing
TT system
InaninstallationfomingpartofaTTsystem,suchaSthatshowninFigure44.T,consideration.shallbegiven where the extraneousio or"rrottugaa wrrich mlght exist between live parts and extraneous-conductive-parts electrodes' eafih .-orOr.tiu. p"u.t, of differeit buildings are connected to different shall be considered' The use of an isolating transfomer to provide a TN-S system
Fig 44.7
-
lnstallation forming part of a TT system within a building installation
Bonding conductor, if necessary, see Annex 4444.2
PE, N, L
Equipment
1
Signal or data cable PE, N, L
Key 1
::
l
:
Loops of limited area formed by signal or data cables.
Where screened signal cables or data cables are comrnon to several buildings supplied from an installation forming part of a TT systen, the use of a bypass bonding conductor (see Figure 44.8) or single-point bonding shall be considered. The bypass conductor shall have a minimum cross-sectional afea of l6 mrn] copper or equivalent, the equivalent cross-sectional area being selected in accordance with Regulation 544.1. Where the live conductorc ofthe supply into any ofthe buildings exceed 35 mmr in cross-sectional area the bypass conductor shall have a minimum cross-sectional area in accordance with Table 54.8.
111
Fig 44.8
-
part conductor in an installation forming Example of a substitute or bypasstonding of a TT system
L1
L2 L3 N
+ Screened slgna cable
cannot be obtained' 4I 1.3.1.2 (telecommunication cables) accolding to the tast palagmph of Regolation ofthose cables exclusion the t"U'" to avoid any danger due to it is the rcsponsibility of tt.tt o*n"' "?t* bonding' irotrr-ifr" .onn".,io, to the nain equipotential
Il conset
#ll"*i*
444.4.5 444.4.6
Not used
Multiple-source TN or TT power supplies
shall be earthed at one point only' supplies to an installation' the system For TN or TT multiple-source power point througb the protective conductor' a single F^r , TN svstem. to avoid having the Deutral curent flowing 44'9' shall be made as iltusffaled in figure
"."*.tion'onfv Fig 44.9
-
of
earth single connection between PEN and TN multiple-source power supply with
i(-
sou.""
r
)i(-
lnstallation
----->i<-sout"" z)i
,I
I
). -^Yi-
i I
I I
illlrl
ri
Exposed_conductive-Parts
NorE
,l
flow applied. nctttral conductor cunents lnight star points of tl.le sourc€s ofsupply,is the of earthing rnultiple where : as shown rn but also via the protective conductor th" n"ut,ut back to rhe relevant sr", 0",.;, ;;J"l;-;; "ondu"ro.. is no longer zero and a stray ti"''*l of the partial currents flowing in the instailation Figule 44 10 fot '}ti""u'on similar to that of a single conductor cable -lgnetic fleld is created,
NoTE2:lnthecaseofasingleconductorcablecalryingACcurrent,acirculalelectromagneticfieldiSgeneratedaloundthe conductorthatmightintert.erewithelectronicequipment.Hanrrouiccurrentsptodtrcesimilarelectromagneticfields cufient' those produced by the fundamental
tui,i",
un"n'u*
t]1ore rapidly tharl
6\ o' cn
Fig 44.'t0
-
TN multiple-source power supply with unsuitable multiple connection between pEN and earth
l*sou'""
I
!l
)lg-
lnstallation
------)l+Sorr"" z9i I
I
I
I
I
connection
444.4.7
Transfer of supply
In an installation foming part ofa TN system the transfer ftom one supply to an altemative supply shall be by means of a multipole switching device which switches the line conductors and the neutral conductor, ifany.
NOTE:
This rnethod prevelts electromagnetic fields due to stray cu[ents in the main suppiy system ofan instal]ation.
444.4.8 Not used 444.4.5 Separatebuildings Where different buildings have separate equipotential bonding systems, metal-ftee optical fibre cables or other nonconducting systems are prefeffed for signal and data translrission, e.g. microwave signal transfonner for isolation in accordance with BS EN 61558-2-1. 2-1.2-6.2-15 and either BS EN 60950- I or BS EN 62368- 1.
444.4.10 lnsidebuildings Within a building, the requirements and recommendations of the following standards shall be applied for control, signalling and cornmuntcalion circuils:
(D
BS EN 50174-1: Infonnation technology Cabling installation: Installation specification and quality assulance
(iil
BS EN 50174-2: Infonr.ntion technology Cabling installation: lnstallation planning and practices inside buildings
(iii)
BS EN 50310: Application ofequipotential bonding and earthing in buildings with information technology equipment.
444.5
Earthing and equipotential bonding
444.5.1
lnterconnection of earth electrodes
444.5.1.1 Within
a single building
All protective ard functional eathing conductors ol an installation within a building shall be connected to the main earthing terminal, as required by Regulation 542.4.1, except where this is precluded by the requirements of legislation or Part 7.
444.5.1.2 Betweenbuildings For communication and data exchange between several buildings, the requirements ofRegulation 542.1.3.3 apply to both the protective and functional earthing requirements.
NOTE:
Where interconnection of the eafih electrodes is not possible or practicable. it is recontmended that separation of cornmunications networks is applied, for example, by using optical or mdio links.
'1
13
444,5.2
Equipotentialbondingnetworks
for the installation: The structure selected for these conductors shall be appropriate
(i)Metalsheaths,Scleensoranrrouringofcablesshallbebondedtothecommonbondingnetwork(CBN) unless such bonding is required to be omitted for safety reasons
(ii)wherescreenedsignalordatacablesareearthed,careshallbetakentolimitthefaultcurrentfrompower ' ' syst.-s flowirg thiough the screens and cores ofsignal cables or data cables
(iii) '- '
to cany functional eafih currents having high The impedance ofequipotential bonding connections intended of multiple' ,t uti u" as lo\v"as practicable and this should be achieved by the use frequ"ncy "o.pon.nt, separated bolds that are as short as possible
NoTE:Wherebondsofuptolmetrelongareused,theilinductivereactanceandimpeclanceofloutecanbeleduced bychoosingaconductivebraido-rabondingstrap/strip(withawidt}tothicknessratioofatleast5:landa length to width ratio no greater than 5:1)'
(iv)
be made to BS EN 62305' Where a lightning protection system is installed, reference shall
444.5.3
Sizing and installation of copper bonding ring network conductors
Equipotentialbonding designed as
(i) (ii)
a
dimensions: bonding ring network shall have the following minimum nominal
Flat cross-section: 25 rrm x 3 mm Round diameter; 8 mm.
and on their passage through walls' Bare conducto$ shall be protected against cotrosion at their suppofis
444.5"3.1 Parts to be connected to the equipotential bonding network network: The following parts sha1l be comected to the equipotential bonding
(i)Metalliccontainment,conductivescreens,conductivesheathsoratmouringofdatatransmissioncablesor of idonnation technology equipment
(ii) (iii) (iv) (v)
Functional eafihing conductors ofantenna systems technology equipment Conductors ofthe eafthed pole of a DC suppty for inforrnation Functionalearthingconductors Protectivecorductom.
444.5-4 444.5.5 444.5.6
444.5.7 444.5.7
.'l
Not used Not used
Not used
technology Earthing arrangements and equipotential bonding of information purposes installations for f unctional Earthing busbar
Wheleanearthingbusbarisrequiredforfunctionalpurposes,considerationshallbegiventoextendingthemain ilformation technology i"""ir"fif the uuilding uv usir4 on" o. Inor" "utthlng busbars. This enables ""nirirg terminal by the shortest pmcticable loute from anf/ point in the installations to be connected to tfr. i""in "'u.tfri"g ofa significant amount busbar is erected to;upport the equipotential bonding network rrrj"ra-g.
wfr.*
,fr. earthing
given to the installation ofa bonding ring
a building, consideration shall be of irfomation technotogy "qrip-;niin iest', ionding n"twork; see Annex 4444 Frgwe A444 2' .orrdr",o, o,
"o*rrlon
earthing busbar throughout its length and to the consideration shall be given to the need for accessibility of the protect ion of bat'e conduclors to prer ent comosion'
444.5-7.2 Cross-sectional
area
ofthe earthing busbar
A per phase or more' the cross+ectional atea FoI installations connected to a suppty having a capacity of 200 be selected in accordance with Regulation of the earthing busbar shall b" ,;;i;; ttu. s"o ,r,nj "opp.r and shali 414.5.2(iti).
Folsupplieshavingacapacityoflessthan200Aperphasetheearlhingbusbarshaltbeselectedinaccordancewith Table 54.8.
WlreretheearlhingbusbarisusedaspartofaDCretumculfentpath.itscloss-Sectionalareaslrallbl]selected accordi[g to the expected DC retun'] currents'
-
lLa
444.6
Segregation of circuits
444.6.1
General
Band I (exta-low voltage) cables that are used at voltage Band II (low voltage) and cables that ate used at voltage to the Iequilements which share the same cable management system oI the same foute, shall be installed accolding oI separation' segregatior'r ofRegulations 528.1 and 528.2. Circuits oi the same voltage band might also require
oI sepalation Iequilements' Electrical safety and eleckomagnetic compatibility might pfoduce different segregation The design shall meet both rcquiements.
444.6.2
Equipment
and mercury vapour (or other The minimum distance between information technology cables and discharge, neon (cfl) are to be considered as gas lamps Iow energy frig'h-ir|*riry a".harge) lamps shall be 130 mm. In this regard, separated' be always diicharge sources. Data wiring racks and electrical equipment shall
'1
15
AN
N
EX A444
(lnformative)
MEASURES AGAINST ELECTROMAGNETIC DISTU RBANCES
A444,1
Structures for the network of bonding conductors and earthing conductors
For dwellings, where normally a limited amount of elechonic equipment is in use, a protective conductor nefwork in the folm of a star network might be acceptable.
For commercial and in{ustrial buildings and similar buildings containing multiple electonic applications,
a
common equipotential bonding system is useful in order to comply with the EMC requirements of different types of equipment. The four basic structures described as follows might be used, depending on the impodance and vulnerability
of
equipment.
NOTE:
For fufiher infomation, the methodology refered to ir Bs EN 50310 (The application of equipotentiai bonding and earthing in buildings with information technology equipment) is generally applicable'
A444.1.1 Protective conductors in a star network commercial buildings, This tlpe of network is applicable to small installations associated with dwellings, small Figure A444 1' froln u g.reral point of view to equipment that is not interconnected by signal cables; see
"t".,
^d
Fig A444,1- Example of protective conductors in star network Dislribution
(r,1ET)
Eanhing conductor
-
Proiective conductor
-
A444.1.2 Multiple meshed bonding star network groups ofinterconnected comlnunicating This tlpe ofnetwork is applicable to small installations with different small Figure 4444 2' It enables thelocal dispersion of curents caused by electromagnetic interference; see
"qripil*,.
Fig A444.2
-
_
116
-
Example of multiple meshed bonding star network
Proiective condlctoE and/ortunctionaL earthing conduclors Functiona bondng conductors. The ength oi these conducrors should be as shon as possible (ior inslan@ < 50 cm)
A444.1.3 Common meshed bonding star network This type ofnetwork is applicable to installations with a high densiry of communic.ri.i: critical applications; see iigure 4444.3. It is suitable forprotection ofpdvate auromaii-(PABX) and cenffalized data processing systems.
A meshed equipotential bonding network is supplemented by conducton foming
enhanced
::-:r:nent corresponding to r.::.-l- .\!-hange equipment
by the existing metallic strucrrr:e oi rhe building lt is
the square mesh.
The mesh size depends on the selected level ofprotection against lightning, on the and on the lrequencies used lor data transmission
imlruniq
1er
el ofthe equipment
be in accordance rvith Mesh size should be adapted to the dimensions ofthe installation to be protected and should be adapted ro the dime sions the recommendations of BS EN 50310. Where concems exist, the mesh size should susceptible to of the installation to be protected, but should not exceed 2 m x 2 m in areas where equipment electromagnetic environmental interferences is installed
NOTE: In some
the mesh. The mesh size refers to the dimensions of square spaces enclosed by the conductors fonning cases, parts
ofthis network may be meshed more closely in order to meet specific requirernents'
Fig A444.3
-
Example of a common meshed bonding star network
Bonding conneclion
Current.using equipment
Main
terminal(s) (t\,4ET)
Functional bonding conduciors. The length of these conductorc shou d be as short as possible (ior instance < 50 cm)
A444.1.4 Protective conductors connected to a bonding ring conductor A444.4 onthe An equipotential bonding network in the form ofa bonding ng conductol (BRC) is shown in Figure in such a installed and insulated, or bare of copper, be made preferably top noo, oftt e ,mr.rrr"l Th. BRC should (see BS EN conduit a metallic tray, in a cable on mounting e.g. by l1ranner that it remains accessible everywhere, functional plotective and All trunking. cable oI installatioll of mounted method 61386 series), employing a surface earthing conductors may be connected to the BRC.
A444.2
Equipotential bonding networks in buildings with several floors
be installed: Forbuildings with several floors, it is recommended that, on each floor, an equipotential bonding system is a type of network The bonding see Fig,.rre i444.4 for examples of bonding networks in common use; each floor with systeis ofthe different floors should be iiterconnected, at least twice, by conductors selected in accordance
the requirements olChapter 54.
6Sctnrc^ (r-
od\
LIBRARY E 117
Fig A444.4
-
Example of equipotential bonding networks in a structure without a lightning
protection system
Equipotential BRC bonding network
Common meshed bonding network
Multiple star/mesh bonding network
Main earthing terminal(s) star bonding network
Structural metalwork
A444.3
lnstallations containing a high density of interconnected equipment
In severe electomagnetic environments, it is Iecommended that the common meshed bonding star network described in 4444.1.3 be adopted.
A444.4
Design guidelines for segregation of circuits
where both the specification of the information technology cable and its intended application is known, the requirements ofBS EN 50174-2 and BS EN 50174-3 are appropriate. BS EN 50174 sedes standards contain requirements and recommendations for the installation of infomtation technology cabling which suppofi a range ofapplications delivering the following selices:
(i) ICT (informatioll communication technologies) e.g. local area networks (ii) BCT (broadcast communication technologies) e.g. audio-visual, television (iii) CCCB (command control and communications in buildings) e g building automation (iv) pMCA (process monitorirg, control and automation) e.g. industrial networks (Fieldbus). then the Where the specification and/or intended application of the information technology cable is not available, mm 200 minimum of cable separation distance between the powir and information technology cables should be a
in free air. This distance can be reduced
in Table 4444.1.
118
ifa
screened power cable, a metallic barier, or containmellt system iS used as described
f ABLE 4444.1 - Summary of minimum separation distances where the specification and/or the intended application of the information technology cable is not available These recommendations of segrcgation are based upon the following assumptions:
(i)
The electromagnetic environment complies with the levels defined in the BS EN for conducted and radiated disturbances (e.g. mains power cabling)
(ii)
The LV supply is non-defomed but has high-ftequency content consistent with the switching and operation of connected equipment in accordance with the BS EN 61000-6 series olstandards NOTE: "Deformed" LV power supplies and the use ofother equipment lie outside the scope ofthis standard and might require additional enginee ng practices.
(iii) (iv)
6
1000-6 series of standards
The total desigll current in the LV circuits does not exceed 600A
Bala[ced information technology/telecommunications cables have electromagnetic immunity performance in accordance with BS EN 50288 series standards for Category 5 and above
(v)
Coaxial information technology/telecommunications cables have electromagnetic immunity performance in accordance with BS EN 50117-4-l standard for Category BCT-C
(vi)
The applications supported by the cabling are designed to operate using the information technology cabling installed or to be installed. Containment applied to the mains power cabling
No containment or open metallic containment Ar
Perforated open metallic containment
Solid metallic containment
B'
cr
200 mm
150
mm
Note 4
NOTE 1: Screening pefomance (DC-100MHz) equivalent to welded mesh steel basket ofmesh size 50 mm x 100 rrm (excluding laddels). This screening performance is also achieved with steel tray (duct without covo) of less than 1.0 mm wall thickness and more than 20% equally distributed peforated area. No part ofthe cable within the containment should be less than
l0 mm below the top of the ba1fier.
l 0 mm wall thickness and no more than 20% equally distributed pedorated area. This screening performance is also achieved with screened pou,er cables that do not meet the perfon'nance defined in Note 1. No part ofthe cable within the containment should be less tban 10 mm below the top ofthe banier.
NOTE 2: Screening performance (DC- 100 MHz) equivalent to steel tray (duct without cover) of
N
OTE 3: Scrcening pcrfor mance (DC 100 MHz) cquivalcllt to a fully cncloscd stccl containmert system having a minimum * all thickness of 1.5 mm. Separation specified is in additlon to that provided by any divider,/barrier.
NOTE 4: No physical separatior other than that provided by the containment.
NOTE:
Zero segregation in the Table references additional segregation/separation for EMC over and above the requiremerts for safety. Safety considerations must always take precedence over EMC requirements.
Where the above conditions do not apply, see Table A444.2.
TABLE A444.2 Power Cable Voltage (V)
-
Minimum separation between power and signal cables (m) Minimum Separation
Power Cable Current (A)
between Power and Signal
between Power and Signal Cables (m)
Cables (m)
t I
I I
N
Minimum Separation
115
0.25
5
0.24
240
0.45
15
0,3s
415
0.
s8
50
0.5
3300
1.1
100
0.6
6600
1.25
300
0.85
11000
t.4
600
1.05
OTE I : The values in Table A444.2 car be used specifically fol long parallel mns of cables.
NOTE 2: The uomrcase sepamtion based on voltage or curent should be used.
Additional areas ofconcem are expressed in Regulat ion 444.4.1.
h*
I
L. I 119
The minimum separation between the information technology cables and mains powercables includes all allowances for cable movement between their fixing points or other restraints (see example in Figure ,4444 5)'
Fig A444.5
Example of cable separation distance
-
I Separation
I
v
The minimun separatiol requirement applies in three dimensions. However, where infolmation technology be maintained then cables and mains fower cables are required to cross and required minimum separation cannot
less than the maintaining the angle of their crossing at 90 degrees on eithel side of the crossing for a distance no disturbances. electromagnetic applicabte irinimum separation requirement will minimize any
A444.5
Conditions for zero segregation
See BS EN 50174 series.
PROTECTION AGAINST UNDERVOLTAGE
445
General requirements
445.',|
Suitable precautions shall be taken where a reduction in voltage, or loss and subsequent Iestoration 1 3' ofvoltage, could caur. dung". Plovisions lor a circuit sr"rpplying a motor shall comply with Regulation 552
445.1.'l
it is where current-using equipment or any other pafi ofthe installation may be damaged by a drop in voltage and verified that such dJmage-is unlikely to cause danger, one ofthe following arrangements shall be adopted:
(i) (ii)
Suitable precautions against the damage foreseen shall be provided lt shall be verified, in consultation with the person or body responsible for the operation and maintenance the installation, that the damage foreseen is an acceptable fisk
of
if the A suitable time delay may be incorporated in the operation of an undewoltage protective device loss ofvoltage' or a briefreduction daDger without allows protection relates the operation ofthe equipment to whicir 445.1
.2
445.1
.g
a
Ary delay in the opening
or reclosing ofa contactor shall not impede instantaneous disconnection by
control device or a protective devrce.
for The characteristics ofan undervoltage protective device shall be comPatible with the requirements or Harmonized British starting and use of the equipment to which the protiction relates, as stated h the appropdate 445.1
.4
Standard.
445.1.5 automatic.
120
Where the reclosure of a protective device is likely to cause danger, the reclosure shall not be
CHAPTER 46 ISOLATION AND SWITCHING CONTENTS 460
SCOPE
461
GENERAL
462
ISOLATION
463
FUNCTIONAL swlrcHlNG (CONTROL)
463.1
General
463.2 463.3
Auxiliary circuits Motor control
464
SWITCHING OFF FOR MECHANICAL MAINTENANCE
465
EMERGENCY SWITCHING OFF
CHAPTER 46 ISOLATION AND SWITCHING SCOPE
460
Chapter 46 deals with:
(i)
for the prevention or removal of dangers non-automatic local and remote isolation and switching measures associatedwithelectricalinstallationsorelectricallypoweredequipment,and
(ii)
switching for the control ofcircuits or equipment'
ofBS EN 60204' only the requirements ofthat standard Where electrically powered equipment is within the scope apply. 461 461.1
GENERAL Accodingtotheintendedfunction(S),everydeviceplovidedforisolationorswitchingshallcomply
with the relevart requirements of Chapter 53'
:\e ,Je.
:by :: iOf
-zed
shall not be isolated or switched' In TN-C systems and TN-C-S systems, the PEN conductor is rotrequired ifprotective equipotential InTN-c-S andrN-S systems, isolation or switching ofthe neutal conductor bonding is installed and either: times of (i) the neutual conductor is reliably connected to Earth by.i1"t.*"1tl"i:t to meet the disconnection of Chapter 41' or the protective devices according to the requirements of the supply is reliably connected (ii) the distdbutor declares that either the PEN or the neutral conductor protective devices according to the the of to Earth by a low resistance to meet the disconlection times
461.2
requirements of ChaPter
.:
be
462 462.1
4l
ISOLATION ftom each supply' Each electuical installation shall have provisions for isolation
462,l.2olAmainlinkedswitchorlintedcircuit-br.eakershallbeprovidedasnearaspmcticabletotheorigin
ofJ""f iruuff",iot as a means
of switching the supply on load and as a means ofisolation'
A]nainswitchintendedforoperationbyordinarypersons,e.g.ofahouselroldorsimilarinstallatiorr,Shallinterrupt both live conductors of a single-phase supply'
live couductors' except as detailed in Every circuit shall be provided with isolation means for all 462.2 Regulation 461.2. by a common flIeans' ilthe sen'ice conditions allot'this Provision may be made for isolating a group of cicuits
r
462.3 -
Devices for isolation shall be designed and,/or installed so as to prcvent unintentional or inadvertent closure.
Located within a lockable space or lockable enclosure Padlocking Located adjacent to the associated equipment.
462.4
Where residual electdcal energy is potentially present, suitable means shall beprovided for its discharge.
Where relevant, a waming label indicating the discharge time required before the enclosure can be safely opened shall be provided.
NOTE:
Storage units do not need to be discharged since they are considered to be supply sources.
463 463.1
FUNCTTONALSWTTCHTNG(CONTROL)
General
463.1.1
Functional switching shall be provided for each part independently of other pafis of the installatiofl .
ofa circuit which may require to be controlled
463,1,2 Functional switching devices need not necessarily switch off alt live conductors of a circuit. A single-pole switching device shall not be placed in the neutral conductor except for the connection ofthe control device for lighting circuits as shown in Figure 46.1. Fig 46.1
-
Lamp control circuit with switching in the neutral conductor
Key
I 2 3
connection ofthe control device for lighting circuits
circuit supplying the lamps control device.
Switching ofthe neutral shall be in compliance with Regulation 530.3.3.
463.1.3
Iu general, all curent-using equipment requi ng conkol shall be controlled by functional switching device.
ar
appropriate
A single functional switching device may conhol seveml items of curent-using equipment interded to
operate
simultaneousll.
463.1.4
Functional switching devices ensuring the changeover ofsupply lrom altemative sources shall switch and shall not be capable ofputting the sources in parallel, unless the installation is specifically designed for this condition.
offa1llive conductors
l-
t"^
Auxiliary circuits
463.2
Auxiliary circuits shall be designed, aranged and protected to limit dangers resulting from a fault in the auxiliary circuit or an insulation fault between the auxiliary circuit and other conductive parts liable to cause malfunction (e.g. inadvertent operation) ofthe controlled apparatus; see Section 557.
463.3
Motor control
463.3.1
Motor control circuits shall be designed so as to prevent any motor from restading autornatically after a stoppage due to a fall in or loss ofvoltage, if such starting is liable to cause danger Earth laults in colltlol circuits should not cause unintentional stafiing, potentially hazardous motjon, or prevent stopping ofthe motor.
463.3.2
of
Where reverse-cunent braking of a motor is plovided, provision shall be made for the avoidance reversal ofthe direction ofrotation at the end ofbmking ifsuch reversal may cause danger.
463.3.3
Where safety depends on the direction of rotation prevention ofreverse operation due to a reversal ofphases.
NOTE:
of a motor, provision shall be made for
the
Attention is drawn to danger which may arise from the loss ofone phase.
SWITCHING OFF FOR MECHANICAL MAINTENANCE
464
Means for switching off shall be provided where mechanical maintenance may involve a risk 464.1 physical injury. The switching off shall cause the disconnection device suitable for isolation.
ofall live conductors, except
as
of
provided in Regulation 461.2, by a
NOTE 1: Electrically powered mechanical equipment may include rotating machines as well as heating elements and electromagnetic equipment.
NOTE 2: Systems powered by other means. e.g. pneumatic, hydraulic or steam, are I1ot covered by these ]egulations. In such cases, switching off any associated supply ofelectricity may not be a sufficient measure. NOTE 3: Where electrically powered equipment is within the scope of BS EN 60204, the requirements for switching off for mechanical maintcnance of thal standard apply.
464.2
Suitable means shall be provided to prevent electrically powered equipment from inadveftently or unintentionally reactivating during mechanical maintenance, unless the means of switching off is cortinuously under the control ofany person performing such maintenance.
465
EMERGENCY SWITCHING OFF
Means shall be provided for emergency switching necessary to control the supply to remove an unexpected danger. 465.1
465.2 offshall
off ofany part of
an installation where it may be
Where a risk ofelectdc shock or another risk of electrical origin is involved, the emergency srvitching cause the disconnection ofal1 live conductors, except as provided in Regulation 461.2, by a device suitable
for isolation.
465.3
Means for emergency switching
off shall act as directly as possible on the appropriate supply
conductors. The anangement for emergency switching offshall be such that one single action only supply.
will intenupt the appropriate
465.4 The armngement of the emergency switching shall be such that its operation does not introduce a fui1her danger or interfere with the complete operation necessary to remove the danger.
NOTE:
The operation ofthe switcling device is to be understood as switching offin case ofemergency and switching on to re-energize the relevant circuit.
The emergency operation function shall not impair the effectiveness ofprotective devices or of devices with other safety functiors.
123
PART 5 SELECTION AND ERECTION OF EQUIPMENT CONTENTS CHAPTER 51
COMMON RULES
510
INTRODUCTION
511
COMPLIANCE WITH STANDARDS
512
OPERATIONAL CONDITIONS AND EXTERNAL INFLUENCES
513
ACCESSIBILITY
s14
IDENTIFICATION AND NOTICES
515
PREVENTION OF MUTUAL DETRIMENTAL INFLUENCE
CHAPTER 52
SELECTION AND ERECTION OF WRING SYSTEMS
520
INTRODUCTION
521
TYPES OF WIRING SYSTEM
522
SELEfiON AND
523
CURRENT.CARRYING CAPACITIES OF CABLES
524
CROSS-SECTIONAL AREAS OF CONDUCTORS
525
VOLTAGE DROP IN CONSUMERS' INSTALLATIONS
526
ELECTRICAL CONNECTIONS
527
SELECTION AND ERECTION OF WRING SYSTEMS TO MINIMIZE THE SPREAD OF FIRE
528
PROXIMITY OF WIRING SYSTEMS TO OTHER SERVICES
529
SELECTION AND ERECTION OF WRING SYSTEMS IN RELATION TO MAINTAINABILITY INCLUDING CLEANING.
CHAPTER 53
PROTECTION, ISOLATION, SWITCHING, CONTROL AND MONITORING
530
INTRODUCTION
531
DEVICES FOR PROTECTION AGAINST ELECTRIC SHOCK BYAUTOMATIC DISCONNECTION OF SUPPLY
534
DEVICES FOR PROTECTION-AGAINST OVERVOLTAGE
535
DEVICES FOR PROTECTION AGAINST UNDERVOLTAGE
536
CO.ORDINATION OF ELECTRICAL EQUIPMENT FOR PROTECTION, ISOLATION, SWITCHING AND CONTROL
537
ISOLATION AND SWTCHING
538
MONITORING DEVICES
CHAPTER 54
EARTHING ARRANGEMENTS AND PROTECTIVE CONDUCTORS
541
GENERAL
542
EARTHING ARRANGEMENTS
543
PROTECTIVE CONDUCTORS
544
PROTEGTIVE BONDING CONDUCTORS
CHAPTER 55
OTHER EQUIPMENT
551
LOW VOLTAGE GENERATING SETS
552
ROTATING MACHINES
555
TRANSFORMERS
EREGTION OF WRING SYSTEMS IN REI.ATION TO
D$ERML INFLUENCES
557
AUXILIARY CIRCUITS
559
LUMINAIRES AND LIGHTING INSTALLATIONS
CHAPTER 56
SAFEry SERVICES
560.1
SCOPE
560.4
CLASSIFICATION
560.5
GENERAL
560.6
ELECTRICAL SOURCES FOR SAFETY SERVICES
560.7
CIRCUITS OF SAFEW SERVICES
560.8
WlRING SYSTEMS
560.9
EMERGENCY LIGHTING SYSTEMS
560.10
FIRE DETECTION AND FIRE ALARM SYSTEMS
560.'t1
LIFE SAFETY AND FIREFIGHTING APPLICATIONS
r"'"\ i,, urennnv '"
125
CHAPTER 51 GOMMON RULES CONTENTS CHAPTER 5,I
COMMON RULES
510
INTRODUCTION
510.'l
General
510.2
/Vot used
511
COMPLIANCE WITH STANDARDS
5'.l2
OPERATIONAL CONDITIONS AND EXTERNAL INFLUENCES
5',12.1
Operational conditions
512.1.1
Voltage
512.1.2
Current
512.',t.3
Frequency
512.1.4
Power
5',t2.1.5
Compatibility
512.1.6
lmpulse withstand voltage
512.2
External influences
513
ACCESSIBILITY
514
IDENTIFICATION AND NOTICES
514.',|
General
514.3
ldentification of conductors
5',14.4
ldentiflcation of conductors by colour
514.4.1
Neutral or midpoint conductor
s',t4.4.2
Protective conductor
514.4.3
PEN conductor
514.4.4 514,4.6
Other conductors Bare conductors
5'14.5
ldentification of conductors by letters and/or numbers
514.5.2
Protective conductor
514.5.3
Alphanumeric
514.5.4
Numeric
514.6
Omission of identification by colour or marking
514.7 s14.8
Not used
514,9
Diagrams and documentation
514.10
Warning notice: voltage
514.11
514.12
Warning notice: isolation Notices: periodic inspection and testing
5',t4.13
Warning notices: earthing and bonding connections
514.14
Warning notice: non-standard colours
514.15
Warning notice: alternative supplies Notice: high protective conductor current
514.16 515 515.1
't26
ldentification of a protective device
PREVENTION OF MUTUAL DETRIMENTAL INFLUENCE Prevention of mutual detrimental influence
CHAPTER 51 COMMON RULES 510
INTRODUCTION
s10.1
General
This chapter deals with the selection of equipment and its erection. lt provides common rules for compliance with measures of protection for safety, requirements for proper functioning lor il]tel]ded use of the installation, and requirements appropriate to the extenlal influences. /Vot used
510.2
s10.3
Every item ofequipment shall be selected and erected so as to allow compliance with the regulations stated in this chapter and the relevant regulations in other parts ofBS 7671 and shall take account ofmanufacturers' instructions.
COMPLIANCE WITH STANDARDS
511
Every itetr of equipment shall comply with the relevant requirements of the applicable Blitish or 511.1 Harmonized Standard, appropdate to the intended use of the equipment. The edition of the standard shall be the current edition, with those amendments pertaining at a date to be agreed by the paflies to the contract concerued (see
Appendix 1).
Altematively, ifequipment complying with a foreign national standard based on an IEC Standard is to be used, the designer or other person responsible lor specifying the installation shall verify that any differences between that stardard and the coffesponding British or Harmonized Standard will not result in a lesser degree of safety than that afforded by compliance with the British or Hamonized Standard. Such use shall be recorded on the appropriate electrical cerlilication specified in Parl 6. 511.2 Where equipment to be used is not covered by a British or Harmonized Standard or is to be used outside the scope ofits standard, the designer or other person responsible for specifying the installation shall conlinr] that the equipment provides at leasl thc samc dcgrcc of safcty as that affordcd by compliancc u,ith thc Rcgulations. Such use shall be noted and appended to the appropriate documertation specifled in Pal1 6.
512
OPERATIONAL CONDITIONS AND EXTERNAL INFLUENCES
512.1
Operational conditions
512.1.',|
Voltage
I I
I
Every item ofequipment shall be suitable for the nominal voltage (Uo) ofthe installation or the part ofthe installation concemed, where necessary taking account ofthe highest and/or lowest voltage likely to occur in nonnal service. In an IT system, equipment shall be insulated for the nominal voltage between lines.
512.1.2
Current
Every ite[r ofequipment shall be suitable for:
(i) (ii)
the design cun'ent, taking into account any capacitive and inductive effects, and
the current tikely to flow in abnormal conditions for such periods of time as are determined by the characteristics olthe protective devices concemed.
512.1.3
Frequency
If frequency
has an influence on the characteristics of the equipment, the rated frequency of the equipment shall conespond to the nominal frequency ofthe supply to the circuit concerned.
512.1.4
Power
Every item of equipment selected on the basis of its power chamctedstics shall be suitable for the duty demanded
oI the equipment.
^-.
127
512.1.5
Compatibility
Every ite[r ofequipment shall be selected and erected so that it will neither cause harmful effects to other equipment nol il1rpair the supply during normal service including switching operations.
Switchgear, protective devices, accessories and other types of equipment shall not be connected to conducton intended to operate at a temperature exceeding 70 'C at the ecluipment in normal service unless the equipment rnanufacturer has confinned that the equipment is suitable for such conditions, or the co[ductor size shall be chosen based on the cu-rent ratings for 70 'C cables ofa similar construction. See also Regulation 523.1 and Table 4A3. The designer ofthe fixed installatiol shall veri& that the installed fixed equipment, where releiant, is designed and manufactur-ed in accordance with EMC Directive 2014/30/EU and, upon request, the responsible person for the fixed installation shall provide the required documentation as specified by EMC Directive 2014/30/EU. NOTE
1
: lnfomatioll on tl'lc para eters to be considered is given in Scction 4,14. The level of detail of the documeotation may vary from very sinrple information to much more detailed documentation for complex irstallations involvilg irDportant poterltial EMC aspects.
NOTE 2: Thc responsible person ret'elred to in tbis regulation is as defined in the relcvant national legislation implementing EMC Directive 2014/3o/EU. In the UK, this is the Electromagnetic Compatibility Regulations 2016. The responsible person is the installer.
NOTE 3: Where installations are cornposed solely ofCE-mar*ed equiprnent placed on the market in confonnity with the EMC Directive, the responsible person satisfies the documentation requirements by being able to provide, on request, the instructions for installation, use and rnaintenance plovided by the supplier ofeach item of equipmeltt. NOTE 4: Where the current rating is to be based on 70 "C, cu(elt-carrying capacities given in Tables 4D1 to 4D5 or 4H I to 4H4 ofAppendix 4 rnay be used for 90 'C themosettirg insulated cables.
512.1.6
lmpulse withstand voltage
Equipment shall be selected so that its impulse withstand voltage is at least equal to the required minimum impulse withstand voltage according to the overvoltage category at the point ofinstallation as defined in Section 443.
5'12.2
External influences
512.2.1 Equipment shall be of a design appropriate to the situatior in which it is to be used or its mode installation shall take account ofthe conditions likely to be encountered. 512,2.2
of
If
the equipment does not, by its construction, have the characteristics relevant to the extemal influerces of its location, it may neveftheless be used on condition that it is provided with appropriate additional protection in the erection ofthe installation. Such protection shall not adversely affect the operation ofthe equipment thus protected.
512.2.3
Where different external influences occur simultaneously, they may have independent or mutual
effects and the degree ofprotection shall be provided accordingly.
512.2.4 The selection of equipment according to extemal influences is necessary not only for proper functioning, but also for the reliability of the measures of protection for safety complying with these Regulations generally. Measures ofprotection afforded by the construction ofequipment are valid only for the given conditions of extemal influence if the coruesponding equipment speciflcation tests are made in these conditions of extemal influence.
NOTE:
For the purposc of these Reglrlations, the following classes of extemal influence are conventionally regardcd
as
nonnal:
ternperature AB Atmosphcric humidity Other environrnental conditions
AA Ambient
AA4 AB4
xX I of
each pammeter
(AC to AS) Ulili./arion and
olbuildrrg. (B 513
consrruclion , xx I ofeach pararneler. exccpl I \X2 for rhe pararneter BC and C)
ACCESSIBILITY
Except for a joint in cables where Section 526 allo$,s such a joint to be inaccessible, evety item of 513.1 shall be aflanged so as to facilitate its opemtio[, inspection and mai]rtenal.Ice and access to each connection. equiprrent t'acility Such shall not be signillcantly impaired by mounting equipment in an elclosure or a comparlment.
514
IDENTIFICATION AND NOTICES
General
514.',1
514.',t .1 Except where tltere is no possibility ofconfusion, a label or othcr suitable nrea[s ofidentiflcation s]rall be provided to indicate the purpose ofeach item ofswitchgear and controlgear'. Where the operator camot obsenr'e the operation of su,itchgear and contrclgear and where this might lead to danger. a suitable indicator complying, where applicable, widr BS EN 60073 and BS EN 60447, shall be Iixed in a position visible to the operator.
514,1,2
So far as is reasonabiy practicable, u,iring shall be so aranged or marked that it can be identified
for
inspectiol, testing, repair or alteration ofthe installatiol.
514.1.3
Except where there is no possibility of confusion, unambiguous marking shall be provided at the interface between conductors identified in accordance with these Regulations and conductors idefltified to previous versions olthe Regulations.
NOTE:
Appendix 7 gives guidance on how this can be achieved.
514.2
Not used
514,3 ldentificationofconductors 5'14.3,1 Except where identification is not requircd by Regulation 514.6, cores ofcables shall be identified by: (i) colour as required by Regulation 514.4 and/or (ii) letters and/or numbers as required by Regulation 51,1.5. 514.3,2 Every core of a cable shall be identifiable at its terminations and preferably throughout its length. Binding and sleeves for identification purposes shall comply with BS 3858 whele appropliate.
514.4
ldentification of conductors by colour
514.4.'l
Neutral or midpoint conductor
Where a circuit jncludes a neutral or midpoint conductor identified by colour, the colour used shall be blue.
514.4.2 Protectiveconductor The bi-colour combination green-and-yellow shall be used exclusively for identification ol a protective conductor and this combination shall not be used for any other pur?ose. In this combination one of the colours shall cover at least 30 % and at most 70 % ofthe surlace being coloured, while the other colour shall cover the remainder ofthe surface. Single-core cables identified by green-and-yellow throughouttheir length shall only be used as a protective conductor and shall not be ovennar*ed at their teflninations, except as permitted by Regulation 514.4.3.
A bare couductor ol busbar used as a protective conductor shall be identified, where necessary, by equal green-andyellow stlipes, each not less than l5 mm a[d not more than 100 mlr wide, close together. either throughout the length ofthe conductor or in each compafiment and unit and at each accessible position.
514.4.3
PEN conductor
A PEN conductor shall, when insulated, be marked by one olthe lollowing methods:
(i) (ii)
Green-and-yellow throughout its length with, in addition, blue markings at the teminatiolls Blue throughout its lergth, with green-and-yellow ma*ings at the teminatjons.
514.4.4
Otherconductors
Other conductors shail be identified by colour in accordance with Table 51.
514.4.5 The single colour green shall not be used for the identification ol (i) live conductols in power circuits (ii) protectiveconductors (iii) functional ealthing and bonding conductors.
I
I
I
fFRIO,\ 9l
t"*oo ? 129
514.4.6
Bareconductors
A bare conductor shall be identified, where necessary, by the application oftape, sleeve or disc of the appropriate colour prescribed in Table 5l or by painting with such a colour.
514.5 514.5.1
ldentification of conductors by letters and/or numbers The lettering or numbe ng system applies to identification ofindividual conductors and ofconductors
in a group. The identification shall be clearly legible and durable. A11 characterc shall be in strong contrast to the colour of the insulation. The identification shall be given in letters and/or Arabic numerals. In order to avoid confusion. unattached numemls 6 and 9 shall be underlined.
5'14.5.2
Protectiveconductor
Conductors with green-and-yellow colour identification shall not be numbered other than for the purpose of circuit
identification.
514.5.3
Alphanumeric
The prefened alphanurne c system is described in Table 51.
514.5.4
Numeric
Conductors may be identified by numbers, the number 0 being reserued lor the neutml or midpoint conductor.
514.6 Omission of identification by colour or marking 514.6.1 Identiflcation by colour or marking is not required for: (i) (ii) (iii) (iv) (v)
130
concentric conductors of cables metal sheath or armour of cables when used as
a
protective conductor
bare conductors where pemanent identification is not practicable
extraneous-conductive-pafis used as a protective conductor exposed-conductive-pafis used as a protective conductor.
TABLE 51
-
ldentification of conductors
Function Proteclive conductors
Green-and-yellow
Functional earthing conductor
Cream
AC power circuit(r) Line of single-phase circuit
L
Brown
Neutral ofsingle- or three-phase circuit
N
Blue
Line
oftluee-phase AC circuit
LI
Brcwn
Line 2 oftltee-phase AC circuit
L2
Black
Line 3 ofthree-phase AC circuit
L3
Clcy
1
Two-wire unearthed DC porver circuit Positive of two-wire circuit
Brown
Negative of two-wire circuit
Grey
Trvo-rvire earthed DC potver circuit Positive (of negative eanhed) circuit
Brown
Negative (of negative eafihed) circuitrr)
Blue
Positive (of positive eathed) circuitrr'
BLue
Negative (of positive earthed) circuit
Grcy
-Ihree-wire
DC power circuit
Outer positive of two-wire three-wire system
ctcuit
derived
fron
Outer negative of two-wire circuit derived from three-wire system
Grey
Positive of three-wire circuit
Brcwn
Mid-wire of three-wire circuitrr)1r)
Blue
Negative of three-wire circuit
Grey
Control circuits, ELV and other applications Line conductor
Brown, Black, Red, Orange, Yellow, Violet, Grey, White, Pink or Turquoise
Neutral or mid-wireo)
Blue
NOTE:
(r'Power circuits include lighting circuits. 'rr M identifies either the mid-wire ofa three-wire DC circuit. or the eafthed conductor ofa two-wire eafthed DC circuit. 1r)Only the rniddle wire ofthree-wire circuits may be earthed. 1r)An earlhed PELV conductor is blue.
131
514.7
Not used
514.8
ldentification of a protective device A protective device shall be aranged and identified so that the circuit protected may be easily
514.8.1 recognized.
Diagrams and documentation
514.9 514.9.1 particular:
(i) (ii) (iii)
A legible diagram, chart or table or equivalent form of information shall be provided indicating in
the type and composition ofeach circuit (points ofutilization served, number and size ofconducto$, type olwiring), and the method used for compliance with Regulation 410.3.2, and
the infomation necessary for the identification of each device performing the functions of protection, isolation and switching, and its location, and
(iv)
any circuit or equipment vulnerable to the elect cal tests as required by Pafi 6.
For simple installations the foregoing information may be given in a schedule. A durable copy of the schedule relating to a distribution board shall be provided within or adjacent to each distribution board. Any slmbol used shall comply with IEC 60617.
514.'10
Warning notice: voltage
514.10.1 Every item ofequipment or enclosure within which a nominal voltage exceeding 230 volts to eafih exjsts and where the presence of such a voltage would not normally be expected, shall be so arranged that before access is gained to a live part, a waming ofthe maximum voltage to earth present is clearly visible. 514.11 Warning notice: isolation 514-1'1.1 A notice of such durable material as to be likety to remain easily legible throughout the life ofthe installation shall be fixed in each position where there are live parts which are not capable of being isolated by a single device. The location of each disconnector (isolator) shall be indicated unless there is no possibility of confusion.
514.12 Notices: periodic inspection and testing 514.12.1 A notjce of such durable materjal as to be likely
to remain easily legible throughout the life olthe installation shall be fixed in a prominent position at or near the origin ofevery installation upon completion ofthe work canied out in accordance with Chapter 64 or 65. The notice shall be inscribed in indelible characters not smaller than those illustrated here and shall read as follows:
IMPORTANT This installation should be periodically inspected and tested and a report on its condition obtained, as prescribed in the IET Wiring Regulations BS 7671 Requirements for Electrical Installations. Date of last inspection Recommended date of next inspection
514.12.2
Where an installation incorpomtes an RCD a notice shall be fixed in a prominent position at or near each RCD in the installation. The notice shall be inscribed in indelible characters not smaller thal those illustrated here and shall read as follows:
This installation, or part of it, is protected by a device which automatically switches off the supply if an earth fault develops.
'T'or
'Test'. The device should switch off the supply and should then be switched on to restore the supply. If the device does not switch off the supply when the button is pressed, seek expert advice. Test six-monthly by pressing the button marked
NOTE:
Testing frequencies ofRCDs i1l temporary installations may need increasrng.
514.13
Warning notices: earthing and bonding connections
5'14.13.1 A durable label to BS 951 with the words 'Safety Elechical Connection pemanently fixed in a visible position at or near:
-
Do Not Remove' shall be
(i) the point ofconnection of every earthing conductor to an eaflh electrode, and (ii) the point of connection of every bonding conductor to an exhaneous-conductive-part, and (iii) the main earthing terminal, where separate from main switchgear 514.13.2 Where Regulation 418.2.5 or 418.3 applies, the waming notice specilied shall be durably rrarked in legible type not smaller than that illustmted here and shall read as follows:
The protective bonding conductors associated with the electrical installation in this location MUST NOT BE CONNECTED TO EARTH.
Equipment having exposed-conductive-parts connected to earth must not be brought into this location.
514,14
Warning notice: non-standard colours
5'14.14.'l Ifwiring additions or alterations are made to an installation such that some ofthe widng complies with Regulation 514.4 but there is also wiring to a previous version ofthese Regulatioos, a waming notice shall be af6xed at or near the appropriate distribution board with the following wording;
CAUTION This installation has wiring colours to two versions of BS 7671. Great care should be taken before undertaking extension, alteration or repair that all conductors are correctly identified.
133
514.15
Warning notice: alternative supplies
5'14.15'1 Where an installation includes altemative or additional sources of supply, waming notices shall be aJnxed at the lollowing locations in the installation: (i) (ii) (iii) (iv)
At the origin ofthe installation
At the meterposition, ifremote from the origin At the consumer unit or distribution board to which the altemative or additional sources are connected At all points ofisolation ofall sources ofsupply.
The waming notice shall be durably marked in legible type not smaller than that illustrated here and shall read as
follows:
WARNING
- MULTIPLE SUPPLIES
Isolate all electrical supplies before carrying out work. Isolate the mains supply at Isolate the alternative supplies at
514.16 See
Notice: high protective conductor current
Regulation 543.7. 1.205.
515 515.1
PREVENTION OF MUTUAL DETRIMENTAL INFLUENCE
Prevention of mutual detrimental influence
Electrical equipment shall be selected and erected so as to avoid any hamful influence between the electrical installation and any non-electrical installations envisaged.
NOTE:
For EMC see Sections 332 and 444.
s',t5.2 Where equipment carying cuffent of different types or at different voltages is grouped in a common assembly (such as a switchboard, a cubicle or a control desk or box), all the equipment belonging to any one type of curent or any one voltage shall be effectively segregated wherever necessary to avoid mutual detdmental influence. The immunity levels of equipment shall be chosen taking into account the electromagnetic disturbances that can occur when connected and erected as for normal use, and taking into account the intended level of continuity of service necessary for the application. See the specilic equipment standard or the relevant pafi ofBS EN 61000 series.
134
CHAPTER 52 SELECTION AND ERECTION OF WIRING SYSTEMS CONTENTS 520 520.1
520.4 521 521.4 521.5 521 .5.1
521.5.201 521.6 521.7 521 .8
521 .9
521.10
522 522.1
522.2 522.4 522.5 522.6 522.7 522.8 522.9 522.10 522.11
522.12 522.13 522.14 522.15 523 523.5 523.6
INTRODUCTION Scope General TYPES OF WRING SYSTEM Busbar trunking systems and powertrack systems AC circuits: electromagnetic effects Ferromagnetic enclosures: electromagnetic effects Electromechanical stresses Conduit, ducting, trunking, tray and ladder systems Multicore cables: two or more circuits Circuit arrangements Use of flexible cables lnstallation of cables SELECTION AND ERECTION OF WIRING SYSTEMS IN RELATION TO EXTERNAL INFLUENCES Ambient temperature (AA) External heat sources Presence of water (AD) or high humidity (AB) Presence of solid foreign bodies (AE) Presence of corrosive or polluting substances (AF) lmpact (AG) Vibration (AH) Other mechanical stresses (AJ) Presence of flora and/or mould growth (AK) Presence of fauna (AL) Solar radiation (AN) and ultraviolet radiation Seismic effects (AP) Movement of air (AR) Nature of processed or stored materials (BE) Building design (CB)
523.201
CURRENT-CARRYING CAPACITIES OF CABLES Groups containing more than one circuit Number of loaded conductors Conductors in parallel Variation of installation conditions along a route Cables in thermal insulation Armoured single-core cables
524 524.2
CROSS-SECTIONAL AREAS OF CONDUCTORS Neutral conductors
525
VOLTAGE DROP IN CONSUMERS' INSTALLATIONS
526 526.9
ELECTRICAL CONNECTIONS Connection of multiwire, fine wire and very fine wire conductors
527 527.1
SELECTION AND ERECTION OF WRING SYSTEMS TO MINIMIZE THE SPREAD OF FIRE Precautions within a fi re-segregated compartment
527 .2
Sealing of wiring system penetrations
528
PROXIMITY OF WIRING SYSTEMS TO OTHER SERVICES Proximity to electrical services Proximity of communications cables Proximity to non-electrical services
523.8
Era o
528.1
528.2 529
SELECTION AND ERECTION OF WIRING SYSTEMS IN RELATION TO MAINTAINABILITY INCLUDING CLEANING.
135
CHAPTER 52 SELEGTION AND ERECTION OF WIRING SYSTEMS INTRODUCTION
520
Scope
520.1
This chapter deals with the selection ard erection of wiring systems.
NOTE:
These regulations also apply in geleral to protective conductors. Chapter 54 contains further rcquirements for those
conductols.
520.2 520.3 520.4
Not used
Not used General
Considemtion shall be givel to the application ofthe funda[rental principles ofChapter 13 as it applies to:
(i) (ii) (iii) (iv)
cables and conductors
their connections. teminations and/or jointing their associated supports or suspensions, and their enclosule or methods of protection against extemal influences.
521
TYPES OF WIRING SYSTEM
The requirelnents of Regulations 521.1 to 521.201 do not apply to busbar and powertrack systems covered by Regulation 521.4. Tl're rnstallation rncthocl ofa u,iring system in relation to the type ofconductor or cablc uscd shall be 521.1 in accorclancc with'Iable 4A1 ofAppendix,l, provided the extemal influcnccs arc taken into accoult accordit'tg to
Section 522. Thc ir'rstallation rnetlrod ofa wiring systcm in relation to the situation concemed shail be in accordance 521.2 with Table 4A2 ofAppcndix 4. Othel methods of installation ofcables and conductols no1 included in Table 4A2 are
pen]]itted provided that they fullil the requirements of this chapter.
521.3
Exanrplcs
of wiring
systems. excluding systcms coveled
by Regulation 521.4. are shown in
Table 4A2. Table 4A2 gives examples of installation methods of cables including reference method for obtaining curent-canJing capacity rvhere it is considered that the same cuffenlcarryi[g capacities can safely be used. It is not implied that such methods must be ernployed or that other methods are prohibited.
521.201 Prefabricatcd wiling systems intended lor permanent connection in fixed installations incorporating installation couplers corforming to BS EN 61535, shall comply with BS 8488. 521.4
Busbar trunking systems and powedrack systems
A busbar truntilg systeln shall comply with BS EN 61439-6 and a powefirack system shall comply with the approp ate part ofthe BS EN 61534 series. A busbar trunking system or a powefir'ack system shall be installed in accordancc wilh the manufacturcr's instructions, taking accoult ofextemal influences. See also Appendix 8.
52'1.5
AC circuits: electromagnetic effects
521.5.'l
Ferromagneticenclosures: electromagneticeffects
The conductols ofan AC circuit installed in a feron.ngnetic enclosure shall be aranged so that all line conductors and the neutral conductor, ifany. and the appropdate protective conductor are contajled within the same enclosure. Whcre such couductors eflter a ferrous cnclosure, they shall be affanged such that the conducton are only collectively sunouuded by f'cno[']agnetic Inaterial. These requirements do not preclude the use of an additional protective conductor in parallel with the steel wire
amouting of a cable wlrerc such is required to comply with the requirements of the appropriate regulations in Chapters 4l and 54. It is pemitted for such an additional protective corductor to enter the ferrous enclosure individually.
136
521.5'2 NOTE:
Singie-core cables armoured with steel wire or steel tape shall nor be gsed lor an AC circuit. The steel wire or sleel tape atmour of a single-core cable is legarded as a iifomasneric enclosure. For single-core armoured cables. the use
ofalulrinium armour may be considered.
52'1.5.201 Electromechanical stresses Every conductor or cable shall have adequate strength and be so installed as to Nitl'tstand the electromechanical lorces that may be caused by any current, including fault current, it nlay ha\ e to carry in service.
Conduit, ducting, trunking, tray and ladder systems
52',t.6
Two or more circuits are ailowed in the same conduit, ducting or trunking system provided the requirements
of
Section 528 are met. Cable conduits shall comply with the appropriate pafi of the BS EN 61386 series, cable trunking or ducting shall comply with the appropriate part of the BS EN 50085 series and cabJe tray and ladder systems shall co1nply with
BS EN 6I537.
Multicore cables: two or more circuits
521.7
Two or more circuits are allowed in the same cable provicled the requirements of Section 528 are met.
521.8
Circuitarrangements
521'8.'l Each part of a circuit shall be arrarged such that the conducton are not distributed over dillerent multicore cables, conduits, ducting systems, hxnking systems or tray or ladder systems. This requirement need not be met where a number of multicore cables, loming onc circuit, are installed in parallel. Where multicore cables are installed in parallel each cable shall contain one conductor ofeach line.
'8.2 The line and neutral conductors of each final circuit shall be elect cally separate fi om those of every other final circuit, so as to prevent the i[direcl energizing ofa final circuit intelded to be isolated. 52'l
521.8.3
whe,e rrv. or more circuits arc ter inated in a singlc.iunctirin box this shall comply with
BS EN 60670-22. 52',t.9
Use of flexible cables
A flexible cable shall be used lor fixed rviring only whcrc the relevant provisions ofthe Regulations met Flexible cables used for lixed wiring shall be of the heavy duty type unless the risk of darnagc during installation and service, due to impact or other mechanical stresses, is low or has been minimized or pr-otecrion 521.9.',1
are
against mechanical damage is provided.
NOTE:
Descriptions oflight, ordinary and heavy dury t)?es are given in BS EN 50565-1.
521 .9.2 Equipment that is irtended to be moved in use shall be comected by flexiblc cables! except equipmenr supplied by contact rails.
521.9.3 Stationary equipment which is movecl temporarily for the purposes of connecting. cleaning etc., e.g. cookers or flush-mounting units for installations in false floors, shall be connected with flexiblc cable. If the equipment is not subject to vibration then non-flexible cables may be used. 521.10 lnstallation of cables 52'1.10.1 Non-sheathed cables for fixed
wiring shall be enclosed in conduit, ducting or trunking. This
requirernent does not apply to a protective conductor complying with Section 543.
\on-sheathed cables are pelmitted if the cable trunking system provides at lcast the dcgree olprotectjon TPXXD or IP,lX. and ifthe cover can only be removed by means ofa tool or a deliberate action.
NOTE:
For a cable trunking system to meet IP.lX requirements. IP,IX ttunking and relatecl system components would need to be inslalled. lfa systetn includes sile-fabricated j oints the installer must confirln thc conlpietcd itenr rnccts at least thc degree of protection IPXXD.
521/10.201 A bare live conductor shall
be installed or insulators.
137
521.10.202 Widng
systems shall be supported such that they
will not
be liable to premature collapse in the event
ofa fire. NOTE 1: Wiring systems lranging across access or egress routes may hinder evacuation and firefighting activitics. NOTE 2: Cables installed in or on steel cable containment systems are deemed to meet the rcquirements ofthis rcgulation. NOTE 3: This regulation precludes, lor example, the use of non metallic cable clips or cable ties as the sole means of support where cables are clipped direct to exposed surfaces or suspended under cable tra1,, and the use ofnon-metallic cable trunking as the sole means of support ofthe cables therein. NOTE 4: Suitably spaced steel or copper clips, saddles or ties are examples that will meet the requirements ofthis regulation.
SELECTION AND ERECTION OF WIRING SYSTEMS IN RELATION TO EXTERNAL
522
INFLUENCES The installation method selected shall be such that protection against the expected extemal influences is provided in all appropriate parts ofthe widng systern. Particular care shall be taken at changes ir direction and where wiring enters into equipmenl.
NOTE:
The extemal influences categorized in Appendix 5 which are of signiflcance to wiring systems are included in this section.
Ambient temperature (AA)
522.1
522.1.1 A wiring system shali be selected and erected so as to be suitable for the highest ard lowest local ambient temperatures and so that the limiting temperature in normal opemtion (see Table 52.1) and the limiting temperature in case of a fault (see Table 43. i ) will not be exceeded.
522.'1.2 Wirilg system components, including cables and wiring accessories, shall only be installed or handled at tempemtures within the limits stated in the relevant product specification or as given by the manufactlrrer.
522.2
External heat sources
522.2.'l
In order to avoid the effects ofheat from external sources, one or more of the following methods or
an equally effective method shall be used to protect a wiring system:
(i) (ii) (iii) (iv)
Shielding Placing sufliciently far from the source of heat Selecting a system with due regard for the additional temperature se which may occur
Local reinforcement or substitution of insulating material.
NOTE:
Heat from extemal sources may be radiated, conducted or convected, e.g.: fiom hot water systems
-
from piant, appliances and luminaires from a manufacturing process through heat condrcting mate als
ftom solar gain ofthe wiring system or its surrounding medium.
522.2.201 Parts of a cable within an accessory appliance or luminaire shall be suitable for the temperatures Iikely to be encountered, as determined in accordance with Regulation 522.1.1, or sha11 be provided with additional insulation suitable for those temperatures.
522.3
Presence of water (AD) or high humidity (AB)
522.3.1
A wir ing system shall be selected and erected so that no damage is caused by condensation or ingress
ofwater during installation, use and maintenance. The completed wiring system shall comply with the IP degree of protection (see BS EN 60529) relevant to the pafticular location.
NOTE:
Special considerations apply to wiring systems iiable to frequent splashilg. inlnersion or submersion.
522.3.2
Where water may collect or condensation may form in a wiring system, provision shall be made for
its escape,
522.3.3 Where a wiring system may be subjected to waves (AD6), protection against mechanical damage shatl be afforded by one or more ofthe methods ofRegulations 522.6 to 8.
138
522.4
Presence of solid foreign bodies (AE)
522.4.1 Awiring system shall be selected and erected so as to minimize the danger adsing from the ingress of solid foreign bodies. The completed wiring system shall comply with the IP degree olprorection (see BS EN 60529) relevant to the particular location. 522,4,2 In a location where dust in significant quantib/ is present (AE4), additional precautions shall be taken to prevent the accumulation of dust or other substances in quantities which could adr,ersely affect heat dissipation from the wiring system. NOTE: Awiring system which facilitates
522.5
the removal ofdust may be necessary (see Secrion 529).
Presence of corrosive or polluting substances (AF)
522.5.1 Where the presence of corosive or polluting substances, including watel is likely to give se to colrosion or detedoration, parts ofthe wiring system likely to be affected shall be suitably protected or manufactued from a material resistant to such substances. NOTE:
Suitable protection for application during erection may include protective tapes, paints or grease.
522.5.2 Dissimilar metals liable to initiate electrol)'tic action shall not be placed in cortact with each other, unless special arrangements axe made to avoid the consequences ofsuch contact. 522.5.3
Materials liable to cause mutual or individual detedoration or hazardous degradation shall rot be
placed in contact with each other.
522.6
lmpact (AG)
522.6.1
Wiring systems shall be selected and erected so as to minimize the damage arising fiom mechanical stress, e.g. by impact, abrasion, penetration, tension or compression during installation, use or maintenance.
522.6.2 In a fixed installation where impacts of medium severity (AG2) or high severity (AG3) can occur protection shall be afforded by: (i) (ii) (iii) (iv)
the mechanical characteristics ofthe wiring system, or the location selected, or the provision of additional local or general protection against mechanical damage, or any combination ofthe above.
NOTE:
Examples are areas where the floor is likely to be penetrated and areas used by forklifi trucks.
522.6,3 522,6,4
Not used The degree ofprotection of electrical equipment shall be maintained after installation ofthe cables
and conducto$.
522.6.201
A cable installed under
a
floor or above
a
ceiling shall be run in such
a
position thar it is not liable to
be damaged by contact with the floor or ceiling or their fixings.
A cable passing through a joist within a floor or ceiling construction or through a ceiling suppoft (e.g.
under
floorboards), shall:
(i)
be installed at least 50 mm measured vertically from the top, or bottom as appropriate,
ofthejoist or batten,
OI
(ii)
comply with Regslatior, 522.6.204.
522,6,202 A cable
installed in a wall or partition at a depth of less than 50 mm from a surface of the wall or
paltition shall:
(i)
(ii)
be installed in a zone
within 150 mm from the top of the wall orpartition or within 150 mm ofan angle formed by two adjoining walls or partitions. Where the cable is comected to a point, accessory or switchgear on any surface of the wall or pafiition, the cable may be installed in a zone either ho zontally or vefiically, to the point, accessory or switchgear Where the location ofthe accessory point or switchgear can be detennined from the reverse side, a zone formed on one side of a wall of 100 mm thickness or less or pa ition of 100 mm thickness ol less extends to the reverse side, or
comply with Re glJarion 522.6.204.
Where indent (i) but not indent (ii) applies, the cable shall be provided with additional protection by means of an RCD having the characteristics specified in Regulation 415.1.1.
139
522.6.203 Inespective of its buried depth, a cable concealed in a wall or partition, the intemal construction which includes metallic parts, other than metallic fixings such as nails, screws and the like, shall:
(i)
be provided
of
with additional protection by means ofan RCD having the characteristics specified in Regulation
415. l. 1, or
(ii)
comply with Regulatior 522.6.204.
For a cable installed at a depth of less than 50 mm from the surface of a wall or partition the requirements of Regulation 522.6.202(i) shall also apply.
522.6.204
For the purposes ofRegulation 522.6.201(ii), Regulation 522.6.202(ii) and Regulation 522.6.203(ii),
a cable shall:
(i)
incorporate an eafihed metallic covering which complies with the requiremerts of these Regulations for a protective conductor of the circuit concemed, the cable complying with BS 5467, BS 6724, BS 7846, BS 8436 or BS EN 60702-1, or
(ii)
be installed in eathed conduit complying with BS EN 61386-21 and satisfliing the requirements ofthese Regulations for a protective conductor, or
(iii)
be enclosed in eafihed hunking or ducting complyingwith BS EN 50085-2-l and satisfying the requirements
ofthese Regulations for
(iv) (v)
a
protective conductor, or
be provided with n.rechanical protection against damage sufncient to prevent penetration of the cable by nails, screws and the like, or form part ol a SELV or PELV circuit meeting the requirements of Regulation 414.4.
Vibration (AH)
522.7
522.7.'l A widng system supported by or fixed to a structure or equipment subject to vibration of medium severity (AH2) or high seve ty (AH3) shall be suitable for such conditions, pafticularly where cables and cable connections are concemed.
522.7.2
For the fixed installation ofsuspended cuffent-using equipment, e.g. luminaires, connection shall be made by cable with flexible cores. Where no vibration or movement can be expected, cable with non-flexible cores may be used.
522.8 522.8.1
Other mechanical stresses (AJ)
A wiring system shall be selected and erected to avoid during installation, use or maintenance, damage to the sheath or insulation of cables and their teminations. The use of any lubricants that can have a det mental effect on the cable or wiring system are not permitted.
522.8-2 Wlere buried in the structure, a conduit system or cable ducting system, other than a pre-wired conduit assembly speciflcally designed for the installation, shall be completely erected between access points before any cable is drawn in. 522.8.3 The radius of every bend in a wiring system shall be such that conductors or cables do not suffer damage and terminations are not stressed. 522.8.4 Where conducto$ or cables are not supported continuously due to the method of installation, they shall be suppoted by suitable means at approp ate intervals h such a manner that the conductors or cables do not suffer damage by their own weight. 522.8.5 Every cable or conductor shall be supported in such a way that it is not exposed to undue mechanical strain and so that there is no appreciable mechanical stain on the teminations of the conductors, account being taken ofmechanical strain imposed by the supported weight ofthe cable or conductor itself. NOTE:
Consumer unit meter tails are included in the requirements
522,8.6
ofthis regulation.
A widng system intended for the drawing in or out ofconductors or cables shall have adequate means
ofaccess to allow this opemtion.
522.8.7
A wiring system buried in a floor shall be sufnciently protected to prevent damage caused by the
intended use ofthe floor.
522.8.8 522.8.9
140
Not used Nor used
522.8.'10 Except where installed in a conduit or duct which provides equi\ alenr protection against mechanical damage, a cable buried in the ground shall incorporate an earthed amour or metal sheath or both, suitable for use as a protective conductor The location ofburied cables shall be marked by cable cor ers or a suitable marker tape. Buried conduits and ducts shall be suitably identified. Buried cables, conduits and ducts shall be at a sufficient depth to avoid being damaged by any reasonably foreseeable disturbance ofthe ground. NOTE:
BS EN 61386-24 is the standard for underground conduits.
522.8.11 522.8.12 522.8.13
Cable supports and enclosures shall not have sharp edges liable to damage the wiring system.
A cable or conductors shall not be damaged by the means offixing. Cables, busbars and other electrical conductors which pass across expansion joints shall be so
selected or erected that anticipated movement does not cause damage to the electrical equipment.
522.8.14 No wiring system shall penetrate an element ofbuilding construction which is intended to be load bearing unless the integrity ofthe load-bearing element can be assured after such penetration.
522.9
Presence of ,lora and/or mould growth (AK)
522,9.1 Where the conditions experienced or expected constitute a hazard (AK2), the selected accordingly or special protective measures shall be adopted.
wi
ngsystem shallbe
NOTE 1: An installation method which facilitates the removal ofsuch growths may be necessary (see Section 529). NOTE 2: Possible preventive measures are closed types ofinstallation (conduit or channel), maintaining distances to plants alrd regular cleaning ofthe relevant wiring system.
522.10
Presence of fauna (AL)
522.10.1 Where conditions experienced or expected constitute a hazard (AL2). the wiring system shall be selected accordingly or special protective measures shall be adopted, for example, by: (i) (ii) (iii) (iv)
the mechanical characte stics ofthe wiring system, or
the location selected, or the provision of additional local or general protection against mechanical damage, or
any combination ofthe above.
Solar radiation (AN) and ultraviolet radiation
522.11
522.11.1 Where significant solar radiation (AN2) or ultraviolet radiation is experienced or expected, a wiring system suitable for the conditions shall be selected and erected or adequate shielding shall be provided. Special precautions may need to be taken for equipment subject to ionising radiation. NOTE:
See also
Regulation 522.2.1 dealing with temperature rise.
522.12
Seismic effects (AP)
522,12.'l
The wiring system shall be selected and erected with due regard to the seismic hazards ofthe location
ofthe installation.
522.122 Where the seismic hazards experienced are low seve ty (AP2) or higher, particular attention shall be paid to the following: (i) (ii)
The fixing of wiring systems to the building structure The connectiofls between the fixed winng and all items olessential equipment, e.g. safety services, shall be selected for their flexible quatity.
522.13
Movement of air (AR)
522.',13.1
See
522.14
Nature of processed or stored materials (BE)
Regulation 522.7, Mbration (AH), and Regulation 522.8, Other mechanical stresses (AJ).
522.14,1
See Section 527, Selection and erection of wiring systems Section 422, Precautions where particular risks offire exist.
522.15
to minimize the spread of fire and
Building design (CB)
522.15/l
Where risks due to structural rlovement exist (CB3), the cabte support and protection systern employed shall be capable of pennitting relati\,e movement so that conductors and cables are not subjected to excessive mechanical stress.
522.15.2
523
For a flexible structure or a structure intended to move (CB4), a flexible wiring system shall be used.
CURRENT-CARRYING CAPACITIES OF CABLES
523.1 The cufient, including any hannonic current, to be carried by any conductor for sustained periods during nomal operation shall be such that the appropriate temperature limit specified in Table 52.1 is not exceeded. The value of cunent shall be selected in accordance with Regulation 523.2, or determined in accordance with Regulation 523.3.
TABLE 52.1
-
Maximum operating temperatures for types of cable insulation limit'
Type ofinsulation
Theflroplastic
70 oC at the conductor
Thel.1nosetting
90 'C at the conductorb
Mireral (The.moplastic covered or bare
to touch)
Mineral (barc not exposed to touch and not in contact with combustjble matcrial)
70 "C at the sheath 105 "C at the sheathb
'
maxirnurn pennissiblc coflductor temperatures given in Table 52.1 on which the tabulated current-carrying capacihes given in Appendix 4 are based, have been taken from IEC 60502-1 and BS EN 60702-l and are shown on these tables in Appendix 4. 6 Where a conductor operates at a temperature exceeding 70 'C it shall be ascetained that the equipment connected to the
" The
conductor is srLitable for the .esultilg temperature at the connection. ' For ll1ireral insulated cables, higher operating temperatules may be permissible dependent upon the temperature rating of the cable, its terminations, the environmental conditions and other extemal influences.
NOTE:
For the telnperatrue
linits for othe|
types ofinsulation, refer to cable speciflcation or manufacturer
523.2 The requirement ol Regulatio[ 523. 1 is considered to be satisfied if tl']e curent fbr non-sheathcd and sheathed cables does not exceed the appropriate values seleated from the tables of curent-canJing capacity given in Appendix 4 with reference to Table 4A2, subject to any necessary mting factors.
NOTE:
The
curent-carying capacities given in the tables are provided for guidance. It is recognizcd that there will be some
tolerance in the current-calrying capacities depending on the environmental conditions and the precise construction
of
the cables.
The applopliate value of curent-carrying capacity may also be detennined as described in BS 7769 series (some parts of the BS 7769 seies are now numbered BS IEC 60287 series, eventually all pats will be renurbered). or by test. or by calculation usirg a recognized method, plovided that the method is stated. Where appropriate. accolLnt shall be taken olthe characteristics ofthe load and, for buried cables, the eflective thermal rcsistance ofthe soil.
523.3
523.4 The ambient temperature shall be considered to be the temperature ofthe surrounding medium when the non-sheathed or sheathed cable(s) under consideration are not loaded.
523.5
Groups containing more than one circuit
The group rating factors, see Tables 4Cl to 4C6 ofAppendix 4, are applicable to groups ofnon-sheathed or sheathed cables har ing the same ma"\imum operating temperarure.
For groups containing non-sheathed or sheathed cables having differ ent maximum operating temperatures, the curent-canling capacity of all the non-sheathed or sheathed cables in the grcup shall be based on the lowest maximum operating telrperature ofany cable in the group together with the appropdate group rating factol'. due to krown operating conditions, a non-sheathed or sheathed cable is expected to cary a current not greater than 30 % of its grouped curent-caffyirg capacity, it may be ignored for the purpose of obtainirg the rating factor for the rest ofthe group.
Il,
523.6
Number of loaded conductors
523.6.1
The number of conductors to be considered in a circuit are those carrying load cur:rent. Where conducto$ in polyphase circuits carry balanced cuffents, the associated neutral conductor need not be taken into consideratiou. Under these conditions a four-core cable is given the same cufient-carrying capacity as a threecore cable having the same conductor cross-sectional area for each line conductor The neutral conductot shall be considered as a loaded conductor in the case ofthe presence of third harmonic curent or multiples of the third harmonic presenting a total hamonic distoftion greater than 15 % ofthe fundamental line curfent.
142
I
523.6.2
Where the neutral conductor in a multicore cable carries curreni Li a result of an imbalance in the line cunents, the temperature se due to the neutml current is offset bl ihe reduciion in rhe heat generated by one or more ofthe line conductors. In this case the conductor size shall be chosen on the basis olthe highest line current.
In all
cases the neutral conductor shall have a cross-sectional area adequate to afford compliance with Regulation
523.t.
523.6.3
Where the neutal conductor carries curent without a corresponding reduction in load of the line
conductors, the neutual conductor shall be taken into account in ascertaining the cunent-canying capacity of the circuit. Such currents may be caused by a significant harmonic curent iII three-phase circuits. If the total harmonic distortion due to third harmonic current or multiples olthe third harmonic is greater than 15 % ofthe flindamental line crurent the neutral conductor shall not be smaller than the line conductors. Thermal effects due to the presence ofthird harmonic or multiples ofthird harmonic curents and the corresponding rating factors for higher harmonic cunents are given in Appendix 4, section 5.5.
523.6.4
Conductors which serve the purpose of protective conductors only are not to be taken into consideration. PEN conductors shall be taken into consideration in the same way as neutral conductors.
523.6.201 The tabulated current-carrying capacities in Appendix 4 are based on the fundamertal frequency only and do not take account ofthe effect ofharmonics. Conductors in parallel
523.7
Where two or more live conductors or PEN conductors are connected in parallel in a system, either:
(i)
measures shall be taken to achieve equal load current sharing between them
if the conductors are of the same material, have the same crosssectional area, are approximately the same length and have no branch circuits along their length, and either:
This requirement is considered to be fulIilled
(a) the conductors in parallel are multicore cables or twisted single-core cables or non-sheathed cables, ot (b) the conducton in parallel are non-twisted single-core cables or non-sheathed cables in trefoil or flat formation and where the cross-sectional area is greater than 50 mmz in copper or 70 mnf in alun.rinium,
the special configuration necessary for such formations is adopted. These conigumtions consist
ol
suitable groupings and spacings ofthe different lines or poles
or
(ii)
special consideration shall be given to the load curent sha ng to meet the requirements of Regulation 523.1.
This regulation does not preclude the use of ring final circuits with or without spur connections. Where adequate current sharing is not possible or where four or more conductors have to be connected in parallel consideration shall be given to the use ofbusbar trunking.
523,8
Variation of installation conditions along a route
Where the heat dissipation differs from one part ofa route to another, the current-carrying capacity ofcables at each pafi ofthe route shall be appropriate for that part ofthe route.
523.9 !
Cables in thermal insulation
A cable should preferably not be installed in a location where it is liable to be covered by themal insulation. Where a cable is to be run in a space to which thermal insulation is likely to be applied it shall, wherever practicable, be fixed in a position such that it will not be covered by the themal insulation. Where fixing in such a position is impracticable the cross-sectional area ofthe cable shall be selected to meet the requirements ofChapter 43. Where necessary, the nature ofthe load (e.g. cyclic) and diversity may be taken into account. For a cable installed in a themally insulated wall or above a themally insulated ceiling. the cable being in contact with a thermally conductive surface on one side, curent-carrying capacities are tabulated in Appendix 4. For a single cable likely to be totally surounded by themally insulating mate al o\'er a length of 0.5 11 or more, the current-carrying capacity shall be taken, in the absence of more precise infonration. as 0.5 times the cun'e[tcanying capacity for that cable clipped direct to a surface and open (Reference Method C). Where a cable is to be totally surounded by thermal insulation for less than 0.5 n] the currenGcanl,ing capacity of the cable shall be reduced appropriately depending on the size of cable, length in insulation and thetmal propenies of the insulation. The derating factors in Table 52.2 are appropriate to conductor size: up to 10 mmr in thermal insulation having a theflnal conductivity ().) greater than 0.04 Wm 1K '.
143
TABLE 52.2
-
Cable surrounded by thermal insulation
Length in insulation (mm)
Armoured single-core cables
523.201
The metallic sheaths and/or non-magnetic aunour of single-core cables in the same circuit shall normally be bonded together at both ends oftheir run (solid bonding). Alteruatively, the sheaths or amrour of such cables haviLrg colductors of cross-sectional area exceeding 50 mmr and a non-conductilg outer sheath may be bonded together at one poirt in thcir run (single point bonding) with suitable insulation at the unbonded ends. in which case the length ofthe cables from the bonding point shall be limited so that voltages from sheaths and/or amour to Eafih: (i) do not cause corosion when the cables are canying theil full load curent, for example by limiting the voltage to 25 V, atd
(ii)
do not cause danger or damage to property when the cables are carrying shofi-circuit cuffent.
CROSS.SECTIONAL AREAS OF CONDUCTORS
524
The cross-sectional area ofeach conductor in a circuit shall be not less than the values given in Table 52.3, except as prcvided for extralow voltage lighting installations according to Regulation 715.524.201
524.1
Neutral conductors
524.2
The neutral conductor, ifany, shall have a cross-sectional area not less than that ofthe line conductor:
524.2.1
(i) in single-phase, two-wire circuits, whatever the crcss-sectional
area
(ii) in polyphase and single-phase three-wire circuits, where the size ofthe line conductots is less than or equal to 16 mmr for copper, or 25 mm'? for aluminiun (iii) in circuits where it is required according to Regulation 523.6.3.
524.2.2
the total hannonic cortent due to tripler hamonics is greater thau 33 % of the fundamental line cuffent. an increase in the cross-sectional area ofthe neutral conductor may be required (see Regulation 523.6.3 and Appendix 4, section 5.5).
lf
For a polyphase circuit where each line conductor has a cross-sectional arca greatel than l6 mmr for mmr for aluminium, the ueutral conductor is permitted to have a smaller cross-sectional area than that or 25 copper provided that the followilg conditions are simultaneously fullllled: line corductors ofthe
524,2.3 (i)
The expected maximum current including harmonics, if any, in the neutml conductor duting normal service is not greater than the current-canying capacity olthe reduced cross-sectional area ofthe neutral conductor, and NOTE: The load carried by the circLLit under normal service conditions should be practicaily equally distributed between the lines. the 11eutra] colductor is protected against overcurlents according to Regulation '131.2, and the size ofthe neutral conductor is at least equal to 16 mmr fol copper or 25 mmr for aluminium, account
(i1)
(ii0
being taken ofRegulation 523.6.3.
TABLE 52.3 T]'pe of iviring system
Non sheathed and sheathed
-
Minimum cross-sectional area of conductors Use of the
circuit
Lightillg circuits
cables Pou,er cir-cuits
Si nallins
and control circuits
Conductor Cross-sectional area mm'?
Nlaterial Copper
1.0 (sce Note ,1)
I
Aluminiurn
l6
(see Note 3)
I
Coppcr
I.5 (see Note 3)
I
Aluminium
l6
Copper
0.5 (see Note 1)
Type of \r'iring system
Use
ofthe circuit
Non-sheathed and sheathed flexible cables
Cross-sectional area mm'?
Coppel
l0
Aiuminium
l6
Signalling and control cilcuits
Copper
1
For a specific appliarce
Copper
As specified in the product standard
Power circuits
Bare conductors
Conductor
llaterial
(see Note 3)
For any other application
0.75"
Extra-low voltage circuits for
0.75
special applications (see Note 2)
NOTE
l:
ln infonnation technology, signalling sectional area
ofo.l
and control circuits intended for electronic equipment a minimum cross-
mmr is permitted
NOTE 2: For special requiremerts for ELV liShting see Section 715. NOTE 3: Connectors used to tenninate aluminium conductoN shall be tested a[d approved for this specific use. NOTE 4l For lighting circuits and associated small items ofcurrent-using equipmert, slrch seven or inore cores. Note I
as a
bathroom extmctor fan
VOLTAGE DROP IN CONSUMERS' INSTALLATIONS
525
In the absence ofany other consideration, under normal service conditions the voltage at the terminals of any fined curent-using equipment shall be greater than the lower limit corresponding to the product standard rclevant to the equipment.
525.1
525.20,1 Where fixed curent-using equipment is not the subject ol a product standard the Yoltage at the terminals shall be such as not to impair the safe functioning ofthat equipment. The above requirements are deemed to be satisfied if the voltage drop between the origin of the installation (usually the supply terminals) and a socketoutlet or the te[minals offixed curent-using equipment does not exceed that stated in Appendix 4, section 6.4.
525.202
A greater voltage drop than stated in Apperdix 4, section 6.4 may be accepted for a notor dudng stafiing periods and for other equipment with high inrush currents, provided that it is verified that the voltage Yariations are within the limits specifled in the relevant product standard for the equipment ot, in the absence of a
525.203
product standard, in accordance with the manufacturer's recommendations.
ELECTRICAL CONNECTIONS
526
Every connection betweel condllctors or between a conductor and other equipment shalI provide
526.'t
durable electrical continuity atld adequate mechanical strength and protection.
NOTE:
Other mcchanical stuesses-
the material ofthe conductor and its insulation
(ii) the number and
-
-
The selection ofthe means ofcoDnection shall take account of, as apprcp ate:
526.2
(t
See Regulation 522-8
shape ofthe wires forming the conductor
(iii) the cross-sectional
area
ofthe conductor
(iv) the number ofconductom to be connected together (v)
the temperature attained at the tenninals in normal service such that the effectiveness ofthe insulation
ofthe
conducto$ colnected to them is not impaired
(\'i) the provision ofadequate locking arrangements in situations subject to vibration or thermal cycling ',i
here a soldered connection is used the design shall take account of creep, mechanical stress anci temperature rise
-:der fault conditions. raOTE
l:
ITOTE
2: Terminals without
Applicable standards include BS EN 609'17-7, the BS EN 60998 series and BS EN 61535' rhe marking
are suitable tbr the connection
:26.3
'r'(only dgid conductor). 'f'(only flexible conductor), 's'or 'sol'(only solid conductor)
ofall
tyPes ofconductors
Every connection shallbe accessible for ir'rspection. testing andmaintenance, except for the following:
Ajoint designed to be buried in the ground A cornpound-fi lled or encapsulatcdio,nt
---
145
(jii) A connection beflveen a cold rail and the heating element as in ceiling heating, floor heating or a trace heating system
(iv)
A
joint made by welding, soldering, brazing or appropriate compression tool
(v) Joints ot'connections made in equipment by the manufacturer ofthe product
and not intended to be inspected
or maintained
(vi)
Equipment complying with BS 5733 for a maintenance-free accessory and marked with the symbol and installed in accordance with the manufacturer,s instructions.
@
526.4 Where necessary precautions shall be taken so that the temperature attained by a connection in normal service shall not impair the effectiveness ofthe insulation ofthe conductors connected to it or any insulating material used to support the connection. Where a cable is to be connected to a bare conductor or busbar its type of insulation and/or sheath shall be suitable for the maximum operating temperature of the bare conductor or busbar Evely termination and joint in a live conductor or a pEN conductor shall be made within one ofthe fo1lowing or a combination thereof: 526.5
(i) (ii) (iii)
A suitable accessory complying with the appropriate product standard An equipment enclosure complying with the appropriate product standard An enclosure partially formed or completed with building material which is non-combustible when tested to BS 4'76-4.
526.6
There shall be no appreciable mechanical strain on the corulections ofconductors.
526.7 where a comection is made in an enclosure the enclosure shall provide adequate mechanical protection and protection against relevant extemal influences.
526.8 Cores of sheathed cables from which the sheath has been removed and non-sheathed cables at the tennination ofconduit, ducting or tluf
Connection of multiwire, fine wire and very fine wire conductors
526.9.1 ln order to avoid inappropriate separation or spreading of individual wires of multiwire, fine wire or very fine wire conductors. suitable temlillals shall be used or the condlLctor ends shall be suitabiy treated.
526.9.2 Soldering (tinning) ofthe wholc conductor end of multiwire. fine wire and very fine wire conductors is not permitted ifscrew terminals are used.
526.9.3
Soldered (tinned) conductor ends on line wire and very flne wire conducto$ are not permissible at connection and junction points which are subject in seryice to a relative movement between the soldered and the non-soldered part of the conductor.
527
SELECTION AND ERECTION OF WRING SYSTEMS TO MINIMIZE THE SPREAD OF FIRE
Precautions within a fire-segregated compartment
527 .1
527.1.',| The risk ofspread accordance with Section 527.
NOTE:
offire shall be minimized by the selection of appropriate materials
and erection
in
A flre-segreSated compatment (fire cornpanment) is considered to be an enclosed space, which may be subdivided, separated from adjoining spaces within a building by elements ofconstrxction having a specified fire resistance.
.2
527 .'l A are not reduced.
527.1.3
wiling system shall
be installed so that the general building structural perfomance and fire safety
Cables complying with, at least, the requirements BS EN 60332-1-2 may be instalted without special
precautions. Where the fire-segregated compafiment provides a means of evacuation in an emergency then the cable shall meet the requirements ofthe appropdate part ofBS EN 60332-3 series.
NOTE:
Cables nlanufactured for the above application also need to satisfy the requirements
of the CPR in respect of their
reaction ro 1lre. See Appendix 2, item 17.
527.1.4
Cables not complling with the cable requirements of Regulation 527.1.3 shall be limited to short lengths fol connection of appliances to the pemanent wiring systerl and shall not pass frorri one fire-segregated compaft mer]t to another.
146
527.1.5
Products harins rhe necessa4 resistance to flame propagation as spccificd in the BS EN 61386 series, thc approprjate pan ol BS EN 50085 series. BS EN 61439-6, tsS EN 6lill scrics. BS EN 61537 or BS EN 60570 may be installed rvithout special precautions. Other products corlrplvin-s * ith standards haviug similar requirements lor resistance to flame propagation may be installed without special precaurions. 527 ,1.6 Pafis of wiring systerns other than cables which do nor compl1.. as a ninimum. with the flame propagation requirements as specified in the BS EN 61386 selies, the appropriate parr of BS EN 50085 selies, BS EN 61439-6, BS EN 6153,1 series or BS EN 61537 but which comply in all other respects with the requirements of their respectivc product standard shall, if used, be completely enclosed in suitable non-combustible building
materials.
527.2
Sealing of wiring system penetrations
527.2.1 Whele a wiling system passes through elements ofbuilding construction such as floors. walls, roofs, ceilings, patitions or cavity balriers, the openings remaining after passage of the wiring system shall be sealed according 1o the degree of fire-resistance (if any) prescribed for the respective element of building colstruction before penetration.
This requireme)rt is satisfied if the sealing of the wiring system concemed has passed a relevant type test meeting the requirements of Regutation 527.2.3. 527.2.1.1
During the erection of a wiring system tenporary sealing arangements shall be provided
as
approp at 527.2.1.2
During altemtion work, sealing which has been disturbed shall be reinstated as soon
as
practicable.
527.2.2 A wiring system such as a conduit systerr, cable ducting systen, cable trunking system, busbar or busbar trunking system which penetmtes elements of building construction having specified fire-resistance shall be internally sealed to the degree of fire-resistance of the respective element before penetration as well as being ertemally sealed as required by Regulation 521 .2.1. This requirement is satisfied if the sealing ofthe wiring system concemed has passed a relevant type test meeting the requirements of Regulation 527.2.3. 527 ,2.3 A conduit system, cable tmnking systera or cable ducting systenl classilied as non-flame propagating lccording to the relevant product standard and having a maximum intemal cross-sectional area of710 mmr need not b.' intemally sealed provided that:
(i) (ii)
the system satisfies the test olBS EN 60529 for IP33, and
any telnrination of the system in one of the compartments, separated by the building construction being penetrated, satisfies the test olBS EN 60529 for 1P33.
527.2.4
Any sealing an-angement intended to satisfy Regulation 527.2.1 or 527.2.1.1 shall resist external rfluences to the same degree as the wi ng system with which it is used and, in addition, it shall n.reet all olthe
r.11os,in g requirements
li)
:
It shall be resistant to the products ofcombustion to the same extent asthe elements ofbuilding construction rvhich have been penetrated
t
ii) It shall provide the same degree
of protection from water penetration as that required for the building constmction element in which it has been installed
ll
I
It shall be compatible with the matedal ofthe widng system with which it is in contact It shall permit thermal movement ofthe wiring systern without reduction ofthe sealing quality It shall be of adequate mechanical stability to withstand the stresses which nlay suppofi ofthe wiring system due to fire.
a
se through damage to the
:- .:iil and the \!iring system shall be plotected tiol]r drippirg r,r,ater utich may travel along the wiring system or : ,:: maY otherwise collcct around the seal unless the n.iaterials used in the seal are all resistant to nloisture $,her]
- .
'. rssembled for
\ f,TE:
use.
This regulation ma), be sarisf,ed ifi either cable cleats, cable ties or cable supports are installed rvithin 750 mm ofthe seal, and are able to withstand thc mechanical loads expected following the collapse ofthe supports on the fire side ofthe seal to the extent that
no strain is hansferred to the seal or the design
ofthe sealing syste itselfpr-olides adequate suppol1.
147
528
PROXIMITY OF WIRING SYSTEMS TO OTHER SERVICES
Proximity to electrical services
528.1
Except where one ofthe following methods is adopted, neither a voltage Band I nor a voltage Band II circuit shall be contained in the same wiring system as a circuit ofnominal voltage exceeding that of low: voltage, and a Band I circuit shall not be contained in the same wiring system as a Band II circuit:
(i) (ii) (iii)
Every cable or conductor is insulated for the highest voltage present Each conductor of a multicore cable is insulated for the highest voltage present in the cable The cables are insulated for their system voltage and installed in a separate compaftment of a cable ducting or cable trunking system
(iv) The cables are installed on a cable tray system where physical separation
is provided by a parrition
(v) A separate conduit, trunking or ducting system is employed
(vi) For a multicore cable, the
cores ofthe Band I circuit are separated from the cores ofthe Band II circuit by an earthed metal screen ofequivalent current-carrying capacity to that ofthe largest core ofa Band II cfu;it.
For SELV and PELV systems the requirements ofRegulation 414.4 shall apply. NOTE 1: In the case of proximity of wiriflg systems and lightning prorection systems, BS EN 62305 should be considered. NOTE 2; Recornmendations for separation and segregation in relation to safety ser,iices are given in BS 5266, BS 5g39 and BS 8519.
528.2
Proximity of communications cables
In the event of crossing or proximity ofunderground telecommunication cables and underground power cables, a minimum clearance of 100 mm shalt be maintained, or the requirements according to (i) or (ii) shali be fulfilled:
(i) A fire-retardant
(ii)
partition shall be provided between the cables, e.g. bricks, cable protecting caps (clay, concrete), shaped blocks (concrete), protective cable conduit or troughs made offire-retardant mate als For crossings, mechanical protection between the cables shall be provided, e.g. cable conduit, concrete cable protecting caps or shaped blocks.
NOTE 1: Special considerations ofelectical intederence, both electromagfletic
artd electrostatic, may apply to
te]ecommunication
circuits, data transfer circuits and the like.
NOTE 2: Segregation requirements for communications services are given in BS 6701 and BS EN 50174 series.
528.3
Proximity to non-electrical services
528.3,1 A wiring system shall not be installed in the vicinity of services which produce heat, smoke or firmes likely to be detrimental to the widng, unless it is protected from harmful effects by shielding ananged so as not to affect the dissipation o[hear from the wiring. In areas not specifically designed lor the installation of cables, e.g. service shafts and cavities, the cables shall be
laid so that they are not exposed to any harmful influence by the normal operation ofadjacent installations (e.g. gas, water or steam [ines).
528.3.2 Where a wiring system is routed below services liable to cause condensation (such as water, steam or gas services), precautions shall be taken to protect the wiring system from deleterious effects. 528.3.3 Where an electrical seryice is to be installed in proximity to one or more non-electrical services it shall be so aranged that any foreseeable operation carried out on the other services will not cause damage to the electrical service or the converse. NOTE:
This may be achieved by: (i) suitable spaciflg between the services, or (ii) the use of mechanical or themal shieldins.
528.3,4 Where an electrical service is located in close proximity to one or more non-electrical seruices, both the following conditions shall be met: (i) (ii)
The wiring system shall be suitably protected against the hazards likely to arise fiom the presence ofthe other services in nomal use Fautt protection shall be afforded in accordance with the requirements of Section 4l
NOTE;
_148
_
.
The requirements for segregation between low pressure gas systems and electrical equipment are grven in BS 6891.
528.3.5 BS EN
1
8l
No cable shall be run in a lift or hoist well unless it forms part ofthe lift installation as defined in
series.
SELECTION AND ERECTION OF WRING SYSTEMS IN RELATION TO MAINTAINABILITY, INCLUDING CLEANING 529,1
With regard to maintainabiliry reference shall be made to Regulation 1i2.12.
Where it is necessary to remove any protective measure in order to carry out maintenance, provision shall be made so that the protective measure can be reinstated without rcduction ofthe degree ofprotection originally intended.
529.2
529.3
Provision shall be made for safe and adequate access to all parts of a
wi
ng system which may
requlre marntenance.
NOTE:
In some situations, it may be necessary to provide permanent means ofaccess by ladders, walkways, etc.
149
CHAPTER 53 PROTECTION, ISOLATION, SWITGHING, CONTROL
AND MONITORING CONTENTS 530
INTRODUCTION
530.1
Scope
530.2
Not used
530.3
General and common requirements
530.4
Fixing of equipment
531
DEVICES FOR PROTECTION AGAINST ELECTRIC SHOCK BYAUTOMATIC DISCONNECTION OF SUPPLY
cJt.t
General
531 .2
531.2.1
Overcurrent protective devices General
531 .2.2
TN systems
531.2.3
TT systems
531 .2.4
531 .3
lT systems Residual current devices (RCDs)
531.3.1
General
531.3.2
Unwanted tripping
531.3.4 531.3.5
Selection according to the accessibility to the installation RCDs for fault protection
cJ t.J.o
RCDs for additional protection
532
DEVICES FOR PROTECTION AGAINST THE RISK OF FIRE General
Types of RCD
532.1
532.2
532.4 532.5 532.6 533
lnternal arc fault protection in a switchgear and controlgear assembly Arc fault detection devices (AFDDs)
533.1
DEVICES FOR PROTECTION AGAINST OVERCURRENT General requirements
533.1.1
Compliance with standards
533.1.2
Fuses
533.1.3
Circuit-breakers
533.2 533.3
Selection of devices for overload protection of wiring systems Additional requirements for protection against overload when harmonic currents are present Selection of devices for protection of wiring systems against fault current
534
DEVICES FOR PROTECTION AGAINST OVERVOLTAGE
533.2.2
150
Residual current devices (RCDs) for protection against the risk of flre Residual current monitoring devices (RC[,4s) for protection against the risk of fire in lT systems lnsulation monitoring devices (lMDs) for protection against the risk of fire in lT systems
534.1
General
534.4
Selection and erection of SPDs
534.4.1
SPD types and location
534.4.2
Connection modes of SPDs
534.4.3
Connection types
534.4.4
Selection of SPDs
534.4.5 534.4.6
Protection of the SPD against overcurrent Fault protection
534.4.7
SPD installation ln conjunciion with RCDS
_ ._
534.4.8
Connection of SPDs
I
534.4.10
Connecting conductors of SPDs
I
535
DEVICES FOR PROTECTION AGAINST UNDERVOLTAGE
536
CO-ORDINATION OF ELECTRICAL EQUIPMENT FOR PROTECTION, ISOLATION,
SWTCHING AND CONTROL 536.1
General
536.2
Electrical devices considered and function provided
536.3
Co-ordination requirements
536.4
Requirements for selectivity
536.4.1
General
536.4.2
Requirements for protection in case of short-circuit Requirements for protection in case of overload Requirements for selectivity betlveen OCPDs equipped with under voltage relay
536.4.3 536.4.4 536.4.20',1
Low voltage assemblies according to BS EN 61439 series Fault current (short-circuit) ratings
536.4.202
Current ratings
536.4.203
lntegration of devices and components
536.5
Documentation
536.4.5
537
ISOLATION AND SWITCHING
537 .1
General
537.2
Devices for isolation
537.3
Devices for switching
537.3.1 537 .3.2
Functional switching and control devices Devices for switching off for mechanical maintenance
537.3.3
Devices for emergency switching off
537 .4
Firefighter's switches
538
MONITORING DEVICES lnsulation monitoring devices(lMDs) for lT systems
538,1 538.1
.1
General
538.1.3
lnstallation of insulation monitoring devices Setting of the insulation monitoring device
538.2
Equipment for insulation fault location in lT systems
538.3
lilonitoring of offline circuits
538.1.2
538.4
Residual current monitors(RCMs)
538.4.1
General
538.4.2
RCMS installed in lT systems
CHAPTER 53 PROTECTION, ISOLATION, SWITCHING, CONTROL
AND MONITORING
530 530.1
INTRODUCTION
Scope
This chapter deals with general requirements for protection, isolation, switching, control and monitoring and with the requirements for selection and erection ofthe devices provided to fulfil such functions.
NOTE:
In Chapter 53, reference to short-circoit, where relevant, includes earth fault. Shoft-circuit Protective Device (SCPD), where relevant, also means earth fauh curent protective device.
530.2
Nof used
s30.3
General and common requirements
530.3.1
Every item ofequipment shall be selected and erected so as to allow compliance with the requirements
stated in the following regulations.
530.3.2
The noving contacts of multipole switching devices marked for the connection of the neutral or midpoint may close before and open alter the other contacts.
530.3.3 530.3.4
A switching device shall not be inserted in the neutal conductor alone.
530.3.5
Equipment irtended for protection only shall not be provided for functional switching olcircuits.
Devices embodying more than one function, as defined in the following regulations, shall comply with the relevant requirements of this chapter approp ate to each separate function.
NOTE:
See Table
537.4 - Guidance on the selection ofprotective. isolatior amd switching devices.
Fixing of equipment
530.4
530.4,1 Taking into account the rnanufacturer's instructions, if any, equipment shall be erected in such a way that connections between wiring and equipment shall not be subject to undue stress or stmin resulting from the nonnal use ofthe equiptnent. 530.4,2
Unelclosed equipnent shall be mounted in a suitable mounting box or enclosure in compliance with the relevant part ofBS EN 60670, BS EN 62208 or other relevant standards such as BS EN 61439 series. Socketoutlets, connectiol units, plate switches and similar accessories shall be fitted to a mounting box complying with BS 4662 or BS 5733 and with the relevant pafi ofBS EN 60670.
530.4.3
Equipment such as circuit-bleakers, switches, socket-outlets, control equipment, etc. may be installed on or in a cable tnlnking system complying with BS EN 50085 series. Wherever equipment is fixed on or in cable trunkirg, skirting trunking or in mouldings it shall not be fixed on covers which can be removed inadvefiently.
531
DEVICES FOR PROTECTION AGAINST ELECTRIC SHOCK BY AUTOMATIC DISCONNECTION OF SUPPLY
531.1
General
531.1.1
Devices for protection against clectric shock by automatic disconnection ofsupply shall be suitable
1br isolation in accordance with Chapter 46 ard Section 537.
Automatic reclosing of devices for protection against elect c slrock by automatic disconnection of supply shall only be installed in the associated part of the installation where access is rest cted to instructed persons or skilled person\ onlY.
Awarning notice shall be clearly displayed nearthe point ofaccess to the associated part ofthe installation controlled by the auto-reclosing device, indicating its automatic reclose function must be disengaged prior to entry.
NOTE:
Automatic Reclosing Devices are intended to reclose circuit-breakers, RCBOs and RCCBs after tripping, in order to r(-<.ldl_li-h ionlrnLri(y ol'ser1 ice.
diSconnection of supply Requirements for the selection of devices fol plotection against electric shock b) automatic are given in the regulations listed below.
Il
TN, TT and IT systems the following protective devices may be used: (i) overcufient protective devices, in accordance with Regulation 531'2 (ii) residual curent devices (RCDs), in accordance with Regulation 531 '3 '
by the symbol Devices according to BS EN 60947-2 marked with the voltage value followed voltage. in IT systems for such
@
shall not be used
fault conditions: In addition. in IT systems the following monitoring devices may be used to detect insulation (iii) insulation monitoring devices (IMDS), in accordance with Regulation 538 1
(iv) equipment for insulation fault location, in accordance with Regulation 538 2 (v) residual cunent rnonitors (RCMs), in accordance with Regulation 538.4'
I
I
531.2
Overcurrentprotectivedevices
531.2.1
General
automatic disconnection of where ovefcuTent protective devices are used for protection against electric shock by supply they shall be selected in accordance with Section 533'
531.2.2 I
TN systems
fault protection shall be selected and elected In TN systems, ovefcurent protective devices when used as devices for (see particular Regulation 4l L4.4). in 4l *ith theiequirements specified in Chapter in ord"i to
"o-pty If.forceltahequipmentorforcertainparlsoftlreinstallation,themaximumdisconnectiontimesinTabl...ll,l cannotbefulfilledbytheovercurrentprotectivedevices,thosepafisshallbeprotectedbyalRCDincompliance with Regulation
53 1.3.5.2.
that the neutral conductor' In TN-S systems, the neutralneed not be disconnected ifthe supply conrlitions are such cau be considered to be reliably at earth potertial'
In TN-C systems, the PEN conductor shall not be disconnected'
531.2.?.201 Except in certain
overcurrent Special installations oI locations (Pafi 7), there is no rcquirement under
conditions to disconnect/switch the neutral in TT or TN systems'
531.2.3
TT systems
plovided that a suitably low value of In TT systems, overcurrent protective devices may be used for fault protection ofa fault, tdpping ofthe overcurrent in case that L5.4) so Z" is permanently and reliably assured (see Regulation 4l js achieved' times protective device in compliance with the required disconnection 53',1
lT systems
.2.4
second fault, shall comply overcurent protective devices, when used as devices for fault pfotection in the event ofa
with;
5(i), where exposed-
(i)
Regulation 531.2.2, taking into account the requirements
of Regulatiou
(ii)
conductive-parts are interconnected, or Regulation 531.2.3, taking into account the requirements
of Regulation 411.6.5(ii), where
411.6
exposed-
conductive-pafis are earthed in groups or individually'
InlTSystems,ifdisconnectionrequiredbyChapter4lintheeventofthesecondfaulttoearthcannotbeachieved used to provide the required fault protection within -o'. RCD'
by an overcurrent protective devici, on. o, the installation.
NOTE:
'hul1be
protective Refer.ence is also made to Regulation 419.3 where supplementary cases where automatic disconnection accotdil1g to Regu]ation
equipotcrtial bo[ding is reqllired in those
41L3 2 I cannot be achieved'
lor line-to-line voltage applications Overcunent protective devices used in IT systems shall have line poles suitable for operation in case of a second insulation and a neutrai pole, ilapplicable, suitable for the linelo-neutral voltage fault.
153
In IT systems, in the event of a second fault. the operation of the overcunent protective device shall result in the disconnection of all coresponding live conductors, including the neutral conductor, if any (see also Regulation 43
t.2.2).
531 .3
Residual current devices (RCDs)
531.3.1
General
Except where Regulation 53I.3. L201 applies, an RCD shall disconnect all live conducto$ olthe circuit protected. The protective conductor shall not pass through the sensor ofthe RCD except where this is unavoidable, e.g. in the case of armoured cables. In such exceptional cases, the protective conductor alone has to be passed again through the sensor but ir the reverse direction. The protective conductor shall be insulated and shall not be earthed either at the first or at the second passing through the sensor
A protective conductor current shall not contribute to the measurement ofthe residual current.
531.3.1.201 For protection against electric shock, there is no requirement to discomect/switch the neuhal in TT or TN systems. 531.3.1.202 It is not pennissible to irtroduce an extemal connection for the puryose of intentionally creating a residual curent to trip an RCD. NOTE 1: This does not preclude the use ofan RCD with
a
functional earth conneclion.
NOTE 2: This does not preclude the use ofa test instrument in accordance with part 6.
53'|,.3.2
Unwantedtripping
Residual curent protective devices shall be selected and erected such following shall be considered:
as
to limit the risk ofunwanted tripping. The
(i) subdivision ofcircuits with individual associated RCDs. RCDs shall be selected and the circuits subdivided in such a way that any eafih leakage current likely to occur during normal opemtion ofthe connected load
will not cause unwanted tuipping of the device. See also Section 314 (ii) in order to avoid unwanted tripping by protective conductor culrents and/or earth leakage cu[ents, the accumulation of such curents downstream of the RCD shall be not more than 30 % of the rated residual operating current
: NOTE 2: NOTE
(iii)
1
This will also allow a better selection of the g?e of RCDs according to the nature of the circuit or the load. RCDs may operate at any value ofresidual current in excess of50
oZ
ofthe mted residual current.
use of short time-delayed RCDs, provided the applicable requirements of Chapter
NOTE3:
4l
are met
ln the case oftransient effects,l pping ofthe RCD may occurby charging ofbypass capacitors orby other electromagnetic disturbances_
(iv) coordination of general type RCDs, selective type RCDs and time-delayed RCDs (cBRs according to BS EN 60947-2) as covered in Section 536 NOTE
4:
CBR is a circuit-breaker incorporating residual current protection.
(v) coordination olRCDs with surge protective deyices (SpD) according to Regulation 534.4.7.
531.3.3
Types of RGD
Different types ofRCD exist, depending on their behaviour in the presence ofDC components and frequencies. The appropriate RCD shall be selected from the following:
(i) RCD Type AC: RCD tdpping on altemating sinusoidal residual current, suddenly applied or smoothly increasing
(ii) RCD Type A: RCD tripping on altemating sinusoidal residual curent and on residual pulsating direct curent, suddenly applied or smoothly increasing. NOTE l: For RCD Type A, curent up to 6 mA.
t
pping is achieved for residual pulsating direct currents superimposed on a smooth direct
(iii) RCD Type F: RCD for which tripping is achieved
as
for Type A and in addition:
(a) for composite residual curents, whether suddenly apptied or slowly rising, intended for circuit supplied between line and neutral or line and earthed middle conductor
(b) for residual pulsating direct curents superimposed on smooth direct currenf.
154
l NoTE2:FoTRCDT}}eF.rippingisachievedlorresidualpulsatingdileclcu(ents;upenmposedonaSmoothdirect cunent uP to l0 mA. (iv) RCD Type B: RCD for rvhich tripping is achieved as for Type F and in addition:
(a) for residual sinusoidal altemating currents up to 1 kHz (b) for residual altemating currents superin.lposed on
a smooth
direct curent
(c) for residual pulsating direct currents superimposed on a smooth direct curent (d) for residual pulsating rectified direct curent which rcsults from two or more phases
(e)forresidualsmoothdilectcurents,whethersuddenlyappliedorslowlyincreased,independentof polarity. NoTE3:FolRCDTypeB,trippirlgisachievedfolresidualpulsating
l0
nr-A, whjchever is the hiShest value'
For general purposes, Type AC RCDS may be used NOTE 4: For guidance on the correct use ofRCDs for household and similar use'
see PD
IEC/TR 62350'
given in Annex A53' Figure A53 1' NOTE 5: Some typical fault curents in circuits cornprising semiconducto$ are
531.3.4
Selection according to the accessibility to the installation
persons, the RCDs In AC installations having RCDs that are intended to be operated by ordinary shall comply with:
531.3.4.1
BS EN 61008 series for RCCBS, or BS EN 61009 series for RCBOs, or
BS EN 62423 for Type F and Type B RCCBs and RCBOs protection. RCBO is a Residual RCCB is a Residual currcnt operated circuit-Breaker without integral overcunent :lh :rcuiFBrcaler u inlegral o\ ercLln cnl prolectlon Cunenr npcratcd ( an ordinary person. it shall be designed or installed so thar it is residual oper-ating current (11',) oI tirre dclay not possible to modify or adjust the setting or the calibration ofits rated inclication of in a or a tooi and a key without a clcliberatc act invol"ving the use ofcither
531.3.4.201 Where an RCD may be opcmted by n.eciranism its setting or calibration.
531.3.4.2 I[
'esulting
'isible
persors or skilled AC installations having RCDs that are intended to be opemted by instructed
persons, the RCDs shall con.rply with:
-
BS F.N 61008 scdes fot RCCBs. or BS EN 61009 series for RCBOs. or BS EN 62423 fol Type F and Type B RCCBs and RCBOs, or BS EN 60947-2 for CBRs and MRCDs
531.3.5
RCDs for fault Protection
531.3.5.1
General
Regulation 411 3' The use ofRCDs shall provide protection against faults in compliance with 531 3.5.2. 531.3.5 3 and 531 3 5 4), The selection ofRCDS depends on the type ofeafihing system (see Regulations the presence of DC componeuts and flequencies (Regulation 531 3 3)'
531.3.5.2
TN system
protected. The Iequilements for unwanted RCDS shall be installed at the origin of that paft ofthe installation to be tripping in accordance with Regulation 531.3.2 shall also be taken into account'
! ,
NoTE:Exceptwheleparticulalrestrictionforselectivityapplies,sevelalcircuitsn]aybeprotectedbythesamedevice' conductol shall take place at the supply The division of the PEN conductor into neutral conductol and protectiYe >ide
olthe RCDs.
On the load side
\n RCD
pemlitted' ofthe RCD, connection between the plotective and neufial conductors is not
shall not be used in a TN-C system.
531.3.5.3 TT system 531.3.5.3.1 LocationofRCDS RCDs shall be erected at the origin ofthat pafi of the installation to be protected. The requirements for unwanted tripping, in accordance with Regulation 531.3.2, shall also be taken into account.
NOTE: 531
Wrere there is more thafl one origin, this rcquirement applies to each origin.
.3.5.3.2
Selection of the rated residual operating current of the RCD
The rated residual operating curent value (16) of an RCD shall not exceed the Io" corresponding to the maximum value of the earth resistance RA to the exposed-conductive-parts, taking into account the possible seasonal variations, including soil lreezing and drying, ofthe part ofthe instaliation prote-cted by this device, as shown in Tabte 53.1.
Rt
is the sum of the resistances in ohms of the earth electode and the protectiye conductor connecting exposed-conductive-parts.
it to the
Table 53.1
- Correlation between the maximum value of earth resistance RAand the maximum rated residual operating current la.ofthe RCD
Maximum value of
RA
(O)
Maximum Id" of the RCD
2.5
204
5
10A
l0
5A 3A
t7 50
1A
100
500 mA
t6'7
300 mA
500
100 m,A
t667
30 mA
531'3'5'3.2.201 For Class I enclosures in TT systems where RCD protection is used on outgoing circuits, double or reinforced insulation ofatl live conductors (incoming cables, extension terminals, etc.y on ihe slupply sije ofthe incoming device, e.g. main switch, shall be used. Insulated and non-metallic sheathed cables are deemed to meet the requirements of double or reinforced insulation. NOTE 1; When selecting equipmeot, consideration should be given to the assembly manufacture/s intemal lile interconnecting
cable links on the supply side ofan RCD being insulated and non-metallic sheathed, or haviflg reinforced insulation or equivalelt mechanical protection.
NorE 2: only
the assembry manufacturer's approved intemal interconnecting cable rinks should be used.
531.3.5.4
lT system
531.3.5.4.1
General
In IT systems, protection of the neutral conductor by RCD Regulation 431.2.2 are fulfll1ed.
531'3'5'4'2
Case
of
interconnected
second
is permitted provided that the requirements of
fault on another live conductor when
exposed-conductive-parts are
where RCD' are used according to Regulation 411.6.3(v), one RCD per circuit shall be used. The operating characte stics of this RCD shall be selected according to Table 41 .1 of chapter 41.
531'3'5'4'3 interconnected
Case
of
second fault
on another live conductor when
exposed-conductive-parts
are not
Where, in an installation, alt exposed-conductive-parts are not interconnected, one RCD shall protect each group intercotutected exposed-conductive-pafi s.
of
The conditions for detemining the characteristics ofthe RCD shall be those for TT systems defined in Regulation 411.5:
-
156
The rated residual operating curent IAn has to be selected according to Table 53.1.
-
The disconnection time has to comply with the values given in Regulation J I 1.i.
I
In addition, fault protection for every circuit located downstream ofthis RCD shali be provided in accordance with the requircments of Regulation 411.6.3(v). [n this case every final circuit shal1 be indi\'idual)y protected by an RCD.
531.3.6
RCDs for additional protection
I
The use ofRCDs with a rated residual operating curert not exceeding 30 mA is recognized as additional protection in compliance with Regulation 415.1. These RCDs shall be provided to comply u ith the requir ements ofRegulation 411.3.3.
RCDs for additional protection in AC installations shall comply with:
-
BS EN 61008 series, or BS EN 61009 series. or BS EN 62423.
Where installed at the origin of a final circuit or a group offinal circuits, an RCD with a rated residual current not exceeding 30 mA may provide fault protection and additional protection simultaneously.
NOTE:
Consideration shall be given to the division ofthe installation (see Regulations 531.3.2 and 314.2).
DEVICES FOR PROTECTION AGAINST THE RISK OF FIRE
532
General
532.1
In locations where, in accordance with Chapter 42, a particular risk of fire exists, preventive protection measures against the risk of fire are required. This may also apply to other locations ofthe electrical installation, depending on a risk analysis.
NOTE:
A suitable evaluation ofthe risk should be carried out by one ormore persons competent
infue
sk assessments.
The selection ofprotective and monitoring devices shall take into account the nature ofthe load and the likelihood ofthe device to operate, e.g. fault curents ofhigher frequencies, DC fault currents or increased leakage curents. (See also Regulation 331.1.)
Residual current devices (RCDs) for protection against the risk of fire
532.2
RCDs shall comply with Regulations 531.3.1 to 53 1.3.4 and with the applicable requirements ofRegulation 531.3.5.
RCDs with a rated residual opelating curent not exceeding 300 mA shall be used. RCDs shall be installed at the origin ofthe circuit to be protected.
Residual current monitoring devices (RGMs) for protection against the risk of fire in lT systems
532.3
In lT systems, RCMs may be used as an altemative to RCDs in accordance with Regulation 532.2, provided that the location is supervised by one or more skilled or inshucted person(s). RCMs shall be in accordance with BS EN 62020 and operate in conjunction with switchgear suitable for isolation. RCMs shall be installed at the origin offinal circuits. The mted residual operating current shall not exceed 300 mA. Audible and visual signals shall be provided by the RCMs.
Insulation monitoring devices (lMDs) for protection against the risk of fire in lT systems
532.4
Insulation monitoring devices applied in
IT
systems for protection against the risk of fire shall comply with the
requirements of Section 538.
A fault location system in accordance with the requirement ofRegulation 538.2 able to locate the faulty circuit, may also he used.
s32.5
lnternal arc fault protection in a switchgear and controlgear assembly
I
Where required for special applications, intemal arc fault protection (e.g. optical detection system) detecting a fault arc together with a protection system can be selected in order to extinguish the arc.
Alternatively, an assembly with arc ignition protected zone(s) can be selected to minimise the risk ofan arcing fault. (Arcing class I in accordance with PD IEC/TR 61641.)
NOTE:
lntemal arc fault protection is typically associated \\ith a switchboard used in special applications. An asselnbly that 157
has been subject to an intemal arcing faul! can require maintenance or replacemeni.
532.6
Arc fault detection devices (AFDDs)
Where specified, arc fault detection devices shall be installed:
(i) (ii)
at the origin ofthe final circuits to be protected, and
in AC single-phase circuits not exceeding 230
V
AFDDs shall comply with BS EN 62606. Coordination ofAFDDs with overcurent protective devices, ifnecessary, shall take account ofthe manufacnuer''s instluctions.
533
DEVICES FOR PROTECTION AGAINST OVERCURRENT
533.1
General requirements
533.1.1
Compliance with standards
A device for protection against overcu[ent shall cornply with one or more ofthe following:
-
BS 88 series BS 646
BS 1362 BS 3036 BS EN 60898 series
BS EN 60947 series BS EN 61009
se
es
BS EN 62423.
The use ofanother device is not precluded provided that its time/cu[ent characteristics provide a level ofprotection not less than that given by the devices listed above.
The following protective devices shall be used only for protection against short-circuit currelrt:
-
instantaneous trip circuit-br eakers (lCB) in accordance with Annex O ofBS EN 60947-2
aM and aR type hnes in accordance with BS HD 60269-2 or BS HD 60269-3.
For evety fuse ard circuit-breaker there shall be provided on or adjacenl to it an indication of its intended mted cLlrrent as appropriate to the circuit it protects. For a semi-enclosed fuse, the intended ftrted cun'ent to be indicated is the value to be selected in accordance with Regulation 533.1.2.3.
533.1.2
Fuses
533.1.2.1 A fuse base shall be aranged so as to exclude the possibility of the fuse carier making contact between conductive pafis belonging to two adjacent fuse bases. A fuse base using screw-in flises shall be connected
so that the centre contact is connected to tlre conductor ftom the supply and the shell contact is connected to the conductor to the load.
533.1.2.2 Fuses having fuse links likely to be rernoved or replaced by an ordinary person shall be ol a type which complies withBs 88-3, BS 3036 or BS 1362. Such a fuse link shall either:
(i) (ii)
have marked on or adjacent to it an indication of the type of luse link intended to be used, or be of a type such that there is no possibility of inadvertent replacement by a fuse link having the intended rated curent but a higher fusing factor than that intended.
NOTE:
In polyphase systems additional measules may be needed, e.g. al all-pole switch on ihe supply side. in ordertoprevent thc risk of uDintentional contact with live par.ts on the load side.
Fuses or combination units having fuse links likely to be removed and replaced only by skilled or irstructed person(s) shall be installed in such a manner that the fuse links can be removed or replaced without unintentional contact with live pafis. 533.1 .2.3 A fuse shall prefembly be of the cartridge type. Where a serri-enclosed fuse is selected, it shall be fitted with an element in accordance with the manufacturer's instructions. if any. In the absence of such instrucnons,
158
.-
it shall
be fitted with a single element of tinned copper wire of the appropriare diamerer specified in Table 533.1.
TABLE 533.1
-
Sizes of tinned copper wire for use in semi-enclosed fuses
Rated cunent offuse element (A)
Nominal diameter of \1ire (mn) 0.15
533.1.3
5
0.2
10
0.35
I5
0.i
2C)
0.6
25
0.75
30
0.85
45
1.25
60
1.53
EO
1.8
100
2.0
Circuit-breakers
Where a circuit-breaker may be operated by an ordinary person, it shall be designed or installed so that it is not possible to modif, the setting or the calibration ofits overcurrent release without a deliberate act involviue the use ofeither a key or a tool and resulting in a visible indication ofits setting or calibration. Where a screw-in type circuit-breaker is used in a fuse base, the requirements ofRegulation 533.1.2.1 also apply.
According to the requirements ofAnnex H of BS EN 60947-2, devices marked with the voltage value followed by the :1 mbol ffi .hall nor be uced in lT 5) slems lor such r oltage. \a_y
533.2 533.2.1
Selection of devices for overload protection of wiring systems
The rated curent (or cufient setting) of the protective device shall be chosen in accordance with Regulation 433.1.
In certain
cases,
to avoid unintentional opemtion, the peak current values of the loads may have to be taken ilrto
consideration.
In the case of
a cyclic load, the values of I. and I2 shall be chosen on the basis ofvalues ofl6 and I. for the thermally equivalent constant load
where:
16
is the curent for which the circuit is designed
I.
current-catrying capacity of a cable for continuous service under the particular installation conditions concemed
I, Ir
is the mted curent or cu[ent setting ofthe protective deyice
NOTE:
Additional requirements for protection against overload when harmonic currents are present
When selecting an overload protective device to comply with Regulation 433. curents in accordance with Regulation 431.2.3.
NOTE:
I
The current causing effective operation in the conventional time of protective dcvices may also bc naned It (for circuit-bteakers) or If (for fuSes) according to the product standards. Both It and Il are lnultiples of ln and attention should be given to the correct representation ofvalues and indexes.
533,2,2
533.3
I
is the curent causing effective operation ofthe overload protective device within the conventional time as ,tared in the producr standard.
See also Appendix 4
l, account shall
be taken of hamonic
for fudher details on harmonics.
Selection of devices for protection of wiring systems against fault current
The application of the regulations of Chapter ,13 shall take into account both the minin.nn and maximum lault current conditions, so ftat the highest energt let-rl'trough is taken itto accounr.
I I
159
Where the standard covering a protective device specifies both a rated seruice short-circuit breaking capacity and a rated ultimate short-circuit bleaking capacity, it is acceptable to select the protective device on the basis of the ultimate short-circuit breaking capacity lor the maximum fault curent conditions. Operational circumstances may, however, make it desimble to select the protective device on the seryice shoft-circuit breaking capacity, e.g. where a protective device is placed at the origin ofthe installation.
Where the short-circuit breaking capacity of the protective device is lower than the maximum prospective shortcircuit or eath fault curent that is expected at its point olinstallation, it is necessary to comply with the requirements ofthe last paragraph ofRegulation 536.1 and Regulation 536.5.
NOTE:
To calculate the maximurn and mhimum faull cunents, see Technical Report PD CLC/TR 50480 'Determination cross-sectional area of conductors and selection ofprotective devices'. See also Appendix 4, paragraph 2.5.
534
of
DEVICES FOR PROTECTION AGAINST OVERVOLTAGE
For furher information see Appendix 16.
534.1
General
This section contains provisions for the application olvoltage limitation in order to obtain insulation coordination in the cases described in Section 443, BS EN 60664-1, BS EN 62305 series and BS EN 61643 series. This section focuses mainly on the requirements lor the selection and erection of SPDs for protection against transient ovenoltages where required by Section 443, the BS EN 62305 series, or as otherwise stated. BS EN 62305-4 and BS EN 61643-12 series deal with the protection against the effects ofdirect lightning stokes ol stuokes near to the supply system. Both documents desc be the selection and the application of suge protective
devices (SPDs) according to the Lightning Protection Zones (LPZ) concept. The LPZ concept descrii,es the installation ofType 1, Type 2 and Type 3 SPDs. See Figr"rre 534.1 .
Fig 534.1
-
Lightning Protection Zones (LPZ) concept Cable for data transmission
Low voliage electr cal
I\,4ast
supply-cable
or
railing
LPZ2
rm ffi Critical equipment
Metallic water pipe
[.4etallic gas pipe
feZ
!
SeO ut
(D
SPD at LPz 1/2 for overvoltage protection
Olt for lightning current protection
@ toExtraneous-conductive-part main earthing terminal
connected
. Boundary of LPZ
1 is an external Lightning Protection System (LPS)
..
'160
Boundary of LPZ 2 is a screened room to reduce ihe effects of electromagnetic interference (El\,41)
NOTE
l:
SPDs with more than one
lype ofclassification are available, e.g. combined Tlle
l l
or combined Type 2+3.
Section 534 does not take into account:
-
suge protective components incorporated in appliances connected to the installation portable surge protective devices (SPD).
NOTE 2: Further infomation can be found in DD CLC/TS 61643-12. Section 534 applies toAC power circuits. As far as it is applicable, the requirements ofSection 534 may be followed for DC power circuits. NOTE 3: Overvoltages ofatmospheric origin and electrical switching events can affect metallic data. signal and telecommunication ljnes. Protection measures for these systems are detailed within PD CLC/TS 61643-22.
Nof used
534.2
Not used
534.3
534.4
Selection and erection of SPDs
534.4.1
SPD types and location
534.4.1.1
(i) (ii)
Where SPDs are required:
SPDs installed at the origin ofthe electrical installation shall be Type 1 or Tlpe 2
installed close to sensitive equipment to further protect against switching transients originating the building shalt be Type 2 or Type 3.
SPDS
NOTE:
within
equipotential bonding SPDs and are fltted atthe origin ofthe electrical installation to specifically prevent danger-ous sparking which could lead to fire or electric shock hazards. In accordance with BS EN 62305-4, a lightning protection system which only employs equipotential bonding SPDS provides no effective protection against failure of sensitive electrical and electonic systems. Further SPDS (TWe 2 and Type 3) are required to protect sensitive and critical equipment (for example, hospital equipment and fire/secu ty alarm systems) Type
1 SPDS are
downstream
offen referred to
as
ofthe origin ofthe electrical installation.
534.4-1.2 In accordance with the LPZ concept, where installed to preserue the zone integrity.
a
cable crosses the zonal interface, further SPDs shall be
534.4.1.3
where the installation of SPDs is required by Section 443 and the sfixcture is equipped with an extemal lightning protection system or protection against the effects of direct lightning, Type 1 SPDs shall be installed as close as possible to the odgin ofthe electrical installation.
534.4.1.4 Where the installation ofSPDs is required by Section 443 and the structure is not equipped with an extemal lightning protectiofl system or does not require protection against the effects of direct lightning, Type 2 SPDs shall be installed as close as possible to the origin ofthe electrical installation. 534.4.1.5 Type 2 or Type 3 SPDs sha1l be located in the fixed electrical installation, for example, in subdist bution boards or close to the equipment to be protected, to achieve the required voltage protection level; see Figure 534.2. These SPDs shall be coordinated with Type I and/or Type 2 SPDs being installed at the origin ofthe electrical installation (see Regulation 534.4.4.5).
-,"\
f^'"i
uRY E fl Io '***
161
ryry T Fig 534.2
-
Example of insta ation of Type 1, Type 2 and Type 3 SpDs
Type 1 SPD and/or Type 2 SPD
Type 2 SPD
Type 2 SPD
or
or Type 3 SPD
Type 3 SPD
534.4.1.6 Consideration shall be given to the provision of SPDs to protect from other sowces, such as: (i) switching ovewoltages produced by curent-using equipment rocated withir the installation (ii) ovel'voltages on other incoming services such as metallic telecommunication and signalling services (iii) overwoltages on other seryices feeding other structures such as secondary buildings, extemal installations/lighting, power lines feeding extemal sensors.
These SPDs shall be installed and located as close as possible to the origin of such events. NOTE: For fufther inl-omation see BS EN 61643-12 series and BS EN 62305_4.
534'4'1 '7 The presence of SPDs installed downstream of a distribution board (e.g. in a socket-outlet) shall be permanently indicated (e.g. by a label) at or near the distdbution board. 534.4.2
Connection modes of SPDs
Protection against transient overvoltages shall be provided: - between live conductors and pE (common mode protection), and,/or between live conductors (differential mode protection). NOTE;
For further infomation see DD CLC/TS 61643-12.
534.4.3
Connection types
534.4.3.1 Connection Connection Type
-
Type CT1
CTI (e.g. 4+0 configumtion):
SPD assembly providing a mode ofprotection between each live conductor (line and neutral conductors, availablet and PE.
An example ofconnection Type
162
crl
for application in a three-phase system is given in Figure 534.3.
if
Fig 534.3
-
Connection Type CT1 (4+0-configuration) for a three+hase system with neutral
Ll
534.4.3.2 Connection
L2
L3
N
Type CT2
Connection T1.pe CT2 (e.9. 3+ 1-configuration):
-
SPD assembly providing a mode ofprotection between each line conductor and the neutral conductor, and between the neutral conductor and PE.
An example ofconnection Type CT2 for application in
Fig 534.4
-
a three-phase system is
given in Figure 534.4.
Connection Type CT2 (e.9. 3+1-configuration) for a three-phase system with neutral
L1
L2
L3
N
I
I 534.4.4
Selection of SPDS
534.4.4.1 General The following parameters shall be considered for SPD protection:
-
voltage protection level (Un) ofthe SPD and rated impulse withstand yoltage (U'v) ofthe equipment to be protected (see Regulation 534.4.4.2)
-
continuous operating voltage (U.) ofthe SPD, i.e. supply system
nominal
discharge current (I".16) and/or impulse discharge
curent
(T! (Ii,,p)
TN, IT) (see Regulatior 534.4.4.3)
ofthe SPD
(see
Regulation 534.4.4.4)
SPD coordination (see Regulation 534.4.4.5) expected shofi-circuit current (Isccn). (see Regulation 534.4.4.6)
follow curent interrupt mting (Ifi) (SPDs shall comply with the requirements ofBS EN 61643-11).
NOTE:
Additional information rcgarding selection and application is given inDD CLC/TS 61643-12.AnnexD of DD CLC/ TS 61643-12 provides application examples ofselecting SPDS.
534.4.4.2 Selection with regard to voltage protection level
(Up)
The voltage protection level (Up) of SPDs shall be selected in accordance with impulse withstand voltage Category II ofTable 443.2 and in no case exceed the required rated impulse voltage ofthe equipment. NOTE 1: In some cases, for example where the continuous opeEtion of the equipment is c tical, the voltage protection level (Up) of SPDS can be selected to be lower than the impulse immunity of equipment. The impulse immunity voltage of equipment is lower than the impulse withstand of equipment and requires SPDs with lower voltage protectioo level Up between live conductors (e.g. line to neutral) to avoid equipment malfunction, particularly against switching transients. For further information see DD CLC/TS 61643-12.
In installations operatrtg at 230/400V, the voltage protection level ofthe instaltecl SPD assembly shall not exceed 2.5 kV, as the SPD's connecting leads have additional inductive voltage drop across them (see Regulation 534.4.8). It may, therefore, be necessary to select an SPD with a lower voltage protection level.
Ifthe distance between the SPD
and equipment to be protected (protective distance) is greater than l0 m, oscillations could lead to a voltage at the equipment terminals ofup to twice the SPD'S voltage protection level. Consideration shall be given to the provision of additional coordinated SPDs, closer to the equipment, or the selection of SpDs with a lower voltage protection level.
NOTE 2: It is recommended that the voltage protection level provided by SPDS does not exceed
a safety margin of 80 % ofthe required rated impulse voltage for equipment according to Table 443.2 and conesponding to overvoltage category Il.
This safety margin is not necessary where one ofthe foltowing cases applies:
-
where the equipment is connected directly to the SpD terminals a protection scheme according to Figure 534.9 is already applied where the voltage drop across the overcuaeflt protection in the SPD branch circuit is already taken into account for the voltage protection level Up
where
where protection accordi[g to overvoltage category equipmenl is installed at this locatio[.
II
is provided but only over.r'oltage category
III or IV
NOTE 3: DD CLC/TS 61643-12 gives additional infomalion about the mted impulse voltage of equipment and the given Up for rhe SPD. Tqble 534.1 Not used
534.4.4.3 Selection of SPDS with regard to continuous operating voltage
(Uc)
In AC installations, the maximum continuous operating voltage Uc ofSPDs shalt be equal to or higher than required
by Table 534.2.
Table 534.2
-
Minimum required uc of the sPD dependent on the supply system configuration
SPD connected bctween (as applicable)
Line conductor and neutral conductor
Line conductor and PE conductor
System configuration of distribution network
TN system
TT system
lT system
l.1u
1.1 U
.i3
i3
!3
or (0.64 x U)
or (0.64 x U)
or (0.64 x U)
1.1 U
1.1U
r/:
ri:
or (0.64 x U)
or (0.64 x U)
U
U
1.1U
J":
.i,3
.i3
1.1
U
1.1
Neutral and PE conductor
U
or (0.64 x U)
Line conductors
NOTE: a These
1.1U
1.1U
values are related to worst-case fault conditions, therefore, the tolerance of 10 account.
164
1.1U
U is the lineto-line voltage ofthe low voltage system. o/o
is not taken into
impurse discharse of spDs with resard to discharse currenr (r*oa) and
*rr_ection
T
Atolneartheoriginoftheelectricalinstallation,SPDsshallcomplywithoneofthefollorvingcases.asapplicable: -wherethebuildingisprotectedagainstdilectlightningstrike,SPDsattheoriginoftheelectricalinstallation 4 4 4 2 and Table 534 4 shall be selected according to Regulation 534 Regulatiot 534 4 4 4 in other cases, SPDs shall be selected according to
l'
also comply with the near the oligin ofthe electrical installation shall spDs installed downsfeam ofthe sPDs at oI 4'5 ' coordination requirements in Regulation 534 4
NorE:overvoltagesduetoswitchingcanbelorgerindurationandcancontainmoreenergythanthetransientovervoltages discharge cuaent for the selection of SPDS with regard to nominal origin. fnl, fri. io U. of atmosphe c
"oniidered
and impulse discharge cunent For tufiher
534.4.4.4.1
infomation
see
DD CLC/TS 61643-12'
TlPe 2 SPDs
WhereType2SPDsarerequiredatornealtheodginoftheelecfficalinstallation,theilnominaldischargecurrent (In.pa) shall be not less than that given in Table 534 3'
Table534'3-Nominaldischargecurrent(l""pd)dependingonsupplySystem and connection TYPe
534.4.4.4.2
I
Type
I
SPDs
WhereTypelsPDsalelequiledatorneartheoriginoftheelectricaliastallation,oneofthefollowingcasesapplies: (i)WherenoriskanalysisaccordingtoBsEN62305-2hasbeencarriedout'theimpulsedischargecurrent (Ii,,p) shall be not less than as given in'fable 534 4' Table 534.4
-
the building is protected Selection of impulse discharge-current (li.J where against direct lightning strike
I NOTE
-
Tht.
"b1"
r"f".,.
t€htning prot""tion]t"1t
(L!LI]lg:g IV
be€n caried out' the impulse discharge current (ii) Where the risk analysis according to BS Ef,61i91^1lis {1,,"!l shall be detennined according to the BS
E\
02105 series'
534.4.4.5 Coordination of two or more SPDs the manufacturer's provide coordination in operation by reference to SpDs shall be selected and erected such as to data.
current rating 534.4.4.6 Selection of SPDs with regard to the short-circuit SPD' ln general, the short-circuit curent rcting I56sa ofan
by the manufacturer' shall not be lower than the points oi the SPD assemblv; sei Figure 534 5'
as stated
itr. maximum prospective short-circuit Ju-nlni'ui "onn"",ion
(lsccR)
NOTE 1: The SPD alone, of as an assembly in conjunction with its discoturector and,/ol overcurenl protective device (OCpD), is required to withstand the short-circuit curent raling ISCCR as stated by the manufacturer. This value is defined and tested according to BS EN 61643-l l, in coajunction with the discorutector and_/or OCPD as statedby the marlufacturer. NOTE 2: This requirement does not apply to SPDS connected between the neutral conductor and PE in TN or TT systems, fbr which this is already covered by the product standard BS EN 61643-l l.
For SPDs connected between the neutral conductor and PE in IT systems, the shofi-circuit current rating I"ccn ofthe SPD shall not be lower than the maximum prospective short-circuit current at the connection points oithis SpD in case ofa second fault.
534.4,4.7 Selection of SPDS with
regard to the follow current interrupt rating (h)
In general, the follow current interrupt rating Ifi ofthe SPD, ifdeclared by the manufacturer, shall not be lower than the maximum prospective short-circuit curent at the connection points ofthe SPD assembly. See Figure 534.5. For SPDS connected between the neutral conductor aIId PE in IT systems, the follow cuffent interupt rating 16 ofthe SPD, ifdeclared by the manufacturer, shall not be lower than the maximum prospective short-circuit current at the connection points ofthis SPD in case ofa second fault.
Fig 534.5
-
Connection points of an SPD assembly
Key OCPD
1
overcu[ent protective device in the installation
OCPD 2
overcurrent protective device specified by the SPD manufacturer
SPD
surge protective device
SPDA
SPD assembly
A&B
connection points of SPD assembly
EIT
equipment or installation to be protected.
534.4.5
Protection of the SPD against overcurrent
534.4.5.1
General
SPD installations shall be protected against overcurent with respect to shorGcircuit curents.
This protection may be intemal and/or extemal to the SPD according to the manufacturer's instructions. The ratings and chamcteristics ofextemal OCPDs for protecting the SPD assembly sha11 be selccted in accordance a high surge curert capability for the complete assembly whilst not exceeding the rutings and charactedstics as required in the SPD manufacturer's installation instructions for the maximum overcurrent protection.
with Section 434 and be the highest permissible rating to provide
166
534.4.5.2 Arrangement of SPDs with relation to overcurrent protection case of OCPD opemtion a sing from SPD failure, the continuit) of dre supph ro dre equipment is unaffected. However, neither the installation nor the equipment is protected against pos:ible tunher over.,,oltages (see Figule 534.6). Il such an a[angement, the effective voltage protection ler el u ithin the insrallation is increased due to the additional voltage drop at the extemal OCPD connected in series s ith the SPD.
In
Fig 534.6
-
Example of overcurrent protection in the SPD branch by using a dedicated external overcurrent protective device
K"y overcurent protective device specified by the
OCPD
SPD manufacturel
suge protective device
SPD
SPDA
SPD assembly
A&B
connection points of SPD assembly
Efi
equipment or installation to be protected.
534.4.5.3 SelectivitybetweenOCPDs Where selectivity between OCPDs is necessary to prevent danger and where required for proper functioning ofthe installation, the manufacturer's instructions shall be taken into accounl see Regulation 536.4.
534.4.6
Faultprotection
Fault protection, as defined in Chapter SPD failure.
4l,
shall remain effective in the protected installation even in the event
of
In the case of automatic disconnectlon of supply:
in TN Figure
systems, this may generally be fulfilled by the OCPD on the supply side of the SPD l6.4l olAppendix 16);
(See
in TT systems, this may be fulfilled by:
(a) the installation ofSPDs downstream (load side) ofan RCD (See Figure 1642 ofAppendix 16), or (b) the installation ofSPDs upstream (supply side) ofthe main RCD. Owing to the possibility ofa failure of an SPD connected between neufual conductor and PE, the conditions ofRegulation 411.4.1 shall be met and the SPDs shall be installed in accordance with connection Type CT2 (See Figure I 6.43 ofAppendlr I 6). in IT systems, no additional neasure is needed (See Figure 16A4 ofAppendix 16).
Table 534.5
-
Connection of the SPD dependent on supply system
Supply system at the connection point ofthe SPD assembly
Connection Type
CTI
CT2
TN svstem
Y
Y
TT system
SPD only downstream ofRCD
Y
Y
N/A
IT system with neutral IT system without neutral NOTE 1:Y: applicable NOTE 2: N/A: not applicable
NOTE;
Additional requirements rnight apply for SPDs installed in the area of influence of applications such as railway systems, HV power systems, mobile units, etc.
534.4.7
SPD installation in conjunction with RCDS
Where SPDs are installed in accordance with Regulation 534.4.1 and are on the load side of an RCD, an RCD having an immunity to surge curents ofat least 3 kA 8/20 shall be used. NOTE 1: Type
S
RCDs in accordance with BS EN 61008-1 and BS EN 61009-l satisly this requirement.
Installation ofTlpe 1 SPDs downstream ofan RCD is not reconmended. NOTE 2:
Ir
the case of a surge curent higher than 3
534.4.8
liA 8/20. the RCD may trip causing interruption ofthe supply.
Connection of SPDs
All conductors and interconnections to the relevant line to be protected, together with the connections between the SPD and any extemal OCPD, shall be kept as shorl and as straight as possible and any unnecessary cable loops shall be avoided.
The length ofthe connecting conductors is defined as the sum ofthe path length ofconductors used from the live conductor 10 the PE in between connection points A and B as shown in Figure 534.8 (for example, a + b + c).
Fig 531.7 Not used
168
Fig 534.8
-
Connection of the SPD
A
Live conductor
Key OCPD
overculTent protective device
SPD
surge protective device
PE conduqtor
protective earthing conductor
A and B
conlection points of SPD assembly.
NOTE:
When the OCPD is not present, lergth b is cqual to 0.
Consideration shall be given to limit the total wiring length of conductors between connection points of the SPD assembly, which should preferably not exceed 0.5 m and in no case exceed 1.0 m. To meet these requirements, the main protective conductor shall be connected to the eafihing terminal located as near as possible to the SPD by adding, if necessary, an intermediate earthing teminal (see Figure 534.9).
To determine the total lergth of the connecting conductors according to Figure 534.9, the lollowing conductor rensths shall not be taken into account: between the main eathing terminal and the intermediate earthing terminal
I
between the intermediate earthing terminal and the PE conductor. The length (and therefore inductance) ofthe conductors betweer the SPDs and the main earthing teminal shall be i.pt to a minimum. SPDS may be connected to the main eadhing tenninal or to the protective conductor via metallic rafts. e.g. the metallic enclosures ofthe assembly (see Regulation 534.4.2), provided it is connected to PE and meets --:r- requirements for a protective conductor in accordance with Chapter 54. Connection ofthe rclevant SPD(s) to the :.ain earthing teminal, and in addition to the main protective conductor, may inprove the voltage protection level.
: ihe total wiring length (a +b +c) as defined in Figure 534.8 exceeds 0.5 m, at least one of the following options
':all
be chosen:
select an SPD with a lower voltage protection level U, (a I m length of rectilinear conductor carrying a discharge curent of 10 kA (8/20) adds a voltage drop ofabout I 000 V)
install a second coordinated SPD ctose to the equipment to be protected so as to adapt the voltage protection level U! to the rated impulse voltage ofthe equipment to be protected rse the installation method as shown in Fisure 53,1.9.
169
Fig 534.9
-
Example of installation of an SPD in order to decrease lead length
of SPD supply conductors
Key OCPD
overcurrent protective device
SPD
surge protective device
PE conductor
protective earthing
Elt
equipment/installation to be protected
1
main earthing terminal
2
intemediate
3
length c (to be considered)
4
cable lengh need not be considered
5
cable length need not be considered
AandB
connection points of SPD assembly.
NOTE:
eaft
hing terminal
For further irfomation see DD CLC/TS 6l643-12.
534.4.9
Not ttsed
534.4.10 Connecting conductors of SPDs Conductors between SPDS and the main earthing terminal or the protective conductor shall have a cross-sectional area not less than:
-
6
mrf
copper or equivalent for Tlpe 2 SPDs installed at or near the origin of the installation
16mm2 copper or equivalent for Type
I
SPDs installed at or near the odgin
ofthe installation.
Referring to Regulation 433.3.1(ii), conductoN connecting SPDS and the OCPDs to live conductors shall be rated to withstand the prospective shod-circuit current to be expected and shall have a cross-sectional area not less than:
-
l.
2.5 mm2 copper or equivalent for Type 2 SPDs installed at or near the origin ofthe installation 6 mm': copper or equivalent for Type 1 SPDS installed at or near the origin
ofthe installation.
DEVICES FOR PROTECTION AGAINST UNDERVOLTAGE
535
comply with the relevant requirements ol Section'l-15' Devices for protection against undervoltage shall for protection against undervoltage mal- be required' For protection ofpeEons and propedy, devices are selected as follows: Protective devices against undenoltage (i) direct operating undervoltage release:
Iower value ofthe relay operating voltage
higher value ofthe relay operating voltage
-
time delaY (ifrequired)
(i,) indirect opemting undervoltage release: - lower value ofthe operating voltage higher value ofthe opemting voltage
-
time delaY (ifrequired)
(ii0 automatic reclosing when the voltage is restored: with reclosing Prevention without reclosing Prevention'
Thecharacteristicsoftheprotectivedevicesagainstundervoltage-shallbecoordinatedwiththerequifementsinthe offof the electrical equipment' (in:rurrl relevant standards for switching on
"r'."*l
op*u,lon aid switching
FOR PROTECTION' ISOLATION' CO-ORDINATION OF ELECTRICAL EQUIPMENT SWITCHING AND GONTROL
536
536.1
General
hissectiolcovelsco-ordinationinthecascofafaultandoverloadconditionsandalsotakesintoconsideration as follows;
l"i..ti".
..p..it
L3
deviccs relevant to the co-ordination of electrical
-
overculTcl.It protcctive device (OCPD) (CPS) control and protective switching device
-
residual curent device (RCD) contactor and starter
switch and disconnector'
\OTE 1: Co-ordination ofmonitoring
devices is undel considemtion
\oTE2:Referencetothemeaningof.someoftheabbreviationsusedinthissectionmaybefoundinTableA53,linArrnexA53 located at the end ofthis chapter' but provides requirements the selection ofan electrical device alone' ' :'j,,:" -::.n 536 does not provide requireurents lor them'
co-ordilation between selection ofelectrical devices to achieve electrical
.
squilell]entsalsocoveraspectsofcontinuityofsupplyoftheinstallation'
:.:6.2 \: -E:
:::3
provided Electrical devices considered and function Table
by different electrical devices' A53.I in Arnex A53 sho$'s the functions provided
Co-ordination requirements
j , ..:.i.iing electrical devices as covered by the following regulations, the mutual interaction ofthe installation' ,- -:. .hail be considered so that they do not adversely affect the safety -: - -.rrdilation ofelectrical
-
devices considers requiretnents in case
between those
ol
short-circuit
olerload residual curents :..r' co-oldinatiol oielectrical devices are:
-
selectivity short-circuit Protection o\ erload Protectioll. 1-',
Electrical devices shall be selected taking into account the co-ordination characteristics
as
givenby the
m anu
facturers.
536.4 Requirementsforselectivity 536.4.1 General Selectivity between OCPDs is defined in Regulation 536.4.1.2 for overload conditions and in Regulation 536.4.1.3 for short-circuit conditions. Selectivity between RCDS is defined in Regulation 536.4.1.4 and selectivity between OCPD and RCD is defined in Regulation 536.4.1.5.
In this regulation, the OCPD could be replaced by an SCPD.
536.4.1.2 Selectivity under overload conditions between
OCPDs
536.4.1.2.1 General requirements Where selectivity is required, as shown in Figure 536.1, the design shall be verified either by:
-
desk study, taking into account the relevant product standards and the manufacturer's literature, or appropriate software tools where inlormation is provided by the manufacturer for this specific use, or tests in accordance with the applicable product standard (in order to achieve the corect test performances and reproducibility), or
manufacturer's declaration.
In the case of a desk study, when time/current characteristics are used to veriry selectivity, account shall be taken of the reference ambient temperature for which the tdpping curves are given and to load conditions before the overcurTent.
Fig 536.1
-
Selectivity between OCPDs
o c P D 1
o C P D 21
536.4.1.3 Selectivity
o c P D
22
under short-circuit conditions between OCPDs
536,4,1.3.1 General requirements Where selectivity is required (see Figure 536.1), verification shall be made either by:
-
desk study, taking into account the releyant product standard and the manufactuer's literature, or appropriate software tools where information is provided by the manufacturer for this specific use, or tests in accordance with the applicable product standard (in order to achieve the
and reproducibility), or
-
manufacturer's declaration.
co[ect test perlormances
In the case ofa desk study, when energy limitation curves are used to voltage for which the curves are given.
verif
selectiviry. account shall be taken ofthe
cases given in .{53.7 and 453.10 in Annex A53, selectivity will be obtained for shot-circuit currents up to a specific value, the selectivity limit current. The value ofthis limit wili be given by the manufacturer In a pafiicular installation selectivity may be total or partial.
In
NOTE:
Generally, manufacturers provide tables giving information on selectivity in case of short-c ircuit.
536.4.1.4 SelectivitybetweenRCDS (i) General requirements Where selectivity is required (see Figure 536.2), verification shall be made either by: desk study, taking into account the relevant product standard and the manufacturer's literatue, or appropriate software tools where information is provided by the manufacturer for this specific use, or tests in accordance with the applicable product standard (in order to achieve the correct test performances and reproducibility), or
manufactwer's declaration. NOTE 1: Generally, manufactuers provide information specifying selectivity between RCDS.
(ii) Selectivity in
case of residual currents
Selectivity in case ofresidual currents, as shown in Figure 536.2, is given under the following conditions: the upsheam RCD is ofselective type (type S or time-delayed type with appropriate time delay setting), and
the mtio of the rated residual operating current of the upstream RCD to that of the downstream RCD is at least 3:1,
In the case of RCDs with adjustable rated residual operating current and time delay, reference shall be made to rnanufaclurer's in:.tructions lor selectivity.
NOTE2: RCD type
S is
in accordance with BS EN 61008 se esorBSEN61009series.
NOTE 3: A time-delay iype RCD ir accordance with BS EN 60947-2. Annex B or Annex M will be marked rvith thc symbol At followed by the limiting non-actuating time in 1rrs or markcd with an [S]
Fig 536.2
I
NOTE
4:
-
Selectivity between RCDS in case of residual current
RCD1 is type S or time-delayed type.
536.4.1.5 Selectivity between OCPDs and RCDs 536.4.1
.5.1 Selectivity between RCD(s) and upstream OCPD
the event of an earth fault, cuaent may reach a high value that could exceed the rnstantaneous tdpping current and upstrea[r OCPD is required, an RCBO or - BR shall be used and the requirements of selectivity according to Regulation 536..1.1 .2 shall be applied.
r
:irhe upstream OCPD. Therefore, when selectivity between RCD(s)
L
173
Fig 536.3
-
Selectivity between OCPD and RCD using RCBOS
o c D 1
R
R
c
c
B
a
o
o
21
22
In Figure 536.3, ifRCCBs are used instead ofRCBOs, selectivity cannot be guaranteed. In this case, ifthere are OCPDs downstrcam olthe RCCB, as shown in Figure 536.4, selectivity may be achieved provided that the requirements ofRegulation 536,4.1.2 and Regulation 536.4.1.3 are fulfilled. In addition, the connection between the RCCB and the downstream OCPD shall be selected and erected so as to minimize the risk of earth faults.
NOTE:
ln orderto minimize the risk offaults between RCCB and downstream OCPD, specific wir-ing accessories may be used (e.g. .pecifi c bu.bars).
Fig 536.4
-
Selectivity between OCPD and RCD using RCCBs
o C D 1
R
c
c
c
C
B 21
536.4.1.6 Selectivity
B
22
o
o
o
C
C
C
D
D
D
31
32
between RCDs and downstream OCPDs
In the event of an earth fault, the earth fault curent may be lower than the instantaneous tuipping cunent of the downstream OCPD. In this case, the upstream RCD will tlip and selectivity may not be achieved. Thereforc, when selectivity between RCDs and downstream OCPD is required, RCBOs shall be used and selectivity requirements according to Regulation 536.4.1.4 shall be applied.
Fig 536.5
-
Selectivity between upstream RCCB and RCBOs
R
c c B
I
R C B
NOTE:
RCCB
1
R C B
o
o
21
22
is type S or time-delay type.
536,4.2
Requirements for protection in case of short-circuit
536,4,2,1
Combined short-circuit protection of OCPDS
In this regulation, the OCPD could be replaced by an SCPD.
This breaking technique allows the use of short-circuit protective devices with a lower breaking capacity than required in Chapter 43. It is only applicable to short-circuit protective devices.
Fig 536.6
-
Typical configuration for combined short-circuit protection of OCPDs
o c P D 1
o c P D
2
irc _.31',1
'' ::l'lts
Regulation 434.5.1 permits a device with a lower rated breaking capacity than the prospectiYe short-circuit curent at its point of installation to be used in specific conditions. When selecting two OCPDs for combined shod-circuit protection, reference shall be made ro rhe instmctions ofthe manufacturer of the downsheam OCPD. These instructions are derived from tests peribrmed according to relelant product standards, as applicable (e.g. BS EN 60947-2 andBS EN 60898-1). Where no iribrmatior is available from the manufactruer, combined shofi-circuit protection of OCPDs shall not be used. and each OCPD shall har'e the
required short-circuit capabilily at the point ofinstallation.
Ifdeclared by the manufacturer ofboth devices, the combined short-circuit capability ofOCPDl and OCPD2 may be higher than the breaking capacity of either OCPD. In this case, the connection between the two devices has to minimize the risk of short-circuits and there shall not be any shofi-circuit contdbutions by other active equipment in parallel to oCPD1. NOTE
1
: Co-ordination of an OCPD with a separate curent limiter to increase the shon-circuit breaking capacil), of arl OCPD may be used according to the manufactuer's instructions.
NOTE 2: Combined short-circuit protection may be used for manual motor stafier having a short-circuit capabilit\, ifl combination with OCPD. when declared in the manufacturer documentation.
536.4.2.2 Back-up protection of contactors
or overload relays
In this regulation, the OCPD could be replaced by an SCPD. Contactors complying with BS EN 60947-4-1 or BS EN 61095 do not provide protection against short-circuit, thus they shall be protected by an upstream overcurent protective device (OCPD). NOTE 1: Contlol and Protective Switching Devices (CPS) provide protection against short-circuir. and therefore provide
intinsic co-ordination. Figure 536.7 gives
a
typical schematic for co-ordination ofa contactor with
Fig 536.7
-
a
short-circuit protective device (OCPD).
Co-ordination between OCPD and contactor in case of short-circuit
Regutation 512.1.2 requires equipment to be selected for the design current which it has to carry in normal service and the current likely to flow in abnormal conditions. In the event of shofi-circuit, the let-through energy and the peak culTent may cause the contactor to open its contacts at a level of current beyond its making and breaking capacity. Co-ordination ofthe contactor and the OCPD is needed to achieve safe operation in case ofshot-circuit. Co-ordination between a contactor and an OCPD is verified by mandatory shod-circuit tests according to BS EN 60947-4-1or to BS EN 61095, as applicable. Contactors shall be selected and erected in conjunction with the shorl-circuit protective device declared by the manufactwer, such that the rated conditional shofi-circuit current is higher than the plospective short-circuit current at the point ofinstallation. The rated conditional shot-circuit curent can only be obtained by type-testing and thus the data for the selectiol'r of the OCPD shall be obtained from the manufactuer of the contactot taking into account the rated operational curent, rated operational voltage and the corresponding utilization category. NOTE 2: This information is genemlly provided in co-ordination tables which summarize the combination ofdevices (OCPD. contactor or motor starter) able to maintain a safe behaviour for a given rated conditional shofi-circuit.
In a motor circuit the overload curent protection may be provided by separate overload rclay electrically connected with the contactor. In such a case protection ofthe overload relay shall also be achieved, since the overload relay may be damaged by the letthrough energy (l':t) of the OCPD. This infomation is generally provided in the manufactui'er's co-ordination tables.
176
536.4.2.3
Back-up protection of switches, Transfer Switching Equipment (TSE) or impulse relays
Switches cornplying rvith BS EN 60947-l or BS EN 60669-2-4, Transi'er Sl irching Equipruent (TSE) corrplying u'ith BS EN 60947-6-l and impulse telays complying with BS EN 60669-2-l are used to switch loads or circuirs (e.g. distributior switchboard, lighting circuit, specific load). These devices do nor provide protection againsr shoft-
circuit. thus they shall be protected by an oyercun'ent protective device (OCPD).
NOTE:
Fuse combinatior units to BS EN 60947-3 consist ofa sivitch and inte$ai liLse(s) and have a short-circuit capability declared by thc nranut'actuler which does not lequile the use an upstrcaln OCPD.
Should a shot-circuit occur on the load side ol a switch, the curent will flou, through both devices (OCPD and switch); therefore the let-through energy ancl the peak cuffent limited by the OCPD need to be compatible with the shofi-circuit withstand ofthe switch, the TSE or the irrpulse relay. Figure 536.9 gives
a
typical scllenatic for co-ordination of a switch with a short-circuit protective device (OCPD).
Figurc 536.8 Not used Fig 536.9
-
Co-ordination between OCPD and switch
The OCPD may also be situated downstleam of the switch, TSE or impulse relay provided that the connection letweerl tbe switch and the downstream OCPD is selectcd alrd erected so as to minimize the risk ofeafth faults and .hort-circuits. Silitches, Transt'er Switching Equiprrent and imptLlse relays shall be selected and erected in conjunction with the .hort-circuit prctective device declared by the manufacturer in order that their mted conditional shorl-circuit cuffent .: equal to or higher tl]an thc plospective sltoft-circuit cuffent at the point ofinstallatiou. The rated conditional shoft-circuit cuuent of the switch can only be obtained by typc-testing and thus the data fbr' ::'ie selection of the OCPD shall be obtained from the nlanufacturer of the switch, taking into account the l?ted :perational current and the rated operatiotal voltage.
.rr switches according to BS EN 60947-3, where the OCPD is not specified by the switch nrarufacturer, an ..ienrative nlethod lor co-ordination between the OCPD and the switch is as follows: the rated short-circuit making capacity of the switch is higher than the peak value ofthe prospective shoficircuil culrent at the point of i[stallation, and
the OCPD time-cunent charactedstic is within the limits oflcw ofthe switch. as stated by the manufhcturer, OI
the mted slloft-ci[cuit making capacity is higher than the peak value ofthe prospective at the point of installation, and
sllorlcircuit cu[ent
shot time withstand cuffent is higher than the prospective shoft-circuit cu[ent at the point of installation and the coffespondirg withstand time is longer than the operatiru time of the SCPD. if
tl're mted
applicable, or
if
at the prospective shofi-circuit cLnreDt" the protective device has an energy lerthrough (lrt) and cut-ot'f currelt not exceeding the values for d]e s$,itch provided by the manufactLLrer.
177
_--.--
536.4.2.4 Back-up protection of RCCBS In this regrilation. the OCPD cottld be replaced by an SCPD. RCCBs complying u'irh BS EN 61008 serics are intended to protect persons against elect c shocks. They may also be used to pl'o\, ide prolectiolr against fire hazards due to a persistent earth fault. These devices have a limited siroft-circuit current rvithstand capability. thus they shall be protected by an upstream overcun ent protecti\ e device. ShouLd a shorr-cilcuit occur. on the load side of a RCCB, the current will flow through both devices (OCPD and RC CB): rheretbre tlrc lct,through energy and the peak curent limited by the OCPD need to be cornpatible with the
short-cil'cuit $ithstand capability of the RCCB. Figure 536.10 gives a typical schenratic for co-ordination ofa RCCB with a short-circuit protective device.
Fig 536.10
-
Co-ordination between OCPD and RCCB
RCCBs shall bc sclected and erected in conjunction with the OCPD declared by the manufacturer in order that their rated conditional sltofi-circuit cu[ent is highcr than the prospective short-circuit cu-rent at the point ofinstallation.
Thc lated conditionai shoft-circuit curent of the RCCB with the OCPD, related to the relevant mted operational cLrrrent and rated operational voltage. is given by the manufacturer based on tests results according to BS EN 61008 selies.
The OCPD rrlay also be situated downstream of the RCCB provided that the connection between RCCB and dorvnstrearn OCPD is sclected and erected so as to minimize the risk ofcarlh faults and shofi-circuits.
536.4.3
Requirements for protection in case of overload
536.4.3.1
Overload protection of contactor or SCPDs
Corractors con.iplyiug with BS EN 6t)947-4-l or BS EN 61095 and SCPDS without integral overload protection. such as ICBs couplying rvillt BS EN 60947-2. shall be protected by an overload protective device. Devices for overload protection are selected for the protectiol of cables. For overload protection of contactors or SCPDs. the lated curlcnt of thc OCPD shall be selectcd according to manufacturers' information. In cases rvhere Regulation 433.3 permits omission ofoverload protection, co-ordination in case ofoverload does not apply
536.4.3.2
Overload protection of RCCB, switch, Transfer Switching Equipment (TSE) or impulse relay
Rcsidual current cir-cuit-brcakerc (RCCB) complying with BS EN 61008 selies are intended to protect pe$ons against eiectric shock. S\\,itches cornplying with BS EN 609'+7-3 ol BS EN 60669-2-4, impulse relays conplying rirh BS EN 60669-2-2 and TSEs conrplying with BS EN 60947-6-l are used to switch loads or circuits. None of thcs!'devices provide plotection against overload. theretbre they shall be protected by an overcu[ent protective clevice (OCPD).
178
Regulation 43 3. I rcquires that devices for overload protection be selected lbr the proiection of cables. For overload
protection of RCCBs and switches, the rated cu-rent of the OCPD shall rake account of the manufaclurer's information: in general, the OCPD is installed upstream olthe RCCB or the su itch. The rated current
ola switch or RCCB may
also be based on the application
ofdi\ ersity factors to the downstream
circuits according to Regulation 311.1, and the rated curent of the OCPD shall be selected according to the manufacturer's instructions. See also Regulation 536.4.202.
NOTE: wllen
usirg an RCBO instead of an RCCB, no f'ufiher consideration regarding orerload protection ofthe RCBO is
rleccssar].
Regulation 433.3 specifies conditions lor omission of overload protection. In such cases overload co-ordination does not require verification.
536.4.4
Requirements for selectivity between OCPDs equipped with under voltage relay
case offault (short-circuit or eafth fault) a high fault cufient may generate a voltage drop through the installation. Voltage drop may also occur i[ the installation for other reasons (for example, switchilg and reclosing of HV switching device).
ln
Wherc one undervoltage relay is installed in the OCPD on the supply side or elsewhere in the installation, possible undewoltage rclay operation shall not impair selectivity achieved between OCPDs ard/or RCDs in series.
Fig 536.11
-
Selectivity with OCPD and undervoltage relays
o c P D 1
o
o
r)ll.
C
C
P
P
:..l1al r08
D
D
::_-ail: ::
I
22
.urcl
For selectivity, undervoltage rclay operation sha11 be time-delayed according to the maximum shoft-circuit or eartll fault clearance time. ln all cases, instuctions plovided by the manufacturer shall be fulfilled in order not to irnpair' the safety ofthc electrical iustallation. on. :,:ior ( .:. Titof
536.4.5
Low voltage assemblies according to BS EN 61439 series
Theinte'acecharacteristicsofanassemblyconlormingtoBSEN61439seriesshallbecorrpatiblewiththeratings of the circuits to rvhich it is col1l]ected ard with the installation conditions. The characteristics of the assembly shall be declar-ed by the manufacturer, taking into account the interface characteristics ofthe relevant BS EN 61439
ploduct standard. s
not
536.4.201 Fault current (short-circuit) ratings The relevant f'ault cunent (shoft-circuit) rating ofthe assembly should be equal to or exceedthe maximun prospective fault current at the point ofconnection to tlte system. :Srso11s
plyitg ..rne of t,-ctive
The teflninology used to define the shofl-circuit rating ofan assenbly is given in the BS EN 61439 series as follows; ratcd short-tilne withstand current. I.,, rated peak wilhstand curent. lur ratcd conditional sbort-circuit curent. I... The assembly manut'actur-cr-'s ratings and instntctions shall be taken into accolul. 179
For ao installation with a 230 V silgle-phase supply rated up to 100 A that is under the contlol of ordinary persons, switchgear and controlgear assemblies shall either comply with BS EN 61439-3 having a suitable fault cunent (shofi-circuit) rating for the maximum prospective fault current at the point of connection to the systen or be a consllfiter unit incorporating components and protective devices specified by the manufacturer complying with BS EN 61439-3, including the 16kA conditional short-circuit test described in Annex ZB of the standard.
NOTE:
kA is cited from Engineering Recommendatior P25, the l6 lcA conditional rating described in Annex ZB of BS EN 61439-3, for incoming service equipment, will satisfy design requirements where the servicc cable is at least 2 mctres in length. When the single-phase PSCC value
of
19.6
536.4.202 Currentratings The relevant design current shall not exceed the rated cu[ent of an assembly (1,,A) or rated cu[ent of a circuit (I,,.) ofthe associated assembly, having taken any applicable diversity/loading factors into account. The teminology used to define the rating of an assembly in relation to load/design cunent used in BS EN can be summarized as follows:
-
6l4jS
Tlte rated current of an assembly (I",q) (A)o is the maximum load current that it is designed to manage and distribute. The rated curent ofa circuit (I..) (A) is stated by the assembly manufacturer, taking into consideration the mtings ofthe devices within the circuits, their disposition and application.
The cunent rating(s) of an assembly circuit may be lower than the rated current(s) of the device(s) according to their respective device standald, when installed in the assembly; therefore, the assembly manufacturer's ratings and instructions shall be taken into account. Rated divenity (loading factor) can be stated by the assembly manufacturer, e.g. for goups ofcircuits. The rated curent of a switch or RCCB (I,,.r and I,,,) shall be based upon: the sum of6nal circuit current demard after any applicable load divl]Isity factors, or thc sum
offinal circuit culTellt dernand alicr any applicable load diversity thctors togclhcr with allou'ances
fol diversity betu,ccn final cilcr.rits. or the sum ofthe downstream OCPDsT'circuit ratcd
curaent multiplied by a diversity factor.
Howevel overload protection shall not solely be based on the use ofdiyersity factom ofthe downstream circuits. To achieve overload protection of RCCBs or switches, the rated current ofthe OCPD shall be selected according to the manufactuer's instructions.
536.4.203 lntegration of devices and components The relevart part ofthe BS EN 61439 series shall be applied to the integration ofmechanical and electrical devices and components, e.g. circuit-brcakers, control devices, busbars into an empty ellclosure or existing low voltage assembly.
In low voltage assemblies to ttre BS EN 61439 series, e.g. consumer units, distribution boards, incorporated devices and conponents shall only be those declared suitable according to the assembly manufacturer's instructions or litemture. NOTE 1: The use of ildividual componeDts complying with their respective product standard(s) does not indicate their conpatibility when installed with other components in a low voltage switchgear and conffolgear asscnbly. NOTE 2: Incorpomted components inside the assclrbly can be from different manufacturers. lt is essential that all incorporated components shouidhavelrad their compatibility forthelinal enclosedarrangernents verifledbythe original manufachrrer of the asscmbly and be assembled in accordance with their instructions e.g. the consumer uDit. distribution board manufacturer. The original rnanufacturer is the organization that carried out the oiginal design and the associated verification ofthe low voltage switchgear and controlgear assenlbly to the relevant part ofthe BS EN 61439 series. lf an assembly deviates froln its original manufacturer's inshuctions, or includes components not included in the original ver.ification, thc person introducing the deviation becomes the original manufacturer with lhe corresponding obligations.
536.5
Documentation
The infonnatiol mentioned in the previous regulations for co-ordination of electrical devices may be found in manufacturers'documentation (e.g. catalogue, instuuction sheets, calculation software).
Whe[ the initial verification is made, the documentation conceming the selection ofdevices for co-ordination shall be addcd to the design documentation in accordance with the requirements ofRegulation 132.13
180
ISOLATION AND SWITCHING
537
General
537.1 ::l
This section provides requirements fbr:
(i)
non-automatic local and temote isolation and switching neasurcs tbr the preventiolt or removal ofdangers associated with electrical installations or electrically-powered equipment and machines, and
(ii)
tunctional switching and control.
537 .1 .1 Any device foI isolation and switching accolding ro Sections 162 lelevant requiremerrts included in this section.
to 465 shall comply rvith
the
i.)
ln ceftain instances, additional requirefl]ents may be necessary lbr contbined functions.
'j9
NOTE 1: Tablc 517.,1 sLLmnlarizes the luDctions provided by the dcvices for isolation and s$itching, togcther with indicarion ol rl,( r(lr\ anl product.ra ddrd*. NOTE 2: Foi sorre applicatioDs such
lnd
as
nrotor contlol, the switcJ'ing device needs ro withstand the inrush curent.
NOTE 3: Table 537.4 provides infonnation or sclection.
TABLE 537.4
gto
Device
-
Guidance on the selection of protective, isolation and switching devices Standard
Emergency
Furlctional
switchinglr
srvitching(i)
No
No
Yes
Isolation(r)
altd Switching device
INCES
BS EN 50428
BS EN 60669-l
No
Yes
Yes
BS EN 60669-2-1
No
No
Yes
BS EN 60669-2-2
No
Ycs
Yes
BS EN 60669-2-3
No
Yes
BS EN 60669-2-4
Yeslrr
BS EN 60947-3 BS EN 609,17-s-1
ruits.
(i)rltactor
ing to
BS EN 61095 C ircuit-breaker'
ItCD
No
Yes
\ts
No
No
Yes
BS EN 60947-4-l
BS EN 60898
Yes .3)
BS EN 609,17-2
Yes
BS EN 61009- I
Yes6l
Yes Yes
\ts
BS EN 60669-2-4
Yes
Its
BS EN 60947-3
Yes
Yes
No
\es
No
\o
No
\o
BS EN 61008 series BS EN 61009 series
l:r
ices
Isolating switch
ia1ls Or Plug ard socket-outlet
:.:: their
(< 32 A)
::.rIated
(> 32 A)
Plug ard socket-outlet
board
Device for thc conrlection of luminaire
serles.
Control and protective switching device lor equipment (L-PS)
in the Fuse
Device with
semiconductols
Luminaile Supporting Coupler
:
|ind in
PIug arld unsu itchcd socket-outlet
Ycs
BS EN 60947-2
BS EN 60309
Yes';r
Yesrrr
BS EN 60309 BS EN 61995-1
Yes'J,
BS EN 60947-6-1
Yesr l.r)
BS EN 60947-6-2
Ye.tI
BS 88 selies
BS EN 50428 BS EN 60669-2-
I
r)
Yes
No
No
No
No
Yes
No
No
BS 6972
No
No
BS 1363-l
No
Yes
BS 1363-2
No
.: -ro shall
181
BS
l36l-l
BS 1363-2
Yesdr(Relnoval of fuse li k)
Cooker Control Unll switch Yes -' Functior proYided" No -- Functioi not provided rLr
FLrnction plovided
ifrhe dcvice is suitable and narked with tlre symbol for isolation
(see BS EN 60617 identity number
s00288)
-/F
'r' See Regulalion 517.i.3.6. ,r Device is suitable tbr on-load isolation. i e. disconnection whilst calrying load curent' See G, In an installatjon lil.lning paft ofa TT or IT system. isolation requires disconnection ofall the live conductors Regulation 462.2. (5)Circuit-breakcrs nnd RCDS are p marily cilcuit plotective devices and. as sr:ch. they arc not intended for frequent load purposes ofisolation oI emergency switching s\\,itching. Infrcquent switching of circuit-breakels on-load is admissible for the to the manufactLuel's instructions shoLlld according stics load characte and ofoperations FoI a mol.e liequent duty. the numbel ftlnctional switching il] Table 537 4 should be be taken into accol lt oL an altenlative device from tllose ]isted as suitable for employecl.
ma*ed with the symbol fol on-load : An entry of ( I,3 ) rreans that the devicc is suitabie for onJoad isolation only if it is isolation ---lqand swjtching ale summarized, together with an NOTE 2: Ir the abovs rable. the functions providcd by the devices fol isolation indication o1' the rclc\ ant product standards.
NOTE
1
10 more than where at,] installation oI an iten of equjpment or enclosule contains live parts connected 537 .,1 ,2 to live gaining access person, before that any one supply. a durable wanring notice shall be placei in such a position arangement interlocking an unless the various supplies ionr. i.iLiu. *u"r.d ofthe rieed ro isolate those parls from concemed the circuits all to isolate provided is
may be used for Plugs ancl socket-outlets, connecto$ al1d devices for connection of luminaires 537 4' Table providing the isolaiion and switching functions in accordance with
537.1.3
plug from the outlet or conneclor The isoiation and srvitching functions are provided by the disconnection of the liom thc inlet. as aPPlicable.
537-1-4 537,1.5
Not u.;ed
of which requires a Wherc an installation is supplied from more than one source of energy, one provide that not more ofthe means ofearthing ofother sources and it is necessary to
means ofeatthing independent than one means Jfeanili.g is applied at
a,y time,
a
switching device may be inserted in the connection bet\'vee11the
neutml point and the ucatrs of earthing, provided that the device is:
(i)anrultipole.linkeds\\'itchillgdevicearrangedtodisconnectandconnecttheeafihingconductorforthe ''
(ii)
nppropriut" ,ource at substantially the same time as the related live conductors' or lelated live a switchirg device iuterlocked with a multipole, linked switching device inserted in the
conductolssuchthattheearthingconductorfoltheapplopatesourceshallnotbeintenuptedbeforethe
the live conductols ale leconnected' related live conductors al]cl shall-be re-established Ilot latel than when
of chapter 46 for a device switching devices provided in accordance with (i) and (ii) shall meet the Iequilements for isolation. 537 .2
Devices for isolation
537 .2.1
Devicesforisolationshallbeofatypeforwhichtheisolationfunctionisexplicitlyrecognizedbythe
relcvant product standard or as identified in Table 537 4
537.2.2
18?
Serlricorlductor devices shall not be used as isolating devices'
537.2.3 Der.ices suitable tbr isolation shall be selected according to the requi:ei--:::. overvoltage categories applicable at theil point ofinstallation.
-
:rri:r tr:3
r::.i
t-]n
the
Devices for isolation shall be designed for over voltage category III or lV except the plug ..; r p,ug and socket-outlet cornbi[ation identilied in Table 537.4 as suitable for isolation NOTE: Wher.e clectrically powcred equipment is witli[ the scope ol BS EN 6020.1. the requirem.nli l-or isolatiol of that standard apply.
Devices lor isolation shall be selected and/or installed so as to pre\enl un\\anled or unintentional closure (see Regulation 462.3).
537.2,4
This n.ray be achieved by locating the device in a lockable space or lockable enclosure or b}' padlocking or by other suitable n'reans.
537.2.5
Provision strall be made for securing offJoad isolating devices agailrst un$'anted or uniutentional
opening. This n]ay be achieved, for exanple, by locating the device ir a Iockable space or lockable enclosure ol by padlocking Altematively. the off-load device may be interlocked with a load-breaking one. Means ofisolation shall preferably be provided by a nrultipole switching device which disconnects all applicable poles ofthe relevarrt supply but single-pole devices situated adjacert to each other are not excluded, subject to the provisions ofRegulation 461.2.
537.2-6
oad
Each clevice userl fol isolation shall be cleally identified by position or durable marking to indicate the installation or circuit it isolates.
537.2.7
ing. i\uld
dbell
537
Where a link is inserted in the neutml conductor for isolating purposes, the link shall comply with the
.2.8
following requilemerts:
-
it cannot be removed without the use ofa tool, and it is accessible to one or more skilled persons only.
537.3 537.3.'1
:r1an
Devices for switching
Functional switching and control devices
.ir e
:.lllt
537
:
The chamcteristic ofthe load to be switched shall be considered (e.g. utilization category).
.3.1.1 The devices for functional switching ard control shall be selected in accordance with Table 537.4. 537.3.1.2 Furlctional switching devices shall be suitable tbr the most onerous duty thcy ae irtended to Perform.
lor
537,3.1.3
Functional switching devices may control the current without necessarily opening the correspondilg
poles.
NOTE: ,.rcs
537.3.2
a
: i1lore :31'l
:rr
Semicoiductor switching devices and some control auxiliaries are exantples of devices capable of intempting the cLur-ent in the circuit but not opening the conesponding poles.
tlle the
Devices for switching off for mechanical maintenance
.3.2.1
Selection aDd erection ofdevices for switching off1br mechanical mailtenance shall be in accordance rvith the following regulations and shall colrply with Regulation group 537 2. NOTE: Wher.e elecflically powered cquipment is within the scope of BS EN 60204, the requircments for switching off for 537
mechanicai maintcnance ::
-i livc
' ri the
','ited.
- -'rr ice
537
.3.2.2
Devices for switchirg off for mechanical maintenance shall be inserled in the main supply circuit.
Where a switclr is providcd 1br this purpose, paft of the installation.
lnte[uption of
a
tbe
(i) (ii)
it shall be capable of cutting off the full load current of the relevant
circnit tbr tl]e control of mechanical moverrent is permitted only where a condition equivalent to
the direct interruption
' '\\
ofthat standard apply
olthe main supply
is provided by one
ofthe fo)lowing:
Supplementary safeguards, such as mechanical retainers
Compliance with the requirements ofa British or Hamonized Standard specification for the cotttt'ol devices used.
NOTE:
Switching offfor rnechanical maintenance may be achieved, for example, by orre ofthe following: multipole su'itch
537 -3.2-3
cilcuit-breaker control and protective switching device (CPS) control switch operating a contactol plug and socket-outlet.
Devices for switching off lor mechanical maintenance or control switches for such devices shall
require manual operation. The open position ofthe contacts ofthe device shall be visible or be clearly and reliably indicated. The indication required by this regulation may be achieved by the use ofthe symbols 'O' and'I'to indicate the open and closed positions respectively.
Devices for switching off for mechanical maintenance shall be clearly identi{ied by position or
537.3.2.4
durable marking so as to be identifiable for their intended use.
537.3.3 NOTE:
Devices for emergency switching off
Etrergency switching off is an emergency operatio[ intended to switch offthe supply ofelectrical energy to all or part sk ofelectric shock or another isk ofelectrical origin is involved. ofan installation where
a
537,3.3.1
Selection and erection of devices for emergency switching following regulations and shall comply with Regulation 537.2.
NOTE:
off shall be in
accordance
with the
Where electrically powered equipme]tt is within the scope ofBS EN 60204, the tequirements for enrergcncy s\vitching
offof
that standard apply.
537.3.3.2
The devices for emergency switching off shall be capable of breaking the full load current of the relevant parts ofthe installation taking into account stalled motor curents where appropriate.
537.3.3.3 Means lor emergency switching offmay consist of: - one switching device capable ofdirectly cutting off the appropriate supply, or - a combination ol devices activated by a single action for the purpose of cutting off the appropriate
supply.
Plugs al1d socket-outlets shall not be provided for use as means for emergency switching off.
537.3.3.4
Devices for emergency switching off shall provide the switching of the main circuit.
Hand-operated switching devices for direct intenuption ofthe main circuit shall be selected where practicable. Remote control switching of circuit-breakers, control and protective switching devices or residual cu[ent devices (RCD) shall be opened by de-energization of coils, or other equivalent failure-to-safety techniques/actuato$.
537.3.3.5
The means of opcrating (handles, push-buttons, etc.) devices for emergency switching off shall be clearly identified, preferably by colour. [f a colour is used for identification, this shall be RED with a contrasting background (e.g. yellow).
NOTE:
The contrasting background rnay or may not include text.
537.3,3,6
The means of oper ating shall be readily accessible at places where a danger might occur and, where appropriate, at any additional remote position from which that danger can be removed. Devices for emergency switching offshall be so placed as to be readily identifiable and convenient for their intended use.
537.3.3.7
The means of operation ofa device for emergency switching off shall be capable of latching in the 'OFF'position, unless both the tneans ofopemtion for emergency switching off and for re-energizing are under the contlol ofthe same person.
The rclease of an emergency switching device opemted remotely shall not re-energize the relevant pan of the installation. The oper.ation ofthe emergency switching device shatl have priority over any other function relative to safety and shall not be inhibited by any other operation ofthe installation.
537.4 Firefighter'sswitches 537.4.1 Firefighter's su itches shall comply rvith BS EN 60669-2-6 or BS EN 60947-3. 184
537.4.2 A lirefighter's ss.itch sJrall be provided in rhe low volrage circuir .r;qi1 rng: (i) outdool liglrting installatiorls operating at a voltage exceeding loir rcriiag;. rnd (ii) indoor dischatge ligtrting installatiors operating ar a voltage exceedins lo\,. \ (rlrase. 'fhis requirtment does not apply to a portable discharge lighting hurinaire or to f'ed from an accessible socker-outlet
NOTE:
a sisn t
irating not exceeding
100 W and
Installations in certain prel)1ises subject to licensing conditioDs. such as perrrrl .raiion tbrecoufis, nray requir-e the illstallation of a firelighter's switch.
537.4.2.1 Every outdool installation on each silgle premises should rvhererer practicable be controlled by sirgle lirefighter's switch. Sirnilarly, every intemal installation in each single prernises shoLrld be controlled by
a a
single firefighter's switch i[depcndent olthe switch for any outdoor installation.
537.4.2.2 Every firefightcr's switch should comply with the following requirements. r.r,here applicable: (i) for an outdoor installation, the switch should be outside the building and adjacent ro the equipment, or altematively
a notice indicating the position ofthe switch should be placed adjacent to the equiprnent and a notice should be fixed neat the switch so as to lendel it clearlv distinquishable
(ir)
for an indoot installation. the switch should be in the main entrance to the building or in another position to be agleed with the locai fire authority
(iii) the switch should be placed in a conspicuous position. reasonably 2.75 l.r fiorr the ground or the standirrg beneath the switch.
accessible to firefighte$, at not more than
537.4.3 A lirefighte/s switch shall be easily visible, accessible and marked to indicate the installation or pafi of the ilstallation u'hich it controls 537.4.4 The lbllowing infomation shall be distinctly and durably marked on the fireflghter's switch in a position where it can be seen clearly by a person standing on the ground at tlte intended site. witl'rout openi[g the enclosure and when the switch is installed; 'ON' and'OL-F' positiors" in lettels lrot less than 10 nrrr high: letters reading 'I IREI- IGHTER'S SWITCH'or'L-IRE SWITCII' in letters nor less rhan 10
nm high.
Once installed, the handle offposition shall be up.
NOTE: 538
The'ON'position nteans powered and dre 'OFF' position means unpower-ed.
MONITORING DEVICES
538.1
lnsulation monitoring devices (lMDs) for lT systems
538.'t.1
General
lMDs shall be in accordance with BS EN 61557-8. An IMD is intended to permanently nronitor tlle iusulation resistance ofan lT system and provides an alam where :- :.4
the insulation resistance R,.is below the response value R,. Ra is the response value
ofthe IMD
as described
in BS EN 61557-8.
R[is
tl']e insulatiotr resistance between the system to which it is connected and either the eafih, the PE conr]ectiolr anothel reference point fot protective equipotential bonding.
01'
Examples ofthese systeDs would bc an electrical installation, a mobile generator or a saf'ety service.
An IMD shall be installed in an lT systenl where selected to meet with the requirement of Regulation zll1.6.4. IMDs shall be installed
as close as
practicable to the origin ofthe pafl ofthe installatio,r to be monirored.
lnstructions shall be provided indicating that when the iMD detects an insulatior fault to eanh. the ilsulation t'ault shall be located and eliminated in order to restore normal operating conditions with dre shortest practicable delay. Where the 1T systen is used for continuity of supply, the occuffence ofa first insulation thult shall be indicated at a suitable locatior'r so it is audible and/or visible by instructed or skilled pe$on(s).
NOTE:
This alaln may be relayed though a buLilding management system (BMS).
It is recommended to colducton and earth.
use an
IMD that signals an intefuption of the ureasuremelr connections to the system
538.1.2
lnstallation of insulation monitoring devices
Where a ncutr.al cotductor is clistlibuted, an insulation monitoring device (lMD) may be connected to the neutral conduclor. In tltis case. no overcunent protective device shall be inserted in the conductor connecting the IMD to the neutlai.
An IMD shall be corutected symmetrically or unipolar-iy between the live conductors and earth or the PE connection ot alother ret'ereuce point ibt protective equipotential bondilg. Where the neutral conductor is not diStributed. the 'line' tenninal of the IMD may be connected: (i) either to an adificial neutral point with thc three impedances connected to line conductors' or
(ii)
to a line conductol.
whcre. in a polyplrase system. the IMD is connected between one line conductor and eal1h, it shall be suitahle to withstancl at least the linc-to-lil,]e voltage between its
NOTE:
This Iolrage appears across these two tenninals
'line'teminal and its 'eafih'teminal' ir the case ofa single insulation fault oD another
line conductot
For DC installations. rhe 'line' terminal(s) of the IMD shall be connected either directly to the midpoint, to one or all of the supply conducto$.
if
any' or
point The supply circuit of IMD shall be connected either to the installation on the same circuit ofthe connecting source' the 'line'terminal antl as close as possible to the origin ofthe systern, or to an auxiliary
of
insulation Thc corDecting point to tl're installatior shall be selected in such a way that the IMD is able to monitor the ofthe installatior in all operating conditions. Where the inslallation is supplied from r11ore thar one power supply, connected in parallel, one IMD pel supply shatl All other be used, provicled t)iey are iiterlocked in such a way that only one IMD remains connected to the system. pre-existing any without supply of this reconnection the power enabling supply, IMDs nonitor thc diicolnected
insulation fault.
lMDs shall be able to lncasure the insulation resistance of the system if DC components caused by electronic eqrlipment. e.g. rectiflers ol collvertols, are contajned in the fault curent.
538.1.3
Setting of the insulation monitoring device
The IMD shall have a selection ofsetting values and be adjusted to suit the respective installation. When operating nonnally with the maximum ofloads connected, the IMD shall be set to a lower value con espolding to the ool.11-Ial insulaliol-I of tlle system.
NOTE:
A r,alue ol 100 A/V (300 OIV for pre wamirg) ofthe mted system voltage is an example oftypical setting vallles.
Whcre IMDs arc installed in locations where ordinary persons have access to their use they shall be selected tool or and/or installecl in such a way that it shall be impossible to modify the settings except by the use of a key, a a
passuord.
538.2
Equipment for insulation fault location in lT systems
been Equipment for insulation t'ault location shall be in accordance with BS EN 61557-9. Where an [T system has location the fault enabling devices IMD with sclec-ted for contiluity of service. it is recommended to combine the on load. Their lunction is to indicate the faulty circuit when the IMD has detected an insulation fau1t.
538.3
Monitoring of off-line circuits
The iusulation monitoring of circuits switched off may be carried out in TN, TT and IT systems with insulatiotr
is oronitoring devices (IMDi) provided that the IMD is automatically deactivated whenever the safety equiptnent poles ofthe system. fro[r all isolated circuits are activated. A prer.ccluisite tbr it is that tlte monitored electrical NOTE: As an cxanrple. this can be applicabJe to a circuit comprising safety equipment which is nolnally de-energiTed such
thrt the salily
equipmcnt is allowed to lr'ork without intervention ofsupply
du
with the optron The reduction ofrhe insulation level shall be inrlicated locally by either a visual or an audible signal of rcl'note indication. from the installation during the off-load insulation measuring process, the insnlation levcls ro be mcasurcd arc generally very high. The alam threshold should be above 300 kQ.
Ilthe equipment
186
is disconnected
I
ng the emergency' I
538.4
Residual current monitors (RCMs)
538.4.1
General
RCMs shall comply with BS EN 62020.
An RCM peuna[ently monitors leakage and fault cunents to earth of the do\ nsream insi"]laiion or pan ihere of and is iltended to infom the usel about the level ofthese currents ofthat part ofthe insiailation being merniterred. RCMs are not intelded to provide protection agaimt electric shock. Where an RCD is installed upstream of the RCM, it is recommended that the RCI\l be set to a residual actuatin-s curent no higher than halfofthe rated residual operating current (I1") of the RCD.
It is recomnended that RCMs ale installed at the origin ofthe outgoing circuits. RCMs shall initiate an audible and/or visual signal, which shall continue as long as the fault persists.
538.4.2
RCMS installed in lT systems
I
In IT systerrs where interruption of the supply irr case ol a first insulation fault to earth is not required or not pemitted, RCMs rnay be installed to indicate the occurrence ofa first insulation fault from a live part to exposedconductive-parts or to earth in accordance with Regulation 411.6.4.
I I
Where used in IT systems, it is recommended to use directionally discriminating RCMs, in order to avoid unwanted signalling of leakage cuffent w]ren high leakage capacitances are liable to exist downstream lrom the point of
installation ol the RCM.
I
€^o'\
f",*3
187
Annex A53
(lnformative) Device functions and coordination Table A53.1
-
Devices and associated functions FunctioIrs
Devices
Product
OCPD(N
SCPDA'
RCDO)
Standard
Overload protection
Short-circuit
Residurl
protection
current
Switching only
protection Circtit-breaker
x
Yes
Yes
No
No
No
No
Yes
No
Yes
Yes
Ycs
No
Yes
Yes
Ycs
No
BS EN 60947-2, Annex M
Yes
Yes
Yes
No
BS EN 60947-2, Annex O
No
Yes
No
No
BS hN 60269 series
Yes
Ycs
No
No
BS EN 60269 series
No
Yes
No
No
BS EN 60947-6-2
Yes
Yes
Ntr
No
BS EN 60947-4- l
No
No
No
Yes
BS EN 60947 2
BS EN 60898
I
BS EN 60898-2
x
RCCB
BS EN 61008 series BS EN 62423
x
RCBO
X
BS EN 61009 series
BS EN 62423
x
x
CBR
BS EN 60947-2,
Annex B MRCDT
x
ICB
Fusc
x
x
* ith full
x
rangc breaking
capacity (e.g. gC. gM)ir) Fuse
x
with
partial range brcaking capacity (e.g.
aMlr)
x
CPS
Contactor
BS EN 61095
Overload relay
BS EN 60947-4-1
Yes
No
No
No
Switch or switch -disconnector
BS EN 60947-3
No
No
No
Yes
No
No
No
Yes
BS EN 60669-2-2 BS EN 60669-2-4
BS EN 609,17-6-l
TSE
rr) fuse
188
combination units according to BS EN 60947-3 are considered in this row
1r)
generic abbreviations used in this docunent for devices
rr)
when associated with a circuit-breaker
Basis of correct co-ordination
A53.1
The basjs ofthe co-oldiuation between e)ectrical ccluipment is to take
uJr.,:::.,-j
.- i
,!.!ie1 e(ri]rbination oftheir'
,.lectrical ,'ltat'uttet'i
Selectivity between electrical devices provides continuity of seNice and thus avoids dargers lilked to the loss of supply of speciflc cilcuits.
Parameters
As3.2
The panleters lbr the corect co-ot'dination between electrical devices rtay be:
-
design cufl'ent prospective shoft-cit'cuit or l'ault current operating timc of devices system voltage energy (tet-through lrt values) peak let-through current.
In addition, lbr fuses, the fbllowing parameterc should be corsidered: pre-arcing Irt and pre-arcing time operating Irt and opemting ti1ne.
Device co-ordination table
\,r
TabteA53.2 shows the types ofcombinatiot ofdevices and cells to show how various tnodes ofco-ordination can aft'ect safety.
\o
\o
\o
\o
-
Table 453.2 Rc!Ulition
Device co-ordination in a LV electrical installation Devices involved
\lodes of co-ordinatioI1
Impact on
of
safety
installation 536.4.
Impact or1 safely due to corltiruity of service
Between OCPDs
t.2
536.4. L3
Selectivity 536.,1.
r.1
536..1.1.5
Between RCDs
Yes
Between OCPD and
Yes
RCD 516.4 2.l
Combined sholt-citcuit protection
5i(,.,1.2.1
Cullent ol time based conditiolls
5i6.4.2.1
Back-up protection
ir
case
OCPDs
Yes
Between OCPD and contactors. overload relays
Yes
Bet$'een OCPD and
switched TSE or
ofshort-circuit
impu)se relays Betweerr OCPD and
516,1.2.4
Yes
RCCB
Bctuccn OCPD and
5t6.,1.3.1
Ycs
contactor or SCPD 516.4.1.2
Protcclion in case ovclload
5i6.'+.3.2
ol
Between OCPD and switched TSE or inpulse relays
Yes
Between OCPD and
Yos
RCCB Voltage based
516..14
conditions
a53.3
SelcctiVity
Bet\\,een OCPDs equipped rvith
undel-voltagc lclay
Between circuit-breakers or circuit-breaker and cPS or circuit-breaker and overload relay or circuit-breaker and motor starter
Sclcctivjty il1 casc ofoverload is vclificd by the con.rparison oftime/curert chamcteristics ofthe devices involved' of the The naximum operating tirne of the device on the load side must be lower than the non{dpping tine provides axes cunent time and the in both circuit-bteakel loi any ove oad currcnt. Separ-ation ofthe characteristics seleclive opcraliol1 i0 this zonc.
A53.4
Between fuses
involved' Selcctivity in case of ovetload is vclilled by the compalison of time/current chalacteristics of the fuses the_supply fuse on pre-arcing time ofthe than the lower Thc total operating time ofthe flrse on the load side must be of l6 A and above sicle. Fuses to BS EN 60269-2 of the same utilization category (e.g. type gG) with rated curent characteristics in ofthe gleatel sepalation or is 1.6:1 cunents u.ill proviclc total selectivity ifthe ratio ofthe lated borh the time and current axes provides selective operation in this zone'
A53.5
Between circuit-breaker (upstream) and fuse (downstream)
Selectivity il case of overload is verificd by cotllparison of the time/cufent chamctefistics, taking into account the the tr-ip s;tting of the cilcuit-bteakel u,here applicable. When using published time-curent chalacte stics, time cuNe operating minimum and the device downstream taken for the be olaximum opeiating titre cur\e must current axes provides must be taken for the upstream device. Separation of the chamctelistics in both the time and selqctive opcmtion in this zone.
453.6
Between fuse (upstream) and circuit-breaker (downstream)
into account the Sclecti!ity in case oloverload is verified by comparison ofthe time/cuffent chamctefistics, taking as given by I ip setting of the cilcLiit-breaker \<ere applicable. The nraximum operating tirne ofthe circuit-breaker product standard. the nanutncturer lnust be lo\\,er tlran the ininimum pre-arcing tirne ofrhe fuse as given by the in this zone' Sepamtion of the chafacteristics in both the time and culrent axes prol'ides selective operation
190
Between circuit-breakers
A53.7
Generally, reference should be n.rade to the manufacturers'docunentalion. In principle, selectivity is assured up to the fault current level at which the peak current lerthough ofthe downstrean ciriuit-bieaker is less than the peak value conesponding to the instantaneous tripping ler el ofthe upstream cjrcuitbreaker. Where the upstream circuit-breaker has dedicated selective behai iour. lhe selectility lilrit might be higher.
A53.8
Between fuses
Selectivity ilr case of shofi-citcuit is verilied by comparison of thc I:t values. The maximrur operating Irt value of the fuse on tlte load side should be lower than the minimum pre-arcing []t value ofthe t'use on the supply side. Fuses to BS EN 60269-1 of the same utilization categoly (e.g. type gG) with rated curett of l6 A and above will provide total selectivity if the mtio ofthl3 rated currents is 1.6:1 or greater.
A53.9
Between circuit-breaker (upstream) and fuse (downstream)
Ttre peak let-through cu[ent of t[']e fuse should be lower than the minimum instantaneous tripping curent of the circuit-breaker'. Data for peak values of fuses should be taken from the relevant standard or the manufacturers' documentation. data is taken 1ioru the lnanufactulet. this should be stated in the documentation olthe installation.
A53.'l
O
If
Between fuse (upstream) and circuit-breaker (downstream)
The minimuru pre-arcing lrt value ofthe fuse should be higher than the maximum let-through Irt Yalue ofthe circuitbreakcr for any shofi-circuit cun'ent up to the maximum prospective shofi-circuit cuffent to be considered. Data for I:t values of f'uses should be taken fiom the relevant standard/or the malufacturers' documentation lf data is taken frorn the matrulacturer. this should be stated in the documentation ofthe installation. The maximum let-through I:t value ofthe circuit-breaker should be obtained ftom the manufacturers' data.
Possible fault currents in systems with semiconductors
Io the diagrams of the following Figure 453.1, circuits with most likely fault cuffents in connection with semiconductor devices are shown.
rd
Figure A53.'l
-
Possible fault currents in systems with semiconductors
Circuii diagram with fauh
Shape of oad cuffent /L
Shape of earlh fau I
c!rent
/F
RCD lripp ng
AC, A, F. B
1
AC. A. F. B
2 L1
L2 L3 N
3
lingle
A,F.B
bridge
L
Circuil diagram wilh iault
Shape of oad
.!(ent
/L
Shape of earih fau l curent
/F
RCD
5
Two pulse bridse, ha f conlrolled
A,F,B
L N
PE
6
Slngle-phase wilh smooth
.g
B
L1
L2 L3 N
PE
wo-Pu se brldge betvveen phases
B
L1
t2 N
PE
8
B L1
L2 L3 N
PE
9
B
L1
t2 L3 N
PE
192
t
pp ng
CHAPTER 54 EARTHING ARRANGEM ENTS AN D PROTECTIVE CON DUCTORS CONTENTS 541
GENERAL
542
EARTHING ARRANGEMENTS
542.1
General requiremenls
542.1.2
Supply arrangements
542.1.3
lnstallation earthing arrangements
542.2
Earth electrodes
542.3
Earthing conductors
542.4
Main earthing terminals or bars
543
PROTECTIVE CONDUCTORS
543.1
Cross-sectional areas Types of protective conductor
543.2
543.5
Preservation of electrical continuity of protective conductors Combined protective and neutral (PEN) conductors Earthing arrangements for combined protective and functional purposes
543.6
Earthing arrangements for protective purposes
543.3 543.4
543.7
Earthing requirements for the installation of equipment having high protective conductor
cuffents 543.7.'l
General
543.7 .2
Socket-outlet final circuits
544 544.1
PROTECTIVE BONDING CONDUCTORS Main protective bonding conductors
544.2
Supplementary bonding conductors
'193
CHAPTER 54 EARTHING ARRANGEMENTS AND PROTECTIVE CONDUCTORS GENERAL
541
Every ]lteans ofeathing and every protective conductor shall be selected and erected so as to satisty 541 .1 the lequircDents of the Regulations.
Thc earthirg systern ofan installation may be subdivided, in which case each parl thus divided shall conply with the reqLLitements ol tltis chapter 541 .2
Where there is also a lightning protection system, reference shall be made to BS EN 62305'
541 .3
EARTHING ARRANGEMENTS
542
General requirements
542.',|
The eafihing arrangements ntay be usedjointly or separately fol protective and functional put-poses, according to the rcquirenents of the installation
542.1.1
S4Z-1.201 The maill eafthjng teminal sha]l be connected with Eatlh by one of the methods described in fom a pafi Regulations 542. .2. I to 542.1 .2.3 , as appropriate to the type of system ol which the installation is to and in corrpliarce with Regulations 542. I .3. I and 542. I .3.2. NOTE: Reter to Pafi 2 and Appcrdix 9 lbr dellnitions ofsysten]s 1
542.1.2
Supplyarrangements
For a TN-S system, rneans shall be provided for the main eatlhing terninal ofthe installation to be colnectecl to the eafihed poillt ol the source of energy. Pafi of the connectiol rnay be fotmed by the distributor's lires alld equipmerl.
542.1.2-,1
TN,C-S systerr, wherc prcrective multipie earthilrg is ptovided, means shall be providcd lbr the main eafthing terminal oltlre installation to be connected by the distributol to the neutral ofthe source ofenergy'
542.1.2-2
For
a
an For.a TT or IT systenl, the main eafthing temiual shall be connected via an eafthing conductor to 542.2 earth electrode corrplying with Regulation
542.1-2.3
Whcr.e the supply to an ilstallation is at high voltage, protection against faults between the high voltage supply and earth shall be provided in accordalce with Section 442
542.1.2.4
542.1-3
lnstallationearthingarrangements
542/1.3.1 The earthing arangements slla1L be such that: (i) the value of impeclance from the consrnner''s main earthing terminal to the earthed poil1t ofthe suppty tbr TN
Earlh tbr TT and tT systens, is in accordance with the protective and functional requirements ofthe ilstallation. and cottsidered to be continuously effective, and l'ault cul.lents a[d protective conductor cuffents which may occul are carried without dangel, systens" or
1()
(ii)
earth particularly fiom thertnal, thelnomechanical and electromechanical stresses, and
(iii)
they are adequately robust or have additional mechanical protection appropriate to the assessed conditions of cxternal inlluel ce.
S4Z-,1.3.2
plecautions shall be taken against the risk ofdamage to other rrctallic pafts through electlolysis.
Where a lumber of installations have separate eafthing arrangernents. any protective conducto$ to flow conunou to aury of these installatiols shall eithel be capable of carrying the rnaxillnm fault cu[ent )ikely a1ly other of an'angements through rhem or be ear.thecl withiD one installatiofl olly and insulated t'rom the eatlhilg conductot protective the instaliation. I11 thc latter circumstances, if the plotective conductor fonls part ofa cable, shall bc earthecl only in the installation containing the associated protectivc device
542.1.3,3
542.2 542.2.1
Earth electrodes 1'he design userl fbr, and the colstruction of, an eafth electrode shall be such as to rvithstand dautage
and to take account of possible increase in resistalce due to corrosiol't'
542.2.2
(i) (ii) iii) (iv) (v) (vi) (vii) (
Suitablc carth electrodes shall be used. The lbllou purposcs of the Regulations:
rni
:..:r
-
:
i:fih
electr.odc are recosnized for the
Earth rods or pipes Earth tapes ol wires Earth plates Underground shxctural metalwork elrbedded in fourdations or other metal$ ork installed in the foundations Welded metal reinlorcernent ofconcrete (except pre-stressed concrete) embedded in the ground Lead sheaths ard other netal coverings ofcables. where not precluded bl.Regulation 542.2.5
othcr suitable underground metalwork.
NOTE:
Ftulher
inlb ration
on earlh electrodes can be found in BS 7.1i0.
542.2.3 Where foundation earth electrodcs are installed. the materials and dinrensions ofthe earlh electrodes shall be selected to withstand corrosion and to have adequate mechanical strength. NOTE: lfa
lighhiDg protection system (LPS) is present. BS EN 62305-l applies.
542.2.4 The type and embedded depth ofan earrh electrode shall be such that soil drying and freezing not increase its resistance above the required value.
rl
542.2.5 The usc. as al eatl}t electrode, ofthe lead sheath or other metal covering to all ofthe following conditions: (i) (ii) (iii) (iv)
will
ofa cable shall be subject
Adequate precar.rtions shall be taken to prcvent excessive deterioration by corrosion The sheath or covering shall be in cft'ective contact with Earth The consent ofthe ouner ofthe cable shall be obtained
Auangements shall exist fot the owner ofthe electrical installation to be wamed ofany proposed change to the cable which rnight aft'ect its suitability as an eartlr electrode.
542.2.6 A metallic pipe for gases or flan.rmable liquids shall not be used as an earth electrode. The metallic pipe ofa water utility supply shall not be used as an earth electrode. Other rnetallic water supply pipework shall not be used as an earth electrode unless precautions are taken against its removal and it has been considered for such a use. 542.2.7 542.2.8
Ar carth electrode shall not consist ofa metal object immersed in water
Wherc an eanh electrode consists ofparts that mustbe connected together, connections shall be made by rveldiug, pressule connectoN, c]amps or other stlitable mechanical connectors.
542.3 :TN 1:11ts
:-:ieI.
Earthing conductors
542.3.1 Every earthing conductor shall comply with Section 543 and, where PME conditions apply, shall meet the requirements of Regulation 544.1.1 for the cross-sectional area of a main protective bonding conductor. In additiou, where buried in the ground, the eafthing conductor shall have a cross-sectional axea not less than that stated in Table 54. l. For a tape or stdp conductor, the thickness shall be such as to withstand mechanical damage and conosion. NOTE:
For futther infunnation sce BS 7430.
TABLE 54.1 Minimum cross-sectional area of a buried earthing conductor
::tol1s
Not protected against mechanical .
.,tors
io* -
damage Protected against colrosion by
2.5 mmr copper
16 mnrr copper
l0 mmr
16 rnmr coated steel
sheadr
-,rheL
:.atol'
a
Not protected against coffosion
steel
25 nrml copper' 50 mnl: steel
--:nlge
542.3.2 The connectiol'l of an earthing conductor to an earth electrode or otlret means of earthing shall be soundly rlade and be electrically and mechanically satisfactory. and labelled in accordance with Regulation s14.13.1(i). It shrll be suitahlr protccted aeainsl corro\ior.
li I
Main earthing terminals or bars
542.4
542.4.1 h eren installation a main earthi g rel.util1al shall be provided 10 connect the lbllowing to the eafihing conductor:
(i) The cilcuit protective corlductols (ii) The protective bonding conductols (iii) Functionalearthingconductors(ifrequiled) (iv) Lightnirg protection systern bondir)g cordLrclor. if any (see Rcguiatiorl 4l1.3.1.2). 542,4.2 To thcilitate rneasule[e|t oftlie fcsislancc ot the eafil]ing alrangements, nlealrs shall be provided in an accessible position tbr alisconnecting the eafi[ring conductor'. Such means may conveniently be cornbined with the main earthilg ternrinal or bar'. Any joint shall be capable of discorulection orrly by means ola tool.
PROTECTIVE CONDUCTORS
543
Cross-sectional areas
543.1
The cross-sectional area of evely protective corrductor, other thall a protective bonding conductor,
543.1.1 shall be:
(
(i) ii)
calculated in accordance with Regulation 543.1.3. or selected in accordance witb Regulation 543.1.4.
Calculation in accoldance with Regulation 543. LJ is necessary iltlre choice olcross-sectional area olline conductors has been dcteuined by consitlerations of shorrcircLrit cuu'ent and if the eath lhult cunent is expected to be less thar the short-circr.rit curlelrt.
lf the protective conducfor': (iii) is rot an integral part of
(iv) (v)
a cable,
or
is not formed by conduit, dlLcting or tlunkirlg. or is not cortaiued in an encloslre tbt.lrrcd by a wiring system,
the cross-sectional area shall be oot less than 2.5 [un] copper equivalent ifprotection agairst rnechanical damage is provided, ard 4 Drrur copper equivalcnt il'nrcchanical p|oteclioI is not plovided (see also Regulation 54i.3.I ). a protective conductor Lruried in the ground Rcguiation 542.1.1 fbr earthing conductors also applies. The crosssectional area of a protective bot]dillg co[dLrctol sha]l cornply with Section 544.
For
543,1.2 Where a protective conductol is comrlon to two ol mole cilcLlits. its closs-sectional arca shall be: (i) calculated i[ accordalce with RcgulatioD 5u13, 1.3 fbl the r)rost onerous of the values of 1aLilt cunent alld operating time encountered in each of the valior-ts circuits. ot'
(ii)
selected in accodance with Rcgulntion 543.1,4 so as to correspond to the closs-sectiolal area ofthe Iargest
lire cordirclor ol'the cir(uil:.
543,1.3
The cross-sectional alea. whete calculated, sliall be not less than tlre valuc dctcrnined by the
followirg lbnlrula or shall
be obtained by rel'er:ence to tsS 7454r
S: NOTE:
il{k
Tltis equatio[ is aD adiabatic cquatioo .rntl rs applicable fbr disconneciion times not exceeding 5s.
where: S
I
ofthe corductol in nrml is the value in amperes (rus tbr AC) of fault culrert lbr a thult ol negligible impeda[ce, which is the nominal cross-sectiooal area
can
flow through the associatecl protective device- due account being taken of the cufferrt ]inliting elTect ofthe circuit ill1pedances and tlre linriting capabi]it] (lrt) olthat protective device
t k
ofthe protective device in seconds corresponding to the t'ault cu el'rt I anperes is a factor taking accoult oftl]e resistivity. teurpelatule coeflicient and heat capacity olthc conductor is the operating tilr're
lnaterial, and the appropriate initial and linal lenrperatrLres.
196
\hlues of k ior pr.rre.-rir e conductors in \ aliolls use or service are on d1c initial and final tempcralures indicated in each table.
as
given ln Tiibl..
j-i.l
10 6.
\\ here the applicatiotl ofthe formula produces a non-standard size. a conrluclrrr harinr a iectionai area shall be used
The vaiues are based
larger. starldard closs-
TABLE 54.2 _ values of k for insulated protective conduclor not incorporated in a cable and not bunched with cables, or for seperate bare protective conductor in contact wiih Jr" but not bunched with cables, "ou"rinq where the assumed initial temperature is 30 "C Irsulatioll ofprotective conductor or cablc covcrir!:
\laterial ofconduclor
90.c
"t'
90
thermoplasric
thennoplastic
themlosettins
143/133'k
l43i13l*
176
95/88*
95j883
lt6
52
52
( opper
Alurrinium Stecl
Assumed irlitial temperature Final temDemhn-.
"c
70
30 160
"c
30
"c/140 "c'N
64
"c
30
160'C/1.10'C*
"c
250 "C
{bove 300 urnrr
-
TABLE 54.3
Values of k for protective conductor incorporated in a cable or bunched with cables, where the assumed initial temperature is 70.C or greater \latcrial ol conductor L
opp.'r'
llunrinium lisuurcd initial tcnlperaturc : rnal
lenrrT er'anrre
Insulation material thermoplastic
90 .c tl'rel.lnoplastjc
thcfirosetting
i t5/103'l
100/86*
i43
76t68*
66!57*
94
"c 160.C/t40.c*
90.('
70
"c
70
90.(
90
.c
250 .C
160'C/140.C*
* \bove 300 mm-l TABLE 54.4
-
Values of k for for the sheath or armour of a cable as the protective conductor \hr!'r'ial of conduclor
Insulatiolt l'natc.ial 70
"c
thennoplastic
90 .(' the]]noplastic
thelntosellinc
90
"c
-{lumtnlum
9i
85
85
Sreel
5t
46
Lead
16
)6
23
23
\ssumcd iuitial tclrperaturc Final tcrnperatur-c
.c 200 .c
80'c
60
TABLE 54.5
200
80
"c
"c
200.c
-
Values of k for steel conduit, ducting and trunking as the protective conductor laterial olprotcctivc conductor
: :-. ronduit. .
du!^ling and tr
- .:neLl tnitial lentpc ltuae
:Clllocrlhr|i:
Irsulation nlatcrial 70
'c
90
"c
90.c
thermopiastic
thermoplastic
1l'r!'rnroseltinq
47
,+.1
5S
50
"c
160 "C
60
.c
t60.c
60.c 250.C
TABLE 54.6
-
Values of k for bare conductor where there is no risk of damage to any neighbouring material by the temperature indicated
NOTE:
The telnpemtures indicated are valid only where they do not impair the quality
ofthe connectioDs.
Conditiol1s
Material ofcotduclot
Visible and in
Normal conditions
Fic risk
lcstl-ic1ed areas 159
I38
Aluminiun
125
105
9l
Stecl
82
58
50
30'cl
l0'c
l0 "c
500'c 300.c
200
"c
150'c
200
.c
"c
200
"c
Copper
AssLrnred
initial tenlperature
Final ternperalure Coppcr corlductor
Alunri iun]
conductor'
Steel conductor
500
150 "C
150'c
543.1.4 Whele it is desired not to calculate the minimum cross-sectional area of a protective conductor in accordance with Regulatir:n 543. L3, the cross-sectional area rnay be detennined in accordance with Table 54.7. Where the application of Table 54.7 produces a non-standard size, a conductor having a larger standard crosssectional area shall be used.
.
TABLE 54.7
-
Minimum cross-sectional area of protective conductor in relation to the cross-sectional area of associated line conductor
C
ross ricclional alca
oflirrc
colrductor S
lvlininrLnr cross sectional area ofthe corr-cspondinS pR)tective concluctor-
lfthe plotective conductor ofthe same material as thc
If
the protective corductor is not ofthe sarne nraterial as
the line conductor (rnmr)
(1111nr)
s<
linc conductor
is
16
t6<s<35
s>35
where:
1qR
kl
is the value of k lbr the line conductor, selected from Table 43.1 in Chapter 43 according to the materials ofboth cor'rductor and insulation.
k,
is the vaiue
ofk lbl
the protective conductor', selected fl'onr lables 54.2 to 54.6, as applicablc.
Types of protective conductor 543.2 one or nlore of th' tbiilr$ ing: 543.2,1 A protective conductor ma"v col]sist of (i) A single-cote cable (ii) A corductot in a cable \a-ith insulated live conductors (iii) An insulated or bare conductor in a common ellclosurc (iv) Aiixed bare or insulated conducto or amotu ing of a cable (v) A nletai coYering, tbr exanrple' tile sheath' screen other encloswe or electrically (vi) A rnetai conduit' metaliic cable managei'nent systelr ol sYstem for condLlctors
continuous suppofi
543 2 6
(vii) an extaneous-conductive-pafi complying rvith Regulation or controlgear assembly or busbar ot frame of a lorv voltage switchgear enclosute metal a Whete 543,2.2 t-0"*t' ii shall satisfy the.following three requirements: such a way as truoking systefl is r.,,"d u' u p'ottci'i in construction or by suitable connection' (i) Its electrical continuity shall be assured' eitherorbyelectrochcmical deterioration to bc plotectcd agai"tt
t"tf.'u'itui "f''trlical
(ii)Itscross-sectionalateashailbeatleastequaltotlratresultingfromtheapplicationofRegulation543.l,or series *i,f., ifr. apiropriate part ofBS EN 61439 verified by test in a..orOun""
tap-offpoint'
protective conducto$ at eveq/ predetemined It shall pemlit the connection ofother pafis' or wires or other flexible metallic pipe' flexible ol ptiable conduit' support oil an pipe, gas A conductor' 543.2.3 as a protective iti ,r",r*r service, shall not be selected constructional parts ,uu1..t to nr.Jilunl.'ut^.ir*r
irr
(iii)
.l
543 2 1 and of crossdescribed in items (i) to (iv) of Regulation A protective conductor of the type s be ofcoppet' sectional arca [0 mtnr or less' shall a of a cable' in particular the sheath of sheath ffare protectlve a as used 543.2.5 Thc metal covering including the 1111r,*1ated' be may purposes and metal conduit, Jrrcti,ig fol ,nineral insulated caur", t*nting iJ (ii) of Regulation 543 2.2' "le"tri"al ,"ii!n", u*r,, *orirernents of items 1i) and corductor fbr the asro"iur.a .o.uir.irl;, be used as a extlaneous-conductive-pafi may 54323':n Regulation by prohibited as 543.2.6 Except the follorving requitemerts: ii"l"",ir. .""ar""r'if it s;tisflcs all connection' in such a way as to cither by construction or by suit:ble assured' be shall contrnuity (i) Electrical t}'"tical or electrociremical dcterioration
543.2.4
be protccted agalnst
'"tt.'initut'
(ii)Thecross-Sectionata,.a,hullb"utleastequaltothatresultillgflolntheapplicationofRegulation54].1.1 its removal shall be taken againsl
(iii) Unless compelsatory measures aIe providecl' precautiolls suitably adapted' (iu) t, hu. b..n aotsidered for such a ttse and' iflecessary' tntnking or ducting or the metal sheath conductor is lbrmed by metal conduit' plotective the Where 543.2.7 a separate protectlve ol each accessory shall be connected by
tenniral a'd,,or amor,rr of a cable. tlre ."rtr.,irg
in the lssociated box or other enclosure' conductot to atl eartf i"g t"'-l'ittoi intoiorated 543.2.8
Not usecl
eorr protective oro[eclrve cond*toi
-iy
circLrit whele the cllcnrt Except whele 543.2.9 543.2.9 11l:11"^1,::,"",T:Tl.:i::'i.li[:ii'jffi'.'ilXiTil: ,,,g n"uf air.r,,t shall also be mn in the the circuit prgtecti\.:.con1::to]^::-tn ling' rrrrE'l urs ofthe *^o*i"r{ or all 01 the conouctors "';."d ffi;;hing teminal at the ^.,"'".rthe cilcuit. origin of the circuit'
",-i"i-ir* lbmr ol a ring having both etrds conr 543.2.',10
shall oot be used as a PEN conductor A separate lretal enclosure for cable
543.3
of protective conductors Preservation of electrical continuity
s43.3.1
chemical deteriol.ation and protected against mechanical and Aprotective coudnctor shall be suitably
eiectrodynanric effccts'
543.3"2
except for inspection' testing and maintenance Every connection ard joint shall be accessible
orovided by Regulation 526'3
I
as
543.3.201
A protective conductor havrlg a cross-sectiorlal area Llp to and including 6 rnurr shall be protected throughout by a cove|ing at leasl equivalcut to that plovided by the insulation of a single cole rron-sheathed cable ofappropriate size having a voltage latirlg ofat least 450/750 \2. except lbr the lbllowing:
(i) (ii)
A protectiv(] conductor forning parl of a nlultiool e cable
A netal couduit. metallic cable malagenrert systelD or other elclosure or electrically co[tir]uous supporl systerr tbr conductols. rvlrere lsecl rs
a
protective conductol.
Whele the sheath of a cablc' incorporatilg alt rurirtsirlated prolcctive corlductor of cross-sectional alea up to atrd including 6 urnr is reuroved adjacent to.joiuts and ternilations. the protective colductol shall be pr-otected by insulating sleeving complying with BS EN 60684 selies.
543.3.3.101 No switchirg device shali be irseted i[
(i) (ii) (iii) (iv)
as
a protective conductor, except:
pemitted by Regulation 537.1.5
a multipole, linked switching in whjch the plotective corlductor cilcuit is not interupted before the live conductors and is re-established lot later than wheu the liYe conductors are recornected
a switching device interlocked with a multipole. linked switching device i[serted in the live conducto$ such that the protective conductor circuit shall not be interrupted before the live couductors ald shall be re-established lot later than when the live coodLicto$ are reconnected. or multipole plug-in device in which the plotective conductol circuit shall not be intenupted belble the live conductors and shall be le-established not later thau whetr the live conductors are reconnected.
a
Switchilg devices provided in accordance with (i). (ii), (iii) and (iv) shall meet the requirerreuts olChapter 46 and Section 537 fol a device tbr isolation. Joints for test purposes that can be discoruected o11ly by the use ofa tool rray be insefied in a proteqtive conductor.
543"3,4
Where electrical eartll rnonitoring is used. rur dedicated devices (e.9. operatitrg sensors. coils) shall be connected in series \\,ilh tlle protective cotductor (see BS 4444).
543.3.5 An exposed-conductive-part of eqLripment shall 1lot be used to lbrm a protectivc conductor fol other equipment except as provided by Regulations 543.2.I . 543.2.2 and 543.2.5. 543.3.6 543.4 543.4.1 NOTE:
Eve$/joiut in nretallic couduit
sha1l be
mechanically and electrically continuous.
Combined protective and neutral (PEN) conductors PEN corductor shall not be Lrsed witlriu au inslallation except as pemitted by Regulation 541.4.2.
Rcgulation 8(4) ol dre Elcctricity Safity. Quality ancl Corrtinuity Regulations (ESQCR) prohibits thc usc of PEN conductors irl corls lncrs' ilrstallations
543.4.2 The provisions ofRcgulations 543.4.3 to 54J..1.8 rlray bc applied only: (i) whcre any necessary autllorization i'or us!'of a PEN conductor has been obtaincd
and where the installation
complies with the cotditions lbr that authodzation. or
(ii) where the installation is supplied by 11o (
a privately o\\,red transfolmer or conveftor in such a way that there is metallic connection (except fbr the eanhing conllection) with the distributol's networ-k, cu
iii) whele the supply is obtained flonl a plivale gerreratiug plant.
543.4.3 If, fi-orn any poillt ofthe instailation. the neut|al aDd protective functions are plovided by separate conductors, those corlductols shall lrot thel1 be reco[rected together bcyond that point. At the point of sepalation. separate tenninals ol bars shall be plovided 1br the protective and [eutral conductols. The PEN conductor shall be connected to the te ninals or bar intended for d]e protective earthil'lg conductor and the neLLtrai conductor. The corductarce ofthe teurinal link or bar shall be not less than that specilied in Regulation 543.4.5. 543,4,4
The outer conductor of a concentric cable shall rot be coluron to nrore than one cilcuit. This ola trviu or nulticr-rre cable to sel've a nu[]ber ofpoints contained withiu one
requirernent does not preclude the use
final circuit.
543.4.5 The conductance ofthe outer conductor ot a concentric cable (fleasuled at a ten]pelatue of20 "C) shall: (i) for a single-corc cable. be not less thal that ofthe intenul conductor (ii) fbr a multicore cable serving a r:urnber of points cortained withirr one linal circuit or having the intemal conductors connected in parallel. bc no1 lcss than that ol the internal conductors connected in parallel.
200
- -::.: 'il a rcrmination. the continuiq of to an\ r'11.',:-' .':.: :.rr sealing arrd clalrping tl]e oritel'
ola conccntt:;
'-:--
by'' a conductot additional corlductor. The corductatrce ofthe additiorlal conductot shall be noi tin thc outer colductol.
l:.,
543.4.6
At
er
er.l ioint ir't tl'te outcr conductor
lhat.joint shall be su1'rpletnented
:
.; specilied in Regulatiott 543.4.5
No means ofisolatiol.t or switching shall be inserted in the outer conductor of
543.4.7
a
concentric cable.
Excepting a cable to BS EN 60702-1 installed in accordance \\'ith th!' manuthctlrer's instructiol]s. pEN conductor olevery cable shall be insulated or have ar insulating cor cring .uitable ibr the highest voltage the to which it uray be subjected.
543.4.8
I
543.4.201
For
a
fixed installation.
conductor ofa cabte not subject to flexing and har ing a cross-sectional area mmr for aluminium may serve as a PEN conductor pro\ ided thal the part of
a
not less than l0 mrrr lor copper or l6 the installation concemed is not supplied through an RCD.
543.5 543,5,1
Earthing arrangements for combined protective and functional purposes Where earthing for combined plotective and filnctional puryoses is tequiled. tlte requirements firt'
protective mcasulcs shall take precedcnce
Earthing arrangements for protective purposes
543.6
where overcuffent protective devices are used for fault protectio1r. the protective conductor shall be incel'pomtcd ill tl']e same wi ng system as the live conductors or in their immediate proximity'
543.6.1 I
I
543.7
Earthing requirements for the installation of equipment having high protective conductor currents
543.7 .1
General
543,7.1.20'l Equipmcnt having a protective conductor curent exceeding 3.5 lllA bul l'Iot exceeding 10 mA- shall or bc L'ither penranently connected to the fixed wifitlg ofthe installation \\,itl']out the use ofa plug and socket-outlet 60309-2' with BS EN connccted by Ineans ofa plug and sockeloutlet complying 543,7,1.202 Equiprrent having a plotcclivc conductol. current exceeding l0 rrA shall
bl
one
(i) 1ii)
be
collectcd to the supply
olthc following tnethods: permal1ently corrnected to the wiring ofthe installation, with the protectivc colductor selected in accordancc with Rcgulation 543.7.1 .203. The pemanent connection to the wiling lnay be by nrcans of a flexiblc cable A flexible cablc wilh a plug and socket-outlet conplying with BS EN 60309-2. provided that either:
(a) the protective conductor ofthe associated flexible cable is ofa cross-sectional aleit not less than 2.5rrmr for plugs rated at 16 A and llot less tllan 4 mmr fot plugs t'ated ah()vc l6 A- ot (b) the protective conductor olthe associated flexible cable is of The lir're
(iii)
not less than that of
conductor
A protective conductor complying with Section 543 with an eadh lnonitoring system to BS 4444 installed which, in the eYent ola continLrity 1ault occurring supply to the equiPmert.
t'
a cross-scctioltal area
i1,]
the plotective colductor. auto)natically disconnects d]e
543.7.1.203 The rviring of every final circuit ard distribution circuit irtended to supply one or |nore items of :quipment. such that the lotal protective conductor cunent is likely to excced l0 lnA. shall have a high inregrity :iorective corlnection complying with o:re'or more ofthe lollowing:
(i) i
ii)
iii)
A sirgle protective condlLctol'having a cross-sectiolal area ofnot less tlran l0 tnn2. complying with the requirerrents ofRegulations 543 2 and 543.3 A single copper protective conductol. having a ctoss-sectional area of not less than 4 tnmr. complyitlg with ii,c r.equi.ements ofRegulations 543.2 and 543.3, the plotective conductor being enclosed to provide additional protection against uechanical damage, for example. within a flexible conduit Two ildividual plotective conductols, each complying with the requiletnellts of section 543. The two pr.otective conductors may bc ofditlerent types, e.g. a lnetal conduit togethel with an additional conductol' of a cable enclosed in tlle same colduii.
rire the two indivirtual protective conductors are both incoryorated in a uulticole cable. the total cross-sectioDal l0 1nlr1r. One of the prote.'tivc ---'l of all the conducton including thc'live conductors shall be not less than in the const:uction of incorporatid sclecn wire braid annour or sheath, th.,',',.tullia - :,luctors may be fbrmed by -. iable and couplying r,vith Regulation 5'13.2.5 .,.
201
(iv)
An eafih monitoling systelr to BS 4444 may be installed which, in theeventofa continuity fault occurring ilt the protective couductol, automatically disconnects the supply to the equipment
(v)
Connection ofthe equipDrert to the supply by means ofa double-wound transformer ol equivalent unit, such as a motor-altenator set. the prctective conductor ofthe illcoming supply being connected to the exposedcondlLctive-parts ofthe equiprnent and fo a point ofthe secondary winding ofthe h?nsfoflner ol equivalent device. The protecrive conductor(s) between the equipmeflt and the tr-anstbrmer or equivalent device shall comply with one ofrhe an'argemerts described in (i) to (iv) above.
are used in accordance with Regulation 543.7.1.203(iii), the ends protective terminated independently ofeach other at all connection poillts throughout the conductors shall be ofthe julction and socket-outlets. This requires an accessory to be provided with circuit. e.g. the distlibution board, boxes teminals. two sepamte carth
543,7,1,204 Where two protective conductors
543.7.1-205 At the distribution boald inibmation shall be provided indicating those circuits having a high protcctive conductor curent. This informatjon shall be positioned so as to be visible to a person who is modifying or extendiug the circuit. 543.7
.2
Socket-outlet final circuits
543.7.2.201 For a tinal circuit with a number of socket-outlets or connection units intended to supply two or nore items ofequipment, where it is know1l or reasonably to be expected that the total plotective conductor current in uonnal service will exceed l0 urA. the circuit shall be provided with a high integrity protective conductor courrection con'rplying with the requirements ofRegulation 543.7.1. The ibllowing arangements ofthe final circuit are acceptable:
(i) 1ii)
A rfug final circuit with a ring protective conductor Spurs, if provided, require high integrity protective conductor corulectiots complying with the requirements of Regulation 543.7.1 A radial final circLdt with a single protective conductol': (a) the protective corductor being connected
(b) a
as a
ring, or
separate protective conductor being provided at the
final socket-outlet by connectiot'r to the netal
conduit ol ducting. or moLe sinilar radial circuits supply socket-outlets i[ adjacent areas and are fed fiom thc same distribution board, have identical means of short-circuit and overcurrelt protection and circuit protective conductoLs of the same cross-sectional area, then a second protective conductor may be provided at the final socket-outlet on one circuit by comection to the plotective conductor ofthe adjacent
(c) where two or
cilcuit
(iii) 544 544.1
Other circuits complyirg raitJr dre requirements of Regulation 543.7.1.
PROTECTIVE BONDING CONDUCTORS
Main protective bonding conductors
544.1.'l Except where PME conditions apply, a main protective bonding conductor shall have a crosssectional alea tlot less than half the closs-sectional alea required for the earthing conductor of the installatiol al1d not less thar 6 mmr. The uoss-sectiolal area need not exceed 25 mm] if the bonding conductor is of copper or a closs-sectional area allbrding equivalent conductance in other metals. Except tbl highway power supplies and street funiture, where PME conditions apply the main protective bonding conductor shall be selected in accordance with the PEN conductor ofthe supply and Table 54.8. Where an ilstallation has lnore than one source ofsupply to which PME conditions apply, a main protective bonding conductol shall be selected accor-ding to the largest PEN conductor ofthe supply.
202
TABLE 54.8 Minimum cross-sectional area of the main protectjve bonding conductor in relation to the PEN conductor of the supply Local distributor's lll]tlvork conditions may r-equie a largcr conducir,i
Copper equivalent cross-sectional ar.ea ofthe PEN
conductor 35 mmr or less
olthe main
bonding conductor 10
mml
over 35 mmr up to 50 nrmr
I
ovel 50 mnl] up to 95 mlnl
25 mrnl
over 95 mmr up to 150 mml
35 mn-rr
over
*
Minimunr copper equir alent* cross-sectional area
150
runl
6 n.rm:
50 mt'r:
The l't'liniu'tuu copper equivalelt closs-sectional area is given by a copper bonding conductor ofthe tabulated cross-scctioral arca or a bonding conductor ofanother metal affor.ding equivalent conductance.
544.'1.2 Tlre main protective bonding couection to any extraneous-conductive-paft such as gas, water or othcr metallic pipework or service shall be rnade as near as practicable to the point of eDtry of that part into the premises. Where there is a meter, isoJation point or urion, the connection shall be made to the consumer's hard metal pipework and befote any branch pipework. Wherc pmcticable the connection shall be made within 600 mm ofthe meter outlet union or at the point of enn), to the building ifthe meter is exterual.
.:, :_.1
!'f -.ll
544,2
Supplementarybondingconductors
544.2'1 A supplementary bonding conductor connecting two exposed-conductive-parts shalt have a conductance, if sheathed ot otherwisc provided with mechanical protection, not less than that of the smaller protective colductor connected to the exposed-conductive-parts. Ifmechanical protection is not provided, its crosssectional area shall be not less than ,1 mmr. iiirl
544.2.2 A supplementaty bonding conductor connecting an exposed-conductive-pa1t to an exfaneousconductive-paft shall have a conductance, if sheathed or otherwise provided with mechanical protection, not less thal halfthat ofthe protective conductor conlrected to tlre exposcd-conductive-part. Ifmechanical protection is not provided. its cross-sectional alea shall be uot less than 4 mmr.
ihe
:;uit
:
tre
544.2.3 A supplelnentary bonding conductor connecting two extraneous-conductive-parts shall have a crosssectional area r'tot less tha[ 2.5 rnmr if sheathed or otherwise provided with mechanical protection or 4 nm, if rrechanical protection is not provided, except that where one ofthe extraneous-conductive-pafts is connected to an exposed-conductive-par1 ir colnpliance with Regulation 544.2.2. tl1at regulation shall apply also to the condrLctor connecting the two c\ tra neous-conJ uc rive-pa m..
raL'l]t
544.2.4 croSs-
n
and
,.r
or
L
a
iLiing
Except where Regr"rlation 544.2.5 applies, supplementary bonding shall be provided
by
a
supplementary cotlductor, a conductive part ofa pennalrent and reliable nature, or by a conrbination ofthese.
544'2.5 Where supplenrentary bonding is to be applied to a ilxed appliance which is supplied via a shorl length of flexible cable iiom an adjacent connection unit or other accessory, incorporating a flex outlet, the circuit protective conductor within the flexible cablc shall be dcemed to provide the suppleme[tary bonding connection to the exposed-conductive-pafis ofthe appliance. fiom the earthing terminal in the connection unit or other accessory.
I I I
CHAPTER 55 OTHER EQUIPMENT CONTENTS 550.1
Scope
551
LOW VOLTAGE GENERATING SETS
551
Scope
.1
551 .2
551.3 c5 t .J.
I
General requirements Protective measure: Extra-low voltage provided by SELV or PELV Additional requirements for SELV and PELV
551.4
Fault protection
551.4.3
Protection by automatic disconnection of supply Additional requirements for protection by automatic disconnection where Protection against overcurreni Additional requirements for installations where...
551.4.4 551.5 551.6 551.8
Additional requirements for installations where... Requirements for installations incorporaiing stationary batteries
552
ROTATING MACHINES
552.1
Rotating machines
553
ACCESSORIES
553.1
Plugs and socket-outlets
553.2
Cable couplers
554
CURRENT.USING EQUIPMENT Electrode water heaters and boilers
551 .7
554.1
554.2 554.3 554.4
Heating conductors and cables
555
TRANSFORMERS
555.1
Autotransformers and step-up transformers
557
AUXILIARY CIRCUITS
557 .1
Scope
557 .3
Requirements for auxiliary circuits
557.3.1
General
557.3.201
Control circuits Power supply for auxiliary circuits dependent on the main circuit Auxiliary circuit supplied by an independent source
557.3.2 557.3.3 557.3.4
Auxiliary circuits with or without connection to earth Power supplies for auxiliary circuits
557.3.6
Protective measures Characteristics of cables and conductors
557 .4 557 .4.1
lvlinimum cross-sectional areas Requirements for auxiliary circuits used for measurement
557.5.1
General
557.5.2 557.5.3
Auxiliary circuits for direct measurement of electrical quantiiies Auxiliary circuits for measurement of electrical quantities via a transformer
557 .6
Functional considerations
557.6.1
Voltage supply
557 .6.2
557 .6.4
Quality of signals depending on the cable characteristics Measures to avoid the loss of functionality Current-limiting signal outputs
557.6.5
Connection to the main circuit
557.6.3
L-=-
Heaters for liquids or other substances having immersed heating elements Water heaters having immersed and uninsulated heating elements
557.6.6
Plug-in connections
559
LUMINAIRES AND LIGHTING INSTALLATIONS
559.1
Scope
559.3
General requirements for installations effects Protection of the surroundings against thermal
559.4 559.4.1
559.5 559.5.1
559.5.2 559.5.3 559.5.4 559.5.5 559.5.6 559.6 559.7 559.8 559.9 559.'10
General Wiring systems Connection to ihe fixed wiring Fixing of luminaires Through wiring Devices for connection of luminaires to the supply Groups of luminaires within luminaires Protection against heat and UV radiation effects lndependent lamp controlgear, e g ballasts Compensation caPacitors for luminaires Protection against electric shock for display stands StroboscoPic effect Ground-recessed luminaires
CHAPTER 55 OTHER EQUIPMENT 550.1
Scope
Chapter 55 specifies requirements and recommendations for the selection and erection of low voltage electrical equipment not covered by other parts ofBS 7671 except Pafi 7, intended to be pan ofthe fixed installation.
551 551.1
LOWVOLTAGE GENERATING SETS Scope
This scction applies to low voltage and extra-low vo)tage installations which incorporate generating sets i[tended to supply, either continuously or occasionally, all or part ofthe installation. Reqr.rirements are included 1br installations with the following supply affargernerlts:
(i) (ii) (iii) (iv)
Supply to an installatiol which is not conltected to a system for
dist bution ofelectlicity to the public
Supply to an iustallation as an altemative to a system for distribution ofelectricity to the public Supply to ao instaliation in palallel with a system for distributiou ofeleotricity to the public Appropriate conbirrations ofthe above.
This section does not apply to sell'-contained items of extralow voltage electrical equiprnent which incorporate both the source of erergy aud the e[ergy-using load and for which a specific product standard exists that includes thc lequrreurenl. lbl elcctrrtal saletl.
NOTE:
Whcre a gcncratiDg set with an output not exceedirg l6 A is to be connected in parallelwith a system fot distribution ol electiicity to the public. procedures for infoflning the electricity distributor are given in the Electricity Sattty, Quality and Continuity Rcgulations (ESQCR). tn addition to the ESQCR requirements, where a gelerating set with an outpui cxceeding 16 A is to be connected in parallel with a system for distribution of electricity to the public, requir-eDrents of the electricity distributor should be ascertained beforc thc generating set is connected. Requirernents ofthe dishibutor for thc conncction ofunits ratcd up to 16 A are given in BS EN 50,138.
551.1.1 Generating sets with the fbllowing power sources are considered: (i) Cornbustiolengines (ii) Turbines (iii) Electric Dotors (iv) Photovoltaiccells (v) Electrochemicalaccurnulato$ (vi) Other suitable sources. 551.1,2 Generating sets with the following electdcal chamcteristics are considered: (i) Mains-excited and separatcly excited synclnonous generators (ii) Mains-excited and self-excited asynchronous generators (iii) Mains-commutated and sell'-conmutated static convefiors with or without bypass facilities. 551.1.3 The use of generating sets for the following purposes is considered: (i) Supply to penlanent installations {iit Supply lo tcnrporaq installations (iii) Supply to mobile equiplnent which is not cornected to a permanert fixed installation (iv) Supply to mobile units (Section 717 also applies). 551.2
General requirements
55'1,2,1
The means ofexcitation and commutation shall be appropriate for the intended use ofthe generating set and thc salety and proper functioning of other sources of supply shall not be impaired by the generating set.
551,2.2
-lhe
prospective shofi-circuit cuuent and prospective eadh fault curent shall be assessed for each source ofsupply or coflrbinatiorr ofsources which can operate independently ofother soulces ol combinations. The
shot-circuit mting of protective devices within the installatior.r and, where appropriate, connepted to a systen fot' distribution ol electdcity to the prrblic, shall not be exceeded for any of the intended nethods of operation of the sources.
206
551,2,3
Where the genercting set is intended to provide a suppl) Io an installaiion \\hich is not connected to a systeln fordisi butiol of elcctt'icity to the public or to pl ovide a supp1l as a s"r :t;hed altemati\ e to such a system, the capacity arld opemting characteristics of the generating set shall be .ucl ihri i:rger or darrage to equipment cloes l-Iot arise aficr the couection or disconnectiolr of any intended load a. a re.u]i tiihe deriation ofthe voltage or frequency frorn the intended operating range. Mears shall be prorided io automaiicall\ disconnect such pafts of the installation as may be necessaly ifthe capacity ofthe generating sel i5 erceeded. NOTE 1: Consicler.ation shoulcl be given to the intended duty cycle arld size ol indi\ iduai ;o:,r:cr:d loads as a proponion ofihe capacity olthe generating set and to the startng cllamctelistics ofan\ conneci.d elsa:ic nlotors. NOTE 2: Considelation slrould bc given to thc power f'actor speciied tbr protecti\
e de\
i..s
::r
th. inslallation.
NOTE 3: The installalion ofa genemtil1g set rvithin an existing building or installation me. ;hange the conditioDs olextemal inllucnce for-the installatior (see Part 3). for e\ample by the irltroduction ol Ino\ ing prni. parts at high te perature or by the prescrce
,2,4
offlan
rable fluids alrd noxious gascs. etc.
ision for isolation shall rneet tlre requir ernents of Chapter combination of sources of supply. 551
Pr.ov
551.3 551.3.1
.16
and Section
5
i 7 for each source or
Protective measure: Extra-low voltage provided by SELV or PELV Additional requirements for SELV and PELV where the installation is supplied from more than one source
Whete a SELV or PELV system may be supplied by more than one source, the requirements of Regulation '114.3 shall apply to each source. wlrere one or rnore of the sources is earthed, the requirements for PELV systenls in Regulation 414.4 shall apply.
If one or more of the sources
t
of Regulation 414.3, the system shall be treated
as a
FELV system ard thc requiremcnts ofRegulation 411.7 shall apply.
I
.ll
does t'tot meet the requirerrents
I I
Whcre it is necessary to lnaintain thc supply to an extralow voltage system following the loss of one or mot.e soLrrces of supply. each source of supply or cornbination of sources of supply which can operate independently of other sources or combinations shall be capable of supplying the intended load of the extra-low voltage systen'1. Provisions shall bc rradc so that loss ofthe low voltagc supply to an extra-low voltage soutce does not lead to dangcr or damage to other cxtra-low voltagc cquipment.
551.3.2
a.
NOTE:
Such provisions may bc lecessary in supplies for safety seNices (see Chapter 56).
551.4 551.4.1
Fault protection
Fault protection shali be providcd for the irstallation in Iespect of each source of supply or combination ofsources ofsupply that can operate indepeldently ofother sources or con]binations ofsources. TIte t'ault protective provisions shall be selected or precautiors shall be taken so that where fault protective provisions are achieved in different ways within the same installation or pafi ofa[ ilstallation according to the active sources of supply. no iufluence shall occul ol condjtions a se that could impair the effectiveness of the fault protective
plovisions.
NOTE:
This rnight.lbl. example. requile the use ofa lmnsfbnnerproviding electrical separation bet\\'een palls ofthe irrstallalion usirlg diflerent earthing systerl]s.
551-4.2
The generating set shall be connected so that any provision withir the installalion for protection by RCDs in accotdance witb Chapter 41 remains effective 1br every intelded combination ofsources ofsupply.
NOTE:
Conrlecliorl 01'livc parts ofthe generator u'ith Eallh may affect the protective measule
551.4.3
Protection by automatic disconnection of supply
.4.3,1 Protection by automatic disconnection of supply shall be provided in accordance except as modified for particular cases by Regulation 551.4.3.2, 55 1.4.3.3 or 551 .4 4. 551
551.4.3.2 Additional requirements for installations
\
ith Section
'11
I
.
where the generating set provides a
switched altemative to system for distribution ofelectricity to the public (standby systems)
:..
551,4,3.2.1 Protectiol by autolnatic discornection of supply shall not rel] upon Ih. .-..nnection to tfie eanlI.d point oftlte systenl lbr distr ibution ofelectricity to the public rvhen the gerlerator is optr:Irrg as e :$ itched aitenrriir e to a TN systern. A suitable means ofearthing shall bc provided.
Tire
:.:l lot : -.i tlre
,a ---
551.4.3.3 Additional requirements for installations incorporating static convertors 551'4.3,3,'l
Wherc lault protectiol fot palts of thc installatior supplied by the static converlor relies upon the of the bypass srvitch and the operation of prolective devices on the supply side of thc bypass switclr is not within the time required by Section 4ll, supplernentary equiporenlial bonding shall be proviclecl between simultaleor"Lsly accessible exposed-cordrLctive-parts and extmrleous-conduclive-pafis otr the ]oad side of the static couveflor in accordance rvith Regulatittn 4l 5.2. aLLtoll]atic closure
The resistance (R) of the supplerlcntary proteclivc bondirg condLrctor- required betwecn simultaneously accessible cxposed-collductive-parts altd extrancorrs-collducti\.c,l]afis shall f'ulfil the lbllowing condition: R < 50/t" where: is the maxilr]uln eafh tlult currelt which can be supplied by the static convertol whelt the bypass switch is closed.
I"
NOTE:
Where such equiprlcnr is intendcd to operute requiremenls ofReglLlation 551.7 also a|p1y.
ir
parallel wiril a systcrr tbr clistribution ofelectlicity to rhc public. the
551.4.9.3.2 PrecalLtions shall be taken ot ecluipureut shall be selectecl so that the conect operatiolt olplotective devices is not impaired by DC cuu-ents gclterared by a static convcfior or by the ptesence of filtcr.s. 551.4.3.3.3 A means ofisolation shall be installed ort both sides ofa static cotrveftor. This requirement does not apply on the power source side ofa slatic converLor wlrich is intcgrated in the saure enclosul'e as the power source.
551.4.4 Additional requirements for
protection by automatic disconnection where the installation and generating set are not permanently fixed
This regulation applies to poflable generatitg sets and to gel'rerating sets which are intended ro be tnoved to unspecified locations 1br tempomry or sllort tcllll use. Such genelatilg sets rray be pafl of an ilstal]atiou which is subject to sirrilar use. fhis regulation does not appl), to penltatlctll llxed itstallations.
NOTE:
For suitablc conncctjon
a
-aogenenrs see IIS LN 60309 senes.
55'1.4.4.1 Between separate iterns of equrpnrent. protective conductols slrall be provided which are pan of a suitable cable and which corrply with Table 54.7. All protective conductors shali cornply wirh Chaptcr'54.
55'1.4.4'2 In a TN, TT or lT systerr, every lilal circuit shall be provided with additiolal prorcclion by rreans ofan RCD having the characte stics specified il llegulation 415.1. NOTE:
ll1 an IT system. an RCD nray not
operate nlcss one ot the catth ihults
is on a part
oftlte system on the slrpply
side
of
the device.
Protection against overcurrent
551.5
551.5.'t Where overcurrcnt plotectior ofthe ger)erating set is rccluiled, it shall be located as near as practicable to the generator tenninals.
NOTE:
The corltribution to the prospective sholt-cilcLrit less than thc
cullert by a gencrating set nray be rinlc-dcpendent conlibution madc by a syst.ul lbl distributron ol electrici!y to thc public.
and
nuy
be much
551.5,2 Where a generating set is iDtended to opelatc iu parallel rvith a system tbr distriburion of electricity to the public, or wltere two or'nore gellcratilg sets ll1ay opctate in palallel, circulating harmonic curents shall be linited so that the thennal rating ofconductors is rot exceeded. The effects ofcirculating harmonic cuirents tnay be Iinited by one or morc ofthe fbllowing:
(i) (ii) (iii)
The sclectiol ofgenerating sets with cornpensatcd wirdings The provision ofa suirable irrpedance in thc connection to the generator star points The plovisior oiswitches which inten'tipt the circulatory circuit but which are interlocked so rhat at all tinles 1'au1t
t (vt
(ir
flre p[ovisirrrr ol
lill(rirc
c,lllipr]re
Othel srritable rncarr:.
NOTE:
248
protection is not intpaired
Consideration should bc given to the ntaximum voltase which may bc plodLrced across an irlpedance connected to linlit circulaling hannonic curel]ls
Additional requirements for installations where the generating set provides a supply
551.6
as a switched alternative to the system for distribution of electricity to the public
(standby systems) 551.6.1
Precautions cornplying with the relevant requirements of Chapter 46 and Section 537 for isolation shall be taken so that the generator camot opemte in parallel with the sysiem for distribution of electricity to the public. Suitable precautions may include one or more olthe following:
(i)
An electrical, mechanical or electromechanical interlock between the operating urechanisms or control circuits ofthe changeover switching devices
(ii) A system of locks with a single transferable key (iii) A three-positiqn break-before-make changeover switch (iv) An automatic changeover switching device with a suitable interlock (v) Other means providing equivalent security of operation. 551.6.2 For a TN-S system where the neutral is not isolated, any RCD shall be positioned to avoid incorrect operation due to the existence of any parallel neutral-eardr path.
NOTE: It may be desirable
in a TN system to disconnect the neutml ofthe installation front the neutml or PEN ofthe system for distribution of electricity to the public to avoid disturbances such as induced voltage surges caused by lightning.
Additional requirements for installations where the generating set may operate in parallel with other sources including systems for distribution of electricity to the
551.7
I
public
When a generating set is used as an additional source of supply in pamllel with a[other source, both
551 .7 .1
olthe following conditions shall be tutfilled:
I
:a
(i)
Protection against thermal effccts in accordance with Chapter 42 and protection against overcurrent in accordance with Chapter 43 shall remain effective in all situations
(ii)
Where an RCD is providing additional protection in accordance with Regulation 415.1 for a cilcuit connectilg the generator set to the installation, the RCD shall disconnect all live conductors, including the neutral conductor.
551.7
.2
A genentirg set used as an additional source of supply in parallel with another source shall be installed;
ofall the overcurrent protective devices for the final circuits ofthe installation, or olall the overcurent protective devices for a firal circuit ofthe iNtallation, but in this case all the
on the supply side on the load side
following additional requirements shall be fullilled:
(i)
The conductors ofthe
firal circuit shall
meet the following requirement:
I.>1,,+ls where:
[, is the cuffent-carrying capacity ofthe final circuit conductors I,,
is the lated cuffent ofthe protective device ofthe final circuit
Ig is the rated
output cufl'ent ofthe generating set
(ir) A generating set shall not be connected to
a
flnal circuit by mcans ofa plug and socket-outlet
(iii) The line and neutral conductors of the fina1 circuit and ofthe generating
set shall not be connected to
Earth Unless the device providing automatic disconnection ofthe final circuit in accordance with Regulation 411.3.2 disconnects the line and neutral conducto$. it shall be verified that the combination of the disconnection time ofthe protective device for the final circuit and the time taken for the output voltage of the generating set to reduce to 50 V or less is not greater than the disconnection time required by Regulation 4l 1.1.2 lor the final circuit.
-::.'gulationdoesnotapplytoanunintenuptiblepowersupplyprovidedtosupplyspecificitemsofcunent-using -, .. :ment within the final circuit to which it is connected.
.7.3
:5'1 h selecting and using a gereratirg set to mn in parallel with the systerr lor distibution ofelectricity : 'e public. care shall be taken to aYoid ad|erse effects 10 that system and to other jnstallations in respect of .,. ir l'actor, voltage changes, harmonic distotjon. unbalance. stafting, synchronizinu or voltage fluctualion effects. ' iere synchlonization is necessaqr. the use of an alrtolnatic synchronizilg system \\ticlt considers frequency. -
-,.e and voltage is to be prefered.
551.7.4
Means ofautomatic switching shall be provided to disconnect the generating set from the system for ofelectdcity to the public in the event ofloss ofthat supply or deviation ofthe voltage or frequency at distribution the supply terminals from declared values.
For a genenting set with an output exceeding 16 A, the type of protection and the sensitivity and operating times depend upon the protection ofthe system for distribution of electricity to the public and the number of generating sets connected and sha1l be agreed by the distributor. For a generating set with an output not exceeding 16 A, the settings shall conply with BS EN 50438.
In the case ol the presence of a static convefor, the meani of switching shall be provided on the load side of the static convertor
551.7.5
Means shall be provided to prevent the connection ofa generating set to the system for distribution of electricity to the public in the event of loss ofthat supply or deviation ofthe voltage or frequency at the supply teminals from values required by Regulation 551.7.4.
NOTE:
For a generating set with ail output not exceeding 16 A intended to opemte in parallel with a system for distributiorl electlicity to the public the requirements are given in BS EN 50438.
of
551.7.6
Means shall be provided to enable the generating set to be isolated from the system for distribution set with an output exceeding 16 A, the accessibility of this means of isolation shall colnpty with national rules and distribution system operator requirements. For a generating set with ar output not exceeding 16 A, the accessibility of this means of isolation shall comply with BS EN 50438.
of eleitricity to the public. For a generating
551.7.7 Where a generating set may operate as a switched altemative to the system for distribution electricity to the public, the installation shall also comply with Regulation 551.6. Requirements for installations incorporating stationary batteries
551.8
551.8.1 NOTE:
of
Stationary batteries shall be installed so that they are accessible only to skilled or instructed persons.
This generally requires the batteiy to be installed in a secure location or, for smaller batteries, a secure enclosure.
The location or enclogure shall be adequately ventilated.
551-8.2
Batteryionnections shal) have basic protection by insulation or enclosutes or shall be arranged so that two bare conductive pafis having between them a potentiat difference exceeding 120 volts cannot be inadvefiently touched simultaneously.
552 NOTE:
ROTATING MACHINES See also Regulation ,163.3
552.1 552.1.1
Motor control.
Rotating machines A1l equipment, including cable, ofevery circuit carrying the stafiing, accelerating and load curents
of a motor shall be suitable for a curent at least equal to the full-load current rating of the motor when rated in accordance with the appropriate British or Harmonized Standard. Where the motor is intended for intermittent duty and for {iequent stafiing and stopping, account shall be taken of any cun.tulative effects of the starting or bruking cufients upon the ten'iperature se ofthe equipment ofthe circuit.
552.1.2 Every elect c motor having a rating exceeding 0.37 kW shall be provided with control equipment incorporating means of protection against overload of the motor This requirement does not apply to a motor ircorpomted in an item ofcunent-using equipment complying as a whole with an appropdate British or Harmonized Standard.
552.1.3
Except where failule to startafterab ef intemrption would be likely to cause greater danger, eYery motor shall be provided with means to prevent automatic rcstarting after a stoppage due to a drop in voltage or failure of supply, where unexpected restafting ofthe motor might cause danger This requirement does not preclude arangenents for starting a motor at intervals by an automatic control device, where other adequate precautions are taken against danger from unexpected restarting.
210
ACCESSORIES
553
Plugs and socket-outlets
553.1
553.1.1 Evely plug and socket-outlet shall comply with all the requirements of items (i) and (ii) betow and. in addition, with the appropriate requirements ofRegulations 553.1.2 to 553.2.2:
(i)
Except fbr SELV circuits, it shall not be possible for any pin of a plug to make contact with any live conract ofits associated socket-outlet while any other pin ofthe plug is completely exposed
(ii)
It shall not be possible for any piu of a plug to make contact with any live contact ofany socket-outlet within the same installation other than the type of sockeGoutlet for which the plug is designed.
553.1.2
Except for SELV or a special circuit frorr Regulation 553.1 .5, every plug and socket-outlet shall be ofthe non-reversible type, with prcvision for the connection of a protective conductor
553.1.3
Except where Regulation 553.1.5 applies, in a low voltage circuit every plug and socket-outlet shall confomr with the applicable British Standard listed in Table 55.1.
rrl
TABLE 55.1 Plugs and socket-outlets for low voltage circuits
!)1',l
..i nh
of
Type of plug and socket-outlet
Applicable British Standard
Fused plugs and shuttcred socket-outlets, 2-po1e and earth, fol AC
BS I363 (tuses to BS 1362)
Plugs, fused or non-fused, and socket-outlets, 2-pole and ealth and socket-outlets !rns.
industrial
2, 5, 15,30
BS 546 (fuses, ifany, to BS 646)
t6,32, 63, 12s
BS EN 60309-2
553.1.201 Every socket-outlet for household and similar use shall be of the shuttered type and, for an AC installation, shall preferably be ofa tlpe complying with BS 1363.
553.1.5
A plug and socket-outlet not complying with BS 1363, BS 546 or BS EN 60309-2, may be used in single-phase AC or two-wire DC circuits operating at a nominal voltage not exceeding 250 volts for:
r that .3nti-v
(i)
the connection of an electric clock, provided that the plug and socket-outlet are designed specifically for that purpose, and that each plug incorporates a fuse of rating not exceeding 3 amperes complying with BS 646 or BS 1362 as appropriate
(ii)
the connection of an electric shaver, provided that the socket-outlet is either incorporated in a shaver supply unit complying with BS EN 61558-2-5 or is a type complying with BS 4573
(iii) [rrents
circuit having special characteristics such that danger would otherwise arise or it is necessary to distinguish the function ofthe circuit.
a
braking
553,1.6 A socket-outlet on a wall or similar strxcture shall be mounted at a height above the floor or any rvorking surface to miniurize the risk of mechanical damage to the socket-outlet or to an associated plug and its flexible cable which might be caused during inserlion, use or with&awal ofthe plug.
dpment a motor
553.1.7 Where mobile equipment is likely to be used, provision shall be made so that the equipment can be fed fiom an adjacent and conveniently accessible socket-outlet, taking account of the length of flexible cable nonnally fitted to poftable appliances and luminaires.
ared
in
nt duty
monized
Fr. every
oltage or preclude
rions
are
553.2 553-2.1
Cable couplers Except for a SELV or a Class
II
circuit, a cable coupler shall comply where appropriate with
BS 6991 , BS EN 61535, BS EN 60309-2 or BS EN 60320. orlnection of a prolecli\e conductor.
l,
shall be non-reversible and shall have provision for the
553.2.2 A cable coupler shall be ananged so that the connector ofthe coupler is fitted at the end ofthe cable remote from the supply. 554 554.1
GURRENT.USING EQUIPMENT
Electrode water heaters and boilers
554.1.1 Every electrode water heater and electrode boilel shall be connected to an AC.systen.r only, and shall be selected and erected in accordance with the applopriate lequiretnents ofthis section.
211
554,'|,.2 The supplr te the clcctrodc watcr hcatcr or electrodc boiler shall bc controllcd by a linkcd breaker ananged to disconnect the supply from all electrodes simultaneously and provided with an overcurrent protective device in each conductor feeding an elecrode. 554.1.3 The earthing ofthe electrode water heater or electrode boiler shall comply with the requirements of Chapter 54 and, in addition, the shell ofthe electrode water l'reater or electrode boiler shall be bonded to the metallic sheath and armour, if any, ofthe incoming supply cable. The protective conductor shall be connected to the shell of the electrode water heater or electrode boiler and shall comply with Regulation 543.1.1. 554.1.4 Where an electrode water heatel ot electrode boiler is iirectly connected to a supply at a voltage exceeding low voltage, the installation shall include an RCD aranged to disconnect the supply tl'om the electodes on the occurrence of a sustained earth leakage cuffent in excess of 10 % ofthe rated current ofthe electode water heater or electrode boiler under normal conditions of operation. except that if in any instance a lrigher value is essential for stability of operation of the electrode water heater or electrode boiler, the value may be increased to a maximum of 15 %. A tirre delay may be incorporated in the device to prevent ulnecessary operation in the event of imbalance of short duration.
554.1.5 Where an electrode water heater or electrode boiler is connected to a three-phase low voltage supply, the shell ofthe electrode water heater or electrode boiler shall be connected to the neutral olthe supply as well as to the earthing conductor. The current-carrying capacity of the neutral conductor shall be not less than that of the largest line conductor connected to the equipment. 554.1
.6
Except as provided by Regulation 554. t.7. where the supply to an elechode water heater or electrode
boiler is single-phase and one electrode is connected to a neutral conductor earthed by the distributor, the shell of the electrode water heater or elecffode boiler shall be connected to the neutral ofthe supply as well as 10 the earthing conductor
554/1.7
Where the electrode water heater or electrode boiler is not piped to a water supply or in physical
contact with ar.ty earthed metal. and where the electrodes and the water in contact with the electrodes are so shielded in insulating material that they cannot bc touched while the electrodes are live, a fuse in the Iine conductor may be substituted for the circuit-breaker required under Regulation 554.1.2 and the shell of the electrode water heater or electrode boiler need not be connected to the neutral olthe supply.
554.2 554.2.1
Heaters for liquids or other substances having immersed heating elements
554.3 554.3.1
Water heaters having immersed and uninsulated heating elements
Every heater for liquid or other substance shall incorporate or be provided with an aulomatic device to prevent a dangerous se in temperature.
Every single-phase water heatcr or boiler having an uninsulated heating element immersed in the water shall comply rvith the requirernents ofRegulations 554.3.2 and 554.3.3. This type ofwater heater or boiler is deemed not to be an electrode water heater or electrode boiler.
554.3.2 All metal parts ofthe heater or boiler which are in contact with the water (other than cunenlcarying pats) shall be solidly and rnetallically connected to a metal water pipe through which the water supply to the heater or boiler is provided, and that water pipe shall be connected to the main eafihing teminal by means independent of the circuit protective conductor.
554.3.3
The heater or boiler shall be pennanertly connected to the electdcity supply thr-ough a double-pole Iinked switch which is either separate from and r,"ithin easy reach ofthe heater or boilel or is incorporated therein, and the wiring from the heater or boiler shall be connected directly to that switch without the use of a plug and socket-outlet.
554.3.4 Before a heater or boiler ofthe type relered to in Regulation 554.3.1 is connected, the installer shall confinn that no single-pole switch, non-linked circuitbreaker or fuse is fitted in the neufal conductor in any patl of the circuit between the heater or boiler and the origin ofthe irstallation. 554.4
NOTE:
Heating conductors and cables For electric floor and cejling heating systc[rs in buildings the require,nents of Section 753 must also be met.
554.4.1 Where a )reatirrg cablc is required to pass through, or be il close proximity to. tr.raterial which prescnts a fire hazard, the cable shallbe enclosed in material having the ignitability charactedstic 'P'as specified in BS,176-12 and shall be adequately protected from any rnechanical damage reasonably foreseeable during installation and use.
212
554.4.2 Aheating cable intended for laying directly in soil. concrete. cemenl screed or other material used for road and buildirg construction shall be:
(i) ri i;
capable olwithstanding mechanical damage under the conditions that can reasonably be expected to prevail during its installation, and
(ii)
constructed of mate al that conditions of service.
will be resistant to damage from
dampness and/or corosion under normal
554.4.3 A heating cable laid directly in soil, a road or the structure ofa building shall be installed so that it: (i) is co[ipletely embedded in the substance it is intended to heat, and (ii) does not suffer damage in the event ofmovement nomally to be expected in it or the substance in whiclt it
ae CS
is embedded. and
:.7 is
)a
I
..f
(iii) complies in all respects with the manufacturer's instructions and recornmendations. 554.4.4 The load of every floor-warming cable under operation shall be limited to a value such that the tnanufacturer's stated colductor temperature is not exceeded. Other factors can limit the maximurn temperature at rvhich the cable can be run, such as the tempemture rating ofany terminations or accessories, and any material with \\.hich it is in co[tact.
,1).. AS
e
555
TRANSFORMERS
555.1
Autotransformers and step-up transformers
555.1.1
Where an autotansfonner is connected to a circuit having a neutal conductor, the common ten'ninal
-.ithe winding shall be connected to thc neutral conductor. A step-up autotransfonner shall not be connected to an IT system.
555.1.2
r,:lll
555.1.3 Where a step-up transforner is used, a linked switch shall be provided for disconnecting the :ansformer from all live conductors ofthe supply.
-;cel :, he l:
556
L)L
/Vot used
AUXILIARY CIRCUITS
557
Scope
557.1
:'
lce
:.
rhe
-ltis scction applies to auxiliary circuits, except thosc covcred by specific product or systern staldards. c.g. thc ,.'nstruction ofassemblics ofclcctrical equipment to the approp ate pafl olthc BS EN 61439 series. Nof used
557.2
r:ris :., ing :..':ltef .::rt of
5
57.3
Requirements for auxiliary circuits
5
57.3.1
General
Tbe power supply, AC ot'DC, for an auxiliary circuit may be either dependent or independent ofthe main circuit .rccording to its required flrnction. Ifthe status ofthe main circuit has to be signalled, then the signalling circuit shall be able to operate independently ofthat main circuit.
557.3.201 Control circuits :-iio1e -.:ie
ilt.
-: ud .hall
of
A control circuit shalt be designed, aranged and protected to limit dangers resulting lrom a fault between the .ontrol circuit and other conductive pafts liable to cause malfunction (e.g. inadvertent operation) ofthe controlled .quipment.
557.3.2
Power supply for auxiliary circuits dependent on the main circuit
557.3.2.'l
General
-\uxiliaty circuits with a power supply dependent on the main AC circuit ti) directll tsee Figure 55.11. or ir
hiclt in on
(ii) (iii)
via
a
rectilier (see Figure 55.2), or
via
a
transformer (see Figure 55.3).
sha11
be connected to the main circuit:
It is recommended that auxilialy circuits supplying primarily electronic equipment or systems should not be supplied directly but at least via simple separation from the main circuit.
ZIJ
Fig 55.1
-
Auxiliary circuit supplied directly from the main circuit L1
L2 L3 N
Terminals for the auxrlrary ctrcuri
Fig 55.2
-
Auxiliary circuit supplied from the main circuit via a rectifier L1
L2 L3 N
Terminals for the auxiliary circuit
Fig 55.3
-Auxiliary circuit supplied from the main circuit via
a transformer
L1
L2 L3 N
Terminals for the auxiliary circuit
NOTE:
For an auxiliary circuit supplied from the main circuit. either directly or via a rectifier, the auxiliary circuit begins at the connection point to the main circuit, see Figures 55.1 and 55.2. In the case ofa transformer supply, the auxiliary circuit begins on the secondary side ofthe transfomer, see Figure 55.3.
557.3.2.2 Auxiliary circuit supplied from the main circuit via transformer Where an auxiliary circuit is supplied by more than one transformel they shall be connected in pamllel both on the pdmary and secondary sides.
557.3.3
Auxiliary circuit supplied by an independent source
Where an indcpendent source is used a loss of supply or undervoltage ofthe main circuit source shall be detected. An independent auxilialy circuit shall not create a hazardous situation.
NOTE:
214
Batteries and a power supply system independent ofthe mains are examples ofindependent sources.
557.3.4
Auxiliary circuits with or without connection to earth
557.3.4.1
General
An auxiliary circuit shall cornpll \\ith the .'arthing requirements ofBS 7671 except
as modified by Regulation
55'7.3.4.2 or 551.3.4.3.
NOTE 1: lt depends on the requirements tbr an au:iilian circuit as to whether it is operated eathed or unearthed. For example, in an earthed auxiliary circuit an eanh t'ault in a non-earthed conductor leads to disconnection ofthe power supply of the auxiliary circuit; in an unearthed auxilian circuit. an canh fault in a conductor leads only to a signal from the IMD (see Rcgr ation 557.3.4.3). NOTE 2: The use of unearthed auxiliary circlrits should be considered \!here high reliability is required.
557.3.4.2
Earthed auxiliary circuit
An earthed auxiliary circuit supplied via a transfomrer shall be connected to earth only at one point on the secondary side of the tmnsformer. The connection to eafih shall be situated close to the ffansfomer The connection shall be easily accessible atrd capable ofbeing isolated for insulation [leasurement.
557.3.4.3 Unearthedauxiliarycircuit Except in the case of a SELV or PELV circuit, if an auxiliary circuit is operated unearthed via a tmnsformcr, an insulation monitoring device (IMD) according to BS EN 61557-8 shall be installed on the secondary side. Consideration shall be given to the use ofdsk assessment to detennine whether the signal from the IMD is to initiate an acoustic and/or a flash alam, or be transmitted to a monitodng system.
557.3,5
Power supplies for auxiliary circuits
557.3.5.1
General
The mted voltage ofan auxiliary circuit, and the components used in the circuit, shall be compatible with the supply to that circuit.
NOTE 1: If the supply voltage is too low lbr the design of the circuit then the opemtion will not be reliable for the proper fliirction ofrelays.
Account shall be taken of the effects ofvoltage drop on the electrical equipment ofthe auxiliary circuit, including inrush and starting currents. NOTE 2: Motors starting direct-on-1ire can draw a stafiing curent from the rnain circuit that will reduce the supply voltage to an auxiliary cilcuit dependent on the main circuit, below the minimum operating yoltage ofthe associated switchgeaf.
557.3.5.2 Standby power supply or power supply for safety services \\rhere a standby power supply or a power supply from a generating set is used to supply auxiliary circuits. the fiequency variation shall be taken into account.
557.3.5.3
AC supply
The nominal voltage ofcontrol circuits shall preferably not exceed:
(i) (ii)
230 V for circuits with 50 Hz nominal frequency 277 V for circuits with 60 Hz nominal frequency
respectively, taking into account voltage tolerances according to BS EN 60038.
NOTE:
The dimelNio[ing of cable lcngth with rcspect to the conductor capacitances, e.g. connection to a limit switch, necds to be coordilatcd with the selccted relays or solcnoid valves. The standing voltage caused by high conductor capacitances may impair the switching offofrelays or solcnoid valves.
557.3.5.4
supply 557.3"5.4.1 Supply by a power system DC
The nominal voltage of control circuits shall prefembly not exceed 220
V
557.3.5.4.2 Supply by batteries Where batteries are used as a power supply for auxiliary circuits, the voltage fluctuation due to charging or discharging shall not exceed voltage tolerances specified in BS EN 60038, untess the auxiliary circuit is specifically designed to compensate for such voltage fluctuation.
557.3.6
Protectivemeasures
557.3.6.1 Protection
of wiring systems
NOTE 1: In the case ofcxtencled auxiliary circuits it is necessary to check that the requircd operating currenl ol the protective device will bc achier ed also al thc far end ofthe respective cables or conductors' Regulation '1ll' l ' Single-phase eathedAC auxiliary circuits supplied on the secondary side ofthe trauFfonner for an auxiliary supply and earthed DC auxiliary circuits are pennitted to be protected by single-pole devices. The protcctile devices shall only be inserted in conductors whicl] are not connected directly to earth.
In uneafihed AC or DC auxiliary circuits, shof-circuit protection shall be provided for all line conductors. NOTE 2: Thc use ofprotecti!e devjces which disconnect all lines ofan unearthed auxiliary circuit will aid lault dlagnosis and maintenance activities.
If the short-circuit protective device on the primary side ofthe transformer for an auxiliary circuit is selected so that it also protects against short-circuit current on the secondary side, a protective device on the secondary side ofthe tmnsfonner nlay be omitted. NOTE 3: For a fault or the transfonner secondary side. thc magnitude ofthc short-circuit curaent on the pimary side depends also o11 the impedarce ofthe transformer.
557.3.6.2 Protection againstshort-circuit Switching contacts of electrical switching devices ofthe auriliary circuit shall be protected against damage caused by shorl-circuit cunents, according to the manufacturer's instmctions.
Characteristics of cables and conductors Minimum cross-sectional areas
557 .4
557.4.1
order to provide adequatc mecharrical strength. thc lollowing minimum cross-sectional areas indicated in Tahle 55.2 shall be mct. Ifthere are special nrcchanical strength requirencnts for cables or contluctors, then a Iarger ctosssectional area ofconductor, sclccted ilr accordance with Chaptet 52, may be rcquired. I11
TABLE 55.2
-
Minimum cross-sectional area of copper conductors in
mm'?
Type of cable Single-core
Application
Single-wire ControlcircLrits"
Strardcd
0.s
Multicore
Two-core
0.5
Screened
Unscreened
Screenccl oI unscreeneal
0.5
0.5
0.1 0.1
Data transl'cr "
Othcr auxiliary circuits may teed a larget cross_sectional arcA ofcopper condr.tctor,
NOTE;
e.g. for
The cross-sectiotlal area ofcopper conductors is derived from Section 52'1'
557.5
Requirements for auxiliary circuits used for measurement
557.5.1
General
Measuring circuits are auxiliary cilcuits with dedicated requirements which are given in the following subclauses.
557.5.2
Auxiliary circuits for direct measurement of electrical quantities
An auxiliary circuit for direct measurement of elect cal quantities shall be protected against the effects of a fault by one olthe following means: (i) Provision ofa device for protection against fault current in accordance with Section 434. Where operation of the device could cause danger, or lead to a hazardous situation, such operation shall also cause discomection
of the main circuit
(ii)
Siurultaneous fulfilment ofconditions (a) and (b) ofRegulation 434.3.
557.5.3
Auxiliary circuits for measurement of electrical quantities via a transformer
557.5.3.1 Currenttransformer Where a measuement device is connected to the mair circuit via a curent transfomer, the following requirements shall be taken into account: (i) The secondarl, side of thc transfbmrer in a low voltage installation shall not be earthed, except where the measurement can onh be carried out wilh a connection to earth
216
I I
(ii) Protective de\.ices interrupling the circuit shall not be used on the secoudary side ofthe rransibrmer
(iii) Conducton on the secondary side of the transfonner shall be insulated for the highest r oltage ol anl lir e parts or shall be installed such that their insulation cannot come into contact n ith other li\e pafis. e.g.
.1
contact with busbars
(iv)
)l
l1
Teruinals for temporary measurements shall be provided.
The above requirements do not apply to summation cunent tmnsfomers where'hazardous voltages do not occur, e.g. equipment for insulation fault location accordirg to BS EN 61557-9.
I
557.5.3.2 Voltagetransformer I
The secondary side
557.6 557.6"1
l.1t
ods
be protected by a shofl-circuit protective device.
Functional considerations Voltage supply
Where loss olvoltage, i.e. voltage fluctuation, overvoltage or undervoltage, could cause the auxiliary circuit to be unable to perfonn its intended function, means to secure the continued opelation of the auxiliary circuit shall be
provided.
557.6.2 ..ed
ola voltage transformer shall
Quality of signals depending on the cable characteristics
The opemtion ofan auxiliary circuit shall not be adversely affected by the characteristics, including impedance and length, ofthe cable between operational components. The capacitance ofthe cable shall not impair the proper opemtion of an actuator in the auxiliary cilcuit. The cable characteristics and length shall be taken into account for the selection of switchgear and controlgear or electronic
circuits.
NOTE:
For an extensive auxiliary circuit. the use ofa DC power supply or bus-system is recommended.
eble rOSS-
557.6.3
Measures to avoid the loss of functionality
An auxiliary circuit serving a special function where reliability is a concern will require additional
design considerations to lninimize the likelihood of wiring laults. These wiring faults could result in loss offunction and/ or loss of signal. Among the design considerations are:
(i) (ii) (iii)
selection of appropriate installation methods for cables
selection of equipment where a fault from line to exposed-conductive-pafts is not possible, e.g. Class equipment
II
use of installation methods and equipment that are inherently short-circuit and earth fault proof.
For the design of installations and equipment that are inhelently short-circuit and earlh fault proof, the following shall be considered:
(a)
Arangemeflts ofsingle conductors with basic insulation, together with measures to prevent mutual contact and contact with exposed-conductive-parts. This may be achieved by: installation in (insulated) cable nunking systems, or installation in (insulated) conduit
(b)
Arrangements of: siugle-core cables, or
-
-.ru1t bY
single-core, non-metallic-sheathed cables, or rubber-insulated
of ,:lection , :rion
fl
exible cables
(c)
Provision of prctection against mechanical damage and ol safe distance lrom flarnmable material for nonmetallic sheathed cables
(d)
Arrangements ofron-metallic-sheathed cables with nominal voltage Uoru at least 0.6/1 kV (U0 = conductor to Earth voltage, U: conductor to conductor voltage)
(e)
Use ofcables with an insulation which is self-extinguishing ard flame-retardant
(0 Use of cables that are afforded physical protection by being buried, e.g. installation of cables in soil or concrete. --:fcments ..
here tlle
557.6.4 Current-limitingsignaloutputs In eafihed or uneallhed auxiliary circuits with current-limiting signal outputs or electronically controlled protection against short-circuit conditions. respectively, the signal circuit shall be disconnected within 5 s if the respective measure operates. In special cases. a shorter disconnection time may be required. For cunent-li[riting signal outputs or electronically controlled protection olthe signal output, respectively, automatic disconnection of supply may be omitted if a hazardous situatior is not likely to occur.
557.6.5
Connection to the main circuit
557.6.5.1 Auxiliary circuits without direct connection to the
main circuit
Electrical actuators. e.g. actuating relays, contacto$, signalling lights, electromagnetic locking devices, shall be connccted to the common conductor (see Figure 55.4):
(i) (ii)
in earthed auxiliary circuits, at the earthed (common) conductor in unearthed auxiliary circuits, at the comDlon conductor
Fig 55.4
-
Configuration of an auxiliary circuit
Overcu rrent protective
device
Switched conductor
Exception: Switching elements ofprotective relays, e.g. overcurent relays, may be installed between the eafihed or the non-eaithed conductor and a coil, provided that:
(a)
this co[rection is contained inside a comn]on enclosure, or
(b)
it leads to
a simplification olextemal control devices, e.g. conductor bars, cable drums, multiple connectors, and takes into account the requirements ofRegulation 557.3.6.2.
557.6.5.2 Auxiliary circuits with direct connection to the main circuit Ifthe auxiliary circuit
(i)
is:
supplied between two
lire conductors (e.g. Ll and L2 ofan IT system), two-pole switching contacts shall
be used
(ii)
connected to the earthed reutral ofthe main circuit, the requirements ofChapter 43 apply.
557.6.6 Plug-inconnections Interchangeability between multiple plug-in connections is permitted only where damage or introduce a fisk of fir'e, electric shock or injury to pe$ons. NOTE 1: These plug-in connections fonn
a
it will not result in mechanical
palt ofthe auxiliary circuit(s) and nray conduct different signals.
NOTE 2: Plotection against interchangeability may be achieved by marking. polarization, design or electronic interlocking. The connecto$ shall be secured by a means to prevent unintended disconnection.
558 559 559.1
A/ot used
LUMINAIRES AND LIGHTING INSTALLATIONS
Scope
This section applics to the selection and erection of luminaires and lighting installations intended to be pafi of the fixed installation.
218
I j:F-.:.:- -N-:llLrns. NOTE ,l: For outdoor lightilg insrallarions. exrra-lo\\ \ oltage lighting installalions and lighting inslalleiiLrn. i:r refer to Pat 7. The requiements
ofthis section do not apply to:
(i) (ii)
high voltage signs supplied at low voltage (such as neon tubes) signs and luminous discharge nrbe installations operating from a no-load rat;d output voltage exceeding 1 kV but not exceeding l0 kV (BS EN 50107)
(iii)
temporary festoon lighting.
NOTE 2: The rcquirenlerts tbr high voltage signs are given in BS 559 and the BS EN 50107 serics'
559.2
Not used
559.3 NOTE:
General requirements for installations
See Table 55.3 for
ar explanatioll ofthe symbols used in luminailes, in controlgear for lLuninaires and in tle installation
ollu!ninaires.
Every luminaire shall comply with the relevant standard for manufacture and test of that luminaire and shall be selected and erected to take account ofthe manufacturer's instructions' 559.3.1
For the pulposes of this section, luminaires without transfomels or convello$ but which
559.3.2
are
iitted with extfa-low voltage lamps connected in series to a low voltage suppty shall be consideled as low voltage iquipment not exha-low voltage equipment. These luminaires shall be either class I oI class II equipment. Where a luminaire is installed in a pelmet, there shall be no adverse effects due to the presence or operation ofcurtains or blinds.
559.3.3
559.3.4
Atrack system for luminaires shall comply with the requirements ofBS EN 60570'
559.4 559.4.1
Protection of the surroundings against thermal effect3 General
In rhe selection and erection ofa luminaire the therrnal effects ofradiant and convected energy on the suroundings .hall be taken inlo account, including:
(i) iii)
the maximum permissible power dissipated by the lanps the fire-resistance of adjacent material at the point ofinstallation, and
in tle thermallv affected areas
tiii) (iv)
the rniniurun distance to combustible materials, including material in the path of a spotlight beam the relevant markings on the luminaire.
559.5
Wiring systems
559.5.1
Connection to the fixed wiring
.1l each fixed lighting point one ofthe following shall be used for the tennination ofthe wiring system:
(i) 1ii)
A ceiling rose complying with BS 67 A lunrinaile supporting coupler (LSC) complying with BS 6972 or BS 7001
iii) A batten lampholder or a pendant set complying with BS EN 60598 ir ) A luminaire complying with BS EN 60598 r\ ) A sujtable socket-outlet complying with BS 1363-2, BS 546 or BS EN 60309-2 rr i) A plug-in tighting distdbution unit complying with BS 5733 \ ii) A connection unit complying with BS 1363-4 lii) Appropriate temrinals eucloscd in a box complying with the relevant part ofBS EN 60670 series or-BS 4662 ,ir) A device for counecting a luminaire (DCL) outlet complying with BS IEC 61995-1 r\) An installation coupler couplying with BS EN 61535. {oTE: In suspe[ded ceilings one plug-ir lighiing distribution unit rnay be used for a number ofluminaires. r
r
-,
559.5.1.201 A ceiling rose or lampholder shall not be installed in any circuit opemting at a voltage normally ..;;eeding 250 volts.
559.5.1.202 Aceilin-srose shall rlotbeused for the attachrnent ofmore than one outgoing flexible cable unless it is specially designed for multiple pendants.
559.5.1.203 Luminaire supporting couplers and devices for the connection ofluminaires are designed specilically for the elect cal connection of lulr]inaires and shall not be used for the connection of any other equipment. 559.5.1.204 Lighting circuits incolporating Bl5,822, E14, E27 or E40 lampholders shall be protected by
an
overcurrent protective der.ice olrlaximum rating l6 A.
559.5.1.205 Bayonet lampholders 815 and 822 shall comply withBs EN 61184 and shall have the temperature rating T2 desffibed in that standard. 559.5.1.206 In circuits ofa TN or TT system, except for E l4 and 827 lampholders complying with BS EN 60238, the outer contact of every Edison screw or single centre bayonet cap type lampholder shall be comected to the neutral conductor This regulation also applies to track mounted systems. 559.5"1.207 A lighting installation shall
NOTE:
See Table 537.4
be appropriately controlled.
fol guidance on the selection ofsuitable prctective, isolation and switching devices.
559.5.1.208 Considemtion shall be given to the provision of the neutral conductor, at each switch position, to facilitate the installation of elechonic switching devices.
559.5.2
Fixing of luminaires
Adequate means to flx luminaires shall be provided.
The fixing means may be mecharical accessories (e.g. hooks or screws), boxes or enclosures which are able to support luminaires or supporling devices for connecting a luminairc. Irt places u,here the fixing means is intended to supporl a luminaire, the fixing means shall be capable of carrying a nass ofnot less than 5 kg. Ifthe mass ofthe lurninaire is greater than 5 kg, a fixing means capable ofsupporting the mass ofthe luminaire shall be installed. The installation ofthe fixing neans shall be in accordance with the manufacturer's instructions.
The weight of luminaires and their eventual accesso es, e.g. shades, shall be compatible with the mechanical capability ofthe ceiling or suspended ceiling or suppoting structure where installed. Any flexible cable between the fixing means and the luminaire shall be installed so that any expected stresses in the conductors, terminals and teminations will not impair the safety of the installation. (See also Table 4F3A of Appendir( 4.)
559,5.3 559.5.3.1
Through wiring The installation of through wiring in a luminaire is only pemitted
if the luminaire is designed for
such wiring.
559.5.3.2 A cable for through wiring shall be selected in accordance with the temperature infonnation on the luminaire or on the manufacturer's instruction sheet, ifany, as follows:
(i)
For a luminaire complying with BS EN 60598 but with temperature marking, cables suitable for the marked temperature shall be used
(ii)
Unless specified in the manufacturer's inshxctions, for a luminaire complying with BS EN 60598 but with no tempemture marking. heat-resistant cables are not required
(iii)
In the absence of information, heat-resistant cables and/or insulated conductors of type H05S-U, H05S-K, H05SJ-K, H05SS-K (BS EN 50525 series) or equivalent shall be used.
559-5.4
Devices for connection of luminaires to the supply
Ifthe lurninaire
(i) (ii) (iii) (iv) (v) (vi)
220
does not provide a connecting device for connection to the supply, the connecting device shall be:
terminals according to BS EN 60998, or a device
for connecting a lurninaire (DCL) plug accordirg to BS EN 61995, or
an installation coupler according to BS EN 61535, or
supporting coupler (LSC) plug accolding to BS 6972 or BS 7001, or a
male comector (plug) of a plug-in lighting distribution unit accolding to BS 5713, or
another suitable a:rd appropriate connecting device.
NOTE:
For the installation of supply cables. see also Regulation 522.2.201.
559.5.5
Groups of luminaires
Groups of luminaires divided between the line conductors of a polyphase ci.cuit u,ith only otle common neutral conductor shall be provided with at least one device disconnecting simultaneousl)- all line conductors.
NOTE:
See also Section 537.
559.5.6
Protection against heat and UV radiation effects within luminaires
Extemal cables and cores ofcables comrected within a lurninaire or passing through shall be so selected and erected that they will not suffer damage or deterioration due to heat and IJV radiation generated by the lurninaire or its lamps (e.g. shielding ofthe cable fi'om heat andior UV by means of hearuv-resistant sleeving).
lndependent lamp controlgear, e.g. ballasts
559.6
Only independent lamp controlgear marked as suitable for independent use, according to the relevant standard, shall be used extemal to a luninaire. Only the following are pemitted to be mounted on a flammable surface:
(i) (ii)
A 'class P' thermally protected ballast/transformer A tempemture declared thermally protected ballast/transformer
NOTE:
For an explanation ofsymbols used see Table 55.3.
Compensation capacitors
559.7
Ito
Cornpensation capacitors having a total capacitance exceeding 0.5 pF shall only be used in conjunction with discharge resistors. Capacitols and their marking shall be in accordance with BS EN 61048.
nga r tlle
This requirement does not apply to capacitors foming paft ofthe equipment.
559.8
Protection against electric shock for display stands for luminaires
Protection against electric shock lor circuits supplying display stands for luminaires shall be provided by either: rIical
..'. in
l\trl
(i) (ii)
a SELV or PELV supply, or
a residual current deyice having a rated residual operating curent not exceeding 30 mA which provides both automatic disconnection of supply according to Section 411 and additional protection according to Regulatiolr 415.1.
559.9 ..r
l'ot
:r
ille
::.:'k.-,'l ri ith
bcl
Stroboscopic effect
In the case of lighting for premises where machines with moving pafis are in operation, consideration shall be given to sfoboscopic effects which can give a misleading impression ofmoving parts being stationary. Such effects may be avoided by selecting lLuninaires with suitable lamp controlgear, such as high frequency controlgear, or by distributing lighting loads across all the phases ofa polyphase supply.
559.10
Ground-recessedluminaires
For grould-recessed luminaires, the selection and erection shall take account ofthe guidance given in Table A.1 BS EN 60598-2- 13.
of
TABLE 55.3
- Explanation of symbols used in luminaires, in controlgear for luminaires and in the installation of luminaires
BS EN 60s98-l:2008 Recessed lurninaire not suitabie for direct mouflting on normally flarrmable surfaces
Surface mounted luminaire not suiiable for direct mounting on normally flammable surfaces
Luminaire not suitable for covering with thermally jnsulating material
a
/---...?,4 (t'c(<'
is optional)
Luminaire for use with high plessure sodium lamps that require an extemal ignitor
(BS EN 60598 series)
(BS EN 60598 series)
Luminaire designed for use with bowl
Luminaire lor use with high pressure sodium Iamps having an intemal stalting device
Use ofheat resistant supply cables, interconDecting cables, or extemal
widng (number of conductors ofcable
mirror lamps (BS EN 60598 series)
(BS EN 60598 series) l{ated nraximum anlbient temperature
ta....
oC
(BS LN 60598 se es)
Luminairc \!ith limitcd surface tcmpemturc
(BS EN 60s9lt-2-24)
Waming against the use of cool-beam lan'rps
OL AM
(BS EN 60598
ser
ies)
Short-circuit proof (inherently or non-inherently) safety isolating transformer (BS EN 61558-2-6)
c---,
i
Minirnum distance Aom lighted objects
Temperature declared
(mctres)
thermally protected lamp controlgear (... replaced by temperatue)
(BS EN 60598 series)
(BS EN 61347- 1) Rough serr'ice luminaire
(BS EN 60598 series)
W-ru
Replace any cracked plotective screen
(BS EN 60598 series)
Electoric convefior for an extra-low voltage
lighting installation
Themally protected lamp contolgear (class P) (BS EN 61347-r)
Lrrrrrira:re desicned lor use with sel{ .lriclded rung:ren halotsen lamp. or sell shiclded metal halidc lamps only
Independent ballast
BS EN 60417 sheet No. 513 8
(BS EN 60598 series)
222
GHAPTER 56 SAFETY SERVICES CONTENTS 560.1
SCOPE
560.4
CLASSIFICATION
560.5
GENERAL
560.6
ELECTRICAL SOURCES FOR SAFETY SERVICES Special requirements for safety services having sources not capable of operation in parallel
560.6.8 560.6.9 560.6.10 560.6.11
560.6.12
Special requirements for safety services having sources capable of operation in parallel Central power supply sources Low power supply sources
560.6.1 3
Uninterruptible power supply sources (UPS) Generator sets for safety services
560.6.14
Monitoring of safety sources
560.7
CIRCUITS OF SAFETY SERVICES
560.8
WIRING SYSTEMS
s60.9
EMERGENCY LIGHTING SYSTEMS
s60.10
FIRE DETECTION AND FIRE ALARM SYSTEMS
560.11
LIFE SAFETY AND FIREFIGHTING APPLICATIONS
CHAPTER 56 SAFETY SERVICES :6 0.1
SCOPE
:. chaptcr covers gereral requirements for safety services, selection and erection ofelect cal supply systenrs for
-:::r
sen,ices and electrical safety soulces. Standby electrical supply systems are outside the scope.
r: .haptel does l]ot apply to installations in hazardous areas (BE3), for which requirements are given in BS EN
. -9_ l.l. \tTE: Examples ofsafety scryices include (this list is not exhaustive): - Errergency lighting - Fire purnps Fire rescue service litts Fire detection and alann systems CO detection and alann systcms Fire evacuation systems Srnoke ventilation systems Fire services communication systelns Essential medical systems
Industrial safety systcms.
:.:.:2
/Vot used
i:-'3
Not used
,-
560.4
CLASSIFICATION
560.4.1 An electrical safety service supply is either: (i) a non-autornatic supply. thc stafting ofwhich is initiated by an operatol or (ii) an automatic supply. the starting of which is independent ofan operator An automatic supply is classified
(a)
as
follows, according to the maximum changeover time:
No-break: ar automatic supply which produces a continuous supply within specifled conditions during the period oftransition, for example as regards variations in voltage and frequency
(b) Very short break: ar automatic supply available within 0.15 s (c) Short break: an automatic supply available within 0.5 s (d) Normal break: an automatic supply available within 5 s (e) Medium break: an aLrtomatic supply available within l5 s (f) Long break: an automatic supply available in lrore than l5 s.
560.4.2 The esseltial equipment for safety services shall be compatible with the changeover time in order to maintain the specified operation.
560.5
GENERAL
560.5.1
Safety services u.ny be reqr"rired to operate at all relevant times including during mains and local supply failure and through fire conditions. To meet this rcquirement specilic sources, equipment, circuits and wiring are necessary Some applications also have particular requirements, as in Regulations 560.5.2 and 560.5.3.
560.5.2
For safety services required to operate in fire conditions, the following two conditions shall be
fulfi11ed:
(i) (ii)
An etectrical source for safety supply shall be so selected
as
to maintain a supply ofadequate dluation, and
all equipment ofsafety services shall be so provided, either by construction or by erection, with fire-resisting proteclion ol adeqttate duration.
NOTE:
The safety source is gencrally additional to the noflnal source. The normal source is, for example, the public supply network.
560,5.3 Where automatic disconnection of supply is used as a protective measure against electdc shock, non-disconnection on the first lault is preferred. ln lT systems, continuous insulation monitoring devices shall be provided which give an audible and visual indication in the event ofa fint fault. 560.5.4
A failure in the control or bus system of of safety serices. 560.6
a
normal installation shall not adversely affect the function
ELECTRICAL SOURCES FOR SAFETY SERVICES
560.6.1 The following electrical sources for safety seruices are recognized: (i) Stomge battedes (ii) Primary cells (iii) Generator sets independent ofthe normal supply (iv) A separate feeder of the supply network that is effectively independent of the notmal feeder ' 560.6.2
Safety sources for safety sen,ices shall be installed as fixed equipment and in such cannot be adversely affected by failure ofthe normal source.
a
nlanner that they
560.6.3
Safety sources shall be installed in a suitable location and be accessible only to skilled or instructed pelsons (BA5 or BA4).
560.6,4
The location ofthe safety source shall be properly and adequately ventilated so that exhaust gases. smoke or fumes from the safety sout'ce cannot penetrate areas occupied by one or more pemons.
560.6.5
Separated independent feeders from a dist butor's network shall not serve as electrical sources for safety services unless assurance can be obtained that the two supplies are unlikely to fail concurrently.
560.6.6 560.6.7
The safety source shall have sulicient capability to supply its related safety service.
A safety source [ray, in addition, be used for purposes other than safety services, provided that the availability for safety services is not thereby iurpaired. A fault occurring in a circuit for pruposes other than safet) services shall not cause the iflten'uption olany circuit for saf'ety sen'ices.
224
-.I Special requirements for safety services having sources not capable of operation in parallel
560.6.8
560.6.8.1 NOTE:
Adequate precautions shall be taken to avoid the paralleling of sources.
This may be achieved by mechanical inter'locking.
560"6.8.2 E
Shoft-circuit protection and fault protection shall be pror ided for each source.
Special requirements for safety services having sources capable of operation in parallel
560.6.9
Shofi-circuit protection and fault protectior shall be effective inespective of uhether the installation is supplied separately by either olthe two sources or by both in parallel. NOTE
1
ofa pri\'alc source with the public supply network is subject to authorization by the distribution nctwork opelator (DNO). This oray lequire special devices, for example to prevent reverse power. Refer also to Section 551. rhe DCode (Distributioo Code oflicensed distribution operators) and ENA Engjneering Recomtrendations G83/2
: The Damllcl operatio[
and G59/3.
limit curent circulation in the connection between the neutral points ofthe sources, ol I11plen lrarnronrcs.
Precautions may be necessary to rn panlcul.rr thc cfl'cct
560.6.10
Gentral power supply sources
Batteries shall be of vented or valve-regu)ated maintenance-free t)pe and shall be of hear,y duty indr.rstrial design. for example cells complying with BS EN 60623 or the approp atepafiof the BS EN 60896 serics.
NOTE:
The
560.6.1'l .:xd
es at 20
oC
should be
NOTE:
Low power supply sources
The minirrum design life
ofthe batteries at 20
oC
should be 5 years.
560.6.12 Uninterruptible power supply sources -,; k.
.
l0 yeals.
The porver output ofa low power supply system is lirnited to 500 W for'3-hour duration and 1500 W for a 1-hour duration. Batteries shall be ofheavy duty industrial design, for example cells complying with tsS EN 60623 or the appropriate pafl ofthe BS EN 60896 series are suitable.
:.lllg
t
rnininurr design life ofthe batte
(UPS)
Where an uninterruptiblc power supply is used, it shall:
Lr.
(i) (ii) (jii) (iv)
be able to operate distribution circuit protective devices. and be able to start the safety devices when it is operating in the emergency condition from the invcfter supplied by the battery, and
comply with the rcquircments oiRegulation 560.6. t0, and cornply with BS EN 62040-1 and BS EN 62040-3, as applicable.
560.6.13
Generator sets for safety services
Where a genemting set is used as a safety source, it shall comply with BS 7698-12.
560.6.14 Monitoring of safety sources r.,: lre\
The condition ofthe source for safety services (ready for operation, under fault conditions, feeding from the source for saf'ety services) shall be monitored.
CIRCUITS OF SAFETY SERVICES
560.7 -:a.aiec-
gases-
560.7.1 Except where the recomnendations of other safety standards apply. circuits of safety seryices shall be indeperdent of other circuits.
NOTE:
This rneans that any electrical l'ault or any inteNention or modification in one systelr must Dot affect the correct functioning olthe other This may neccssitate separatiol by fire lesistant materials or different ]outes or enclosures.
560.7.2
Cilcuits of safety services shall rot pass through locations exposed to fire dsk (BE2) unless they are iire-resista[t. The circuits shall not, in any case, pass through zones exposed to explosion risk (BE3).
NOTE: -
_
: r.rl
:
d'.
:.1lal\
Whele placticablc. the passage ofcircuits through locations presenting a fire risk should be avoidcd-
560.7.3
In accordance with Regulation 433.3.3, protection against ovelload tnay be omitted where the loss ofsupply may cause a greater hazard. Where protection against overload is omitted. the occulrence ofan overload :hall be rnonitoled.
225
560,7,4
Overcurrent prorective devices shall be selected and erected so as to avoid an overcurrent in one circuit impai ng the correct operation ofcircuits of safety services.
560.7.5
Switchgear and controlgear shall be clearly identified and grouped in locations accessible only to skilled or instructed persons (B-\5 or BA4).
560.7.6 In equipmenr supplied by two different circuits, a fault occuring in one circuit shall not impair the protection against elec!ic shock or the conect operation olthe other circuit. Such equipment shall be connected to the protective conducto$ ofboth circuits, ifnecessary 560.7.7
Safety circuir cables, other than metallic screened, fire-resistant cables, shall be adequately and reliably separated by distance or by barriers from other circuit cables, including other safety circuit cables.
NOTE:
For battery cables. special lequirements may apply.
560,7.8
Circuits for safety services, with the exception ofwiring for fire and rescue selice lift supply cables and wiring for Iifts with special requirements, shall not be installed in lift wells or other fluelike openings. resistant cables rvill suwive most fires, if they are located in an unstopped vertical well the upward air draught in a fire can generate cxcessive tempemtures above the capabilities ofthe cable so they should be avoided as a route for safety systems.
NOTE: while fre
560.7.9
In addition to a general schematic diagram, full details ofall electrical safety sources shall be given. The inlbmation shall be maintair.red adjacent to the distribution board. A single-line diagram is sufficient.
560.7.10 A drawing or drawings
of the electrical salety installations shall be available showing the exact
location of:
(i) (ii) (iii)
all electrical equipment and distribution boards, with equipment designations safety equiprnent with final circuit designation and particulars and pur?ose ofthe equipment
special switching and monitoring equipment for the safety power supply (e.g. area switches, visual or acoustic
w
atr ing equipment).
560.7.11
A list ofall the cunent-using equipment permanently connected to the safety power supply, indicating the nominal electrical power, rated nominal voltage, curent and starting cuffent, together with its duration, shall be available.
NOTE:
This information lnay be included in the circuit diagrams.
560.7.12
Operating instructions for safety equipment and electrical safety services shall be available. They
shall take into accor.mt all the particulars ofthe installation.
560.8
WIRING SYSTEMS
560.8.1 One or more olthe following wiring systems shall be utilised for safety services required to operate in fire conditions: (i) Mineral insulated cable systems complying with BS EN 60702-1 andBS EN 60702-2andBSEN 60332-1-2
(ii) (iii) (iv)
Fire-resistant cables complying with IEC 60331- l, IEC 60331-2 or IEC 60331-3 and with BS EN 60332-l-2
Fire-resistant cables complying with test requirements ofBS EN 50200, BS 8434 or BS 8491, appropriate for the cable size and with BS EN 60332-1-2 A wiring system maintaining the necessary fire and mechanical protection.
The wiring system selected shall tneet the requirements ofthe relevant code ofpractice appropdate to the application aud shall be mounted and installed in such a way that the circuit integdty will not be impaired during a flre.
NOTE
1:
BS 5266, BS 5839 and BS 8519 specify cables to BS EN 60702-1, BS 7629-1 and BS 7846 as being suitable
when appropridrel) sclccted tol the rpplication. a systern maintaining the necessary fire and mechanical protection could be: constructional enclosures to maintainflte and mechanical protection. or wirirg systems in sepamte fire compatments.
NOTE 2: Examples of
(i) (ii)
560.8.2
Wiring lor cortrol and bus systems of safety services shall be in acaordance with the
same
requirements as the wiring which is to be used for the safety services. This does not apply to circuits that do not adversely aflect the operation ofthe safety equipment.
560.8.3 560.8.4
Reserved .for./itture use
Circuits for safety services which can be supplied by direct current shall be provided with two-pole protection mechanistls. overcurent
226
560.8.5
Srvitchgear and controlgeax used for both AC and DC supply- sources shall be suitable for both AC
and DC operation.
560.9
EMERGENGY LIGHTING SYSTEMS
Emergency lighting systems shall comply with the relevant pafis ofBS 5266 series and BS EN 1838.
560.10
FIRE DETECTION AND FIRE ALARM SYSTEMS
Fire detection and fire alam systems shall comply with the relevant parts ofBS 5839 series.
560.11
LIFE SAFETY AND FIREFIGHTING APPLICATIONS
The selection and installation ol power and control cable systems which are required to maintain their circuit integrity for life safety and firefighting applications shall comply with the relevant parts of BS 8519.
-l-l -l-2
j
-
:.!
PART 6 INSPECTION AND TESTING CONTENTS CHAPTER 61 CHAPTER 62 CHAPTER 63 CHAPTER 64
NOT USED NOT USED
I
NOT USED
I
INITIAL VERIFICATION
I
641
GENERAL
I
642
INSPECTION
I
643
TESTING
I
643.1
General
I
643.2
Continuity of conductors lnsulation resistance Protection by SELV, PELV or by electrical separation
643.3 643.4
Protection by SELV Protection by PELV
643.4.1
643.4.2
I I
I
1
I
643.5
Protection by electrical separation lnsulation resistance/impedance of floors and walls
643.6
Polarity
I
643.7
Prolection by automatic disconnection of the supply
I
643.7.1
General
I
643.7.2 tl4J. / .J
Earth electrode resistance Earth fault loop impedance Additional protection
643.4.3
643.8
Check of phase sequence
643.9 643.10 643.11
Functional testing Verification of voltage droP
644
CERTIFICATION FOR INITIAL VERIFICATION
CHAPTER
651 652 653
228
I
65
PERIODIC INSPECTION AND TESTING
GENERAL FREQUENCY OF PERIODIC INSPECTION AND TESTING REPORTING FOR PERIODIC INSPECTION AND TESTING
I
I
I
I
I I
I
I
I
CHAPTER 61 NOT USED CHAPTER 62 NOT USED CHAPTER 63 NOT USED
fFI*rc'\ *** ; r*
_^
CHAPTER 64 INITIAL VERIFICATION 641 641.'l
GENERAL Every installation shall, du ng erection and on completion before being put into service, be
inspected and tested to verify, so far as is reasonably practicable, that the requirements of the Regulations have been met. 641 .2 The result ofthe assessment ofthe fundameotal principles. Section l3l, the genelal characteristics lequired by Sections 311 to 313, together with the information required by Regulation 514.9.1, shall be made available to the person or persons can)ing out the inspection and testing.
The veriflcation shall ilclude comparison of the results with relevant criteria to conflrm that the
641.3
requirements ofthe Regulations have been met.
641.4 Precautions shall be taken to avoid danger to persons and livestock, and to avoid damage to property and installed equipment, du ng inspection and testing. For an addition or alteration to an existing ilstallation, it shall be ve fied that the addition or alteration complies with the Regulations and does not impair the safety ofthe existing installation. 641.5 641.6
The verification shall be made by one or more skilled persons competent in such work.
641.7
On completion ofthe verification, according to Regulations 641.1 to 611.6, a certificate shall be
prepared.
642
INSPECTION
Inspection sha11 prcccdc tcsting and shall normally bc donc u,ith that part of the irstallatjon undcr 642.1 inspection disconnected liorr.r the supply. The inspection shall be made to verify that the installed electrical equipment is:
642.2
(i)
in compliance with the requirements of Section
5I
I
(this may be ascertained by n.urk or by certiflcation
furnished by the installer or the manufacturer), and
(ii)
correctly selected and erected in accordance with the Regulations, taking into account manufacturcrs' instructions. and
(iii) not visibly damaged or defective so as to impair safety. The inspection shall include at least the checking ofthe following items where relevant: 642.3 (i) Connectionofcorductors (ii) Identiflcationofconductors (iii) Routing of cables in prescribed zones, or protection against mechanical damage, in compliance
with
Section 522
(iv) (v) (vi) (vii) (viii)
Selection ofconductors for current-carrying capacity and voltage drop, in accordance with the design
Connection of single-pole devices for protection or switching in line conductors only Correct connection ofaccesso es and equipment Presence
offire barriers, suitable
seals and protection against thermal effects
Methods ofprotection against electric shock
(a) both basic protection and fault protection, i.e.:
-
SEI V
PELV Double insulation Reinforced insulation
(b) basic protcctior (including measurement of distances, where appropriate), i.e.:
-
protection by insulation of live parts protection by a balTier or an enclosure
-
protection by obstacles protection by placing out ofreach
(c) fault protection:
(i) (il) (iii) (iv)
presence ofadequate arangements for altemative sources(s), where applicable
choice and setting ofprotective and monitoring devices automatic disconnection ofsupply (including FELV) selection and installation ofeafthing arrangements, protective conductors and their connections confirmed for presence and sized in accordance with the design:
r r r r r r (v)
eafihing conductor circuit protective conductors protective bonding conductors supplementary bonding conductors earthing affangements for combined protectiye and functional purposes
exposed-conductive-pafis are connected to the earthing arangement
non-conducting location (including measurement ofdistances, where appropriate) absence of protective conductors
(vi)
eafth-free local equipotential bonding presence of eaflh-free protective bonding conductors
(vii) :.'r
Lrl'I
i::'
,,1r1'1
electrical separation
(d) additional protection
(ix) Prevention of mutual detrimental influence (x) Presence of appropriate devices for isolation and switching correctly located (xi) Presence of undervoltage protective devices (xii) Labelling ofprotective devices, switches and terminals (xiii) Selection of equipment and protective measures appropriate to extemal influences (xiv) (xv) (xvi) (xvii)
Adequacy of access to switchgear and equipment
(xviii)
Erection methods
(xix) (xx)
Presence of danger notices and other waming signs Presence ofdiagrams, instructiors and similar information
Selection and erection of wiring s;stems Selection and installation ofsuitable SPDs where required Measures againstelectromagnetic disturbances.
The inspection shall include a1l parlicular requirements for special installations or locations (Part 7).
643
TESTING
General
643.1
The tests of Regulations 643.2 to 643.1l, where relevant, shall be carried out and the results compared with relevant
crite
a.
Veasuring instruments and monitoring equipment and methods shall be chosen in accordance with the relevart If other measuring equipment is used, it shall provide no lesser degree of performance and
parts of BS EN 61557. safety.
When undefiaking testing in a potentially explosive atmosphere, appropdate safety precautions in accordance with BS EN 60079-17 are necessary The tests of Regulations 643.2 to 643.6, where relevant, shall be carried out in that order before the installation is energized. Where the installation incorporates an eaflh electrode, the test of Regulation 643.7.2 shall also be caried out before the installation is enersized.
231
If
any test indicates a failure to comply, that test and any preceding test, the results of which may have been influenced by the fault indicated, shall be repeated after the fault has been rectifie
643.2
Continuity of conductors
643.2,1 (i) (ii)
The continuity ofconductors arld connectiorls to exposed-conductive-pats and extraneouscondlLctive-parts, ifany, shall be verilied by a measurenent ofresistance on:
protective conductors, including protective bonding corductors, and
in the case ofring final circuits, Iive conductors.
643.3
lnsulation resistance
643.3.1
The insulation resistance shall be measured between live conductors and between live conductors
and the protective conductor connected to the eafihing arangement. Where appropriate during this measurement, line and neutral conductors may be connected together
643.3.2
The insulation resistance measured with the test voltages irdicated in Table 64 shall be considered the main switchboard and each distribution circuit tested separately, with all its fll1al circuits connected but with curent-using equipment disconnected, has an insulation resistance not less than the appropriate value given in Table 64.
satisfactory
if
NOTE I : More specific requirements are applicable for the wiing of fire detection and flre alarm systems in buildings,
see
BS 5839-1.
TABLE 64 Minimum values of insulation resistance Circuit nominal voltage
Minimur insulation
Test voltage DC
resistance
(v)
(Mo)
SELV and PELV
2s0
0.5
Up to and including 500 V with thc cxception
500
1.0
of thc above svstems Above 500 V
r
000
1.0
Table 64 shall be applied when verifting insulation resistance between non-eafihed protective conductors and Earth.
FELV circuits shall be tested at the same test voltage as that applied to the all Lhe test requiremenrs lor lou rolrage circuirs.
p
mary side ofthe source and shall meet
Where surge protective devices (SPDs) or other equipment are likely to influence the verification test, or be damaged, such equipment shall be disconnected before canying out the insulation resistance test.Where it is not reasonably practicable to disconnect such equipment (e.g. fixed socket-outlet incorporating an SPD), the test voltage lor the pafiicular circuit may be reduced to 250 V DC, but the insulation resistance shall have a value of at least I MQ. Insulation resistance values are usually much higher than those ofTable 64. When measured values show evident differences between circuits, further investigation to identify the reasons is required. NOTE 2: Itr locations exposcd to fire hazard, a measulement ofthe insulation resistance between the live conductors should be applied. In practice, it may be necessary to cany out this measurement du ng erection ofthe installation and before connection of the equipment.
643.3.3
Where the circuit includes electronic devices which are likely to influence the results or be damaged, only a measurement between the live conductors connected together and the eafthing arangemelt shall be made.
NOTE; 643.4
Additional precautions, such as disconnection. may be necessary to avoid damage to elecfto1]ic dcviccs.
Protection by SELV, PELV or by electrical separation
It shall be ve fiedthatthe separation ofcircuits isin accordance with Regulation 643.4.1 in the case ofprotecrion by SELV, Regulation 643.4.2 in the case ofprotection by PELV and Regulation 643.4.3 in the case ofprotection by
elect cal separation. The resistance values obtained in
the tests ofRegulations 643.4.1lo 643.4.3 shall be at least
that ofthe circuit with the highest voltage present in accordance with Table 64.
643.4.1
Protection by SELV
The sepalation of the live pafts liorn those ol other circuits and tiom Lanh. accirding to Section 414, shall be conlimed by a measurement of the insulation resistance. Thc rcsistance r alues rrbtained shail be in accordance
* ith Table
64.
643.4.2
Protection by PELV
The separation ofthe live pafts from other circuits, according to Section 414. shall be confinned by a measurelrent ofthe insr.rlation resistance. The resistance values obtained shall be in accordance rith Table 64.
643.4.3
Protection by electrical separation
The sepamtion of the live parts from those of other circuits and from Eath, according to Section 413. shall be confimed by a nleasurement of the insr.rlation resistance. The resistance vah"res obtained shall be in accordance rr ith Table 64. In the case of electrical separation with more than one item of cun'ent-usil'rg equipment, either br measurcment or by calculation, it shall be ve lled that in case ol two coincidental faults with negligible impedance between different line conductors and either the protective bonding conductor or exposed-conductivelafts connected to it, at least one of the faulty circuits shall be disconnected. The disconnection time shall be in l!-cordance with that 1br the protective measure autontatic disconnection of supply in a TN systen.r.
lnsulation resistance/impedance of floors and walls
643.5
Where il is necessary to cornply with the requiremelts of Regulation 418.1, at least three :ri-asufen]ents shall be made in the sarle location" one ofthese measurements being approximately I nr tronl ::r\ acccssiblc cxffancous-corlductivc-part in the location. The other two measurements shall be nade at greater :.'tances. The measulement of resistancei ir]rpedarrce of insulating floors and walls is carried out u,ith the systern -,ltagc to Eafth at nonrinal t'r'ecluclcy. The above series of rneasuLements shall be repeated 1br each relevant ...rf'acc of the location. 643.5.1
\OTE:
Iru her i lbnralion on measLn-curerlt ofthc insulurtion rcsistancc,'irnpcdancc offloors and rvalls can bc fouud in App!'ndix li.
643.5,201 A[y
insulation or ius.rlaling arangclncnt of cxtrancous-concluctivc-pa]-ts intcndcd to satisfy (iii) shall: when testcd at 500 V DC bc not lcss than I MO. and
: :gulation
i) ri)
1
rri)
418. I .4
be able to rvithstand a test voltage of at least 2 kV AC rms^ and
rot
pass a le-akage currcnt cxcc!'ding
lrnAinnomal
conclitions of use.
Polarity
443.6
: j!'re lelevant, tire poladty ofthe supply at the origin ofthe installation shall be velified before the installation is :-
rrlrized. Where singlc-pole switching deviccs are not pemritted in the neutral coDdrrctor. a test shall be made to
i:ri'\ that all such devices ale connected in the line conductor(s) only. -
-: ing the polarity test. it shal1 be verilicd drat: i) ri)
:rt
every f'use and single-pole control and protective device is corulected in the line conductor only. and except fbr El4 and E27 lanpholders to BS EN 60238, in circuits having an eafthed neutml conductol'. celtre contact bayonet and Edison screw lampholders have the outer or screwed contacts connected to the neutral conductor- and
rviring has been conectly conr]ected throughout the installation.
4"13,7
Protection by automatic disconnection of the supply
-'rc RCDs are applied also for protcction against fire, the ve fication of the conditions fbr protection by
-:
iDatic disconnection ofthe supply may be considered as satisfying the relevant requirements ofChapter 42.
:13,7.1 General - . rcrification olthe etlectiveness .-:rii!-d
:
as
ofthe
measures for thult protection by autornatic disconnection
follows:
TN system
:::iiance with RegrLlation .111.4 shall be veri6ed by: r]easurer]]ent oflhe earth t'ault loop impedance (see Regulation 6;13.7.i
._^*---
)
ofsupply
is
(2)
vedfication
of the characteristics and/or the
effectiveness
of the
associated protective device. This
erificarion shall be tnade:
r
-
for overcurrent protective devices, by visual inspection or other appropriate methods (i.e. short-time or instantaneous tripping setting for circuit-breakers, cunent rating and type for fuses)
-
fbr RCDs, by visual inspection and testing.
test equipment The effectiveness of automatic disconnection of supply by RCDs shall be verified using suitable are according to BS EN 61557-6 (see Regulation 643.1) to confim that the relevant Iequilements ofChaptel4l met, taking into account the opemting characteristic ofthe device' See Table 3A in Appendix 3. NOTE: a point located downstream of an RCD, proved by confirmation of the continuity of the protection of the installation downstream from this point may be the protective conducto$.
where the effectiveness of the protective measure has been confitmed at
b) TT system Compliance with Regulation 411.5 shall be velified by: (l) measurement ofthe resistance ofthe eafih electrode for exposed-conductive-parts ofthe installation (see Regulation 643.7.2)
NOTE:
Where a measurement ofRA is not practicable the measured value ofextemal eafih fault loop impedance may be
(2)
uLscd.
verification ofthe chamcteristics and/or effectiveness ofthe associated protective device. This verification shall be urade:
-
for overcurrent protective devices, by visual inspection oI other applopriate methods (i.e. short-time oI instantaneous lripping setting for circuit-breakers, current rating and type for trses)
-
for RCDs, by visual inspection and lesting.
equipment The effectiveness of automatic disconnection of supply by RCDs shall be verified using suitable test 41 are of Chapter lequirements relevant that the (see I confiming 643. Regulation 55 7-6 ) according to BS EN 6l met, taking into account the operatilg characteristic ofthe device
NOTE:
Sce Table 3A in APpendix 3.
of an RCD, Where the effectiveness of the protective measure has been confirmed at a point located downstream of the continuity the protection of the installation downstream from this point may be ploved by confimation of the protective conductors.
c)
lT system
of the Courpliance with the requirements of Regulation 411.6 shall be verified by calculation or measurement curent 1a in case ofa flrst fault on a live conductor. Plecautions A measurement is [rade only if calculation is not possible because all the parameters are not known. fault' a double to shall be takel while maki;rg the measurement in order to avoid the danger due
Whele ln the case ofa double earth fault, the fault loop impedance shall be verifled by calculation or measurement (see TT system as for a made shall be (see 41), verification Chapter the condition is similar to that of a TT system by 41), verification (see Chapter a TN system to that of Regulation 643.7.1. item b)). Where conditions aIe similar measurement shall be made as follows:
(i) for.tT installations supplied from a local transformer, the earth fault loop impedance is measured by
(ii)
_234
insefiing a connection with negligible impedance between a live conductor and eadh at the origin of the installaion. The eafih fault loop impedarice measurernent is made between a second live conductor and protective earth at rhe end of the ciicuit. Verification is achieved if the measured value is < 50 % of ttre maximum allorved looP imPedance by verification ofthe for IT systems connected to a public griil, the earth fault loop impedance is detemined two live conducton between continuity ofthc protective concluctor and by measuring the loop impedance permitted maximum ofthe is 50 7o 3 at the end ofthe circuit. Verification is achieved ifthe measured vatue necessary' are loop in.rpedance. Ifverification is not achieved, more detailed measurements
643.7.2
Earthelectroderesistance
Where the eafthing system incoryorates all earth electrode as paft of the installation, the electrode resistarce to Earth shall be measured.
NOTE:
Where a measurement ofRA is not pmcticable, the measured value ofextemal earth fault loop impedance may be used.
643.7.3
Earth fault loop impedance
Where protective measures are used which require a knowledge of earth fault loop impedance, the relevant impedances shall be measured, or determined by an altemative method.
-{n electrical continuity test shall be carried out according to Regulation 643.2 before carrying out the eafth fault loop impedance measurement. The measured earlh fault loop impedance shall comply with Chapter
4l.
\\ihere the requirements of this regulation are not satisfied and supplementary protective equipotential bonding according to Chapter 4l is provided, the effectiveness ofthat bonding shall be verifled.
NOTE:
Further information on measurement of earth fault loop impedance can be found inAppendix 3.
643.7.3.20'l Prospective fault current The prospective
short-circuit current andprospective earth fault current shall be measured, calculated or determined o gin and at other relevant points in the installation.
c1 another method, at the
Additional protection
643.8
re verillcation ofthe effectiveness ofthe measures applied foradditional protection is fulfilled byvisual inspection 'rd tcsting. Where RCDs are required for additional protection, the effectiveness of automatic disconnection of .-.pply by RCDs shall be verilied using suitable test equipment according to BS EN 61557-6 (see Regulation i3. I ) to confim that the relevant requirements of Chapter 4l are met. -
NOTE:
Effectiveness is deemed to have been verilied where an RCD mccting thc rcquircmcnts of Regulation 415.1.1 disconnccts within 40 ms when tested at a current equal to or higher than five times its rated residual opertring current.
'i here additional protection is provided by supplementary protective ::t bonding shall be checked against thc rcquircments ofChapter 41. 6,43.9 Check of phase sequence
l. -a
equipotential bonding, the effectiveness
of
For polyphase circuits, it shall be verified that the phase sequence is maintained at all relevant points thmughout -he
installation.
643.10
Functionaltesting
aquipment shall be subjected to functional testing, as appropriate, to verilj/ that it is properly mounted, adjusted :nd installed and operates correctly in accordance with the relevant requirements of this Standard. Examples of :-'rch equipment are:
-
switchgear and controlgear assemblies, drives, controls and interlocks systems for emergency switching off and emergency stopping
insulation monitoring. XOTE 1: This list is not exhaustive.
l:otective devices shall be submitted to a test oftheir function,
as necessary, to check that they are properly installed adjusted. Where fault protection and/or additional protection is provided by an RCD, the effectiveness of any =d :.sr facility incorporated in the device shall be verified.
,\here an AFDD is installed the effectiveness olany manually operated test facility shall be verified in accordance
;
1th the
manufacturers' recommendations.
HOTE 2: This functional test does not replace the functional test indicated by the relevant standards. a4 3.1 '.
1
Verification of voltage drop
-ere required to verify compliance with Chapter 52, the voltage drop shall be elaluated by measurement or by
-..:ulation.
,l-.
235
NOTE:
Verification ofvoltage drop is notnonnally required during initial
6M
ve
fication.
CERTIFICATION FOR INITIAL VERIFICATION
644.1 Except where Regu)ation 644.4.201 applies, upon completion of the verificatjon of a new installation or an addition or altemtion to an existing installation, including the replacement ofa distribution board or consLrrner lnit, an Electricat Installation Certificate based on the model given in Appendix 6 shall be issued to the person ordering the work.
644,1,1
For a new installation, any defect or orrission revealed corected before the Certificate is issued.
du ng the inspection and testing
shall be
644.1.2 For an addition and/or altemtion to an existing installation, any defect or omission that will affect the safety ofthe addition or alteration that is levealed during inspection and testing shall be corrected before the Certificate is issued. NOTE:
Sec Regulation 132.16.
The person responsible for the addition or altemtion, or a person autho zed to act on their behalf, shall record on the Electrical lnstallation Certificate any other defects observed during the course ofthe works that may give dse
to danger. Not used 644.2 The Certiflcate shall include 644.3 - schedule(s) ofinspections, and - schedule(s) oftest results.
details ofthe extent ofthe work covered, and:
The schedules shall be based on the models in Appendix 6. The pcrson or peISons fesponsible 1br thc dcsign, colstructiol and veri6cation of the installation shall issue the Certiflcate, which takes account of their respective responsibilities, to the person ordering the work, together with the records mentioned ir Regulation 644.3.
644.4
The recommendation for the interval between initial verification and the flrst periodic inspection shall be recorded on the Certificate. Where electrical installatiou work does not include the provision ofa new circuit or replacement of distribution board or consumer unit. a Minor Electricat Installation Works Certificate, based on the model given in Appendix 6, may be provided for each circuit that has been added to or altered as an altemative to an Electrical Installation Certifi cate.
644-4.201
a
Electrical tnstallation Certificates and Minor Electlical Installation Works Certiflcates may be wdtte[ or electronic fonn. Regardless ofthe media used for original cefiificates o[ their copies. their authenticity and integdty shall be verified by a reliable process or method. The process or method shall also vedfy that any copy is a true copy ofthe original.
644.4.202
produced in any
644.5
Electrical tnstallation Cedificates and Minor Electrical Installation Works Ceftificates shall be compiled and signed or otherwise authenticated by one or more skilled persols, competent to ve fy that the requirements ofthis Standard have been met.
236
-l
CHAPTER 65 PERIODIC INSPECTION AND TESTING GENERAL
651
Where required, periodic inspection and testing of every electrical installatiol'l shall be carried out
651.1
in accordance with RegtLlations 651.2 to 651.5 il order to detennine, so far as is reasonably practicable, whethet the installation is in a satisfactory conditior tbr continued service. Wherever possible. the documeltation arising lrorr the initial cedification and any plevious periodic inspection and testing shall be taken into accoLlllt. Where no previous documentation is available, investigation ofthe electlical installation shall be undertakell prior to carrying out the periodic inspection and testilg. Petiodic inspection shall becar ed out without dismantling, or with partial disnrantling. as required, supplenented by appropriate tests and nleasurements fioln Chapter 64. to pl'ovide for: (i) the sat'ety ofpersons and livestock against the effects ofelectr-ic shock and bunts 651.2
iil
(ii) protectior against damage to property by fire and heat arising from an electdcal installation delect (iii) confirmation ofcorect rating and setting ofprotective devices required by Chapter 4l (iv) colfimation ofcorect rating a]td setting of monitoring devices (v) confirmation that the installation is not damaged or deteriorated so as to impair safety (vi) the identification of installation defects and non-compliances with the requirements ofthe relevant
palts of
BS 7671, that may give rise to darger. NOTE 1: A genelic list ofexamples of items reqLriring inspection is given in Appendix 6. NOTE 2; Existing installations may have been designed and installed to confonn to previous editiors of BS 767 I . applicable at the timc oftheir design and erection. This does not ecessarily ,rean that they arc Lusafe ,:lon
\\/here a circuit is pem]arently tnonitored by an RCM or an IMD resistance ifthe functioning ofthe RCM or IMD is coIrect.
.rk.
The
':ded
furctioling of
the RCM or
it is not
necessary to lneasure the insulatrorr
tMD shall be vcrified.
Pcriodic inspection and testing shall not cause danger to persons or livestock and shall not cause danage to propcdy or equipment even ifthe cicuit is defective. 651.3
lir of :l\
en
:::icai
\leasuring instruments and monitoring cquipment and methods shall be chosen in accordance with the releva[t parts of BS EN 6 I 55 7. If other rneasuring cquipment is used, it shall provide no less a degree of perlbrmance and safety.
:\
651.4 651.5
,-
bc
lies. . llso
The periodic inspectior and testing shall be carried out by one or more skilled persons competent in
such work.
652 -..'.i1
Details ofany darlage, deterioration, defects or dangerous conditions shall be recolded in a report.
be
FREQUENCY OF PERIODIC INSPECTION AND TESTING
652.1 The ti-eqr.rency ofperiodic inspection and testing ofan installation shatl be detemrined having regard :!r rhe type ol installation and ecluipment, its use and operation, the frequency and quality of rnaintenance and the :rrenal influences to which it may be subjected. The results and recommendations of previous certiflcates and .ondition repofis shall also be takel into account.
:,..I the
652.2 ln the case of an installation under an effective management system fol plel entilti\ e lnajrrtenance ill :onnai usc, periodic inspection and testing may be leplaced by an adequate regime ol continuous monitoring and maintenance of tlte installation and all its constituent equipmelrt by olle or more skilled persons conpetent * olk. Appropriate records shal1 be kept.
653
i11
such
REPORTING FOR PERIODIC INSPECTION AND TESTING
3.'l upon completion of the periodic inspection and testing of an existing installation, an Electrical I:rstallation Condition Repoft based or tlre model given in Appendix 6 shall be produced. 65
653.2 The Report shall include the following: - details ofthose pafts oftbe installation that have been inspected and tested - any limitatioos ofthe inspection and testing - ally darnage. detcrioration, defects or dangercus conditions - any non-co[rpliance with the requirements ofBS 7671 which firay give rise to darger &-
- schedules ofinspection as appropriate - schedules ofresults ofthe apprcpriate Not Ltsed 653.3
to those detailed in Section 642 tests detailed in Section 643
supported by an The Repot shall indicate a recommended interyal until the next inspection'
cxplanatiol lor the recomm
en.la t iott.
653.5TlreReponshallbecompiledandsigrredorotherwiseauthenticatedbyoneormoleSkilledpersons competent in such work.
testing' The Report shall be issued to the person ordering the inspection and
t
PART 7
SPECIAL INSTALLATIONS OR LOCATIONS CONTENTS
700
GENERAL
70'l
LOCATIONS CONTAINING A BATH OR SHOWER
702
SWIMMING POOLS AND OTHER BASINS
703
ROOMS AND CABINS CONTAINING SAUNA HEATERS
704
CONSTRUCTION AND DEMOLITION SITE INSTALLATIONS
705
AGRICULTURAL AND HORTICULTURAL PREMISES
706
CONDUCTING LOCATIONS wlTH RESTRICTED MOVEMENT
708
ELECTRICAL INSTALLATIONS IN CARAVAN / CAMPING PARKS AND SIMILAR LOCATIONS
709
MARINAS AND SIMILAR LOCATIONS
7',to
MEDICAL LOCATIONS
7',t1
712
EXHIBITIONS, SHOWS AND STANDS SOLAR PHOTOVOLTAIC (PV) POWER SUPPLY SYSTEMS
7',t4
OUTDOOR LIGHTING INSTALLATIONS
715
EXTRA.LOW VOLTAGE LIGHTING INSTALLATIONS MOBILE OR TRANSPORTABLE UNITS ELECTRICAL INSTALLATIONS IN CARAVANS AND MOTOR CARAVANS ELECTRIC VEHICLE CHARGING INSTALLATIONS OPERATING AND MAINTENANCE GANGWAYS ONSHORE UNITS OF ELECTRICAL SHORE CONNECTIONS FOR INLAND NAVIGATION VESSELS TEMPORARY ELECTRICAL INSTALLATIONS FOR STRUCTURES HEATING CABLES AND EMBEDDED HEATING SYSTEMS
717 721 722
729 730 740 753
SECTION
7OO
GENERAL .. e particular requirements for each section (special installation or location) in Part 7 supplement or modify the ::reral rcquirements contained in other parts ofBS 7671. -
-',r absence
ofreference to the exclusion of
::reral regulations
a
pafi,
a
chapter, a section or a regulation means that the corresponding
are applicable.
- : number ,
appearing after a section number generally refers to the corresponding chapter, section or regulation to 6. The numbering does not, therefore, necessarily follow sequentially and new numbers have been as required. Numbering offigures and tables takes the number ofthe section followed by a sequential number.
::1in Parts
-:ed
I
I
239
SECTION 701 LOCATIONS CONTAINING A BATH OR SHOWER Scope
701.1
The pafticular requirements of this section apply to the electrical ilstallations i]1 locario:-: (bath tub. birthing pool) o[ shower and to the sunounding zones as described lr] rhe:e r:-,
. ::;: ": , i\ed bath
Thissectiondoesnotapplytoemeryencyfacjlitiessuchasemergencyshowersusedinir.:-..:
-:-:-, :
-.
jr(irarories.
701.3 Assessment of general characteristics 70'1.32 Classificationofexternalinfluences 701.32,1
General
When applying this sectior the zooes specified ir Regulations 701.32.2 ro,1 shall bi:-,::: prefabricatedbathorshowerunits,thezonesareappliedtothesituatiol\\'i']enrhr-.::: usable configuration(s).
:: .-- -:::. For fixed :: :.::..:r is in its
Horizonlal or inclined ceilings, walls withor without windows, doors, floors ancl firec:.:::: acCountwheret1reseel1'ectiVe1ylimitt1reextentof1ocationscontainingabathor.h.,,:.
: :r:. :.'irlken into
Where the djmensions offixed partitions are smaller than the dimensions of the r;l:.::: ....: prirlitious having a height lowerthan2.25 m,theminimurn distance in tlre horizontal and\errical d.::::: ::: : .... rj itken into accourt (see Figures 701.1 and 701.2).
ForelectricalequipmentinpaftsofwallsorceilingslimitingthezonesspecifiedinRes:--:::-::.-.:l.lro4,but :lpl..
being part ofthe surface ofthat u,all or ceiling, the r.equirements tbr the respective zone
701.32.2
Description of zone 0
Zonc 0 is the interior of1hc bath tub or shower basin (see Figurcs 701.1 and 2). For showers without a basin. the height of zole 0 is zone 1 (see Figure 701.2(fl).
701.32.3 Zonc
1
(i) (ii)
Description of zone
0.
l0 m and its surlace extcnt
has the sauta horizoltal exlcnt as
1
is limited by:
the finished floor level ald the horizontal plane coresponding to the highest fised shern er l1ead or water outlet or the ho zontal plane lying 2.25 rn above the finislred floor level. whicher.er is hieher the vertical surface:
(a) circumscribing the barh tub or shower basin (see Figure 701.I ) (b) at a distalce of 1.20 m ftom the centre point ofthe fixed water outlet on the \.vall or ccilins 1br showers without a basin (see Figure 701.1(e) and (f)). Zone
I
does not include zone 0.
The space under the bath tub or shower basin is considered to be zone l. However, if the space uncler the bath fttb or showcr basin is only accessible with a tool, it is considered to be outside the zones.
701.32,4
Description of zone 2
Zone 2 is linited by:
(i) (ii)
the Iinished floor level and the horizontal plane corresponding to the highest fixeil shower head or water outlet or the horizontal plare lying 2.25 m above the finished floor level, whichever is higher the vetical surface at the boundary ofzone the zone I border (see Figure 701.l ).
I
and the parallel veftical surface at a distance 010.60 m from
Fot shorvers without a basin, there is no zone 2 but an increased zone I is provided by the horjzontal dimension of 1 .20 m mentioned in Regulation 701.32.3(ii)(b) (see Figur e 701.1(e) and (t)).
240
701.41
Protection for safety: protection against electric shock
701.410.3 Generalrequirements 701.410.3.5 The prorective measules of obstacles and placing out of reach (Section 417) shall not be used. 701.410.3.6 The protective measures of non conducting location (Regulation ,118.1) and earth-flee local equipotential bonding (Regulation 418.2) shall not be used.
701.411.3.3 Additional protection by RGDs Additional protectior by the use of one or more RCDs having the charactedstics specifred in Regulation 415.1.1 shrll be pror ided lor lou roltage circuits:
(i) (ii)
serving tlrc location passing through zones 1 and/or 2 not serying the locatior.
NOTE: SeealsoRegulationsIl4.l(iv)and531.1 1,:i
701.413
2 conceming the avoidance ofunwanted
tippiDg'
Protectivemeasure:Electricalseparation
Protection by elcctrical separation shall only be used for:
(i) (ii)
:l
circuits supplying one item ofcurent-using equipment, or one single socket-outlet.
For electric floor heatirg systems, see Regulation 701 753.
::r
Protective measure: Extra-low voltage provided by SELV or PELV 701 .4'14.4.5 Requirements for SELV and PELV circuits
701.414
\\'hele SELV or PELV js used, whatever the nominal voltage, basic protection for equipment in zones 0,
I
and 2
.hall be provided by:
(i) (ii)
basic insulatiot complying with Regulation 416.1, or
bauiers or enclosures cornplying rvith Regulation 416.2.
701.415 Additionalprotection 701.4'15.2 Supplementary protective equipotential bonding Regulation 415.2 slrall be established corutecting -Jcal supplementary protective equipotential bonding according to to the : rsether the terminals of the protective conductor of each cit'cuit supplying Class I and Class II equipment the following: including ,:.essible exkaneous-conductive-parts, within a room containing a bath or showcr,
(i) rii) rii)
metallic pipes supplying services and netallic waste pipes (e.g. water, gas) metatlic central heating pipes and ait conditioning systems accessible rretallic stluctuml parts of the building (nietal]ic door architraves. wiudow fiames and sitnilar pafis are not considerecl to be extraneous-conductive-pafis ulrless they are connected to metallic structural parts ofthe building).
:,:plementary protcctive equipoterrtial bonding [ray be installed outside or inside rooms col]tail-Iing a bath or
-
.rer. preferably close to the point of entry of extaneous-conductive-pafis into such tooms
jre the locatioll containilg a bath or showel is in a building with a protective equipotential bonding system in -,,: idance with Regulation 4l 1.3.1.2, supplementary protective equipotential bonding may be omitted where all of -
.-. -ollorving conditions are met: . r All final circuits of the location comply with the requirements for automatic disconnection according to Regulation 411.3.2 .
r
A11
final circuits of the location have additional protectior by means of an RCD in accotdalce with
Regulation 415.1.1
r, -{ll extmneous-conductive-pa
s of the location are effectively connected to the protective equipoterltial 41 I.3.1 2 to Regulation bonding according
iCTE;
The effcctiveness ofthe co tection ofexhancous conductivc-parts in the locatjon io lhe main earthing tenniDal ma\ be assessed, where necessary. by the applicatiorr ofReglrlation 415.2.2.
701.5
Selection and erection of equipment
701.512.2 External influences Installed electrical equipment shall have at least the following degrees ofprotection:
(i) h zone 0: IPXT (ii) Il zones I and 2: IPX4. This requirement does not apply to shaver supply units comptying with BS EN 61558-2-5 installed in zone 2 and located where direct spmy from showers is unlikely.
Elect cal equipment exposed to waterjets, e.g. for cleaning pulposes, shall have
a degree of protection
ofat least
IPX5.
701.5'12.3 Erection of switchgear, controlgear and accessories according to external influences The following requirenents do not apply to switches and controls which are incorporated in fixed curenlusing equipment suitabie for use in that zone or to insulating pul1 cords ofcord operated switches. In zone 0: switchgear or accessories shall not be installed.
In zone
I
:
only switches of SELV circuits supplied at a nominal voltage not exceeding l2 VAC lms or 30 V dpple-free DC shall be installed, the safety source being installed outside zones 0, I and 2.
ln zone
2'.
switcl'rgea[, accessories incorporating switches or socket-outlets shall not be installed with the exception of:
(i)
switches and sockeGoutiets of SELV circuits, the salety source being installed outside zones 0, 1 and 2, and
(ii) shaver supply units complying with BS EN 61558-2-5. Except
for SELV
socket-outlets complying
with Section 414 and shaver supply units complying with of3 m hodzontally from the boundary ofzone l.
BS EN 61558-2-5, socket-outlets are prohibited within a distance
701.55
Current-usingequipment
ln zone 0, current-using equipment shall only be installed provided that all the following requirements are met:
(i) (ii) (ili)
The equipment complies with the relevant standard and is suitable for use in that zone according to the malufacturer's instructions for use and mounting The equipment is fixed and permanently connected The equipment is protected by SELV at a nominal voltage not exceeding l2 V AC rms or 30 V ripple-free DC, the sat'ety source being installed outside zones 0, 1 and 2.
In zone l, only the lbllowing fixed and perrnanently connected current-using equipment shall it is suitable for ilstallation in zone I according to the manufacturer's instructions:
(iv) (v) (vi) (vii) (viii) (ix) (x) (xi)
242
be installed, provided
Whirlpool units Electric showers Shower pumps Equipment protected by SELV or PELV at a nominal voltage not exceeding 25 VAC rms or 60 V ripple-free DC, the sat'ety source being installed outside zones 0, I and 2
Ventilationequipment Towel rails Water heating appliances
Luminaires.
I 701.753
Electric floor heating systems
For electric floor hcating systelns, only heating cables accordins to rr-li, -,::: :':. :.-.': .rrndards ol thin shcet flexible heating elements according to the relevant equipment standard shall be ere;:;; ::r'. :red tliat they havc either a metal :heathorametalenr'losursorafinemeshrnetallicgrid.Thefinerneshmet;i:;=::;.r:r.'r.rl sheath or tnetal enclosule shall be courected to the protective cotrductor of the supply circuit. Compli,rn;r .'. :ih thr latter require[rent is not required ifthe protective measure SELV is provided for the floor healirlg s\ s{iu: For electric floor heating systems the plotective measure 'protection by electli!'al sij.ilratlon' shall not be used.
Fig 701 .1 - Examples of zone dimensions (plan) NOT TO SCALE (See Regulation 701.32 for definitions ofzones) a) Bath tub
b) Bath tub, wiih permanent fixed partition
c) Shower basin
d) Shower basin with permanent fixed partit on
: .- ::. s = thickness of partition
e) Shower, wlthout bas n
0 Shower, without basin, but with permanenifixed partition
s = thickness of parttion y = radial distance from ihe
fixed water outlet to the nner corner of the paalition
Fi9701.2- Examples of zone dimensions (elevation) NOT TO SCALE (See Regulation 701.32 for deflnitions ofzones) a) Bath tub
c)Shower basin
f) Shower without basin, but with permanent fixed partition Section x-x, see Fig 701.1f) Ceiling Ouls de zones
Outside zones
zare 2 2.25 m zone 0
0
Permanent partition
* Zone
1 if the space is accessible without the use ofa tool. Spaces under the bath accessible only with the use ofa tool are outside the zones.
244
SECTION 702 SWIMMING POOLS AND OTHER BASINS 702.1
Scope, object and fundamental principles
702.11
Scope
The particular requirements of this section apply to the basins ol swimming pools, the basins of fountai[s and the basins ofpaddling pools. The paticular requirements also apply to the surounding zoncs of these basins.
ln tllese areas, in nomal use, the risk ofelectric shock is increased by a reduction in body resistance ard contacl ol fie body with Earth potential. Swimming pools within the scope of an equipment standaid are outside the scope of these regulations.
E\cept for areas especially designed as swimming pools, the requirernents of this section do not apply to naturai saters, lakes in gravel pits, coastal areas and the like.
702.3 Assessment of general characteristics 702.32 Classification of external influences These requirements are based on the dimensions ofthree zones (exampres are given in Figures 702.1 to 4).
Zones
I
and 2 may be lin.rited by fixed partitions having a minirrum height of 2.5 m.
(i) Zone 0 This zone is the interior ofthe basin ofthe switrming pool or fountain including any recesses in its walls or floors. basins for foot cleanirrg 6nd waterjets or waterfalls and the space belorv them.
(
ii) Zone I This zone is limited by:
-
zone 0 a
verlical plane 2 m from the rim of the basin
the floor or surface expected to be occupied by persons the horizontal plate 2.5
n
above the floor or the surface expected to be occupied by persons.
:re the swimming poor or fountain contains diving boards, springboards, starting blocks, chutes or otrrer -::ronentsexpectedtobeoccupiedbypersols,zonelcomprisesthezonelimitedby:
-
a veftical plane situated 1.5 m rrom the periphery ofthe cliving boards, chutes and other colllponents such as accessibre icurptures, viewing
-
the horizontal plane 2.5 tn above the highest surface expected to be occupied by pe$o[s.
iiit Zone
sp ngboards, sradng blocks. bays anJ decorative baJns
2
This zone is linrited by:
-
the
vetical plane extenlal to zone I and a parallel plane
1.5
m f-rotn the fonaer
the floor or sudhce expected to be occupied by persons the horizontal plane 2.5 m above the floor or suttace expected to be occLrpied by persons.
There is no zone 2 for fountains.
Protection for safety
0.3
Generalrequirements
0.3.4 Application of protective measures against electric shock
.4.1
Zones 0 and
1
: rbuntains as stated in Reguration 702.1r0.3.r.2. in zonc 0 only prorecrior br SELV lr r norninrl vortalre or 30 V ripplc-t'r'ee DC is pernittcd. the souice for SELv teing i,rr,"iiJ;.;;rl;;;;;:,
'.;rng l2 v AC rns
Except for fountains as stated in Regulation 702.410.3.4.2, in zone 1 only protection by SELV at a nominal voltage not exceeding 25 V AC mrs or 60 V ripple-free DC is permitted, the source for SELV being installed outside zones
0, I and 2.
inte or ofbasins which is only intended to be in operation when people are not inside zone 0 shall be supplied by a circuit protected by: Equipment loruse in the
(i) (ii)
SELV (Section 414), the source for SELV being installed outside zones 0, 1and2. However, it is permitted to install the source for SELV in zone 2 ifits supply circuit is protected by an RCD having the characteristics specified in Regulation 415.1.1, or
Automatic discoruectior of supply (Section Regulation
(iii)
41 5.
1
4ll),
using an RCD having the chamcteristics specified in
.1, or
Electrical separation (Section 413), the source for electrical separation supplying only one item ofcurrentusing equipment and being installed outside zoues 0, 1 and 2. However, it is pemitted to install the source in zone 2 if its supply circuit is protected by an RCD having the characteristics specified in Regulation 415.1.1.
Thc sockeloutlet ofa circuit supplying such equipment and the control device of such equipment shall have a notice in order to wam the user that this equipment shall be used only when the swimming pool is not occupied by persons.
702.410.3.4.2 Zones 0 and 1 of fountains In zones 0 and 1, one or more ofthe following protective measures shall be employed:
(i) (ii)
SELV (Section 414), the source for SELV being installed outside zones 0 and I
Automatic disconnection of supply (Section 411), using an RCD having the charactedstics specified in Regulation 415.1.1
(iii)
Electlical separation (Section 413), the source for electrical separation supplying only one item ofcurentusing equipmcnt and being installed outside zones 0 and
1.
702.410.3.4.3 Zone 2 One or more ofthe tbllowing protective measures shall be employed:
(i)
SELV (Section 414), the source for SELV being installed outside zones 0, 1 and 2. However, it is permitted to install the source for SELV in zone 2 ifits supply circuit is protected by an RCD having the characteristics specified in Regulation 415.1.1
(ii)
Automatic disconnection of supply (Section 411), using an RCD having the characteristics specified in Regulation
NOTE:
(iii)
415.l.l
Where a PME earlhing facility is used as the means ofearthing for the electrical installation of a swimming pool ot other basiL it is recommended that an earth mat or earth electrode of suitably low resistance. e.g. 20 ohms or less, be installed and connected to the supplementary protective equipolential bonding.
Electrical sepamtion (Section 413), the source for electrical separation supplying only one item of currentusing equipment and being installed outside zones 0, I and 2. Howeveq it is permitted to install the source in zone 2 ifits supply circuit is protected by an RCD having the characteristics specified in Regulation 415.1.1.
There is no zone 2 for fountains.
702-410.3.5 The protectivc
measures of obstacles and placing out ofreach (Section 417) shall not be used.
702.410.3.6 The protective measures of ron-conducting location (Regulation 418.1) and earth-free local equipotential bonding (Regulation 418.2) shall not be used.
702.4'14
Protective measure: Extra-low voltage provided by SELV or PELV
702,414.4 Requirements for SELV and PELV circuits 702,4'14,4,5 Where SELV is used, whatever the nominal voltage, basic protection shall (
(i) ii)
be provided by:
basic insulation cornplying with Regulation 416.1, or bariers or enclosures complying with Regulation 416.2.
702.415
Additionalprotection
702,415.2 Additional protection: Supplementary protective equipotential bonding All extraneous-conductive-parts in zones 0, I and 2 shall be connected by supplementary protective bondins conductors to the protective conducton of exposed-conductive-parts of equipment situated in these zones. rr accordance with Regulation 4l 5.2.
246
NOTE: Theconnectionwilhlheprotectiveconductormaybeprolidedinrhcprorimii.,oflhclocarion,e.g.inanaccessorlor in a local distribution board.
702.5 Selection and erection of equipment 702.51 Common rules 702.512
Operational conditions and external influences
702.512.2 External influences Electrical equipment shall have at least the following degree ofprotection accordiDg to BS EN 60529:
(i) (ii) (iii)
zone 0: lPX8
zonel:IPX4. IPX5 where waterjets
are likely to occur for cleaning purposes
zone2: IPX2 for indoor locations, IPX4 for outdoor locations, IPX5 where water iets are likelyto occur for cleaning putposes.
702.52
Wiring systems
702.520
General
The lollowing regulations apply to sudace wiring systems ard to wiring systems ernbedded ilools at a depth not exceeding 50 mm.
702.522
i[
the walls, ceilings or
Selection and erection in relation to external influences
702.522.21 Erection according to the zones In zones 0, I and 2, any metallic sheath or metallic covering ofa wir ing system shall rrotective equipotential bonding.
NOTE:
Cables should preferably be iDstalled in conduits made
be connected to the
supplementary
of iDsulating .laterial.
702.522.22 Limitation of wiring systems according to the zones -:
zones 0 and
l, a wiring system shall be limited to that
necessary to srLpply cquipment situated in these zones.
702.522.23 Additional requirements for the wiring of fountains aor a fountain, the following additioflal requirenents shall be met:
ti) ,
ii)
A cable for electrical equipment in zone 0 shall be installed as far outside the basin m as is reasonably practicable and run to the electrical equipment inside zone 0 by the shoftest pmcticable route In zone 1, a cable shall be selected, installed and provided with mechanical protection to medium severiry (AG2) and the relevant submersion in water depth (AD8). The cabte type H07RN8-F (BS EN 50525-2-21) is suitable up to a depth of 10 m ofwater. For depths olwater greater than 10 m the cable lranufacturer shall be consulted.
-
02.522.24 Junction boxes
-
-:
--Lnctior
box shall not be installed in zones 0 or
,-:s in zone
l,
except that
fol SELV circuits it is pemritted to install j unction
1.
Protection, isolation, switching, control and monitoring -,res 0 or
I, switchgear or controlgear sirall not be installed.
res 0 or l, a socket-outlet shall not be installed.
' ri l. a socket-outlet -- :.'tir'e lreasures:
or a switch is permitted only where tlre sLrpply circuit is protected by one ofthe lollowing
SELV (Section 414), the source ofSELV being installed outside zones 0. L and 2. However, it is pemitted 10 install tl]e soutce ofSELV ir zone 2 ifits supply circuit is plotected by an RCD haviug the chalacreristics specified in Regulation 415.1.1
\utomatic disconnection of supplv (Section 411). usi[g an RCD hurinc Resulation 415.1 .l
-.-,t--
rhc- char:acteristics
specified in
(iii)
Electrical separation (Section 413), the source for eleclrical separatior supplying only one item ofcurentusing equipment, or one socket-outlet. and being installed outside zones 0, 1 and 2. However, it is permitted to install the source in zonc 2 if its supply circuit is plotected by an RCD having the characteristics specified in Regulation 415.1.1.
For a swimming pool where it is not possible to locate a socket-outlet or switch outside zone l, a socket-outlet or switch, preferably having a non-conductjve cover or coverplate, is pemritted in zone t if it is installed at least 1.25 m horizontally from the border ofzone 0. is placed at least 0.3 m above the floor, and is protected by:
(iv)
SELV (Section 41.1), at a nominal voltage not exceeding 25 V AC rms or 60 V dpple-free DC. the source for SELV being installed outside zones 0 and i . or
(v)
Automatic disconnection of supply (Section 411). using an RCD having the characteristics specified in Regulation 415.l. t, or
(vi)
Electrical separatjon (Section 413) fbr a suppty to only one item ofcurrent-using equipment, the source for electrical separation being installed outside zones 0 and l.
702.55
Other equipment
702.s5.1
Current-using equipment of swimming pools
In zones 0 and 1, it is only pennitted to instail fixed cunent-using equipment specifically designed lor use in
a
swimming pool, in accordance with the lequircments of Regulatiols 702.55.2 and702.55.4. Equipment which is intended to be in operation only when people are outside zone 0 may be used in all zones provided that it is supplied by a circuit protected according to Regirlation 702.410.3.4.
It
is permitted to install an electric heating unit embedded in the floor, provided that it:
(i)
is protected by SELV (Section 414), the source of SELV being installed outside zones 0, 1 and 2. However, it is pemitted to install the source of SELV io zone 2 if its supply circuit is protected by an RCD having the
characteristics specified in Regulation
z[
15.1.1. or
(ii)
incorporates an earthed metallic sheath collnected to the supplementary protectiye equipotential bonding specifled in Regulation 702.415.2 and its supply circuit is additionally protected by an RCD having the characteristics specified in Regulation 415.1.1, or
(iii)
is covered by an embeddcd caflhcd mctallic grid connected to the supplemenlary protective equipotential bonding specified in Regulatior 702.415.2 and its supply cilcuit is additionally protected by an RCD having the chamcledstics specified in Regulation 415.1.1.
702.55.2
Underwater luminaires for swimming pools
A luminaire for use in the water or in contact with the u,ater shall be fixed aud shall comply with BS EN 60598-2-t 8. Undelwater lighting locatedbehind watertight poftholes, and sewiced from behind, shall comply with the appropriate palt of BS EN 60598 and be installed in such a way that no intentional or unintentional conductive connection between any exposed-conductive-par1 of the underwater luminaires ald any conductive parts of the poftholes can
occut
702.55.3
Electrical equipment of fountains
Electrical equipment in zones 0 or
I
shall be provided with rnechanical protection to mcdium seve ty (AG2),
e.g. by use of mesh glass or by grids which can only bc removed by the use ofa tool.
A luminaire installed in zones 0 or
1 shall be
lixed and shall comply with BS EN 60598-2-18.
An electric pump shall comply with the requircnents of BS EN 60335-2-41
.
702.55.4 Special requirements for the installation of electrical equipment
in zone 1
of
swimming pools and other basins Fixed equipment designed for use in suilrrning pools and other basins (e.g. filtlation systems, jet stream pumps) and supplied at low yoltage is pemitted in zone l, subject to all the following requirements being met:
(i)
248
The equipment shall be located inside an insuJating enclosure providing at least Class insulation and providing protection agajnst mechanical impact of medium severity (AG2)
II or equivalent
This regulation applies irespective olthe classification olthe equipmeni.
tent-
(ii)
ined
ified
(iii)
'ut1et
The equipment shall only be accessible via a hatch (or a door) b\ means ofa key or a tool. The opening ol the hatch (or door) shall disconnect all live conductors. The suppll cable and the main disconnecting means sha11 be installed in a way which provides protection ofClass II or equir alent insulation The supply circuit ofthe equipment shall be protected by:
least
re
SELV at a nominal voltage not exceeding 25 V AC being installed outside zones 0, I and 2, or
ibr
sour.ce
of SELV
an RCD having the characteristics specified in Regulation 415. i.1. or
I
-
rd in :e
ms or 60 \- ripple-free DC, the
electrical separation (Section 413), the source for electrical separation supplying a single fixed item curent-using equipment and being installed outside zones 0, I and 2.
of
Fot'swimming pools where there is no zone 2, lighting equipment supplied by othel than a SELV source at 12 V AC rms or 30 V pple-ftee DC may be installed in zone I on a wall or on a ceiling. provided that the following
for
requirements are fulfi lled:
rina
-
The circuit is protected by automatic disconnection ofthe supply and additional protection is provided by an RCD having the characteristics specified in Regulation 4l 5. I .1
-
The height from the floor is at least 2 m above the lower limit of zone
In addition, every luminaire shall have an enclosure providing Class protection against mechanical impact of mediuln severity.
zones
i a\'el'.
:j
the
,:'.ling
:S
the
::nlial :-,r ing
f
-l-
18.
i:r'int"".
i,'ti1.)ll
:.
C
irtl
Gl
).
Il
l.
or equivalert insulation and providing
l-
c
I
I
Qc{
I
E'
i o o-
E
oo >N
:
=C
I
.e
I
L__
I
__Y
E
o
o o I
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SECTION 703 ROOMS AND GABINS CONTAINING SAUNA HEATERS Scope
703.1
The particular requirements ofthis section apply to:
(i) (ii)
sauna cabins erected on site, e.g. in a location or in a room the roorr where the sauna heater is, orthe sauna heating appliances are installed. In this case thewhole room is considered as the sauna.
The requirements of this section do not apply to prefabdcated sauna cabins complying with a relevant equipment standard. Where lacilities such as showers etc. are installed, the requirements of Section 701 also apply.
703.3
Assessment of general characteristics
703.32
Classification of external influences
When applying these regulations, the zones specified in Regulations 103.32.1 to 3 shall be taken into account (see also Figure 703).
703.32.'l
Description of zone
1
Zone I is the volume containing the sauna heater, limited by the floo1 the cold side ofthe thermal insulation ofthe ceiling and a vertical snrface circumscribing the sauna heater at a distance 0.5 m fiom the surface ofthe heater lfthe sauna heater is located closer than 0.5 m to a wall, then zone I is limited by the cold side ofthe thermal insulation
ofthat wall.
703.32.2
Description of zone 2
Zone 2 is the volume outside zone l, limited by the floor, the cold side ofthe themal insulation ofthe walls and a horizontal suface located 1.0 m above the floor.
703.32.3
Description of zone 3
Zone 3 is the volume outside zone 1, limited by the cold side ofthe thermal insulation ofthe ceiling and walls and a horizontal surface located 1.0 m above the floor
703.41
Protection against electric shock
703.410.3 General requirements 703.410.3.5 The protective
measures ofobstacles and placing out ofreach (Section 417) shall not be used.
703.410.3.6 The protecti!,e measures of non-conducting location (Regulation 418.1) and earth-free local equipotential bonding (Regulation 418.2) shall not be used. 703.411.3.3 Additional protection by RCDS Additional protection shall be provided for all circuits of the sauna, by the use of one or more RCDs having the characteristics specified in Regulation 415.1.1. RCD protection need not be provided for the sauna heater unless such protcction is recomrnended by the manufacturer.
703.4'14
Protective measure: Extra-low voltage provided by SELV or PELV
703.414.4.5 Whcre SELV or PELV is used, whatever the nominal voltage, basic protection shall
(i) (ii)
basic insulation complying with Regulation 416.1, or barriers or enclosures complying with Regulation 416.2.
703.51
Selection and erection of equipment: Common rules
703,512,2 External influences The equipment shall hare a degree ofprotection ofat least IPX4.
be provided by:
Where cleaning by use of water jets rnay be reasonably expected. electrical equipment shall have a degree protection ofat least lPX5.
of
Tlu-ee zones are defined as shown in Figure 703:
(i) (ii) (iii)
In zone
l: only
the sauna heater and equipment belonging to the sauna heater shall be installed
In zone 2: there is no special requirement conceming lteat-resistance of equipment tn zone 3: the equipment shall withstand a nrinimum tempelature of 125 "C and the irsulation and sheaths of cables shall withstand a minimum temperature of 170 oC (see also Regulation 703.52 for wiring).
703,52
Selection and erection of equipment: Wiring systems
The wiring system should be preferably ilstalled outside the zones, i.e. on the cold side of the thermal insulation. Where the wiring system is installed on the warm side of the thennal insulation in zones 1 or 3, it shall be heatresisting. Metallic sheaths and metallic conduits shall not be accessible in normal use.
703.53
Selection and erection of equipment: lsolation, switching, control and accessories
703.537,5
Switchgear and controlgear which forms palt of the sauna heater equipment or of other fixed equipment installed in zone 2, may be installed within the sauna roour or cabin in accordance with the [ranufacturer's instructions. Other switchgear and contolgear, e.g. for lighting, shall be placed outside the sauna room or cabin. Socket-outlets shall not be installed within the location containing the sauna heater.
703.55
Other equipment
Sauna heating appliances shall con.rply
withBS EN 60335-2-53
and be installed in accordance
with the manufactwer's
i[structions.
::re :1ie
Fig 703
:Lr11
-
zone dimensions for a sauna
ELEVATION I I I I I I I I I I
nda
i ald
I I I I
I I I I I I
local
ing the unless
..d
I I
ll
I
I
1
zone 2
1m
I
I I I I I I I I
I I I I I
zone
-
PLAN
iI bY:
zone 3
zone 2 and
zone 3
0.5 m
E ectrical connect on enc osure
Thermal insulation
SECTION 704 CONSTRUCTION AND DEMOLITION SITE INSTALLATIONS NOTE: Ifthe
704.1
PME earthing facility is considered lor use. scc also BS 7375.
Scope
704,'1.1 The particular requirements of this section apply to tempoBry installations for construction and demolition sites durirg the period of the construction or demoiition work, including. for example, the following: (i) (ii) (iii) (iv) (v)
construction work ofnew buildings repair, alteration, extension or demolition of existing buildings or pans of existing buildings
engineeringworks earthworks
work of similar nature.
The requirements apply to fixed and movabie instailatiotrs.
This section does not apply to installations in administrative locations ofconstruction sites (e.g. olflces, cloakrooms, meeting rooms, canteens, restaruants. dormitories, toilets), where the general requirements of Pafis I to 6 apply. 704.'l .2 For special situations, further pafiicular requiremcnts apply, e.g. Section 706 for conducting locations with resbicted movement.
704.31
Purposes, supplies and structure
704.313
Supplies
Equipment shall be identified with and be compatible with the particular supply liom which it is energized and shall contain only conrponcnts connected to one and the same installation, except for control or signalling circuits and inputs from standby supplies.
704.313.3 NOTE:
A single comh'Llction sitc may be served by several sources ofsupply, e.g ptlblic supply and gencmting set.
704.4 Protection for safety 704-41 Protection against electric shock 704.410
lntroduction
704.410.3 General requirements 704.410.3.5 The protective
measures ofobstacles and placing out ofreach
704.410.3.6 The protective
measures of:
-
(Section4l7) shall notbeused.
non-conductinglocation, earth-ftee equipotentiai bonding, and
electrical separation
for the supply of more than one curent-using
equipment as specified in
Regulation 418.3 shall not be used. a socket-outlet with a mted cuffent up to and including 32 A and any other circuit supplying hand-held electrical equipment with r-ated current up to and including 32-A shall be protected by:
704.410.3.10 A circuit supplying
(i) (ii)
Reduced low voltage (Regulatiorr
(iii)
electrical separation ofcircuits (Section4l3). each socket-outlet and item ofhand-held electriqal equipment being supplied by an individual tralsfonrct ot by a separate winding ofa transformer, or
(iv)
SELV or PELV (Section 414).
,11
L 8),
or
automatic disconnection ofsupply (Section 411) with additional protection providedby an RCD having the charactedstics specified in Regulation 415.1.1, or
Where electrical separation is used, specjal attertion should be paid to the requirements of Regulation 413.3.4. NOTE 1: The reduced low voltage system is stlongl.v prefcred for thc supply to porable handlamps fol-gercl al use and portable hand tools and local lighting up to 2 kW.
NOTE 2: The SELV system is strongl! plefened for poltable handlan:rps in corfined ot damp locations.
_
256
704.4'11
Protective measure: Automatic disconnection of supply
704.411.3 Requirements for fault protection 704.4'11.3.'l A PME earthing facility shall not be used for the means ofeafihing for an installation falling within thc scope ofthis section unless all extraneous-conductive-par1s are reliably connected to the main eafihing terminal in accordance with Regulation 411.3.1
NOTEI llthe
.2.
PME earthing facility is considered for use. see also BS 7375.
704.411.3.2 Automatic disconnection in case of a fault 04,4'l'1.3.2,1 For any circuit supplying one or firore socket-outlets with a rated current exceeding 32 A. Regulation 411.3.2.5 is not applicable. For any circuit supplying one or more socket-outlets with a rated current exceeding 32 A. an RCD having a rated residual operating current not exceeding 500 mA shall be provided
7
I
I I
to automaticall), intempt the supply to the line conductors of a circuit or equipment in the event of a fault of ncgligible impedance between a line conductor and an exposed-conductive-pafi or a protective conductol' in the circuit or equipment within the disconnection tirne required i[ Regulation 4l I .3.2.3 or 4l L3.2.4 as appropriate.
I
704.414
Protective measure: Extra-low voltage provided by SELV or PELV
704.414.4 Requirements for SELV and PELV circuits rrns
704.414.4.5 Inespective ofthe rominalvoltage, inAC and DC circuits,
the requirement for basic protection shall
be provided by the foilowing:
(i) (ii)
basic insulation complyirg with Regulation 4[6.1. or barriers or enclosures complying with Regulation 416.2.
704.5
II
IS
,1
or
Selection and erection of equipment
704.51
Common rules
704.511
Compliance with standards
704.511.1 All
assemblies on constuuction and demolition sites for the distribution of electricity shall be in conpliance r,ith the requirements oIBS EN 61439-4.
A piug or socket-outlet with a rated current equal to or greater than 16 A shall comply with the requirements of BS EN 60309-2.
704.512
Operational conditions and external influences
I
704.5'12.2 External influences
I
Consideration shall be given to the risk of damage to electrical equipment by colTosive substances, movement of structLres and vehicles. wear and tear, tension, flexing, impact. abrasion, severing and ingress of Iiquids or solids.
:d
704.52
in
Wiring systems
704.522.8 Other mechanical stresses (AJ) 704.522.8.'10 Cable shall not be installed across a site road or a walkway unless adequate protection of the cable against n'rechanical damage is provided.
704.5?2.8.'l'l For reduced low voltage systems, low temperature
3 182/3/4/54 thermoplastic cable (BS 6004) or equivalent flexible cable shall be used. For applications exceeding reduced low voltage, llexible cable shall be H07RN-F (BS EN 50525-2-21) type or equivalent heavy duty flexible cable.
he the
I-
704.522.8.101 Surface-run and ovelhead cables shall be protected against mechanical damage, takirg into accoullt the environment and activitics ofa constructiol site.
[o*.n,
704.53 704.537 .2
t.-1.
Protection, isolation, switching, control and monitoring Devices for isolation
poltable Each Assembly tbr Construction Sites (ACS) shall incorporate suitable de\ ices tbr the su itching and isolation the incoming supply.
k t
-.-
of
fol securing in the offposition (see Regulali.ot 53T '2 4)' A ilevjce for isolaring rhe ir]coming supply shalt be suitable or by loiating the device inside a lockable enclosure for example, by p'ovidirg a padlo.r.i,ig iufity o" tl.,e device each ACS comprising: Cu:rent-using equiprnert sllall be supplied by ACSs, (i) overcurelt pl'otective devices, and
(ii) (iii)
dcvices atfolrling fault protection, and socket-outlets,
ifrequiled
of the means of devices aranged to prevent interconnectron Safety anrl staldby supplies shall be connected by difl'erent suPPlies
SECTION 705 AGRICULTU RAL AND HORTICU LTURAL PREMISES Scope
705.1
to fixed electrical jnstallations]*:T:1*::t*:t:.tl The pafiicular requircments of this sectiol applv are arso applicable
lf::*H:l
ffifl:I1:l,1ii.,iiffiiil:il;;*';;;;ii';';.' p':-i:::yl::".jl1.lii"'::[T:T::':,,1]:,""#''' ":1T11":::'.".:1111:'"11:::':Ti: lli,ffi:Tiffi'f i::il ;,,",n";;; ",ir,"''i,-.,r",*r text of the relevant regulations :J,"i.H:,ffi',:il:: l;;,;",?;;;;.-", r*1a-g, ,r-,i. is stated in the
'
and silnilar are not covercd by this section Rooms. locatiorN and areas for household applications BS EN 60335-2-76' NOTE: Sectior 705 cloes not cover electlic fence installations Referto
705.4'l
Protection against electric shock
705.410.3 Generalrequirements 705.410.3.5 The protective
(Section417) shallnotbeused' measures ofobstacles and placing out ofreach
705'4l0.3.6Theprotectlvenreasuresofnon-conductinglocation(Regulation4l8.l)andeafth-flgqlocal used' equipotential bording (Regulation 4I8'2) shall notbe
705.411
Protective measure: Automatic disconnection of supply
705.411.'l General Incircuits"whatevelthetypeofealthingsystem,thefollowingdisconnectiondevicesshallbeprovided: the with l.ated curent not exceeding 32 A' an RCD having
(i) ln final circuits
supplying socket-outlets characteristics specified in Regulation 415 1 1
(ii)Infinalcil.cuitssupplyingsockeGoutletswithratedcurrentlnorethan32A.anRCDwitharatedresidual
(iii)
opemting cunent flot exceeding 100 mA cunent not exceedilg 300 mA' In all othel circuits, RCDS with a rated residual opemting
705.411.4 TN system ATN'CsystemshallDotbeused'Thislequilementappliesalsotoresidencesandotherlocationsbelongingto of"Residences and other" premises" (see Part 2)' agricultural or horti.rlturul pr"n,i.", u."oJing to tt," o.nrition
To5.4l4Protectivemeasure:Extra.lowvoltageprovidedbySELVorPELV 705.4'14.4 Requirements for SELV and PELV circuits 705.414.4'SWhereSELVolPHLVisused'whateverthenominalvoltage'basicprotectiolshallbeprovidedby:
(i) (ii )
416' l' or basic irsulation complying with Regulation 4t 6 2 baniers or enclosures corr.tplying with Regulation
705.415.2.1 Additlonal proiection: Supplementary equipotential bonding
In
locations intended lbr livestock, supplementary bonding shall connect all exposed-conductive-parls ald extraneous-co[ductive-pafis that can be touched by livestock. Where a metal grid is laid in the floor, it shall be included within the supplementary bonding of the Iocation (Figure 705 shows an example of this, other suitable arrangements of a metal grid are not precluded). Extaneous-conductive-parts in, or on, the flooq e.g. concrete reinforcement in general or reinforcement of cellars for liquid manure. shall be connected to the supplementary equipotential bonding.
It is recomnrended that spaced floors made of prefabricated concrete elements be pafi of the supplementary equipotential bonding. The supplementary equipotential bonding and the metal gdd, if any, shall be erected so that it is dulably plotected against mechanical stresses and comosion. NOTE:
Unless a nretal grid is laid in the floor, the use of a PME earthing
lacility
as the means
of earthing for the electrical
installation is not recomrnended.
705.42
Protection against thermal effects
705.422
Measures for protection against fire
705.422.6
Electrical heating appliances used for the breeding and rearing of livestock shall comply with BS EN 60335-2 7l and shall be fixed so as to maintain an approp ate distance from livestock and combustible material, to mininize any risks of bums to livestock and of fire. For radiant heaters the clearance shall be not less than 0.5 rn or such other clearance as recommended by the manufacturer
705.422.7
For additional fire protection purposes in some circumstances, RCDs shall be installed with a rated residual operaling cunent not exceeding 300 mA. RCDs shall disconnect all live conductors. Where improved continuity ofservice is required, RCDs not protecting socket-outlets shall be olthe type S or have a time delay.
705.422.8
[n locations where a fire
isk
exists conductors of circuits supplied at extra-low voltage shall be ofIPXXD orIP4X or, in addition to their
protected either by baffiers or enclosures affording a degree ofprotection basic insulation, by an enclosure ofinsulating material.
NOTE:
For example. cables olthe lype H07RN-F (BS EN 50525-2-21) for outdoor use are in compliance with this requirement.
705.51
Selection and erection of equipment: Common rules
705.512
Operational conditions and external influences
705.512.2 External influences In agdcultural or l'rorticultural premises, electrical equipment shall have a minimum degree olprotection of 1P44. uhen used under normal conditions. Where equipment of IP44 rating is not available, it shall be placed in an enclosure complying with IP44. Socket-outlets shall be installed in
a
position where they are unlikely to come into contactwith combustible material.
Where therc are conditiors ofextemal influences >AD4, >AE3 and/or the appropriate p1 otection.
>AGl, socket-outlets shall be provided with
Protection may also be provided by the use ofadditional enclosures or by installation in building recesses. These requircments do not apply to residential locations, o{frces, shops and locations with similar extemal influences
belonging to agricultutal and horticultural premises where, for socket-outlets, BS 1363-2 or BS 546 applies.
\\'here coffosive substances are present. e.g. in dairies or cattle sheds, the electrical equipment shall be adequately protected.
705.513
Accessibility
705.513.2 Accessibilitybylivestock :lectrical equipmeut generally shall be inaccessible to livestock. Equipment that is unavoidably accessible to -ir estock such as equipment for feeding and basins for watering, shall be adequately constructed and installed to :.roid darragc by. and to minimize the sk ofinjury to, liyestock.
705.514
ldentification
705.514,9 Diagramsanddocumentation 705.514.9,3 The follo.*ing docurrentation shall be provided to the
(i) A plan irldicating the location of all electical (ii) The routing ofall concealed cables (iii) A silgle-1ine distribution diagram (iv) An equipotential bonding diaglam indicating
user ofthe installation:
equipment
locations ofbonding connections'
Selection and erection of equipment: Wiring systems
705.52
705's22Selectionanderectionofwiringsystemsinrelationtoexternalinfluences that they ue inaccessible to locations accessible to, and enclosing, livestock, wiring systens shall be erected so livestock or suitably protected against mechanical darlage
h
Overhead lines shall be insulated.
are operated, the following areas of agricultural premises where vehicles and mobile agricultural machines methods of installation shall be applied: (i) Cables shall be buried in the ground at a depth of at least 0.6 m with added mechanical ptotection
In
(ii) (iii)
Cables in arable or cultivaterl ground shall be buried at a depth ofat least 1 m Sclf-supporling suspcnsion cables shall be installed at a height ofat least 6 m
705.522.10
rodents. Special attention shall be given to the presence ofclifferent kinds offauna, e.g.
705.522.16 Conduit systems, cable trunking systems and cable ducting systems shall have plotection For locations wl]erc livestock is kept, extemal influences shall be classified AF4, and conduits according to outdools (high protection) 4 Class use and against corosion of at least Class 2 (mediurri) fot indoor BS EN 61386-21. due to vehicles and mobile For locations where the wirilg system n1ay be exposed to i[rpact and mechanical shock and: AG3 classifled be shall influences agricultural machines, ctc. the external
(i)conduitsshallpr.ovideadegreeolplotectionagainstimpactof5JaccordingtoBSEN6l386-21 (ii) cable tmnking and ducting systems shall provide a degree ofprotectior against impact of5 J according to BS EN 50085-2-
705.53
1.
Selection and erection of equipment: lsolation, switching and control
used' Only electrical heating appliances with visual irdication ofthe operating position shall be
705,537 705.537
.2
lsolation and switching lsolation
a single isolation device according The electlical installation ofeach building or part ofa buildil]g shall be isolated by to Chapter 46.
provided fbr circuits used Means of isolation of all live conductors, including the neutml conductof, shall be occasionally, e.g. during haryest time to which they belong' The isolatiol devices shall be clearly marked according to the parl ofthe installation
switching shall not be erected Devices for isolation and switching and devices for en.rergency stopping or emergency by livestock impeded may be access position whete where they are accessible to livestock or in any
705.54
Selection and erection of equipment: Earthing arrangements and protective conduGtors
705,544
Protectivebondingconductors 705.544.2 Supplementary bonding conductors
protective bonding conductors shal1 be protected against mechanical damage and corosion, and shall be selected to avoid electrolvtic eflects.
!+-
For exarnple, the lbllorving may be used:
1ii)
Hot-dip galvanized steel strip rvith dimensions ofat least 30 mm x 3 mm Hot-dip galvanized round steel ofat least 8 mm diameter
(iii)
Coppel conductor having a minimuln cross-sectional area of4 mm:
(i)
Otber suitable rnaterials may be used.
705.55
Selection and erection of equipment: Other equipment
705.553.1 Socket-outlets Socket-outlets of agricultural and horticultural premises shall comply with:
eIo
(i) (ii) (iii)
BS EN 60309-1, or BS EN 60309-2 where interchangeability is required, ot'
BS 1363 or BS 546 provided the rated current does not exceed 20 A'
705.56 , :.:
Safety services
705.560.6 Automatic life support for high density livestock rearing For high density Iivestock rearing, systems opemting for the life support oflivestock shall be taken into account as
iollorvs:
(i)
Where the supply of food, water, air and/or lighting to livestock is not provided in the event of power supply failuri, a secure source of supply shall be provided, such as an altemative or back-up supply final circuits shall be lsee also Section 551). For the supply of ventilation and lighting units separate ofthe ventilation the operation for necessary provided. Such circuits shall only supply electrical equipment and lighting
(
ii) Selectivity ofthe main circuits supplying the ventilation shall I
be provided in case ofany overcurrent and/ot'
shorl-circuit to Earth Where electrically powered venlilation is necessary in an instaltation one ofthe following shall be provided:
a)
A standby electrical source ensuring suflicient supply for ventilation equipment, or notice should be placed adjacent to the staodby electrical source, iidicating that pcliodically accotding to the manufacturcl's instructiotrs:
NOTE: A
b)
it
should be tested
temperature and supply voltage monitoring. This can be achieved by one or more monitoring devices The device(s) shall provide a visual or audible signal that can be readily observed by the user and shall opemte irdependently fi-om the nomlal supply.
ffiRrc'\ "; [**"
Fig 705
< X i o!
-
o:
Example of supplementary equipotential bonding within a cattle shed
o
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i
oatiEO.o FE E O l!-
i.
e
SECTION 706 CONDUCTING LOCATIONS WITH RESTRICTED MOVEMENT
706.1
Scope
The particular requirements ofthis section apply to:
(i) (ii)
fixed equipment in conducting locations whele novement of persons is restricted by the location, and to supplies for rnobile equipment for use in sucir locations.
A conducting location with restricted movement is comprised mainly of metallic or other conductive sunounding parts, within which it is likely that a person will come into contact thlough a substantial portion of the body u,ith the metallic or other conductive surounding parts and where the possibility of intempting this contact is limited. The particular requirements of this section do not apply to locations which allow a person freedo[r of bodily lnovement to work, enter and leave the location without physical constraint. For installation and use ofarc welding equipment, see IEC 60974-9. This section does not apply to elect cal systems as deflned in BS 7909 used in structures, sets, mobile units etc used for public or p vate events, toruing shows, theatdcal, radio, TV or'lilm productions and similar activities the entefi ainment industry.
706.4'l
as
of
Protection against electric shock
706.410.3.5 The protective
measures ofobstacles and placing or-rt ofreach (Section 417) shall not be used.
706.410.3.10In
a conducting Iocation rvith rest cted nlovement the following protective measures apply to circuits suppl) ine thc lollern ing current-rrsi g equiptnenr:
(i)
For the supply to a hand-held tool or an item
oflrobile equipmert:
(a) electrical separatior (Section 413), subject to only one item ofequipment being connected to a secondary winding ofthe tran sfonner, or NOTE: The transformer may have trvo or more secondary windings.
(b) SELV
tii)
(SectioD 414).
Fol thc srrppll ro lrandlamps:
(a) SELV (Section 414). It is permissible lor the SELV circuit to supply a fluorescent lurninaile with
a
built-in step-up traoslormcr with electrically separated windings.
(iii)
For the supply to fixed equipment:
(a) automatic disconnection of supply (Section 4ll) with supplementary protective equipotential bonding (Regulation 415.2). The supplemettary protectiye equipotential bonding shall connect exposed-conductiYe-parts olflxed equipment and the conductive
pa s ofthe location, or
(b) by use of Class II equipment or equipment having equivalent insulation (Section 412), provided the supply circuits have additional protection by the use of RCDs having the chamcteristics specified in Regulation 4l5.l .l, or
(c) electrical sepamtion (Section 413), subject to only one item ofequipment being connected to a secondary winding of the isolating transfomer, or
(d) SELV (Section 414), or (e) PELV (Section 414), where supplementary protective equipotential bonding is provided benr een all exposed-conductive-paI1s, al1 extraneous-conductive-parts inside the location, and the connection ofthe PELV system to Eafth.
F t
.-,,
'
2Et
706.4'11
Protective measure: Automatic disconnection of supply
706.411.1 General 70g,4'11.1.1
Only circuits and the protective neasures for supplying equipnent iltdicated
Regulation 706.410.3.
t
in
0 are pemitted.
is required for certain equipment, for example measuring and control equipment. and supplementary protective equipotential bonding shall be provided between all exposed-conductive-pafis
706.411.1.2 Ifa functional eath
extraneous-conductive-parts irlside the locatiolt and the functional earth.
706.413
Protectivemeasure:Electricalseparation
706.413.,1.2 The uneafihed source shall have simple separation and shall be situated outside the conducting
provided location witlt restricted movement. unless the source is part ofthe fixed installation within the locatiot as 10. by item(iii) of Regulation 706.410.3.
706,414
Protective measure: Extra-low voltage provided by SELV or PELV
706,414.3 Sources for SELV and PELV 706.414.3(ii) A source for SELV or PELV shall be situated outside the conducting location with restricted (iii) of movemelt, unless it is part of the fixed installation within the location as provided by item Regulation 706.41 0.3. 10.
706.414.4 Requirements for SELV and PELV circuits 706.414.4-5 Where SELV or pELV
(i) (ii)
264
is used, whateve[ the nominal vottage, basic protection shall be provided by:
basic insulation complying with Regu)ation 416.1, or barriels or enclosures cott'tplying with Regulation 416.2
SECTION 708
ELECTRICAL INSTALLATIONS IN CARAVAN / CAMPING PARKS AND SIMILAR LOCATIONS NoTE:
In order not to D x requircments ou diffcrent subjects, such as thosc lor electrical installations ofcaravan parks with those for elcctrical installations inside caravans, rel.er to: Section 708- which concems electrical installations in caravan parks. camping par.ks and sil.Iri]ar locations and Section 721. which conccrns cleciicalinstallations in caravans and rrotor carar.ans
-
708.1 I he .
Scope
particular tequiiements contaired in this section apply orrly to circuits intended to supply leisure acconrrnodation
ihicles. tents or residential park homes in caravan parks, camping parks and similar locations.
This sectiol1 does not apply to the intel]ral electrical installations of leisure accommodatiou vehicles or mobile or :rlnsportable units. NOTE 1: For installatiolls in caravans cnd lrotor caravans which are operated at l2
NoTE 2: Fo. installatiols in catavans
v
DC. BS EN l64g-l and 2 apply.
and ntotor camvans which are opemted at voltages other than
NoTE 3: Thc electrical installations of lcsidcntial
l2
v
DC. section 721 applies.
par-k homes are covercd by the gencml rcqlrireme1is
with the r.clcvant pafticular requirements ofpart
ofBS 7671, togcther
7.
708.3 A,ssessment of general characteristics 708.3't Purposes, supplies and structure 708.312
Conductor arrangement and system earthing
708.3'12.2 Types of system earthing
708.313
Suppties
ne nominal suppll' voltage of the installation tbr the supply of leisure accommodation vehicles shall not exceed i-r0 V AC single-phase or 400 VAC thr.ec-phase or 4g V DC
708.4 708.41
Protection for safety Protection against electric shock
708.410.3 Generalrequirements 708 4'10'3
5
The protective measures ofobstacles andplacirg out ofreach (Section417) shall not be r.rsed.
708410.3.6 The protective measutes of non-conducting locatiorl (Regulation 418.1) and eafih-fl.ee local :;uipetential bonding (Reg'ulation 418.2) shall not be used.
708.411.4 TN system r:' Electricity Sat'ety' Quality and Continuity Regulations (ESQCR) prohibit the cornection of a pME earthiflg
::Jilit), to any metalwork in a leisure acconmodation vehicle (includini - ris cloes not preclude the use ofa PME eafthing facility r-lallations of pe nanent buildings.
NOTE:
The requir.entents ofother sections
ofpaft
as the means
7 may also apply.
a caravan;.
ofeafthing for other purposes, such
as to the
I I
I I
708.415
Additionalprotection 708.415.1 Residual current protective devices (RCDS) Eyery socket-outlet shall be individually protected by anRCD having 30 mA. Devices selected shall disconnect all live conductol's.
a
ratedresidual opemting current not exceeding
A final circuit intended for the fixed connection of a supply to a mobile home or a residential park home shall be individually protected by an RCD having a rated residual operating curent not exceeding 30 mA accessible to the consutler. Devices selected shall disconnect all live conductors.
NOTE:
This finai circuit will be liom the coDnection/mctering point to the consuner and not the distribution circuit to the connection/rnetering point.
708.5
Selection and erection of equipment
708.512
Operational conditions and external influences
708.512.1.1 Presence of water (AD) EquipDrent shall be selecteil with a degree of protection of at least IPX4
ill order to protect against water
splashes
(AD4).
708.512.1.2 Presence of solid foreign bodies (AE) Equipmerrt shall be selected or provided with a degree of protection of at least lP4X in order to protect against the ingress of very small obJects (AE3).
708.512.2 External influences
NOTE:
par* or camping park, special consideration is given to the protection ofpeople, duc to the fact that the human body nray be i[ contact with earth potential, to the protection of wiring due to tent pegs or ground anchors and to the novement ofheavy or high vehicles.
Ir
a camvan
708.512.2.'1.3 lmpact (AG) Equipment installed in a campsite shall be protected against mechanical {amage (impact of high severity AG3). Prorection ofthe equipment shall be afforded by one or more ofthe following:
-
the position or locatiol] shall be selected to avoid damage by any reasonably foreseeable impact
Iocal or gcneral mechanical protection shall be provided equipment shall be imtalled that complies with a minimum degree ofprotection against extemal tlechanical iupact of IK08 (see BS EN 62262).
708.521
Types of wiring system
708.521.7 Wiring systems in caravan parks 708.521.7.1 The pr.eferred method of supply for feeding the caravan pitch or tent pitch electdcal supply equiptnenr is by means of underground distribution circuits. 708.521.7 .2 Underground cables
An underground distribution circuit shall, unless provided with additional mechanical protection, be buried at
a
sufficieut depth to avoid being da[raged, e.g. by tent pegs or ground anchors or by the movement ofvehicles. NOTE 1: A clepth of 0.6 rn is generally corsidered as
a
minimum depth to f'ulfilthis requirement. Altematively, the cable oay
be installed outside the pitch or other area \\'hele tent pegs or ground anchors may be dtiven.
NOTE 2: For conduit systenN buried underglound, sec BS EN 61386-2'1.
708.52'1.7.3 Overhead cables and overhead insulated conductors Every overhead conductor shall be insulated. Poles and other supports for overhead wiring shall be located or protected so that they arc unlikely to be da[raged by any loreseeable movenent ofvehicles. Every overheatl conductor shall be at a height above ground ofnot less than 6 m in all areas subject to the movement ofvehicles and 3.5 m in all other areas.
266
T 708.53 708.533
Protection, isolation, switching, control and monitoring Devices for protection against overcurrent
Every sochet-outlct shall be individually protected by an overcrLrent protective device, in accotdance requirements olChapter 43.
\: '
A fixed connection for a supply to a mobile home or residential park home shall be individually protected b) overcurrent protective device, in accordance with the requirements ofChapter 43
708.537
-
.
=
lsolation and switching
708"537.2 lsolation 708.537
.2.1
General
708.537.2,1.1 At
least one means ofisolation shall be installed in each distribution enclosure. This device shall
disconnect all live conductot's.
708.55 r;hes
Other equipment
708.55.1 Socket-outlets 708.55.1.1
-
Every socket-outlet or cotnector shall cithet comply with:
BS EN 60309-2 and shall be interlocked and classified to clause 6.1.5 of BS EN 60309-1 to prevent the socket contacts being live when accessible, ot'
.:i the
-
be pafi of an interlocked self-contained product complying witb BS EN 60309-4 and classified to clauses 6.l.l0l and 6.1.102 of BS EN 60309-4 to prevent the socket cortacts being live when accessible.
Caravan pitch electrical supply equipment shall be located adjacent to the pitch and not more than 20 il.i from the connection facility on the Ieisure accommodation vehicle or tent when on its pitch.
708.55.1.2 acr that d 10 the
In order to avoid any hazard due to long connection cables, no more than 4 socket-outlets shall be !.rouped togcther in any one enclosule.
708.55.1.3
708.55.'1.4 Every caravan pitch
; \Gi).
rhanical
708.55.1.5
or tent pitch shall be supplied by at least one socket-outlet'
The curent rating of socket-outlets shall bc not less than l6 A.
708.55.1 .6 The lowest paft of any socket-outlet shall be placed at a height between 0.5 m and 1.5 m from the the stated maximum height .rou1d. In special cases of extrene environmental conditions, it is pemitted to exceed olplugs withdrawal and safe insertion to allow the taken measrLres shall be ln such cases, special :.a 1.5 rr.,.
NOTE: Thiscanbelecessaryifthecaravanparkorcampingparkisat
sk
ofbeingflooded or ifeither location is used during
winter after hea\,y snow falls.
Switchgear and controlgear assemblies used in caravan/tent pitch supplies shall comply with the ::quirements ofBS EN 61439-7.
708.55.1.7 :i -:ipl-I1enl
708.553.'l Plugsandsocket-outlets 708.553.1.8 Each socket-outlet and its enclosure loming part olthe caravan pitch electdcal supply equiprnent .:r)l comply with BS EN 60309-2 and meet the degree ol protection of at least IP44 in accordance with
ls
708.553.1.14 Socket-outlet protective conducto$ shall not be cornected to cable tnal
datraged
mo\ emeni
I
EN 60529. a
PME earthing facility.
I
Fig 708
-
Example of a 2-pole and protective conductor supply system between the caravan pitch supply equipment and the caravan or motor caravan
NOTE: S.. atroR.!.r -: r -:1.5-':.(,
Site supolv Sockeroulet
L.e .ondu.lor
Neutra condrcror
1us
qr..r1
rr1
ff
(N)
Blue Neulral
coidldor (N)
s
L1)
L1)
Vew.i
View ofcont cttubes
conductor(N)
(e.0.
L1)
p
ns
Vlew ol term na s
Line Bown Line Blue conductor conductor Neutra
Brown Line
conduclor {e q. L])
(e.s.
@/
@/
Vewoltermnals
(e
(N)
(N)
(e.!
L1)
(e
s
Ll)
coiduclor (N)
/oo\ v)a) \:.,/-/
-<E (e)
Ht_
\olf )tl
Connection devlce
Caravan inlet
NOTE 1: Sec Rcgulation 708.55.1.1 for interlocking requirements. NOTE 2: Typical requilements for cable extension sets.
268
l--_---
The ureans ofconnection between the caravan pitch socket-outlet and the leisure acconrmodation vehicle shouid r.an assernbly ofthe follou.ing:
-
a plug corrplying with BS EN 60309-2
a flexiblc cable type to H05RN-F or H07RN-F (BS EN 50525-2-21) or equivalent. wirh a plotecri\e conductor and having the following characteristics:
-
continuous length 25 rn (t2 m)
for cu[ent rating l6,4. minimum cross-sectional area: 2.5 mm2. For a higher curuent rating, the crosssectional area must be chosen so that secure t pping ofthe overcurent protective device is achieved at the lowest fault current calculated at the end ofthe cable extensiotr set
-
conductors to be identified in accordance with Table 51
a connector
.L.-
courplying with BS EN 60309-2.
269
SECTION 709 MARINAS AND SIMILAR LOCATIONS
709.1
Scope
pleasure craft or The parlicu)ar requirenerts of this section are applicable only to circuits intended to supply houseboats in tnarinas and similar locations. NOTE 1: In this section 'marina' means 'marina and sitnilar locations'
The particular requirements do rot apply to the supply to houseboats network.
if they are supplied directly lrom
the public
ofpleasure craft oI houseboats' The particular requiremerts do not apply to the intemal electrical installatiots NOTE 2: For elcctrical installatiolls olpleasure cmft see BS EN 60092-507' requirements ofthese Regulations together The electrical installations ofhouseboats shall cornply with the general 7. with the relevant particular requirements ofPart
of these For the renainder ol the electrical installation of n.nrinas and similar locations the general requirements Regulatiors together with the rclevant particular requirements of Part 7 apply'
Assessment of general characteristics
709.3
709.313
Supplies
houseboats shall 709.313.1.2 The nominal supply voltage ofthe itstallation fot the supply to pleasure craft ot
be
230 V AC single-phase or 400 V AC three-phase.
709.41
Protection against electric shock
709.410.3 Generalrequirements 709.410.3.5 Thc protective
used' measures ot obstacles and placing out ofreach (sectioo 417) shall not be
arrd earth-free local 709.4,t0.3.6 The protectivc rrreasures of non-conductilg location (Regulation 418.1) equipotential bonding (Rcgulation 418.2) shall not be used'
709.411.4 TN system the connection of a PME earthing The Elcctricity Safcty, Quality and Continuity Regulations (ESQCR) prohibit facility to any metalwork in a boat
foI other purposes, such as to the This does 1.Iot preclucle the use ofa PME earlhing facility as the means ofeafihing inslallationq oI pem ranent bttildirlgs
NOTE:
The requirements ofother secfions ofPart
709.5 70g.512
7
ay also apply'
Selection and erection of equipment Operational conditions and external influences
709.512.2 External influences this section to the likelihood of corrosive elements. movement of of flammable fuel and the increased risk olelectric shock due to:
For marinas, particular attelltion is given structures, mechanical damage, presence
(i) (ii) (iii)
i[
presence of water
r'eduction in body resistance contact ofthc body rvith Earth potential.
709.5'12.2.1,1 Presence of water (AD) be selected ln maritas, equipment installed on or above ajetty' whad, pier or pontoon shall the extemal influences which may be present:
1i1 Water:plashcs lAD4l: lPX4
(ii) (iii)
water jets (AD5); IPX5 Water waves (AD6): IPX6
as
follows' according to
709.512.2.1.2 Presence of solid foreign bodies (AE) Equipment installed on ol abovc a jetty. rvharf, pier or pontoon shall be selected with a degree ol protection oi ar least IP3X in order to protect against the ingress of small objects (AEZ).
709.512.2.1.3 Presence of corrosive or polluting substances (AF) Equipment installed on or above ajetty, wharf, pier or pontoon sl'nll be suitable for use in the presence ofatmospheric corosive or polluting substances (AF2). lfhydrocarbons are presert, AF3 is appticable. 7
09.5'12.2.'1.4 lmpact (AG)
Equipment installed on or above a jetty, wharf, pier or pontoon shall be protected against mechanical damage (impact of r.[ediurl sevefityAG2). Protection shall be afforded by one or more oftlre following: (i) The position or location selected to avoid being dan.raged by any reasonably foreseeable impact
(ii) (iii)
::.I
The provision oflocal or general mechanical protection
Installitg equipment complying with
a
minimum degree ofprotection for external mechanical impact IK08
(see BS EN 62262).
709.521
Types of wiring system
709.52'1.'l Wiring systems of marinas 709.52'1.1.4 The following wiring
systems are suitable for distribution circuits ofmarinas:
(i) (ii) (iii)
Undcrground cables
(iv) (v) (vi)
Mineral-insulated cables with a PVC prolective covering
Overhead cables or overhead insulated conductots Cablcs with copper conductors and thennoplastic or elastomeric insulation and sheath installed within an appropdate cable management system taking into account extemal influences such as movement, impact, conosion and ambient temperature Cables wittr armouring and serving of thermoplastic or elastomedc matedal Other cables and materjals that are no less suitable than those listed above.
709.521.1.5 The following wiring systems shall not be used onol above a jetty, wharf, pier or pontoon:
(i) (ii) (iii) (iv)
:ling :n the
Cables in free air suspended from or incorporating a support wire, e.g. as installation methods Nos. 35 and 36 in Table 4A2 Non-sheathed cables in cable management systems Cables with aluminium conductors
Mineral insulated cables. tidal and other movement
of
Cable managerrent systems shall be installed to allow the drainage ofwater by drainage holes and/or installation the equipment on an incline.
of
709.521.1.6 Cables shall be selected ard installed
so that mechanical damage due to
floating structures is prevented.
709.521,1.7 Underground cables Underground distribution cables shall, unless provided with additional mechanical protection, be buried at a sufEcient depth to avoid being damaged, e.g. by heavy vehicle movement.
oent of
NOTE:
A depth of0.5 m is generally considered as a minimum depth to
frlfil
this requirement.
709.521.1.8 Overhead cables or overhead insulated conductors
All overhead conductors shall be insulated. Poles and other suppofls for overhead wiring shall be located or protected so that they are unlikely to be damaged by any foreseeable vehicle movement.
:r-'-:rIg to
Overhead conductors shall be at and 3.5 rn i[ all other areas.
h
i
--iE-
a
height above ground ofnot less than 6 m in all areas subjected to vehicle movement
271
709.531
Devices for fault protection by automatic disconnection of supply
709.531.2 RCDs Socket-outlets shall be protected individually by an RCD having the characteristics specified in Regulation 415.1.1. Devices selected shall disconnect all poles, including the neutml.
Final cilcuits illtended 1br fixed connection for the suppiy to houseboats shall be protected individtnlly by an RCD having the characteristics specified in Regulation 415.1 .1. The device selected shall disconnect all poLes, including the neutral.
709.533
Devices for protection against overcurrent
Each socket-outlet shall be protected by an individual overcurrent protective device, in accordance with the requirements olChapter 43. A fixed comection for supply to each houseboat shall be protected individually by an overcunent protective de\,ice, in accordance with the requirements ofChapter 43.
709.537
lsolation and switching
709.537.2 lsolation 709.537.2.1 General 709.537 .2.'l '1 At least one means of isolation shall be installed in each distribution cabinet. This switching device shall disconnect all live conductors including the neutal conductol'. One isolating switching device for a maximum offour socket-outlets shall be irrstalled.
709.55
Other equipment
709,553.1 Plugsandsocket-outlets 709.553.1.8 socket-outlets shall comply with BS EN 60309-l above 63 A and BS EN 60309-2 up to 63 A. Every socket-outlet shall meet the degree of prctection of at least IP44 or such protecriol'r shall be provided by an enclosure. Where the codes AD5 orAD6 are applicable the degree ofprotection shall be at Ieasr either lPX 5 or lPXo respectively.
709.553'1.9 Every socket-outlet shall be located
as close as
practicable to the berth to be supplierl.
Socket-outlets shall be instatled in the distdbution board or irl separate enclosures.
709.553.1.10 In order to avoid any hazard due to long cornection cords, a maximum offour socket-outlets
sha11
be
grouped together in one enclosure.
NOTE:
Sce Fjgure 709.3 rcgarding the recommended illstruction notice to be placed
in marinas adjacent to cach group of
socket-outlets-
709.553.1.11 One socket-outlet shall supply only one pleasure cralt or houseboat.
709.553.1.12In general, single-phase socket-outlets with
raterl voltage 200
V
250 V and rated cunent
l6Ashall
be provided.
where greatcr demands are envisaged socket-outlets with higher current ratings shall be provided. 709.553.1 .1 3 Socket-outlets shall be pJaced at a height of not less than I m above the highest water 1evel. In the case of floating pontoolls or walkways only, this height may be reduced to 300 mm above the highest water level provided that appropriate additional measures are taken to protect against the effects of splashing.
272
[--
to a P\lE eafthing facility' 709.553.1 .14 Sockct-outlet protecti\ e condtictors shall not bc connected
in marinas Figs 709.1 & 2 - Examples of methods of obtaining supply Fig 709.'l
-
Connection to a single-phase mains supply with RGD rl
Swltch
R;sidual current device
\ L N
PE
To metal parts n electrical contact with water surrounding
he pleasure craft
Fig 709.2 t1:19
.:
a
-
Connection to a three-phase mains supply with RCD
I\rain switch
\ L1
L2 L3 N
rl
-\.
:) all To metal pads ln electrical contacl wilh water surrounding
..-t. PE
hail be
Soup
of
Fig 709.3
-
Example of an instruction notice to be placed in marinas
pleasure craft operator who wishes to connecl a pleasure NoTE 1: It is recommended that the narina operator provides every notice' cmft to an electrical supply with an up{o date copy ofthis instruction
NOTE 2: The instruction notice should contain' at
,t
1east, the
following:
sirall
ln the level
6.*'",%
5""r,"*
"A
zBl
INSTRUCTIONS FOR ELECTRICITY SUPPLY BERTHING INSTRUCTIONS FOR CONNECTION TO SHORE SUPPLY This marina provides power for use on your pleasure craft with a direct connection to the shore supply which is connected to Earth. Unless you have an isolating transformer
fitted on board to isolate the electrical system on your craft from the shore supply system, corrosion through electrolysis could damage your craft or surrounding craft. ON ARRIVAL
(i)
(ii) (iii) (iv) (v) (vi) (vii) (viii)
Ensure the supply is switched off and disconnect all current-using equipment
on the craft, before inserting the craft plug. Connect the flexible cable the pleasure-craft inlet socket and then at the marina socket-outlet.
* The supply at this berth is * V, Hz. The socket-outlet will accommodate a * standard marina plug colour (technically described as BS EN 60309-2, position 6 h).
For safety reasons, your craft must not be connected to any other socketoutlet than that allocated to you and the internal wiring on your craft must comply with the appropriate standards. Every effort must be made to prevent the connecting flexible cable from falling into the water if it should become disengaged. For this purpose, securing hooks are provided alongside socket-outlets for anchorage at a loop of tie cord
For safety reasons, only one pleasure-craft connecting cable supplying one pleasure craft may be connected to any one socket-outlet. The connecting flexible cable must be in one length, without signs of damage, and not contain joints or other means to increase its length. The entry of moisture and salt into the pleasure-craft inlet socket may cause a
hazard. Examine carefully and clean the plug and socket before connecting the supply. lt is dangerous to attempt repairs or alterations. lf any difficulty arises, contact the marina management.
BEFORE LEAVING
(i)
(ii)
Ensure that the supply is switched off and disconnect all current-using equipment on the craft, before the connecting cable is disconnected and any tie cord loops are unhooked. The connecting flexible cable should be disconnected firstly from the marina sockefoutlet and then from the pleasure-crafl inlet socket. Any cover that may be provided to protect the inlet from weather should be securely replaced. The connecting flexible cable should be coiled up and stored in a dry location where it will not be da
* appropriate figures and colours to be inseded: nominally 230 V 50 Hz blue - single-phase, and nominally 400 V 50 Hz red - three-phase.
274
firstly at
SECTION 710
MEDICAL LOCATIONS Scope
710.1
The parlicular requirements of this section apply to patient healthcare facilities, such as, hospitals, private clinics. medical and dental practices, healthcare centres and dedicated medical rooms in the workplace to provide 1br the safety ofpatients and medical staff.
In these areas the risk to patients is increased due to: the reduction in body resistance, since the skin is often cut or broken, and
the threat ftom failure ofthe supply, especially to life suppofiing equipment.
This section also applies to electrical installations in Iocations designed for medical research on patients. The requirements ofthis section do not apply to medical electrical (ME) equipment. NOTE 1: The requirenents of other sections ofParl 7 may also apply. NOTE 2: It may be necessary to modify the existing elect cal installation, in accordance with this Standard, when a change of utilization ofthe location occurs. Special carc should be taken where intracardiac and/or life supporting procedures are perfonned in existirlg imtallations. NOTE 3: Where appJicable, this Standard can also be used in veterinary clinics. NOTE 4: for ME equipment and ME systems, refer to the BS EN 60601 sedes. NOTE 5: Care should be taken
so that other
installations do not compromise the level of safety provided by installations meeting
the requirements of this section.
NOTE 6: Supporting information about elect cal services supply and distribution in healthcare premise is given in Health Technical Memorandum (HTM) 06-01, published by the Department ofHealth.
7'10.3
I I
Assessment of general characteristics
ln order to determine the classification and Group number of a medical location, it is necessary that the relevant medical stalfindicate which medical procedures will take place within the location. Based on the intended use, the appropriate classification for the location shall be determined. NOTE 'l: Classification of a medical location is related to the type of contact between applied parts and the patient, the threat to the safety ofthe patient owirg to a discontinuity (failure) ofthe electrical supply, as well as the purpose for which the locatiorl is used. (Guidance on the allocation of a Group number and classification of safety services for medical locations is shown in Annex A710.)
NOTE 2: To provide protection of patients from possible electrical hazards, additional protective measures are applied in medical locations. The type and description ofthese hazards can vary according to the treatme[t being adminislered. The purpose for which a location is to be used may justify areas with different classifications (Group 0, I or 2) for diffelent medical procedures.
NOTE 3: Applied parts are def,ned by the particular standards for ME equipment. NOTE 4: Where a medical location may be used for diffelent medical procedures the requirements of the higher Group classification should be applied: refer to Annex A710.
710.3'l
Purposes, supplies and structure
710.312.2 Types of system earthing PEN conductors shal1 not be used in medical locations and medical buildings downsteam ofthe main distribution board.
NOTE: 71 0.31
Regulation 8(4) of the Electricity Safety, Quality and Continuity Regulations (ESQCR) prohibits the use of PEN conductors in consumers' installations.
3
710.313.1
Supplies General
-n medical locatiors, the distdbution system shall be designed and installed to facilitate the automatic changeoler :ion1 the main distdbution network to the electrical safety source feeding essential loads, as required b1
Regulation 560.5.
i V
-*--
275
7',to.4
Protection for safety
710.41
Protection against electric shock
710.410.3 General requirements 71 0.41
0.3.5
710.410.3.6
The protective neasures ol obstacles and placing out of reach (Section 417) shall not be used. The protective measures ofnon-conducting location (Regulation 418.1), eafih-tiee local equipotential
bording (Regulation 418.2) and electrical separation for the supply to more than one item ofcurent-using equipment ( Regulation 4l R.l ) 5hall nor be Lr.ed.
NOTE:
A rnedical lT system does nol use electrical separation as the sole rneans ofprotection against elecrric shock.
710.411.3 Requirements for fault protection 710,411.3.2 Automatic disconnection in case of a fault
710,411.3.2.1
Care shall be taken so that simultaneous use ofmany items olequipment corrected to the same circuit cannot cause unwanted trjpping ofthe residual cun'ent protective device (RCD).
In medical locations ofGloup I and Group 2, where RCDs are required, only Type A according to BS EN 61008 aud BS EN 61009 or Type B according to BS EN 62423 shall be selected, depending on the possible fault curent arising. Type AC RCDs shall lot be used.
I I
710.411.3.2.5 In medical locations of Group I and Group 2, the voltage
presented betlveen simultaneously accessible exposed-conductive-pafts and/or extlaneous-conductive-parts shall l1ot exceed 25 V AC or 60 V DC.
710.411.4 TN system
I
Additional protection by RCDs having the chamcteristics specified in Regulation 4l5.l.l shall be used: (i) in final circuits ofGroup I with rated curent not exceeding 32 A and below, and
(ii)
in final circuits of Group 2, except those of the medical IT system specified in Regulation 710.411.6.
NOTE:
It is also permissible to
Lrse
RCDs above 32 A in Group I locations.
710.411.5 TT system In medical locations ofGroup I and Group 2, RCDs shall be used as protective devices, except for circuits ofan IT system specified in Regulatioo 710.41L6.
710.41'1.6 lT system In Group 2 medical locations ofan lT system, including the measures ofRegulation 710.411.6.3.1, 710.411.6.3.2 and 710.512.1.1, shall be used for final circuits of ME equipment and ME systems intended for lile support and surgical applications within the patient environnent, excluding:
(i) (ii) (iii)
equipment with a rated power greater than skVA
X-ray equipment the supply ofmovements offixed operating tables.
For each group ofrooms serying the same function, at least one medical IT system is necessary. NOTE 1: The list of circuits in (i) to (iii) above is not exhausrive. NOTE 2: For illustration of
a
typical theatue layout refel to Figure 710.2.
NOTE 3: A systen constructed to the requiremeDts ofReglrlation 710.41 1.6 js known as a medical IT system.
710,411.6.3.1 For each group ofrooms serving the same function, at least one medical IT system is necessary. The IT systerr shall be equipped with an insulation monitoring device (MEDJMD) in accordance with Annex A and Annex B ofBS EN 61557-8. For each medical IT system. an audible and visual alam systen, incorporating the lollowing components, shall be provided so that
(i) (ii)
it
can bc pennanently rronitored by the medical staffand any alarm reported to technical staff:
A green signal lamp to indicate nonnal operatiou
A yellow signal laurp ri hich lights when the minimum value set for the insulation resistance is reached. [t shalJ not be possib)e lor this light to be cancelled or djsconnected
(iii)
An audible alarm rvhich sounds when the minimum value
(iv)
The yellow signal shall extinguish on removal ofthe fault and when the normal condition is restored.
set for the insulation resistance is reached.
Th:.
audible alann may be silenced
Documentation shall be easily readable in the medical location and it shall include:
iial ent
(v) (vi)
the meaning ofeach type ofsignal, and the procedure to be followed in case of an alam at first fault.
710.411.6.3.2 Monitoring ofoverload
and high temperature for the IT tmnsformer is required.
7'10.411.6.3.3 In addition to an insulation monitoring device, consideration shall be given to the installation of fault location systems which localize insulation faults in any pafi ofthe medical lT system The insulation lault location system shall be in accordance with BS EN 61557-9.
710,4'11.7 Functional extra-low voltage (FELV) ame
In medical locations, functional extra-low voltage (FELV) shall not be used as a method of protection against electric shock-
1008
rent
710.414
Protective measure: Extra-low voltage provided by SELV or PELV
710.414.1 General lusly
When using SELV and/or PELV circuits in medical locations ofGroup I and Group 2, the nominal voltage applied to current-using equipment shall not exceed 25 V AC rms or 60 V ripple-free DC. Protection by basic insulation of live parls as required by Regulation 416. I or by barriers or enclosures as required by Regulation 416.2. sh all he provided.
710.414.4.1 In medical locations of Group 2, where PELV is used, exposed-conductive-pafis of equipment. e.g. operating theatre luminaires, shall be connected to the circuit protective conductor
710.415.1 Additional protection: RCDs Where a medical IT system is used, additional protection by means ofan RCD is not required.
710.415.2 Additional protection: Supplementary protective equipotential bonding lan IT
t.6.3.2
on and
each medical location ofGroup 1 and Group 2, supplementary protective equipotential bonding installed and the supplementary bonding conductors shall be connected to the equipotential bonding busbar shall be potential differences between the following par1s, which are located or that ma) be purpose of equalizing for the moved into the 'patient environment':
710.4'15.2.'l ln
(i) (ii) (iii) (iv) (v)
Protectiveconductors Extraneous-conductive-parts Screening against electrical interference fields, ifinstalled Connection to conductive floor grids,
il installed
Metal screens of isolating tuansfonners, via the shoftest route to the earthing conductor
Supplementary equipotentiat bonding connection points for the connection of ME equipment shall be available in Group 2 and should also be considered in Group I medical locations. The designerin consultation with the end user shall determine the appropriate number ofsupplementary equipotential
bonding connections. :,.'iSary.
::::1e\ A
NOTE 1: In a Group I medical location, a minimum of one supplementary equipotential bonding connection point per prtieni location is recommended. In a Group 2 nedical location, a mininurn number of four supplernentary equipotential bonding conncction points but not less than 25 o/o ofthe total number ofindividual medical IT socket-outlets plovided per patient location is recomrnended.
.. :hall
-., .tatf: :.,: ',ed lt
NOTE 2: Manufacturers of fixed conductive non electdcal patient supports such as operating theatre tables, physiotherapl couches and dental chaiN may require the equipment to be connected to the equipotential bonding conductor.
710.415.2.2 ln medical locations of Group 1 and Group 2, the resistance of the protective conductors betNeen the earth teminal of any socket-outlet (or fixed equipment) and any exposed-conductive-pafi and/or extraneousconductive-part shall be such that the voltages given in 710.41 1.3.2.5 are not exceeded. and the measured resistance between the eafih terminal of any socket-outlet (or fixed equipment) and any e\tral]eous-conductive-part shall noi exceed 0.2 C).
obtained by the provision of protective protective conductors for the particular circuit. In the case of equipotential bondlng in conjunction with circuit be required TT systems a satisfactory value ofRe will also
NOTE: In TN and TT sysrems. a lalue of 25 V AC or 60 V DC may be
710.415.2.3 The equipotential bonding busbar shall
be located in or near the medical location.
The equipotential bonding busbar sha1l be connected to the system eafihing using a protective conductor having a cross-sectional area greater than or equal to the largest cross-sectional area of any conductor connected to the equipotential bonding busbat. Connections shall be so aranged that they are accessible, labelled, clearly visible and can be individually disconnected.
NOTE: It is recomnrended that radial wiring patterns are used to avoid 'earth loops' that
may exacerbate electromagnetic
disturbances.
710.421.1.201 ln medical locations of Group I and 2 Arc Fault Detection Devices (AFDDs)
are not rcquired to
be installed. In medical locations of Group 0 Arc Fault Detection Devices (AFDDs) shall be used subject to
a
risk
assessment.
710,444
Measures againstelectromagnetic disturbances
Special considerations have compatibility (EMC).
710.5
to be made conceming elecfomagnetic
interference (EMI) and electomagnetic
Selection and erection of equipment
7'10.51
Common rules
710.511.1 Distribution boards Distribution boards shall meet the requirements ofBS EN 61439 series. Distribution boards for Group 2 locations shall be installed in close proximity to the
areas
they serve and be clearly
labelled.
710.512
Operational conditions and external influences
710.512.1 Operational conditions 7'10.512.1.1 Transformers for medical lT systems Transfonners shall be in accordance with BS EN 61558-2-15, installed in close proximity to the medical location and with the lollowing additional requirements;
(i) (ii)
The leakage current ofthe output winding to earth and the leakage current ofthe enclosure, when measured in no-load condition and with the tmnsformer supplied at rated voltage and rated frequency, shall not exceed 0.5 mA At least ofle single-phase transformer per room or functional group of rooms shall be used to form the nedical IT sysrems lor nlobile and fixed equipment. The rated output shall be not less than 0 5 kVA and shall not excced 10 kVA. Where several transformers are needed to supply equipment in one room, they shall not be connected in parallel
(iii) Ifthe supply ofthree-phase
loads via a medicat IT system is also required, a separate three-phase tmrslormer
shall be provided for this purpose. For monitodng see Rcgulation 710.41 1.6.3.1. Capacitors shall not be used in tmltsfolmers for medical IT systems.
710.512.1
ln case of
NOTE:
.2 a
Power supply for medical locations of Group 2
fault or a failur e of supply,
a
total loss of power in a Group 2 medical location sha[1 be prevented
Suppoltirg infomration is given in HTM 06-01
710.512.2.1 Explosionrisk Electrical devices, e.g. socket-outlets and switches, installed below any medical-gas outlets for oxidizing or flamn.nble gases shall be located at a distance ofat least 0.2 m frolr the outlet (centue to centle), so as to minimize the risk ofignition of flammable gases.
278
NOTE:
:
Requirernents BS EN 6060 I,
i
tbr ME equipment for use in conjulction with
flaltrmab]e
7'10.514.9 Diagrams and documentation 710.514.9,1 Plans ofthe electrical installation togetherwith records, drawings, wiring diagrams and modifications relating to the medical location, shal1 be provided. Information provided shall include but not be limited to:
(i)
single-line ovewierv diagrams showing the distdbution system of the normal supply for safety services in a single-line representation
pow
supply and power
(ii) distribution board block diagrams showing switchgear and controlgear and distribution boards in
a single-
line representation
(iii) schematic diagrams of controls (i") the verification ofcompliance with the requirements of standards (u) functional description for the operation ofthe safety power supply sewices and ofthe safety power supply
.
.ir.
system.
Selection and erection of uriring systems
710.52
\ny wi ng system within Group 2 medical locations shall be exclusively for the use of equipment and accessorres \\ itlin those locations.
710.53
Protection, isolation, switching, control and monitoring 710.531.2 Overcurrent protective devices - protection of wiring systems in medical locations of Group 2
Overload currenl protection shall not be used in either the primary or secondary circuit of the transformer of a :nedical IT system. O\ ercurent protection against overload and shofi-circuit curents is required for each final circuit. NOTE 1: Overcurrent protective devices (e.g. fuses) may be used in the primary circlrit of the lraDsformer for short-circuit protection only. NOTE 2: Fig 710.3 shows a typical medical IT system anangement.
.3
710.531
RCDS
710.531.3.2 Socket-outlets protected by RCDs
::::!1:'
r:..:.-d ,-..,:,- .j
circuit protected by an RCD having the characteristics specilied in Regulation 415.1.1, consideration shall given :e to reduce the possibility ofunwanted tripping of the RCD due to excessive protective conductor culTel]ts :roduced by equipment during normal operation.
_- -t->
710.537
- or each
:.:-.111
lsolation and switching
710.537.'l General
:. - r.t:
\uromatic chalgeover devices shall comply with BS EN 60947-6-l and shall be auanged so that safe separation :etu,een supply lines is maintained.
7'10.55
Otherequipment 710.553.1 Socket-ou et circuits in the medical lT system for medical locations of Group 2 >!.,cket-outlets intended to supply ME equipment shall be unswitched.
.\i
each patient's place
(i) tii)
oftreatmelt,
e.g. bedheads, the configulation of Socket-outlets shall be as follows:
Each socket-outlet supplied by an individually protected circuit, or several socket-outlets sepamtely supplied by a urinimum oftwo circuits.
Socket-outlets used on medical IT systems shall be coloured blue and be clearly and pemanently marked 'Medical I qurpment Only'.
!{OTE:
^L
Supportirg infonnation is given
ir HTM
06-01.
710.559
Luminairesandlightinginstallations
Ir
medical Iocations ofGroup 1 and Group 2, at least two different sources of supply shalt be provided. One sources shall be connected to the electdcal supply system for safety services.
710.56
ofthe
Safety services
Apower supply for safety services is reqr"rired v'hich will n.raintain the supply lor continuous operation for period u ithin a pre-sel changeover rirne.
a
defined
The safety power supply system shall automatically take over ifthe voltage ofone or more incoming live conductors, at the main distribution board of the building, has dropped for more than 0.5 s and by more than l0 % in regard to the nominal voltage.
NOTE:
A list ofexarnples with suggested reinstatcment times is given in Table A7l0 ofAnflex A710.
710.560.4 Classification Classificatiou of safety services is given in Regulation 560.4.1.
NOTE:
Safety sen'iccs provided lor locations having differing classifications should meet that classillcation which gives the highest security of supply.
710.560.5.5 General requirements for safety power supply sources of Group 1 and Group 2 Primary cells are not allowed as safety power sources.
An additioual main incoming power supply. flom the general power supply, is not regarded as a source ofthe salety power supply. The availabiiity (readiness for senice) ofsafety power sources shall be monitored and indicated at a suitable location.
710.560.5"6 In case ofa failure ofthe general power supply source, the power supply for safety services shall be energized to feed the equipment stated inRegulations 710.560.6.1.1 to 3 with electrical energy for a defined period of time and within a predetemined changeover period. 710.560.5'7 Where socket-outlets ale supplied fl'orn the safety power supply source they shall be readily identifiable according to their salety services classification.
710.560.6 Electrical sources for safety services 710.560.6.1 Detailed requirements for safety power supply services
NOTE:
Also refer to Regulation 710.560.5.5.
710.560.6.1.'l Power supply sources with a changeover period less than or equal to 0.5 s In the event of
a voltage failure on one or mol€ line conductors at the distribution board, a safety power supply source shall be used al1d be capable ofproviding power for a period ofat least 3 h for the following:
(i) (ii)
Luminaires oloperating theatre tables
ME equipment containing light sources being essential for the application ofthe equipment, e.g. endoscopes, including associated essential equipnent, e.g. monitors
(iii)
Life-supporting ME equipurent.
The duration of 3 h may be reduced to Regulation 710.560.6.1.2 is installed.
I
h for items (ii) and (iii)
if
a power source meeting the requirements
of
The nomral power supply shall be restored within a changeover period not exceeding 0.5 s. NOTE: Supporting informatiol] relating to the autonomy of battery inverter units for theatre llrninaires is given in HTM 06-01.
710.560.6.1
.2
Power supply sources with a changeover period less than or equal to 15 s
Equipment meeting the requirements of Regulations 710.560.9.1 and 710.560.1I shall be connected within l5 s to a safety power supply source capable of naintaining it for a minimum period of24 h, when the voltage of one or more live conducto$ at the main distribution board lor the safety senr'iaes has decreased by more than 10 % ofthe nominal value of suppl1, voltage and for a duration greater than 3 s.
284
710.560.6.1.3 Power supply sources with a changeover period greater than 15 s Equipment, other than that covered by Regulations 710.560.6.1.1 and 710.560.6.1.2, which is required for rhe maintenance of healthcare installations, shall be connected either automatically or manually to a safen po.,.er
supply source capable ofmaintaining it for a minimum period of24 h. This equipment may include, lor example:
(i) (ii)
Ste lization equipment Technical building installations, in particular air conditioning, heating and ventilation systems, buildins services and waste disposal systems
(iii)
Coolingequipment
(iY)
Cateringequipment
(v)
Storage battery chargers.
710.560.7 Circuits of safety services The circuit which connects the power supply source for safety services to the [rain distribution board shall be considered a safety circuit.
710.560.9 Emergencylightingsystems 71
0.560.9.1 Safety lighting
In the event of mains power failure, the changeover period to the safety services source shall not exceed
necessary minimum illuminance shall be provided for the following:
(i) (ii)
(iii) (
iv) (v)
(vi)
l5 s. fhe
Emergency lighting and exit signs
Locations for switchgear and controlgear for emergency generating sets, for main distribution boards ofthe normal power supply and for power supply for safety services Rooms in which essential services are intended. In each such room at least one luminaire shall be supplied from the power source for safety services
Locations of centml fire alarm and monitodng systems Rooms ofGroup I medical locations; in each such room at least one luminaire shall be supplied from the power supply source for safety services Rooms ofGroup 2 medical locations; a minimum of90 % ofthe lighting shall be supplie6lrom the power source for safety services.
The luminaires ofthe escape routes shall be arranged on alternate circuits,
710.560.11 Other services other seryices which may require a safety seruice supply with a changeover period not exceeding l5 erample, the following:
(i) (ii) (iii) (iv) (v)
s
include, tbr
Firefighters 1ifts Ventilation systems for smoke extraction Paging/communication systems
ME equipment used in Group 2 medical locations which serves for surgical or other procedures of vital importance. Such equipment will be defined by responsible staff
Electrical equipment
of medical gas suppry including
compressed air, vacuum supply and narcosis
(vi)
(anaesthetics) exhaustion as well as their monitoring devices Fire detection and fire alarms
(r,ii)
Fire extinguishing systems.
710.6
lnspection and testing
NOTE: The
testing of equipment connected to the electrical installation is or.rtside the scope of this document. For ME equipment refer to BS EN 62353.
710.64
lnitialverification
710,641
ceneral
fhe dates and results ofeach ve flcation shall be recorded.
-
-..*=-
The tests specified below under items (i) to (iii), in addition to the requirements of Chapter 64, shall be caried out, both prior to commissioning and after alteration or repairs and before re-commissioning:
(i)
Complete functional tests of the insulation monitoring devices (IMDs) associated with the medical IT system including insulation failure, transfomer high temperature, overload, discontinuity and the audible and/or visual alams lirked to them
(ii)
Measurements ofleakage curent ofthe output circuit and ofthe enclosure ofthe medical IT transformers in noJoad condition, as specified by Regulation 710.512.1.1(i)
(iii)
Measurements to verily that the resistance ofthe supplementary equipotential bonding is within the limits stipulated by Regul ation 1 10.415.2.2.
NOTE:
The tests specified lvithin HTM 06-01 may also be required as part
710.65
Periodic inspection and testing
710.651
General
ofclient requirements.
NOTE I : In addition to the requirements of Chapter 65, the following procedures are recommended at the given i[ter.r'als:
(i) Annually Complete
functional tests ol the insulation monitoring devices (IMDs) associated with the medical lT system including insulation failure, transfomer high temperature, overload, discontinuity and the audible/visual alarms linked to them
(ii) Annually Measurements to ve fy that the resistance
ofthe supplementary protective equipotential bonding
is within the Iimits stipulated by Regulation 710.415.2.2.
(iii)
Every 3 years Measurements ofleakage current ofthe output circuit and ofthe enclosure ofthe medical IT transfonners in noload condition, as specified by Regulation 710.512.1.1(i)
NOTE 2: Supporring inlormation on periodic inspection and testing is given in HTM 06-01. Client or local Health Authority requiements, if aly. may apply.
Fig 710.1
,/ ,/ ,/ ,/ ,/ ,/ ,/ ,/ ,/ ,/
-
Example of patient environment (BS EN 60601)
1,/ ,/ ,/ ,/ ,/,/
/ / ,. ,/ /
I
NOTE:
282
The dimensions in the figure shor,r' the minimurn extent ofthe patient environment in a free sunounding. This applies where the patient's positiorl is predetemined; if not, all possible patient positions should be considered (see Patient environment, Part 2. Defnitions).
Fi!710.2
-
Typical theatre layout
I I I I I I
---F I
I I
.t tl
tt I
I ll
I
rlrrrr
ll
,,", /
,,,, ,,
#
t;_' '| , osl:l?ld |
Fl'iE:.'
r Ir I r:: F - -"1 '.3a-,--,-- Irrr----tl----__ tt::::::::::::: t____
Fig 710.3
-
Typical medical lT system arrangement
[4EDICAL ISOLATING
TRANSFORMER WITH EARTHED SCREEN
SUPPLEI\,lENIARY EOUIPOTENTIAL BONDING CONNECTION POINTS
N4EDICAL LOCAT]ON ALARI\,4 PANEL
-&L_
EOU POTENTIAL
BOND NG BUSBAR (EBB)
ANNEX A71O
MEDICAL LOCATIONS services of medical locations Examples for allocation of Group numbers and classification for safety
AdefirritivelistofrrredicallocationsshowingtheirassigrredGroupsisinrpracticable,asistheuse-to.which provided as a guide only and should be read locations (rooms) might be put. The acco,'pul'|;ng list ofe"amPles is 7 t 0.3 cannot be satisfied bv using this table in cor.rjunction with Regulation 7 t{t.i. i1," ,"qrit.ir"ntt ot negi tation alone.
TABLE A710
-
List of examples
GlglPMedical location 1 Massage
0
x
room
2 Bedrooms
x x
4 ECG, EEG, EHG roonl
x
5 Endoscopic loont
xb
6 Examination or treatmellt roolr 7 Urology room
u4
therapy room
9 Hvdrotherapy room 10 Physiotherapy room
x.
X
xb
x
x
x x x
17 hteusive care roonl
Haertodialysis roon.t
resonat',."1!9tlgll1ry!99g-
2l Nuclear medicine 22 Premature babY roon]
,1 r-+affia/liqra a,ie I Init IIMCI ll
x x x x
xb
l6 Head catlteterization room
19
15 s
x
15 Operating recor ctY room
Argiographic examination room
I
x
l3 Operating preParation room l4 Oneratins Dlaster room
18
>0.5s
x x
1l Anacslhetic area 12 Opemting theafe
20 Magnetic
!0.5s
2
I
x
3 DeliveD/ room
8 Radiological diagrostrc
Classificatiott
x x x
x
x
x x x x x x
x x x x x x x x
x. x.
x
x
x x
x"
X
x
x
x"
X
x"
x x x x x
a
re quire a power suPPlY within 0.5 s and Specific luminaires. such as operating or procedure lights, that within 0.5 s. life-suppolt medical electrical equiptrrent that requires a Power slrppl)
b
Not beirg an oPerating theatre.
SECTION 711 EXHIBITIONS, SHOWS AND STANDS Scope
711.1
'l I
The paticular requirements ofthis section apply to the temporary electrical installations in exhibitions, shos s and stands (including mobile and portable displays and equipment) to protect users. Unless specilically stated. rhis section does not apply to exhibits for which requirements are given in the relevant standards.
This section does not apply to the fixed electrical installation ofthe building, ifany, in which the exhibition. shou or stand may take place.
This section does not apply to electrical systems as defined in BS 7909 used in stmctures, sets, mobile units etc as used for public or private events, tou ng shows, theatrical, radio, TV or film productions and similar activities of the entefi ainment industry The requirements ofother sections ofPart 7 may also apply.
Assessment of general characteristics
711.3
711.313
Supplies
The nominal supply voltage ofa temporary electrical installation in an exhibition, show or stand shall not exceed 230/400 VAC or 500 V DC.
711.32
Classification of external influences
The extemal influence conditions ofthe particular location where the temporary electrical installation is erected, e.g. the presence ofwater or mechanical stresses, shall be taken into accou[t.
711,41
Protection against electric shock
711.410.3 General requirements 711.410.3.4 A cable intended to supply tempomry structures sl'rall be protected at its origin by an RCD whose rated residual operating curent does not exceed 300 mA. This device shall provide a delay by using a device in accordance with BS EN 60947-2, or be of the type S in accordance with BS EN 61008-l or BS EN 61009-1 for selectivity with RCDs protecting final circuits.
NOTE:
I
The rcquirernent for cable protection relates to the increased risk ofdanage to cables in temporary locations.
711.410.3.5 The protective
measures ofobstacles and placing out ofreach (Section 417) shall notbeused.
711,410.3.6 The protective measures of non-conducting location (Regulation 418.1) and earth-free local equipotential bonding (Regulation 418.2) shall not be used.
71'1.411
Protective measure: Automatic disconnection of supply
7'11,4'l'1.3.1.2 Protective equipotential bonding Structural metallic parts which are accessible from within the stand, vehicle, wagon, caravan or container shali be connected through the main protective bonding conductors to the main earthing terminal within the unit. 7
11.411.3.3 Additional protection
Each socket-outlet circuit not exceeding 32 A and all final circuits other than for emergency lighting shall be protected by an RCD having the characteristics specified in Regulation 415.1.1 .
711.411.4 TN system Except for a paft of an installation within a building, a PME earthing facility shall not be used as the means earthing for an installation falling within the scope ofthis section except where:
(i) (ii)
of
the installation is continuously under the supewision ofa skilled or instmcted person(s), and
the suitability and effectiveness of the means of eathing has been confirmed before the connection is made.
I
711.414
Protective measure: Extra-low voltage provided by SELV or PELV
711'414.4.5 Where SELV or
(i) (ii)
PEl,
s
used, whatever the nominal voltage, basic protection shall be provided by:
basic insulation con.rplying with Regulation 416.1, or by baniers or enclosures complying with Regulation 416.2 and affording a degree ofprotection ofat least
IPXXD or IP.IX.
711.42
Protection against thermal effects
711.422
Protection against fire
7
11.422.4.2 Heat generation
Lighting equipment such as incandescent lamps, spotlights and small projectors, and other equipment or appliances with high temperature surfaces, shall be suitably guarded, and instatled and located in accordaace with thi ielevant standard. Showcases and signs shall be constructed of material having adequate heat-resistance, mechanical strength, electrical insulation and ventilatior, taking into account the combustibility of exhibits in relation to the heat generation.
Stand installations coltaining a concentration of elect cal equipment, luminaires or lamps liable to generate excessive heat shall not be installed unless adequate ventilation provisions are made, e.g. well ventilated ceiling constructed of incombustible material.
In all cases. the manufacturer's instructions shall be taken in to account.
711.5
Selection and erection of equipment Common rules
711.51
Switchgear and controlgear shall be placed in closed cabinets which can only be opened by the use of a key or a tool, except for those pafts designed and intended to be operated by ordinary persons.
71'1.52
Wiring systems
Armouredcables orcables protected against mechanical damage shatl be used wherever there is a risk ofmechanical danrage.
wiring cables shall be copper, have a minimum cross-sectional
area of 1.5 mm2, and shall comply with apptopriate British or Harmonized Standard for either thermoplastic or thermosetting insulated elechic cables.
a11
Flexible cables shall not be laid in areas accessible to the public unless they are protected against mechanical damage.
711.52'l
Types of wiring system
Where no flre alalm system is installed in a building used for exhibitions etc. cable systems shall be either: (i) flalne retardant to BS EN 60332-1-2 or to a releyant pafi ofthe BS EN 60332-3 series, and low smoke to BS EN 61034-2. or
(ii)
single-core or multicore unamoured cables enclosed in metallic or non-metallic conduit or trunking, providing fire plotection in accordance with BS EN 61386 series or BS EN 50085 series and providing a degree ofprotection ofat least IP4X.
711.526
Electricalconnections
711.526.1 Joints shall not be made in cables except where necessary as a connection into a circuit. Where joints are rnade, these shall either use connectors in accordance with relevant standards or be in enclosures with a degree ofprotectior ofat least IPXXD orIP4X. Where stmin can be tmnsmitted to teminals the connection shall incorporate suitable cable anchorage(s).
286
_
711.537
.2
Devices for isolation
711.537.2,3 Every
separate temporary stmcture, such as a vehicle, stand or unit, intended to be occupied bv one
specific user and each distribution circuit supplying outdoor installations shall be provided with its own readill' accessible and properly identifiable means of isolation. The means of isolation shall be selected and erected in accordance with Section 462 and Regulation 537.2.
71'1.55
Otherequipment
711.55.4
Electricmotors
I
711.55.4.1 lsolation Where an electdc motor might give rise to a hazard, the motor shall be provided with an effective means isolation on all poles and such means shalt be adjacent to the motor which it controls (see BS EN 60204-l).
7'l'1.55.6
of
ELV transformers and electronic convertors
A manual reset protective device shall protect the secondary circuit ofeach tmnsformer or electronic convertor. Particular care shall be taken when instatling ELV transformefs, which shall be mounted out of arm's reach ofthe public, e.g. in a panel or room with adequate ventilation that can only be ascessed by skilled or instructed pe$ons. Such access shall be provided only to facilitate inspection, testing and maintenance. Electlonic convefiols shall confom with BS EN 61347-1.
711.55.7 Socket-outlets Where a floor mounted socket-outlet is installed, it shall be adequately protected from accidental ingress ofwater and have sullcient strcngth to be able to withstand the expected trafnc load.
711,559 Luminairesandlightinginstallations 711.559.4.2 ELV lighting systems for filament lamps Extralow voltage
systems for filament lamps shall comply with BS EN 60598-2-23.
711.559.4.3 Lampholders Insulation piercing lampholders shall not be used unless the cables and lampholders are compatible, and providing the lampholders are non-removable once fltted to the cable.
7'11.559.4.4 Electric discharge lamp installations lnstallations of any luminous tube, sign or lamp as an illuminated unit on a stand, or as an exhibit, with nominal power supply voltage higher than 230/400 V AC, shall comply with Regulations 711.559 4.4.1 to 3.
711.559.4.4.'l Location The sign or lamp shall be installed out of arm's reach or shall be adequately protected to reduce the risk
ofinjury
711.559.4.4.2 lnstallation Ihe facia or
stand fitting material behind luminous tubes, signs or laurps shall be non-ignitable.
711.559.4.4.3 Emergency switching device
\
separare circuit shall be used
...i itch. The
to supply signs, lamps or exhibits, which shall be controlled by ar emergency
switch shall be easily visible, accessible and clearly marked.
711.559.5 Protection against thermal effects (arm's reach) from floor level or otherwise accessible to accidental contact -rminaires mounted below 2.5 m .rall be firmly ancl adequately fixed, and so sited or guarded as to prevent sk of injury to persons or ignition of ::aterials.
NOTE:
In the case ofoutdoor lighting installations, Section 71,1 also applies, and a degree ofprolection of at least IP33 may be required.
711.6
lnspection and testing
temporary electrical installations of exhibitions, shows and stands shall be inspected and tested on sire in ::cordance with Chapter 64 after each assembl-v on site.
1e
_"t l
SECTION 712
soLAR PHOTOVOLTATC (pV) POWER SUppLy SYSTEMS Scope
712.1
The particular requirements of this section apply to the electrical installations of PV power supply systems including sl sterns u irh AC module..
NOTE:
Requirements for PV power supply systems which are intended for stand alone opemtion are under consideratioo.
Assessment of general characteristics
712.3 712.31
Purposes, supplies and structure
712.312
System earthing
7'12.3'12.2 Type of earthing arrangement Earthing ofone ofthe live conductols ofthe DC side is pennitted, ifthere is at least simple separation between the AC side and the DC side.
NOTE: Aly
connections with Eafih on the DC side should be electrically connected so as to avoid co(osion
(see BS
EN 13636 and BS EN 15112).
7'12.4 Protection for safety 712.41 Protection against electric shock 7'12.410.3 General requirements PV equipment on the DC side shall be considered to be energized, even when the system is disconnected from the
AC side.
712.410.3.6 The prolective measures of non-conducting location (Regulation 418.1) and eafih-free local equipotential bonding (Regulation 418.2) shall not be used on the DC side.
712.411
Protective measure: Automatic disconnection of supply
712.41'l,3.2,1 .1 On the AC side, the PV supply cable shall be connected to the supply side of the overcurrent protective device for automatic disconnection ofcircuits supplying cuffelt-using equipment. 712.411.3.2.1.2 Where an electrical installation includes a PV power supply system without at least simple separation between the AC side and the DC side, an RCD installed to provide either fault protection by automatic discouection ofsupply or additional protection in accordance with Regulation 415.1.1, lor the PV supply cable, shall be Type B according to BS EN 62423. Where the PV convertor is, by construction. not able to feed DC fault currents into the elect cal installation, an RCD of Type B according to BS EN 62423 is not required.
7'12.412
Protective measure: Double or reinforced insulation
Protection by the use ofClass
712.414
ll
or equivalent insulation shall preferably be adopted on the DC side.
Protective measure: Extra-low voltage provided by SELV or PELV
712.414.1 General 712.414.1.1 For SELV and PELV
712.433 712.433.1
systerns. Uoc STC replaces U0 and shall not exceed 120 V DC.
Protection against overload on the DC side Overload protection may be ornitted to PV string and PV anay cables when the continuous cuffenteqLral to or greater than 1.25 times lsc STC at any location.
canying capacity ofthe cable is
7'12.433.2
Overload protectiol rnay be omitted to the PV rnain cable capacity is equal to or gleater dran 1.25 ti,nes Isc STC ofthe PV generator
288
if
the continuous cunent-carrying
NOTE: Therequiremer1tsolRegulatiom7l2.,l33.land712.433.2areonl)rele\antlorprotectionofthccables.sr:::
:
manut'acturer's instructions for prctection of PV modules.
712.434
Protection against fault current
712.434.'l
The PV supply cable on the AC side shall be protected against fault currer'rt protective device jnstalled at the connection to the AC mains.
712.444
b)
an
l-a\
ii!-:: i-:
Protection againstelectromagneticdisturbances
712.444.4.4
To urinirnize voltages induced by lightning, the area of all wiring loops shall be as smal1 asprr:sibie.
Selection and erection of equipment
712.5
712.51 712.511
Common rules Compliance with standards
712.511.1 PV
rnodules shall conply u,ith the requirements of tl're relevant eqLllrment standard. e.s. 3S EN 61215 tbr crystalline PV modulcs. PV modules ofCiass II construction or with equivalent insulation are ::conrmended if Un. src ofthe PV strings exceeds 120 V DC.
re PV aray junction box, PV generator .junctioll box and switchgear assenrblies shall be in coupliance with
.
3S EN 6i439-1.
712.512
Operational conditions and external influences
712-512.1.1 Electrical equipment on the DC side shall be suitable for direct voltage
and direct current.
-\
nrodules rnay be connected in series up to the maximum allowed operating voltage ofthe PV rrodules (Uoc src ilre PV strings) and the PV convelk)r., r'vhichever is lower. Specifications fbr this equipment shall be obtailed r.'m the equipl'nent rnanufacturer.
: :locking diodes are used, their levcrsc voltage shall
-
,des shall be connectcd
be rated for 2 x Uoc sTC of the PV string. The blocking
in scrics with thc PV strings.
-'12.512.2.'l As spccificd by thc rnanufacturer. the PV modules shall be installed in such a way that there is ,:3.luate heat dissipation undcr conditions of maximum solar mdiation lor the
si1e.
-12.5'13 Accessibility -12,513.1 Thc sclection and er-ectiol'r of equipment shall facilitate safe l'naintenance and shall not adversely ':;t provisions rnade by the manulacturer ol'the PV equipment to enable maintenance or service work to be - - rccl out safeJy.
-12.52
Selection and erection of wiring systems
-12.522
Selection and erection of wiring systems in relation to external influences
-'2.522-8.1 PV string cables, PV arra), cables and PV DC - :rrize the sk ofearlh faults and short-circuits.
\CTE:
main cables shall be selected ard erected so as to
This lna), be achieved. fol example, by reinforcing theprotection ofthe wiring against extemal irfluences by the use of single-core sheathed cables complying with BS EN 50618.
-'2.522.8.3 Wirirg systens shall withstand the expected extemal influences -
-::.rature and solar radiation.
-'2,53 -'2.537 -'
2.537
.2
such as wind. ice formatiot,
Protection, isolation, switching, control and monitoring lsolation and switching Devices for isolation
-'2.537.2.1.'l To allow maintenalce of the PV convertor, rreans of isolating the PV convefior from the DC . ..nd thc AC sidc shall be provided. \lTE: Futher reqLrilenrents rvith regard to thc isoiation ofa PV i11stallation operatinc i para11e1 u,ith the public sLrppN systen are eiven in Regulalion
551 .7.6.
712.537.2.2.'l ln the
selection and erection ofdevices for isolation and switching to be installed between the PV installation and the public supply, the public supply shall be considered the source and the PV installation shal1 be considered the load. 7'12.537
.2.2.5
A srvitch-disconnector shall be provided on the DC side of the PV convertor.
7'12.537.2.2.5.1 Alljunction boxes (PV generator and PV array boxes) shall carry a warning label indicating that parts inside the boxes may still be live after isolation fiom the PV converlor.
712,54
Earthing arrangements and protective conductors
Where protective bonding conductors are installed, they shall be parallel to and in as close contact as possible with DC cables and AC cables and accessories.
;90
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Fig712.1
-
PV installation - General schematic - One array
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292
SECTION 714 OUTDOOR LIGHTING INSTALLATIONS 714.1
Scope
This section applies to outdoor lighting installations comprising one or more lutninaires. a wiring system and accessories, and to highway power supplics and street fumiture.
The following ale included in outdoor lighting installations:
(i) (ii)
Lighting installations such as those for roads, parks, car parks, gardens, places open to the public, sporting areas. illumination of monurrents and floodlighting Other lighting affangements in places such as telephone kiosks, bus shelters, advertising panels and town plans
(
iii)
Road signs.
Thc following are excluded:
(iv) Temporary festoon lighting (v) Luminaires fixed to the outside of a building and supplied (vi) Road tramc signal systems. 714.4
Protection for safety
714.41
Protection against electric shock
directly from the intemal wiring of that building
714.4'10.3 General requirements 714.4'10.g.6 The protective measures
of
non-conducting location (Regulation 418.1) and earth-free local
equipotential bonding (Regulation 418.2) shall not be used.
7'14.411 Protective
measure: Automatic disconnection of supply
714.411.20'l Where the protective neasure automatic disconnection ofsupply is used. all live pafis ofelectrical cquipment shall be protected by insulation or by bauiers or enclosrues providing basic protection. A door in street t'urniture, used for access to electrical equipment, shall not be used as a barier or an enclosure.
7'14.411.202 A lraximuur disconnectiorl time of 5 s shall apply to all circuits feeding flxed equipment used in highway power supplies for compliance with Regulation 41 I 3.2.3 (TN system) or 4l1.3.2.4 (TT system)
714.411.203 Where an earlh connection to a distdbuto/s PME network has been provided for a street electrical fixtul.e, tlte earthing and bonding conductor of a street elect cal flxture shall have a minimum copper equivatent cr.oss-sectional area of 6 nrmz for supply neutral conductors with copper equivalent cross-sectional areas up to l0 mm:. For larger sized supply neuhal conducton the main bonding shall comply with Table 54.8.
714.411.2.201 Provisionsforbasic protection For every accessible erclosure livc parts shall only be accessible with a key or a tool, unless the enclosule is in location where only skilled or instructcd person(s) have access.
a
A door giving access to electrical eqBipment and located less than 2.50 m above ground level shall be locked with a key oi shall require the use of a tool for access. In addition, basic protectior shall be ptovided when the door is open either by the use of equipment having at least a degree of protection IPXXB or IP2X by construction or by installation. or by installing a banier or an enclosure giving the same degree ofprotection. For a lullinaire at a height of less than 2.80 m above ground level, access to the light sou|ce shall only be possible after removing a barrier or an enclosure requiring the use of a tool.
714.411,3.1 Protective earthing and protective equipotential bonding 7
1
4,4'l'1.3.1.2 Protective equipotential bonding
grid etc.). which is ir the proximity ofbut is not part olthe outdoor lighting illsta]lation need l]ot be connected to the main eafihing terminal.
A metallic stmcture (such
71
as a fence.
4.4'l'1.3.3 Additional protection
Lighting in places such
as telephone kiosks. bus shelters,
advertising panels and tou n plans shall be provided with
additional plotection by ar RCD having the characteristics specified in Regulation
II5'1
I
-
2gB
7'14.5 Selection and erection of equipment 714.51 Common rules 714.512
Operational conditions and external influences
714.512.2 External influences 7'14.512.2,1 The following classes are generally recommended: (i) Ambient temperature: AA2 and AA4 (from -40 "C to +40 'C) (ii) Climatic conditions:AB2 andAB4 (relative humidity between 5 % and 100 %)' a deglee ofplotection of 714.512.2.105 Electrical equipment shall have, by constluction oI by installation,
I
at
least IP33.
I
714.514.12 Notices 714,514.12.201 The requirements for notices for:
(i) (ii)
periodic inspection and testing (Regulation 514 12 1) and the testing ofRCDs (Regulation 514.12.2)
and testing procedure need not be applied where the installation is subject to a plogrammed inspection
durable label stating the 714.514.12.202 On every temporary supply unit there shall be an extemally mounted maximum sustained cunent to be supplied from that unit'
714.537
lsolation and switching
714.537.2 Devices for isolation 714.537.2.1 General
live supply 714.537.2.1.1 Every circuit shall be capable of being isolated individually from each of the conductors, except as detailed in Regulati,on 461.2.
pe$ons Where it is intended that isolation and switching is carried out only by instructed being fiom equipment prevent any to taken be precautions can and subject to suitable provisions being made so that the means load and on supply the of switching the means inadvertently or uninte,tionally energiied, for TN sysiems, olisolation is permitted to be provided by a suitably rated fuse carrier
7'14.537.2.1.201
power Where the distributor's cut-out is used as the means of isolation of a highway supply the approval olthe distributor shall be obtained' 714.537 .2.1.202
r"'-'\ f;
uramnv B
rO)
I I I
I
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SECTION 715
EXTRA.LOW VOLTAGE LIGHTING INSTALLATIONS
715.1
Scope
This section applies to extraJow voltage Iighting installations supplied from a source with of50 VAC or 120 V DC.
715.4 7'15.41 7'l 5.411.7
a
maximum mted voltage
Protection for safety Protection against electric shock
.20'l
Fu
nctional extra-low volta ge (FELV)
FELV shall not be used.
715.414
Protective measure: Extra'low voltage provided by SELV or PELV
An ertra-low voltage luminaire without provision for the connection of
a protective conductor shall be installed
only as pat of a SEiV system. Where bare conductors are used, the nominal voltage shall not exceed 25 V AC or 60 V DC according to Regulation 414.4.5. A safety isolating transformer for an extra-low voltage lighting installation shall comply with BS EN 61558-2-6 and shall meet at least one of the requirements of Regulation 71 5 422.106. NOTE I : For an explanation of symbols used see Table 5 5.3.
parallel operation of fansformers in the secondary circuit is allowed only ifthey are also paralleled in the primary circuit and the transformers have identical electrical characteristics.
An electronic convertor for an extm-low voltage lighting installation shall comply rvith BS EN 61347 -2-2. Annex for incandescent lamps ol BS EN 61347-2-13, Annex I for LEDs. NOTE 2: For an explanation ofsymbols used
:!11)
7
see Table 55 3.
Parallel operation ofconvefiors to BS EN 61347-2-2 or BS EN 61347-2-13 is not permitted'
715.42
llitrtlS
Protection against thermal effects
715.422.106 Fire risk of transformers f_i:1t1S
Transfomers shall be either:
po\ref
(i)
protected on the primary side by a protective device complying with the requirements 7 15.422.10',7 .2, or
(ii)
short-circuit proof (both inherently and non-inherently).
NOTE:
of Regulation
For an expJanation ofsymbols used see Table 55 3.
715,422.107Fne risk due to short-circuit 715.422.'107.1 where both the live circuit conductors
(i)
they shall be provided with
a
are
uninsulated, either:
protective device complying with the requirem€nts ofRegulation 715.422.10'7.2'
OI
(ii) (iii)
they shall be supplied from
transformer or converlor, the power ofwhich does not exceed 200 VA, or
the system shall comply with BS EN 60598-2-23.
715.422.107
(i) (ii)
a
.2
A device providing protection against the risk offire shall meet all the following requirements:
The device shall continuously monitor the power demand olthe luminaires The device shall autofratically disconnect the supply circuit within 0.3 s in the case of a short-cjrcuit or
failure which causes a power increase of more than 60 W
(iii) (iv)
power The device shall provide automatic disconnection while the supply circuit is operating with reduced a which causes (for example, by gating control or a regulating process or a lamp failure) ifthere is a failure power increase ofmorc than 60 W a failure The device shall provide automatic disconnection upon connection ofthe supply circuit ifthere is
which causes
(v)
power increase olmore than 60 W
The device shall be fail-safe.
NOTE:
3-
a
Account needs to be taken of staning culTents.
715.43
Protectionagainstovercurrent
715.430.104 Self-resetting overcurrent proteclive devices The use of self-resetting overcuflent protective devices is pennitted only for transformers up to 50 VA.
715.5
Selection and erection of equipment
715.52
Wiring systems
715.521
Types of wiring system
715.521.1
(i) (ii) (iii) (iv) (v) (vi)
The following wiring systems shall be used:
lnsulated conducto$ in conduit systens according to BS EN 61386 series or cable trunking/ducting systems according to BS Fl\ 50085 .eries
Rigid cables Flexible cables Systems for ELV lighting according toBS EN 60598-2-23
Track systems according to BS EN 60570 Bare conductors (see Regulation 715.521.106).
Where parts ofthe ELV lighting installation are accessible, the requirements olSection 423 also apply.
Metallic stluctural parts of buildings, for example pjpe systems, or parts of fumiture, shall not be used as lir,e conductors. 7 1
5.521,1 06 Bare conductors
Ifthe nominal voltage
does not exceed 25 V AC or 60 V DC, bare conducton may be used provided that the extralow voltage lighting installation complies with all the following requirements:
(i) (ii) (iii)
The lighting installation shall be designed, and installed or enclosed in such a way that the risk ofa shoficircuit is reduced to a minimum The conductors used shall have a cross-sectional area according to Regulation 715.524 The conductors shall not be placed dilectly on combustible material.
For suspended bare conductors, at least one conductor and its terminals shall be insulated for that part ofthe cfucuit between the transformer and the shoft-circuit protective device to prevelt a shofi-circuit. 7 1
5.521.1 07 Suspended systems
Suspension devices for extralow voltage luminaires, including supporting conductors, shal1 be capable of carrying five times the mass ofthe luminaires (including their lamps) intended to be suppofied, but not less than 5 kg.
Tenninations and connections ol conductors shall be made by screw terminals or screwless clamping devices complying with BS EN 60998-2-1 or BS EN 60998-2-2. Safety ofthe installation due to expected stresses in the conductors shall be in accordance with Regulation 559.5.2.
Insulation piercing connectors and termination wires which rely on counterweights hung over suspended conducton to maintain the elect cal connection shall not be used.
The suspended system shall be fixed to walls or ceilings by irsulated distance cleats and shall be continuously accessible tkoughout the route.
715.524
Cross-sectional area of conductors
715.524,20'l The minimum cross-sectional area of the ELV conductors for connection to the output teminals or terminations of tmnsfomers/convefiors sha1l be chosen according to the load current. In the case of systems with luminaires suspended fi'om the conductors, the minimum cross-sectional area of the ELV conductors for connection to the output teminals or terminations of transformerc/convertors shall be 4 mm:. for mechanical reasons.
296
715.525
Voltage drop in consumers, installations
In ELV lighting installatiotts. if the r,oltage drop betu'een the transtbmrir ano ih: t'unhest lumina edoesnotexceed 5 % ofthe nominal voltage ofthe ELV installation it shall be deemed ro corrph * irh secrion 525.
7'15.53
Protection, isolation, switching, control and monitoring
715.530.3 General and common requirements 715.530.3,104 Protective devices and SELV sources Plotective devices may be located above false ceilings, w}rich are removable or easily accessible, provided that infomation is given about the presence and location of such devices. SELV sources, pl-otective devices or similar equipment mounted above false ceilings or in a sinilar place shall be pennanently connected. SELV sources and their protective devices shall be installed so as to: avoid mechanical stress on theil. electrical connections, and
(i) (ii) (iii)
be adequately supporled. and
avoid overheating ofthe equipnrent due to themal insulation.
715.537
Isolation and switching
715'537.1.1 Wher€ transformers are operated in parallel, the primary circuits shall a con.rmon
isolaring device.
be permanently connected to
SECTION 717
MOBILE OR TRANSPORTABLE UNITS 7'17.1
Scope
The particular requirements ofthis section apply to AC and DC installations for mobile or transpofiable units. For the purposes ofthis section, the term 'unit' is intended to mean a vehicle and,/or mobile or transportable structue in which all or part ofan electfical installation is contained.
IJnits are either:
(i) (ii)
ofthe mobile type, e.g. vehicles (self-propelled or towed), or ofthe transportable type, e.g. containers or cabins.
Examples of the units include technical and facilities vehicles for the entertainment industry, medical or health screening services, welfare units, promotion & demonstration, firefighting, workshops, offices, transportable catedng units etc. The requirements are not applicable to:
(iii) (iv) (v) (vi) (vii) (viii)
generating sets marinas and pleasure craft
mobile machinery in accordance with BS EN 60204-
1
caravans to Section 721
traction equipment ofelectric vehicles electrical equipment lequired by a vehicle to allow it to be driven safely or used on the highway.
Additional requirements shall be applied where necessary for units including showers, or for medical locations, etc.
NOTE:
Guidance on temporary electrical systems for events, entertainment and relaied purposcs is given in BS 7909.
717.132
Design
The design of the installation within a mobile or transportable unit shall take into account the charactefistics of the variety of supplies to which the unit might be connected and any limitation shall be clearly stated ir the user documentation. See also Regulation 717.514.
7'17.313 Supplies One or more ofthe following methods shall be used to supply a unit:
(i)
Connection to a low voltage generating set, located inside the unit, in accordance with Section 551 (see Figure 717.I )
(ii)
Connection to a low voltage electrical supply extemal to the unit, in which the protective measures are effective (see Figure 717.3), the supply derived from either a fixed electrical installation or a generating set in accordance with Section 551
(iii)
Connection to a 1ow voltage electrical supply external to the unit, and where intemal protective measures are provided by the use of simple separation, in accordance with Section 413 (see Figures '717 .4,7l7 .5,717.6 and 717.7 showing altemative forms offault protection within the unit).
NOTE 1: tn cases (i), (ii) and (iii), an earth electrode may be provided where supplies are used extemal to the vehicle (see Regulation 717.41 1.4).
NOTE 2: tn the case ofFigure 717.4,
an earth
electode may be necessary for protective pur?oses (see Regulatio n717 .411 .6.2(1i)).
NOTE 3: Simple separation or electrical separation is approp ate, for example, where information techno)ogy equipment is used in the urit or where a reduction of electromagnetic disturbances is necessary or if high protective conductor culTents are to be expected (use of frequency converto6), and/or if the srLpply to the unit comes florn altemarile supply systems (as is the case in disaster management). The sources, means ofconnection or separation may be within the unit. NOTE 4: Where there is a potential hazard due to moving the unit whilst connected to ar extemal installation, it is recommended that the unit is equipped $,ith
a11
electrical interlock, waming, alarm or other appropriate means to reduce
the
sk.
NOTE 5: For the purpose ofthis sectior, power inverters or frequency convertors supplied frorn the unit's electical system or an auxiliary systen dri\en by the unit's prime mover are also considered as generating sets.
298
Power inverters or frequency conveftors shall include electrical separation where both the DC supply and the AC neutral point are earthed.
717.4 Protection for safety 717,41 Protection against electric shock 717.410.3 General requirements .410.3.5
717
717.410.3.6
The protective measures of obstacles and placing out of reach (Section 417) sha1l not be used. The protective measure of non-conducting location (Regulation 418.1) shall not be used.
The protective measure ofearth-free local equipotential bonding (Regulation 418.2) is not recommended.
717.411
Protective measure: Automatic disconnection of supply
717.411.1 General For a supply in accordance with 717.3 l3(ii), automatic disconnectior of supply shall be provided by means of a residual current protective device, with a rated residual operating cunent not exceeding 30 mA. 7
17.411.3.1.2 Protective equipotential bonding
Accessible conductive parts ofthe unit, such as the conductive structure ofthe unit, shall be connected through the main protective bonding conductors to the main earthing terminal within the unit. The main protective bonding conductors shall be finely stranded.
NOTE:
Cable types H05V-K and H07V-K to BS EN 50525-2-31 are considered appropriate.
717.41'1.4 TN system
{ PME earthing facility shall not be used as the means ofearthing for an installation falling within the scope ofthis section except where:
(i)
the installation is continuously under the supervision of a skilled or instructed person(s), competent in such
(ii)
the suitability and effectiveness ofthe means of earthing has been conflrmed before the connection is made.
work, and
717
.411.6
lT system
717.411.6,2 An IT system can be provided by: (i) an isolating translomer or a low voltage genemtirlg set, with an insulation monitoring device or an insulation fault location system, both without automatic disconnection olthe supply in case ofthe first fault and without a need of connection to an earthing installation (see Figure 717.7); the second fault shall be automatically disconnected by overcurrent protective devices according to Regulation 41 1.6.5, or
a transformer providing simple separation, e.g. ir accordance with BS EN 61558-1, with an RCD and an earth electrode installed to provide automatic discolnection in the case of failure in the transformer providing the si[rple separation (see Figvre7l7.4)
717.413
Protectivemeasure: Electricalseparation
:
:ctrical separation can be provided by the use of a transformer providing simple separation, e.g. meeting the :.::irements of BS EN 61558- 1, in accordance with Regulation 4t 3.1.3. It shall be used only where: ,
i
)
an insulation monitoring device is installed to provide automatic disconnection of supply in the case of a flrst lault between live pafts and the conductive sixcture ofthe unit (see Figure 717.5), or
an RCD and an eafih electrode ale installed to provide automatic disconnection in the case of lailure in the tmnsfomer providing the electrical separation (see Figr.rre 717.4). Each socket-outlet intended to supply cu[ent-using equipmeut outside the unit shall be protected indilidually by an RCD having the characteristics specified in Regulation 415.1.1.
-' 7.415 Additional protection ''1
-'
415.1 Additional protection by an RCD having the characteristics specifi ed inRegulation 415.1 . 1 , shall be :ied for every socket-outlet intended to supply current-using equiprnent oursjde the uni1, with the exception of -..i:-outlets which are supplied fiom circuits with protection b),:
299
(i) (ii r liii)
SEL\. or PELV. or
electrical separation, with an insulation monitoring device; see Regul atron 717 .413(i).
7'17,5 Selection and erection of equipment 717.51 Commonrequirements 717.514
ldentificationandnotices
A pemunent notice of such duable material as to be likely to remain easily legible throughout the life of the installation. shall be fixed to the unit in a prominent position, preferably adjacent to each supply idet connector The notice should state in clear and unambiguous tems the foliowing:
(i) (ii) (iii) (iv) (v)
The types ol supply which may be connected to the unit and any limitations on use imposed by the desigrer The voltage rating ofthe unit The number of supplies, phases and their configuration The on-board earthing arangement The maximum power recluirement ofthe unit.
717.52
Wiring systems
717.52.1 Where the supply to the mobile or transportable unit is provided by means of a plug and socketoutlet, flexible cables in accordance with H07RN-F (BS EN 50525-2-21), or cabtes of equivalent design, having a minimum cross-sectional area of 2.5 mm: copper, shall be used for connecting the unit to the supply. The flexible cable shall enter the unit by an insulating inlet in such a way as to minimize the possibility ofany insulation darnage or fault which might energize the exposed-conductive,parts ofthe unit. 7'17.52.2 The wiring system shall be installed using one or more ofthe following: (i) Unsheathed flexible cable with thermoplastic or themosetting insulation to BS EN 50525-2-31, -3-3 | or BS EN 50525-3-41 installed ir conduit in accordance with the appropdate part olBS EN 61386 series or in trunking or ducting in accordance with the appropriate part ofBS EN 50085 series
(ii)
Sheathed flexible cable with themoplastic or thermosetting insulation to BS EN 50525-2-1 l, -2-21, -3-ll or -3-21, ifprecautionary measures are taken such that no mechanical damage is likely to occur due to any
sharp-edged parls or abrasion.
All cables shall,
as a
minimum, meet the requirements ofBS EN 60332-l-2.
Conduits shall comply with BS EN 61386-21, BS EN 61386-22 or BS EN 61386-23.
717.528,3 Proximity to non-electrical services 717.528.3,4 No electrical equipment, including wiring systems, except ELv equipment for gas supply control, shall be installed in any gas cylinder storage compafiment.
ELV cables and elect cal equipment may only be installed within the LPG cylinder compartment ifthe installation seNes the operation ofthe gas cylinder (e.g. indication ofempty gas cylinder) or is for use within the compartmert. Such electrical installations and components shall be colstructed and installed so that they are not a potential source
ofignition. Where cables have to run through such a compartment, they shall be protected against mechanical damage by installation within a conduit system complying with the appropriate part of the BS EN 61386 series or within a ducting system complying with the appropriate part ofthe BS EN 50085 series. Where installed, this conduit or ducting system shall be able to withstand an impact equivalent to AG3 without visible physical darnage.
717.55
Other equipment
717.55,1 Whele the meals ofconnection is a plug and socket-outlet, mounted, accessed or used outside the unit and used to connect the unit to the supply, or supply other equipment, it shall comply wittr the appropriate parts ofBS EN 60309-2 series and shall meet with the following requirements: (i) (ii)
300
Plugs shall have an enclosure of insulating material
Connecting devices, plugs and socket-outlets, with an enclosure as necessary shall afford a degree
ol
l
prctectiol ofat
least IP44 when itr use or connected and protection ofat least IP55 when not connected. e.s. when the unit is in transit
(\\) The \n\er \N\rh'n-ra\C contacts) 717.55.2 Not u.sed
sha\l
be s\tuated on the unit.
717.55.3
Generating sets able to pr-ocluce voltages other than SELV or PELV, rrounted in a mobile unit. shall automatically be switched off in case of an accident to the unit (e.g. event causing the release of airbags). If t)ris requirement is difficult to implement an ernergency switch, easily accessible, shall be installed.
717.551.6 Additional requirements for installations where the generating set provides as a switched alternative to the normal supply to the installation
a
supply
Live conductors fronl differelt powel supplies shall not be interconnected. Protective conductors. including functional earthing conducto$, from differ.ent earthing systems shall only be interconnected where suitable precautions have been taken into account; see also Regulation 542.1.3.3. Plugs and sockct-outlets shall comply with the approp ate pafis ofBS EN 60309 series, except those intended lor special equipment, such as broadcasting equipment where combined connectors for infonnation signals and power suppiy are used.
717.551.7.2 Additional requirements for installations where the generating set may operate in
parallel with other sources including systems for distribution of electiiciiy to the
public
A generating set rised the supply side
ofall
as an
additional source of supply in parallel with another source shall only be connected ofthe installation.
the protective devices for the final circuits
o[
Plotective conductors, including fllnctional earthing conductors, from different eafihing systems shall only be intercomccted where suitable precautions have been taken into account; see also Reculalion 542. L3.3.
Fig 717 .1 - An example of a connection to a low voltage generating set located inside the unit, with or without an earth electrode
L1
L2 L3 N
PE
i ltIIl:A.
6
-/E
Fig 717.2
-
ReseNed for future use
Fig 717.3 - An example of a connection to a low voltage electrical supply external to the unit in which the protective measures are effective, the supply derived from either a fixed electrical
installation or a generating set, with or without an earth electrode at the unit
".:"..i,
,n
I
",,"1
NOTE:
Where a PME ealthirg facility is used, see Regulation 717.411.4.
Fig 717 .4 - An example of a connection to a low voltage electrical supply external to the unit, derived from either a fixed electrical installation or a generating set with any type of earthing arrangement using simple separation and an internal lT system, with an earth electrode
:rIslffi r
-/-€r\
140
342
fl11-!------i=|
L1
L2 L3
unit, Fig 717.5 - An example of a connection to a low voltage electrical supply external to the -uiing and device monitoring an insulation with lT system simpte sep"r"tion and an internal electrode earth with fault, of a first occurrence on the supply autimatic disconnection of
6l z-<3-") 14
to the unit, Fig 717.6 - An example of a connection to a low voltage electrical supply external separation simple with TN system internal iitn any type of earthing arrangement using an
e unit' rrthing 'ode
Fig717,7 - An example of a connection to a low voltage electrical supply external to the unit, with any type of earthing arrangement using simple separation with an internal lT system with automatic disconnection on the occurrence of a second fault
t-,a
,-r-<{l 3-ilfl
304
Key to Figures 717.1
to7
1a
Connectior ofthe unit to an extemal supply through an on board translbrmel with simple separation
1b
Connection ofthe unit to a supply in which the protective measures are effective
lc
Connection to an LV genemtor set in accordance with Section 551
2
Class
II or equivalelt
etrclosure up to the first protective der ice
providilg automatic disconnection of
sLrpply 4
Conductive extemal staircase, if any
5
Connection ofthe neutlal poi[t (or, ifnot available, a line conductor) to the conductive sfucture ofthe unit
6
Socket-outlets for use exclusively witlrin the utrit
6a
Socket-outlets for use exclusively
withi[ the unit for
reasons of
coltinuity of supply in the event of
1]rsr
1'ault
6b
Socket-outlets for general use ifexplicitly required (operation ofthe RCD in the event offlrst farLlt carnor be excluded)
7
Protective equipotential bonding in accordance with Regul at\ot'r 717 .411.3.1.2
7a
to an antenna pole,
7b
to the conductive external stairs, ifany, in contact with the ground
7c
to a functional earth electrode, ifrequired
7d
to the eonductire structule olthe unir
7e
to an earth electrode for plotective purposes, ifrequired
ifany
Protective devices, ifrequired, for overcurrent and/or for protection by disconnection of supply in case
8
of
a second fault 9
Protective devices for overcurent and lor automatic disconnection ofsupply in case
t0
Socket-outlets for cunent-using equipment for use outside the unit
l3 l4 l5
Current-using equipment for use exclusively within the unit
l6a
RCD having the characteristics specified in Regulation 4l5.l.l lor protectior by autornatic discomection ofsupply for circuits of equipntel.rt for use outside the unit
I
6b
ofa
second fault
Ovelcurent protective device, if requiled Overcul-rer)t pr-otective device
RC D
tbr protection by automatic disconnection of supply for circuits of equipnent for use iruide the unit: Wherc an interual IT systen'r is installed. see also Regulation 4l 1.6.4
see Regulations 41 1 .4.4 and 41 I .5.3.
l8 l1 l5a l5b
Main eaflhing lernlinal or bar Transtbrrler u,ith at least sinple sepamtion, e.g. 230 V current-usiug equiprrlerrt lnsulation rronitoting device providing disconnection on the first fault, see Figure 717.5 Insulation tnonitoring device or insulation fault location system including monitoring ofthe N conductor ifdistlibuted (disconnectior ooly in the event ofsecond fault), see Figule 717.7
6iFRro'\ 9-
=-**
"e
"t"*od
SECTION 721 ELECTRICAL INSTALLATIONS IN CARAVANS AND MOTOR CARAVANS NOTE:
ln order nol rc mix reqnirements oll different subjects, such as those for electrical installations ofcaravan parks with thosc fbr el!'ct lcal instaiiatio0s inside caravans. refer to: - Scction 703. which corccrns electrical installations in caravan parks, camping pa*s and similar locations and - Section 7l1. \lhich concems clcctrical installations in caravans and motor caravans.
Scope
721.',|
The parlicular requirenents of this section apply to the electdcal installations of caravans and motor caravans at nourinal voltages not exceeding 230/400 V AC or 48 V DC. They do apply to those electrical circuits and equipment intended for the use ofthe caravan lor habitation purposes.
They do lot apply to those electrical circuits and equipment for automotive purposes, nor to installations covered by BS EN 1648-i and BS EN 1648-2. They do not apply to the electrical installatiors of mobile homes, residential park homes or transportable units. NOTE
l:
Fol rnobile hoLlcs and residential park homes the general requirements apply.
NOTE 2: Fol transportable units see Section 717.
Fol the purposes of this section, caravans and motor caravans are referred to as 'carayans'. Tltc particular requircn'rents of some other sections of Part 7 may also apply to such installations in caravans, e.g. Section 701.
721.31
721.313
Purposes, supplies and structure Supplies
721.3't3.1 .2 l-he noninal supply system voltage shail be chosen from BS EN 60038. The nominal AC supply voltage of the installation of the caravan shall not exceed 230
V
single-phase or 400
V
thrce-pl'rase.
The nominal DC supply voltage ofthe installation ofthe caravan shall not exceed 48 721 .4
Protection for safety
721.4',1
Protection against electric shock
V
721.410.3 General requirements 721.410.3.5
Thc protective measures ofobstacles and placing out ofreach (Section 417) shall not be used.
Ti're protcctive measures ol non-conducting location (Regulation 418.1) and earth-free local equipotential bonding (Rcgulation 418.2) shall not be used. 721.410.3.6
7z',t.41',1
721.411.3.1
Protective measure: Automatic disconnection of supply Protective earthing and protective equipotential bonding
721.4'11.3.1.2 Protective equipotential bonding Structural mctallic parts which are accessible from within the caravan shall be connected through main protective bonding condLrctors to thc ntain earthing tenninal within the carayan.
306
721.413 Protectivemeasure: Electricalseparation The plotective measure ofelectrical separation shall not be used, except for a shaver socket-outlet.
721.414
Protective measure: Extra-low voltage provided by SELV and PELV
Any pafi ofa carava[ installation opemting at extra-low voltage shall comply with the requirements ofSection
-l l-1
For extralow voltage DC power sources, a maximum of 48 V is allowed. In exceptional cases, when AC extra-lo\ voltage is required, the voltage (rms) is not allowed to exceed 48 V NOTE: The requirements of Section 721 ale also app]icable to extra low-voltage DC installations. See Annex A72l for recommendations that may be applied in addition.
:
721.415.1 Additional protection: RCDs
.tt
Where protection by automatic discounection of supply is used, a residual current device with a rated residual
::S.
operating cuffent not exceedirg 30 mA, complying with BS EN 60947-2 (Annex B), BS EN 61008-1, gS fN OtOOq-t or BS EN 62423 breaking all live conductors, shall be provided having the characteristics specified
3:id
in 415.1.1. Each supply inlet shall be directly connected to its associated RCD.
NOTE:
This irnplies that there may not be any taps orjunctions in this connection.
721.43
Protectionagainstovercurrent
72'1.43.1 Finalcircuits Each final circuit shall be protected by an overcurreflt protective device which disconnects all live conductors that circuit.
721.5 721.5'l -:L_10
V
ol
Selection and erection of equipment Gommon rules
721.5'10 lntroduction 721.5'10.3 General Where there is more than one electrically independent installation, each independent installation shall be supplied by a separate connecting device and shall be segregated in accordance with the relevant requirements ofthe Regulations
72'1.514 ldentificationandnotices 721.514,1 General lnstrLlctions fo[ use shall be provided with the caravan so that the caravan can be used safely.
t:
local
The instructions sha)l comprise:
(i) a descriptiol ofthe installation (ii) a dcscliption ofthe furction ofthe RCD(S) and the use ofthe (iii) a descliption ofthe function ofthe main isolating switch (iv) the tcxt ofthe instmctions ofFigure 721. If it is necessary to take precautiots during
test button(s)
user maintenance, appropdate details shall be given.
307
Fig 72't
- lnstructions for electricity supply
INSTRUCTIONS FOR ELECTRICITY SUPPLY TO CONNECT
l.
Ber'ore cornectinglhe cardlrn
(a)
irsollation to thc mains supply. check
rharl
th. suppll n\dilable rt thc cara\m pitch supply point is sritable for the caravan electrical installation and appliances. and
(bl lhc \ollagc. ticqucnc) aid curenr ratings are $itable. ,.i rl,J,.'Ir,,,.,i {'' I'F.n'hrOll pui'ron.
aM
Also. prior to us.. cx!mine th. supply flexiblc cablc to cnsurc rhere is no visible damage or delerioration. 2. Open th. co\ cr to d1c aftliance irlel pro\ided al lhc the ppl! flerit,lc coblc.
l.
caravan
ppty poinl. ifaDy. and inscrl the connector
of
Raisc rhc coler ofnre clecxicil) outlc( pro!ided on rhe pitch supply poiDt and insert the plug oflhe supply cable.
THE CARAVAN SUPPLY FLEXIBLE CABLE MUST BE FULLY UNCOILED TO AVOID DAMAGE BY OVERHEATING 4. Ssirch
on.I lle
5 Che.k
Ihe
carxvaD
mai! isolalirg $rltclr.
op.r.tion of rcsidual cutrent dc\.iccs (RtDs) lirlcd in lhe caravan by presstug lhc
tesi bultonG)
IN CASE OF DOUBT OR, IF AFTER CARRYING OUT THE ABOVE PROCEDURE THE SUPPLY DOES NOT BECOI\TE AVAILABLE. OR IF THE SUPPLY FAILS, CONSULT THE CARAVAN PARK OPERATOR OR THE OPERATOR'S AGENT ORA OUALIFIED ELECTRICIAN.
TO DISCONNECT 6. Srvitcfi offar tfic com\an main isolaling s$irch. uiplug dle cable and then ftonlllc c.raran in]ctconnector
ii6l from
thc caravar pitch srpply point
PERIODIC INSPECTION Prcferably nor less than oncc clcrf thrcc yeas and anDuaLly ifthc caravar is used frequenlLy, thc camvan electrical insrallation and pflI {ble shouklbc nrpcclcd and rested and repon on theircondition obtained as prescribed nr ^ BS 7671 Rcquircnlcnrs tbr Elecni.rl IrstdlldlioDs publishcd by the Inslitution of Engineering and Teclnolos/ & BSL
721.521 721.521.2
(i) (ii) (iii)
Types of wiring system The wiring systems shall be installed using one or more ofthe following:
Insulated single-core cables. with flexible class 5 corductots, in non-metallic conduit
Insulated single-core cablcs. with stranded class 2 conducto$ (minimum of 7 strands), in non-metallic conduit Sheathed flexible cables.
All cables shall,
as a
minimutr, meet the requircments ofBS EN 60332-1-2.
Non-metallic conduits shall cornply with BS EN 61386-21. Cable management systems shall comply with BS EN 61386.
72'1.522
Selection and erection of wiring systems in relation to external influences
721.522.7 Vibration (AH) 721.522.7 .1 As the u,iring will be subjected to vibration, all wiring shall be protected against mechanical damage either by location or by edranced mechanical plotection. Wiring passing through metalwork shall be protected by means of suitable bushes or gromnrcts. securely fixed in position. Precautions shall be taken to avoid mechanical damage due to sharp edges or abrasive parts.
721.522.8 Other mechanical stresses (AJ) cables. urless enclosed in rigid conduit, and all flexible conduit shall be suppofied at intervals not exceeding 0.4 m for vertical runs and 0.25 m for horizontal runs.
72'1.522.8.'1.3 All
308
72'1.524 721-524.1 72'l
.528
Cross-sectional areas of conductors The closs-sectional area of every conductor shall be not less than 1.5
mn:.
Proximity of wiring systems to other services
721.528.1 Proximity to electrical services Cables of low voltage systerns shall be ruIl sepamtely from the cables of extra-low voltage systems, in such a way, so f'ar as is reasonably practicable, that there is no risk ofphysical contact between the two wiring systems.
721.528.2 Proximityto non-electrical services 721.528.2.1 No electrical equipmert, including wiring systems, except ELV equipment for gas supply control, shall be installed in any gas cylinder storage compartment.
ELV cables and electrical equipment may only be installed within the LPC cylinder compartment if the installation seryes the operation ofthe gas cylinder (e.g. indication of empty gas cylinder) or is for use within the compafiment. Such electrical installations and componenis shall be constructed and installed so that they are not a potential source of iglition. height of not
where cables have to ru[ t]rrough such a compartment, they shall pass thlough the compaltment at
a
Iess than 500 mq above the base ofthe withir a colduit system complying with the appropriate paft ofthe BS EN 61386 selies or within
ducting systenl
cylinders and shall be protected against mechanical damage by installaiion a
complying with the appropr iate paft of the BS EN 50085 series. Where installed, this colduit or ductirg system shall be able to withstand ar impact equivalent to AG3 $'ithout visible physical datnage.
721.53 721.537
Protection, isolation, switching, control and monitoring lsolation and switching
72'1.537.2 Devices for lsolation discorurect all live consisting installation I[ an the caravan. within placed ready operation for shall be suitably and which conductors for the requirements fullilling protective device the overcurrent may be isolating switch the 1inal circuit, of only one
721.537.2.1.1 Each installatiorl shall be providecl with a main disconnector which shall
retaliic
isolation. 721.537 .2.1.1.1 A nolice of such durable llaterial as to be likely to remain easily legible throughout the life ofthe installation, shall be permanently fixed near the main isolati[g switch inside the caravan. bearing the text shown in Figure 721 in the approp ate language(s) in indelible and easily legible characters.
721.543
Protectiveconductors
721.543.2 Types of protective conductor with 721 .543.2.1 Circuit protective concluctors shall be incolporated in a multicore cable or in a conduit togethet the live conductoIs. I damage
721,544.1 Protective bonding conductors
tected bY Bchanical
721,544.1.1 The tenninations of protective bon
I
shall be accessible and protected agairst coffosio11.
,
:-.teLl als
721.55
Other equipment
721.55.1
ln
lets
72'1.55.1.1 Any AC electrical inlet on the caravan shall be an appliance inlet complying with ll interchangeability is required the inlet shall comply with BS EN 60309-2
BS EN 60309-1.
srrs t
721.55.1.2
(i) (ii) (iii) (i\)
The inict shall be installed:
not lnore thal l.ll nr above ground level, and in a readily acccssiblc position. and
suchthatit5hall haie a minimtun degree ofprotection oflP44 with or without a connector suchthalitshall not proflude significantly beyond the body olthe caravan.
engaged, and
721.55,2 Accessories 721.55.2.1 721
.55.2.2
Not u.sed
E\ cry sock{-outlet supplied at extra-low voltage shall have its voltage visibly marked.
721.55.2.3
Where an accessoly is located in a position in which it is exposed to the effects of moisture be constructed or cllclos.d so as to provide a degree ofprotection not less than 1P44.
it shall
721.55.2.4
Each luurinaire in a caravan shall prelerably be flxed directly to the skucture or lining ofthe caravan. Where a pendant lulri]raire is installed in a caravan, provision shall be made for securing the luminaire to prevent damage when tlre caravan is in rlotion.
Accessories fbr thc suspcnsion of pendant luminaires shall be suitable for the mass suspended and the forces associated with vehicle movelnent.
721.55.2.5 A luminaire 721.55-2.6
The rneans of connection to the caravan pitch socket-outlet shall be supplied with the caravan and
shall corrprise the ibllou
(i) (ii) (iii)
intended for dual voltage operation shall con.rply with the appropriate standard.
ilg
(see Figur-e 708):
A plug conplying witlr BS EN 60309-2. and a flexiblc cable ofcontinuous length 25 rn (+2 m), haying a harmonized code designation of H05RN-F or H07RN-F (BS EN 50525-2-21) or equivalent, incolporating a protective conductor, with conducton to be iclentificd accolding to Tabll: 5l and ofa cross-sectional area in accordance with Table 721. and a comector-.
TABLE 721
ifany. cornpatible with the appliance inlet inslalled under Regulation 721.55.1.
-
Minimum cross-sectional areas of flexible cables for caravan connection Ratcd cLlrrcnt
Minimum cross-sectional area mml
l6
2.5
25
4
32
6
63
16
r00
llcrn'c5oJ 6+E f;
310
urenmv
ANNEX A721 (lnformative)
GUIDANCE FOR EXTRA.LOW VOLTAGE DC INSTALLATIONS In genctal. the requirements ofSection 721 are also applicable to an extra-low voltage DC installation. The following requirenents should be applied in addition.
4721.31
Purposes, supplies and structure
4721.313 Supplies 4721.313,4 Sources of supply The supply should be obtained from one or more ofthe following sources:
(i) The electrical irstallation ofthe towing vehicle (ii) An auxiliary battery mounted in the caravar (iii) A low voltage DC supply via a transformerhectifier
unit complying
with BS EN 60335-l
and
I
BS EN 61558-2-6
(iv) {v)
A DC genemtor that is driven by any form of energy
I
Solar photoyoltaic (PV) power supply systems.
4721.5'14 ldentificationand notices
a:::;
4721.514.1 General 11e lollowing infbnnation should be provided in the instructions for use and should be in the tte country in which the camvan is to be sold:
(i) (iD
oficial language/s of
A wauring worded as follows: 'Any replacement of an auxiliary battery should be of the same type and specification as that origilally fitted' Instructions on the maintenance and recharging of an auxiliary battery where it is fitted. Where a battery charger is provided, instructions on its safe use should be included
(iii) Instructions on selecting and installing an auxiliary battery in a compafiment, ifthe caravar installation is designed for the installation ofan auxiliary battery Details of the waming notice specified in A721.55.3.7 and its impofiance for safety ln order to provide for sale operation of the electrical installation, a simplified diagram of the wiring of the ELV and LV ilstallation. with details ofthe cable colours and/or markins and the nominai values ofthe overcurent protectiye devices
(vi)
Type ofappliances that can be used and from what source ofsupply
(vii) lnstructions for the corect operation and maintenance of fitted appliances, as supplied by the appliance manufacturer
iriii)
Awarning worded
as follows: 'Always disconnect the elect cal connector between the towing vehicle and the calavan before connecting an LV supply to the caravan and before charging the caravan battery by any other mears.'
4721.515 Prevention of mutual detrimental influence 4721.515,2 The ELV instatlation should be so installed that the protective measures of the LV installation for rasic protection or for fault protectiol are not impaired. Ii should be verified that the protective conductors ofthe LV installation
are not loaded by the operating curents
.,lrhe ELV installarion.
A.72'1.52'l Types of wiring system 472'1.521.2
Cables should be ofstranded construction and should comply with B S 6004, BS 721 I or an appropriate
rart ofBS EN 50525.
472'1.523 Current-carrying capacities of cables 472'1.523,'l The cross-sectional erceeded.
*-
areas
ofthe fixed wiring should be such that the pennissible voltage drop is not
472'1.525 Voltage drop in consumers' installations Under normal service conditions the voltage at the teminals ofany fixed current-using equipment should be greater than the lower Iirnit conesponding to the British or Harmonized Standard relevant to the equipment. Where the equipmert is not the subject of a Blitish or Hannonized Standard, the voltage at the terminals should be such as not to impair the safc functioning ofthat equiprrent. In the absence ofprecise data a voltage drop of 0.8 V from the powef supply to the equiprlent may be allowed. The voltage drop betrveen the plug of the corulector to the towing vehicle or LV battery charger and the auxiliary battery should not exceed 0.3 V The charging current Ic (A) to detelnine the voltage drop is established by the following formula:
, c,0.1 rr--Jwhere:
I.
is the charying current in A
c is the battery capacity in Ah
t is the charging period in h.
NOTE:
Some batiery rnanufactur-crs now rate batterics in Watt/hours (Wh).
4721.528 Proximity of wiring systems to other services A7
21.528.2 Proxim ity to non -electrica I services
A.721.528.2.5 Cable runs and LPG installations Cables including those used for automotive purposes should not be nrn through a compartment or housing intended for liquefied petroleum gas storage cylinders. Where cables have to run through such a comparlment or housing, they should be run at a height of not less than 500 mm above the base ofthe cylinders, and such cables should be protected against mechanjcal damage by installation within a continuous gas tight conduit or duct passing through the compartment.
Where installed, this conduit or duct should be able to withstand an impact equivalent to AG3 without yisible physical dan.rage.
ELV cables and electrical equipment are only to be installed within the LPG cylinder compartment or housing if the installation serves thc operation of the gas cylinders (e.g. indication of empty gas cylinders) or is for use within the compartrnent or housing. Such clcctlical installations and components should be constructed and installed so that they are not a source of ignition and are jn accordance with the releyant standards for any hazardous area classifi cation of the conpartnlcnt or housitlg.
4721,53
Protection, isolation, switching, control and monitoring
472'1.533 Devices for protection against overcurrent A7 2'1.533.1
General requirements
4721.533.1.5 The overcurrent protective device for the power supply from the towing vehicle should be fitted as near as possible to the auxiliary battery, but in no case more than I 000 mm away. The overcurrent protective device for the auxiliaty battery should be fitted at the end of the battery cable and before the fixed installation. The ELV output of the transfonner/ rectifier unit and of the DC generator should be provided with an overcu[ent protective device installed as near as possible to the urit or generatol and, in all cases, upstream ofthe distribution circuits.
472'|,.533.1.6 Overcunent protective devices should be either fuse links according to lSO8820 or suitable cilcuit-breakers complying with BS EN60898-2. 4721
.533.1.7
Fuses should be protected to prevent accidental danlage.
4721.533.1.8 Overcu 'ent protective devices should not be fitted in a fuel storage compaftment or fuel storage housing intended for the stolage of liquelied petroleum gas (LPG) cylinders or in the compartment for housing an auxiliary battery.
312
A721.55 Otherequipment 4721.55.1 lnlets The inlet, when the plug is discomected, should be protected against the ingress of water, foreign bodies and accidental damage. A721
.55.2 Accessories
A721.55.2.6 The means olconnection
to the towing vehicle should be supplied with the caravan and comprise the
following:
(i) (ii) (iii)
Aplug complying with
BS
AUl49a and BS AU177a or BS EN
1SO11446. and
a flexible cable with the number ofcores with the minimum cross-sectional area and the allocation according to Table A72l and a length not exceeding 5 m, and
complying with BS AU149a and BS AU l77a or BS EN ISOI1446.
a connector
TABLE A721
-
Functional allocation and cross-sectional areas of cores for caravan connectors Contact numbers
Function
Core No.
BS AU 149a
BS EN ISO 1't446
directjon
indicator light
Minimumcross-sectional area mm2 t.5
I
I
Real lbg light
2
2
1.5
Courmorr retutrl fbr core Nos. 1.2 and 4 to 8
3*
3*
2.5
4
Right-hand directioD indicator light
4
4
I,5
5
Right-hand rear positior ard marker liglrts, and rear registration-plate illumination device
5
5
1.5
6
Stop lights
6
6
1.5
I
Left-hand rear position and marker lights, and rear registmtioll-plate illulrination device
'7
1
t.5
8
Reversirg 1igh1
8
1
1.5
9
Conti[uous power supply
9
4
2.5
i0
Power srpply coDtrolled by ignition switch
10
6
2.5
lt
Return for core
12
Coding for coupled trailer'
t2
2
I]
Return fbr core No. 9
13x
3*
2.5
t1
No allocation
5
1.5
I
Lefi-hand
2 3
BS AU 177a
No. l0
nx
2.5
* These rcturn circuits should not be connected electricallv in the trailer
A721.55.3 Auxiliary batteries A721.55.3.'l Type of battery
::::d l. der ice
EL\'
-{n auxiliary battery should be ofthe rechargeable type.
NOTE:
Non-rechargeable baticrics arc not auxiliary batteries. Thcy Dray be used in caravans, provided that thcy are used in circuits separatcd froln other sou!ces ofelectrical sripply.
A721.55.3.2 Capacity suitable
:::arASi '- .t:ug atl
\n auxiliarl battely should have a minimum capacity of40 Ah at 20 h disclralge mte. NOTE: lt is recon'unended to use a battery designed to be discharged over long pe ods at a relatively low
culTent.
A72'1.55.3.3 Terminals
.\uxiliary battery terminals should be clearly and durably marked
'+'
and
'-'.
Connectiols
to
auxiliary
battery tenninals should be securely clamped or bolted to provide continuous colrtact and should be jnsulated unless d1e auxiliary battely is provided with an insulating device.
A721.55.3.4 Location An auxiiiary battery
shor"rld be placed in a separate compafiment, with easy access for maintenance or removal, and sccurcd to prcvcnt rnovcmcnt ofthc battery, e.g. when the caravan is in motion.
A721.55.3.5 Auxiliary battery compartment A tlay should be installed under an auxiliary battery ifthe electrolyte of this battery is liquid. The tray should be sullicient to hold 20 % ofthe volume ofthe electrolyte.
The intcrior of an auxiliary battery compaftment should be ventilated and protected against the corrosive effect
of
acid-laden gases. either by:
(i)
irlstalling a scalcd auxiliarl battery that incorporates an extemal ventilating kit that is taken to the extedor ofthe caravan. or
(ii) installing an auxiliary battery in an enclosed battery compafiment that is protected intemally against corosion and is ventilated to the exterior of the caravan by means of a suitable hrbe with a minimum inside dianreter of l0 mm at the top of the auxiliary battery conpartment, in accordance with the battery lraflulirctuler's iustructions or as supplied by the manufacturer ofthe auxiliary battery or ( iii) ventilating the con'lpartrreflt at low level and high level to the exterior ofthe caravan and constructil]g the itrterior ol the conlpaftment, including the sides of the ve[tilator openings, ol acid-resistant matedal or providing it with an anticorrosive finish. If the compartment opens into the int€rior of the caravan, the lid should provide an air seal. The n.fnin.rum fi'ee area ofventilation should be not less than 80 mm: at low level and llot less t]ran 80 mmr at high level.
If
an auxiliary battery is not provided, then the position and instructions for the installation of the battery and conrpartmerlt. i11 accordance with (i), (ii) or (iii). should be included in the instructions for use and a notice should be lixed in or near thc proposcd location stating: 'For instructions on auxiliary battery installation, see the instructions for use'.
Thc lequircnents conccmillg tlle protection against corrosion and ventilation are not applicable
if
batteries with
bound electrolytes are used.
Where the maDlllilcturer rrakes no provision for the installation of an auxiliary battery the following statement should bc made in thc instnrctions for use: 'This caravan has not becn designr.d to accommodale an auxiliary battery. Do tlot lit otre.'
A721.55.3.6 Auxiliary battery cables Cables fr onr an ar.Lxiliary battery should be protected by additional sheathing or taping from the battery teminal up to ihe overcu ent plotective device.
A721.55.3.7 Warning notice A r.vanring notice should be llxcd in a prominent position near the auxiliary battery or displayed on the lid ol the auxiliary batterl cornpaftrnert. This waming should be in the official language(s) ofthe country in which the caravan is to be sold and should state: 'Switch
offall appliances
and lamps before disconnecting the auxiliary battery.'
The auriliary battery con'rpaftrrent should be additionally marked 'Smoking prohibited' BS 5499 aud
ir
in
accordance with
the larguage(s) ofthe country in which the caravan is to be sold.
A721.55.4 Other sources of supply A7 21.55.4.1
Generators and transformer/rectifier unit
If a suppll, is obtained tiom a generator or frorn a low voltage supply via a transformer/rectifier unit, the extralow voltage at tire outpnt termirals of the supply unit should be maintained between l1 V minimum and 14 V maximurr with applied loads varying tiom 0.5 A minirnum up to the maximum rcted load of the supply unit. Over the same load range. altemating voltage ripple should not exceed 1.2 V peak-to-peak. A721.55.4.2 Regenerative sources Regenerative enel€y sources. such as wind energy, solar energy etc., should be installed onty for charging batteries. Regenerative cner€y sources should only be operated with a device which prevents overcharging ofthe battery(ies).
314
SECTION 722 ELECTRIC VEHICLE CHARG!NG INSTALLATIONS NOTE:
Definitions relating to Section 722 can be found in Part 2 under electric vehicle (EV), {7221
722-1
.
Scope
The particular requirements ofthis section apply to circuits intended to supply electric vehicles for charging purposes.
The rcquirements olthis section do not apply to elect c vehicle charging points that:
(i) (ii)
enploy inductive charging
of l0 A and less.
charge mobility scooters and similal vehicles
NOTE:
Requirements 1br protection for safcty uhen feeding back electricity from an electric vehicle into a private or public
supply network arc undel considemtion.
722.3 722"31
Purposes, supplies and structure
722.3'11
Maximum demand and diversity
Assessment of general characteristics
A dedicated final circuit shall be provided for the connection to electric vehicles. It shall be considered that in normal use each single charging point is used at its mted current. Where the final circuit supplies more than one charging point no diversity shall bc allowed.
Diversity may be allowed for
a dcdicated
distribution circuit supplying multiple electric vehicle charging points
if
load control is available.
722.312 7
Conductor arrangement and system earthing
22.3'12.2.'l TN systems
For a TN system, the final circuit supplyirg a charging point for electric vehicles shall not include a PEN corductor
722.4 722.41
Protection for safety Protection against electric shock
722.410.3 General requirements 722.410,3,5 The protective measurcs ofobstaclcs 722,4110,3,6 The protective measures
of
and placing out ofreach (Section 417) shall not be used.
non-conducting location (Regulation 418.1) and eatlh-free local
equipotential bonding (Regulation 418.2) shall not be used.
722.4'l'1.4 TN system 722.411.4.1 A PME earthing l'acility shall rot be used as the means of earthing for the protective conductor contact of a charging point located outdoors or that might reasonably be expected to be used to charge a yehicle Iocated outdoors unless onc of thc lbllowing rnethods is used:
(i)
The charging point fom]s part ola three-phase irstallation that also supplies loads other than for electric vehicle charging and. because of the characteristics ofthe load of the installation, the maximum voltage between the main earthing tenninal ofthe installation and Earth in the event ofan open-circuit lault in the PEN conductor ofthe low voltage nefwoft supplying the installation does not exceed 70 V ITns. NOTE 1: Amrex 722. iterr A722.2 gives sorre infbrmation lelating to (i). NOTE
(ii)
2:
See also
Regulatioo 641.5 Nhen undenaking alterations and additions.
The main earrhing terminal ofthe installation is connected to an installation eatlh electrode by a protective conductor complying with Regulation 544.1. i . The resistance of the earth elecftode to Earth shall be such that the maximum voltage between the main eafthing terminal ofthe installation and Ea h in the event of an open-circuit fault in the PEN conductor of the low voltage network supplying the installation does not exceed 70 V nrs.
NOTE:
Anner
7ll.
iterr A722.3 gives guidance on detennining the maximum resistance required for the earth
(]lectrode in ( ii).
316
(iii)
''r'
Protection against elccttic shock is providcd by a der,ice rvhich disconnects rhe charging point lrom the live corlductor-s of the supply and fi'om protective eartl] ill accordancc with Regulation 543.3.3.10l(ii) within 5 s in the event ofthe voltage between the circuit protective conductor and Earth exceeding 70 V rms. The device shall not operate ifthe voltage exceeds 70 V rms for less than 4 s. The tlevice shall provide isolation. Closing or rcsetting ofthe device shall be by manual means only. Equivalent functionality could be included withil tlre chalging eqriiprnelt.
::ert bruied in thc ground, a protective conductor connecting to an earth electrode tbt the purposes
-.
i::r
e a cross-sectional area
'22.413
[ot
of(ii) or (iii)
less thal] that stated in Table 5,+.1.
Protectivemeasure:Electricalseparation
"n413 1.2 This protective tneasulc shall be limited to the supply of one electric vehicle supplied frorr.r '- -:i'i hcd source. The circLrit shall be supplied through a fixed isolating tralslbru complying with :' rl5-;8-l-4. " Selection and erection of equipment Common rules -, t
q1,1
Compliance with standards
'22 511.1 Wherc an EV charying poilt is built into a low voltage -- .-.:l1ler1ts ofthe relcvalt part ofBS EN 61439 ser.ies shall apply.
switchgear or controlgear assembly the
-22.511.101 EV charging equipment shall comply with the appropriate parts of the Bs EN 61gsi s e ries.
'22.512
Operational conditions and external influences
722.512.2 Externalinfluences 722.512.2.201 Presence of water (AD) t
Whcrc installed outdoors, thc cquipment shall be selcclcd with a degree ofprotection ofat least IPX4 in accor.dancc [N 60529 in order to protect against water splashes (AD4).
-.alor.
\\'ith BS
722.512.2.202 Presence of solid foreign bodies (AE) Where installed outdoors. the equipment shall be selected with a degree ofprotection ofat least lP4X in accordalce \\,ith BS EN 60529 to protect against the ingress of very small objects (AE3). L
722.5't2.2.203 lmpact (AG)
e local
: irtctor
Equipment instailed in public areas and car park sites shall be proteqted against mechanical damage (impact medium severity AG2). Protection ofthe equipment shall be afforded by one or morr ofthe following:
-
ihicle
.
:."-ctric i,llage -. i1'r the .
of
positiol or location shall be selected to avoid damage by atry reasonably foreseeable impact local or gereral mechanical protection shall be prcvided the
equipment shall be i[stalled that couplies with a minimum degree ofprotection against external mechanical impact of1K07 in accordance with the requireuents ofBS EN 62262.
722.531
Devices for fault protection by automatic disconnection of supply
722.531.2 RCDs 722.531.2.101 Except for circuits using the protective measure ofelectrical separation, each charging point shall ofat least Type A, having a mted residual operating cuffent not exceeding 30 nA.
be protected by its own RCD
::ecilve
:;
sucll
:-. et'tt
of
::'is nol :
:.i
.'artil
F*i
Each charging point incorporating a socket-outlet or vehicle connector complying with the BS EN 62196 series. protective measures against DC fault cunent shall be taken, except where provided by the EV charging equipl'l'tent. The appropriate measures, for each connection point, shall be as follows:
-
RCD Type B: or
RCD Type A and appropriate equipnrent that provides disconnection of the sLrpply in case of DC fault current above 6
rrA.
RCDs shall comply BS EN 62423,
NOTE:
lith
one ofthe following standards: BS EN 61008-1. BS EN 61009-1. BS
E\
60947-2 or
Rcquircments 1'ol lhe selection and erection of RCDs in the case ofsupplies using DC vehicle connectors according to the BS EN 62196 sclics are under considcration.
722.531.2.1.1 RCDs shall
722.533
disconnect all live conductors.
Devices for protection against overcurrent
722.533.10'l Each charging point shall be supplied individually by a final circuit protected by an overcunent protective device coflplyillg rvith BS EN 60947-2, BS EN 60947-6-2 or BS EN 61009-1 or with the relevant parts olthe BS EN 60898 series or the BS EN 60269 series. NOTE: The electlic vehicLe charling equipment rnay have multiple charging points.
722.537
lsolation and switching
722.537.4 Emergency switching off 722.537.4-101 Where en'iergency switching offis required, such devices shall be capable ofbreaking the full load cunent ofthc reler,ant parts ofthe installation and disconnect all live conductorc, including the neutral conductor
722.55
Other equipment
722.55.'101 Socket-outlets and conneclors
722.55.10'1.0.201.1
(i)
Each AC chargitg point shall incolporate:
onc sockct-outlet cornplying with B S i 363-2 marked 'EV' on its rear and, except where there is no possibility
of confusiolr. a labei shall be provided on the front face or adjacent to the socket-outlet or its enclosure staling: 'suitable fbr electric vehicle charging'. or
(ji)
ore socket-outlet or comector complying with BS EN 60309-2 which is interlocked and classified to clause 6.
(
iii)
L5 of BS EN 60309- I to prevent the socket contacts being live when accessible, or
one socket-outlct or corrr'rector complying with BS EN 60309-2 which is part ofan interlocked self-contained product complying with BS EN 603 09-4 and classified to clauses 6. 1 .l0l and 6.1. 102 to prevent the socket
contacts being lir'e uhen accessible, or (
iv) one Type i vehicle connector complying with BS EN 62196-2 for use with mode 3 charging only, or (v) one Type 2 sockct-outlet or vehicle connector complying with BS EN 62196-2 for use with mode 3 charging only. or
(vi)
l
I
one Type 3 sockclolrtlet or vehicle connector complying with BS EN 62196-2 for use with mode 3 charging
only.
NOTE:
Vthicle manuf'aclurers' instructions should bc followed when delerminjng the t)?e ofsocket outlet to be installed.
722.55.101.0.201.2
Each socket-outlet shall be installed in a distribution board in accordance with Regulation 722.51 or in its appropdate enclosure (e.g. flush or surface mounted socket-outlet box) and mounted in a fixed position. Poftable socket-or.rtlets shall not be used but tethered vehicle connectors are allowed.
722.55.101 .3 One socket-outlet or vehicle connector shall supply only one electric vehicle.
722.55.101.4ln EV charging modes 3 and 4, an electrical or mechanical system shall
be provided to prevent the plugging/unplugging of the plug un)ess the socket-outlet or the vehicle connector has been switched off fron.r the
supply.
722.55.1 01 .5 The lowest paft of any socketoutlet shall be placed at
NOTE:
a
height of 0.5 to I .5 m from the ground.
The rcquirements of the relevarlt National Building Regulations should be adhered to in respect of socket-outlet heights.
722.55.101.6 Precautions on supply of the fixed installation by the EV NOTE:
318
ReqLrilements f'or precautions on supply ofthe fixed jnstallation by the
Ev
are under consideration.
\:. \:.
ANNEX A722 (lnformative)
GUIDANCE FOR TN SYSTEMS WHERE PME CONDITIONS APPLY NOTE:
A list ofdre symbols used in this Annex is given in item A722.4.
A.722.1
Neutral current of a three-phase installation
Where the power factors ofthe currents in all three phases are similar and triple harmonics can be neglected, it may be assumed that the neutal cunent ofa three-phase installation is given by:
NOTE:
The rnaxirrum nelrtml current (Im) occurs under conditions of maximum irnbalance, not necessarily maximum overall demaod.
4722.2 Load balance Where t ple harnronics can be neglected,
condition (i) of Regulatron 722.411.4.l may be assumed to apply where
the following condition is met.
I ^II^ -rL -U
Ilrl;rl;' 4722.3
/u
Earth electrode resistance
For the purposes ofcondition (ii) of Regdal;1on722.411.4.1, the sum olthe resistances ofthe eafih electrode and the protective conductor connecting it to the main eafihing teminal must meet the following condition, as applicable. For a single phase installation:
D
'' \.,
70
-
t 1.,
----------------
'
1,,,,,
(Ur
7())
For a thrce-phase installation:
:: l'r{
10
1
R.q
I,,,-
"u
::::lg
ltir iu
(ILl + ILz + ILr)
The above tJrree-phase forrnula tbr RA ev is valid only where I," > ua I (ILl + IL2 + IL3) . Where this is not the case. this indicates that condition (i) of Regulation'722.411.4.1 applies and that an earth electode is not required for the purposes of condition (ii) of tlrat regulation.
NOTE:
-::i"
fi
x
A.722.4
Symbols used in this Annex is the rms maximum demand curent ola single-phase installation (in amperes), including that ofthe electric vehicle charging load and any other loads, determined in accordance
I,,,"
with Regulation 3l
is the 1.1r1s maximum neutral current ofa three-phase installation (in amperes), including that ofthe electric vehicle charging load and any other loads, determined in accordance with Regulation 311.1.
I,,,
,::.:
:
the
::' ihe
Il,
1.1.
Ir
r and Ir r
are the rms values
ofcurent (in amperes) in lines 1,2 and 3, respectively, that were
when detemining the value of RA",
is the sum
ofthe
resistances
ofthe earth electrode and the prolective colductor connecting
it to the main earthing teflninal of the installation (in oh[]s), in
!::-- 'lili: u{r
used
1,,,
iter.i,
A722.3.
is the nominal AC rms line voltage to Earth.
NOTE 1: The above curents and voltage are magnltudes onlyi they are not phasors. NOTE 2: In detennining charging points.
I,,,. Ir L.
Irr and
11;,
allowance must be nrade for single-phase vehicles being charged from three-phase
SEGTION 729 OPERATING AND MAINTENANCE GANGWAYS Scope
729.1
the operation or to basic protection and other aspects relating to The particular requirements of this section apply to skilled restricted is access whire gangways, areas including maintenance of switchgear and controlgear within or instructed Person(s).
Assessment of general characteristics For restricted access areas the following apply: (i) They shall be clearty and visibly marked by appropriate signs
(ii)
They shall not provide access to unauthorised persons
(iii)Doorsprovidedlbrclosedlestrictedaccessareasshallalloweasyevacuationbyopeningwithouttheuseof '"-' t"v, i"or - any other device not being pafi of the opening mechanism' "
729.513 Accessibility gangways 72g.513.2 Requirements for operating and maintenance for work' opemtional access' emergency access' The width of gangways and access ateas shall be adequate emergency evacuation and for tlansport ofequipment' Gaugwaysshallpermitatleastag0degreeopeningofequipmentdoorsorhingedpanels(seealsoAn-rrex4729).
729.513.2.1 Restricted access areas where basic protection is provided by barriers or
enclosures
\\
here basic protection is proi ided bv baniers or enclosures in accordance with Chapter 41. the following minimLurr dintelsions apply (sce Figure 719.1 ):
(i)
Gangway width including between:
700 mn.r
balriers or enclosures and switch handles or circuit-breakers in the most onerous position, and
baniers or enclosules or switch handles or circuiGbreakers in the most onerous position and the wall
I
(ii)
Cangway width between barriers or enclosures or othel barriers or enclosures and the wall
(iii)
Hcight ofgangway to ban ier or enclosure above floor
(iv
Live parts placed out olreach. see Regulation 417.3
NOTE:
)
700 urn.r
um 2500 nnr 2000
Where additional workspace is needed e.g. for special switchgear and controlgear assemblies. larger dimensions
nay
be required.
Fig 729,'l
-
Gangways in installations with protection by barriers or enclosures
Barrier or enclosure
-r--
-t I
I
I
I
I
'
Barriers or enclosures
1
t/ (\
\
---1 I I I
I
I
I
I
I
lCircuilbreaker
rl
I
I (iv) Reg 417.3
lin the position I
";soiation" It
I
l
(iil) 2000 mml
I
r
I I I I I I
(ii) 700 mrn
I{OTE:
-.*r*_-
(ii) 700 mm
(i) 700 mm
(i) 700 mm
The above dlntensions apply atier bao-iers and enclosurcs have been fixed and with circuit-breakers and switch handles in the most onerous position, including "isolation".
321
729.513.2.2 Restricted access areas where the protective measure of obstacles is applied Wherc the protecti!e l'neasulc of obstacles is used, the requiren.rents of Section 417, Obstacles and placing out of reach, apply. The meastLre is tbt applicatio[ ir] those pa s ofinstallations controlled or supervisedby skilledpersons. The following miniruurr ditnetrsious apply (see Figute 729.2): 700 InnI
(D Cangrvay rvidth including between:
obstacles and switch handles position, and
or cilcuit-breaken in the nost
onerous
obstacles or switch handles or circuit-breakers in the most onerous position and the wall. (ii
)
700 trm
Cangway width betweel obstacles ol other obstacles and the wall
2000 mm
(iii) Height ofgangway to obstacles above floot' (iv )
2500 mrn
Live parts placcd out ofrcach, see Regulation 417.3
Fig 729.2
-
Gangways in installations with protection by obstacles
Obstac es
parts
-1- -'i I I I
I
i-
'l/\f
t / II
\r\t
---1 t t
i
I
I
I
I
I
I
I
I
(iv)Reg 417
(il) 2000 mml I
I I I I
I
NOTE:
The above clinensions apply after all obstacles have been fixed and with circuit-breakers afld switch hand]es in most onerous position, including'isolation".
729.513.2.3 Access to gangways Gangways lolger tltan l0 rn shall be accessible from both ends.
NOTEl:ThisrnaybeaccomplishedbyplacementoftheequipmentamininrurnofT00mrnfromallwalls(seeFi;::.---:: by providing an access door, ifneeded. on the r.all against which fte equipment is positioned.
Closed rest cted access ateas with a length exceeding 20 rn shall be accessible by doors from both enci. NOTE 2: For closed restrictcd access areas wilh
Fig 729.3
-
a
length cxceeding 6 m, acccssibility from both ends is recommer;.:
Examples of positioning of doors in closed restricted access areas
> 700 mm
Gangway length does not exceed 10 m within the closed restricted access area
I Gangway length exceeds 10 m within the closed restricted access area, whose length does not exceed 20 m
Gangway length exceeds 10 m within the closed restricted access area, whose length exceeds 20 m
Doors giving access to gaugways shall open outwards (see Figure 729.3) and they shall have the following minimum imens ions:
J
(i) (ii)
width 700 mm height 2000 nrl.r.
ANNEX A729
(Normative) ADDIT]ONAL REQUIREMENTS FOR CLOSED RESTRICTED
ACCESS AREAS A729.1 Evacuation For reason of easy evacuation the doors of any equipment inside the location shall close in the direction of the evacuation route (see Figure 4729.1). Gangways shall pemit at least a 90 degree opening of equipment doors or hinged panels (see Ftgure A729.2).
Fig 4729.1- Minimum passing width in case of evacuation
-
Case
1
/////t//t/////////////////////// Evacuation route direction -------->
I 2
Circuir-brcakcr in the isolaled posilion Handles (e.g. for contrcls or eqlripment)
In the
case of doors which can be fixed in the open position and circuit-breakers which are withdmwn fully for maintenance (completely extracted) a ninimunr distance of500 nrrn shall be complied with between the door edge or circuit-breaker/ equipment edge and the opposite limitation ofthe gangway (see Figure A729.2).
- Minimum passing width in case of evacuation - Case 2 .////////////////////t////t///f//ffi
Fig 4729.2
,^
passrnq
mrnrmum
width 5OO
mm' ----f,-
I
II
Evacuation route di.ection _________>
I
Circuitbreakcr ir thc positiou _colnpletely extracted" Fixing device of
a
door
The ninimunl u.idth gaDgway of500 nnn shall be taken into consideratioD bctwccn the wall and the circuilbreaker in the position "complelely exlracted'and equipmcDt door iD thc 90 degree position.
324
SEGTION 730 ONSHORE UNITS OF ELECTRICAL SHORE CONNECTIONS FOR
INLAND NAVIGATION VESSELS 730.1
Scope
na\ igation The par-ticuiar requirements ofthis sectio11 apply to onshole installations dedicated to the supply of inland .,"rril, fo, .on r"tcial and administrative putposes, berthed in ports and berhs NOTE 1: For supplies to pleasure craft or houseboats in marinas and sirnilar locatiolrs. see sectio[ 709.
This section applies to installations with nominal supply vo)tages not exceeding 230 AC three-phase. NOTE 2: Additional
r.eclLLiremenrs that do not relate
v AC
single-phase and '100 V
to electrical installatioi are given in BS EN 15369-l aud BS EN 15869-2'
including their The particular requirements do not apply to the onboard installations of inla1ld navigation vessels 15869-3' connection cables. Additional requircn.rerlts on the onboard installation ale giver in BS EN
730.31
Purposes, supplies and structure
730.312 730.313
Conductor arrangement and system earthing Supplies
730.313.1.101 The nominal supply voltage shall be 400 V three-phase AC' 50 Hz. NOTE: An alrangement diagraD ofan elect cal shore connectio[ is shown in BS EN I5869-1.
and an overvicu diagran
of
an electrical power-supply statiol with two connector units is shown in BS EN 15869-2'
730.313.1.102 Galvanic separation the hull olthe Where a fixed onshore isolating transfomer is used to prevent galvanic currents circulating betweel] be used. shall EN 61558-2-4 ressel and metallic parts on the shore sidc. equipment complying with BS
'' lr
to the eadh tenrinal The protective conductor (PE) ofthe supply to the isolating transfonner shall not be connected in the socket-outlet supplying the inland navigation vessel.
730.4 Protection for safety 730.41 Protection against electric shock 730.410.3.5 The protective measurcs ofobstacles and placing out ofreach (section 417) shall not be used. 730.410.3.6 Tire protective measures of norl-conducting location (Regulation 418.1) and earth-frce local cquipotential bording (Regulation 418.2) shall not be used.
730.411.4 TN system earthing The Electricity Safety, Quality and Continuity Regulations (ESQCR) prohibit the connectiorl of a PME iacility to any metalwork in a boat. puryoses, such as to the This does not preclude the use ofa PME earthing facility as the means ofealthing for othel installat ions of perntanenl buildirlgc.
NOTE:
Thc requirenlenis ofother sections ofPart 7 may also apply.
730.5
730.512
Selection and erection of equipment Operational conditions and external influences
730.512.2 External influences 730.512.2.101 Degree of protection Equipmert shall be selected with a minimum degree ofprotection oflP44'
730.521
Types of wiring system
730.521.10'l Wiring systems of berths, ports and floating landing stages 730.521.101.1 Berths and ports The following wi|ing systems and cables are suitable for distributiorl circuits in berths and ports;
(i) (ii) (iii)
uuderground cables overhead cables cables with copper conductors and thelmoplastic or elastomeric insulation and installed within an appropt iate cable Inanagement system taking into account external inflLrences such as movement, ilnpact, corlosion and
ambie[t tenlPerature
(iv) (v)
mineral-iusulated cables with thennoplastic protective covedng am]oured cabtes with a thetmoplastic or elastomeric covering.
Other cables and rlaterials that are at least as suitable as those listed above may be used.
730.521.10'1.2 Floating landing stages Widng systelns and cables shall be suitable tbr the movement of floating landing stages. The lbllowing wiring systems and cables are suitable for distribution circuits on floating landilg stages:
(i)
cables with copper conductors and theunoplastic or elastomeric insulation and installed within an appropriate cable management system taking into account extemal influences such as movement, ilrpact, conosion and
ambient tempel.ature
(ii)
ar[rouled cables witl]
a
thermoplastic or elastomeric cove ng.
Other cables and materials that are at least as suitable as those listed in (i) or (ii) may be used
730.521.'101.3 Cables and cable management systems 730.521.101 .3.1
General
Cables antl cable management systcnrs :llall be selected and installcd so that Ileciranical damage clue to tidal and olher movement ol floating slructltres is prevented. Cable management systcns shall be illstalled to allorv thc dlainage of water/condcltsate. e.g. by sloping au'ay and/ ol drainagc holcs.
730.521.101 .3.2
Underground cables
Undergrounrl distribution circuits shall, unless provided with additional mechanical protection, be buried at a sutEcient depth to avoid being damaged, e.g. by movement ofvehicles. NOTE 'l: A depth of 0.6 m is geDerally considercd as a rninimum dcpth to f'ul1il this requirement. NOTE 2: For corldlrit systems buried underground, see BS EN 61386-24.
730.521.101.3.3
Overhead cables
Ovelhead cables shall not be used over waterways. poles and other supports for overhead wiring shall be located or protected so that they are unlikely to be damaged
by any tbr-eseeable movement ofvehicles.
I
Overhead cables shall be at a height above ground ofnot less than 6 m in all areas subjected to movement ofvehicles and 3.5 m in all other areas.
Ary ovcrhead conductols shall bc insulated.
730.53
Protection, isolation, switching, control and monitoring
730.531
Devices for protection against electric shock by automatic disconnection of supply
730.531.3 Residual current protective devices
(RCDS)
Sockeloutlets wirlr a rated curent not exceeding 63 A shallbe individually protected by an RCD providing additional protection in accordance $ irh Regulation 415.I having a rated residual opelating cut rent llot excecding 30 mA.
--
326
Thc RCD selected shall discouuect all li\ e conductols, i e' line and neutrel'
-:'::''-rerllnotcrceedinuluorllA.ThcRtDsclecrc'l'hclldi'cotlne'lrll"'J::---'--'-:'-:-'
Sockeloutletswitharaledcuflerltexceeding63Ashallbeindividualllptotec::;:'::-]-'::' opelatingu
NOTE:ThepurloseoftheseRCDSisiopr-otecttheshoresupplyandtheflexible"hleli'::---':'-':-::i:r:r' 1br onboard
730.533
cilcuits, which are oLttside the scope ofthis sectior'
Devices for protection against overcurrent
prolective device' Socket-outlets shall be individLrally prolected by crl o!ercurrcnt
730.537
lsolation and switching
730.537,2 Devices for isolation distbution boald, ThiS derice shall 730,537,2,1 At least one means of isolation slrall be installed for each disconnect al1 live corductors.
730.55
Other equipment
730.55.1 Socket-outlets 730.55.1.1Socket-outletsslrallcorrrplywithBSEN6030g-1andBSEN60309-4andSocket-outletswitha curaent ruting not exceeding 125 A sha1l comply u'ith BS EN 60309-2
EN 60309-1 and BS EN 60309-4 and \vhere irlterchaDgeability is not required. socket-outlets shall cornply with BS need not con.tply u'ith BS EN 60309-2.
730.55.1.2
to be supplied Socket-outlets shall be located as close as practicable to the befih
730.55.1.3
No more than four sockct-outlets shall be grouped togethcr in any one enclosure
730.55.1.4
Each sockcroutlet shall supply only one vesscl'
730.55.1.6
l51169-2 Sockeroutlcts shall bc placed in an enclosurc iu accordance with BS EN
730.553,13Socket-outlctsshallbcplacedataheightofnotlessthanlmabovethehighestwaterlevel.Inthe to 0 3 m above the highest water level -:.e of floating pontoons or talkways oniy, this height may be rcduced .
the ef1'ects of splashing' :.,r ided that a]rpropriate aclditional mcasures are laker to protcct against
s-pp,
f,-l
ANNEX A73O
(lnformative) Examples of methods of obtaining supply ln Figures A730.I
to A730..1,
Fig A730.1
Shore
Overcurrent protective device
-
fullctional switches are not shown.
Direct connection to a single-phase mains supply
Vessel
RCD
N o_' PE
To metallic parts in contact with
water surrounding the vessel
There is a risk ofelectrolytic corrosion resulting frofir circulating galvanic currents in the protective conductor to shore.
Fig A730.2
-
Direct connection to a single-phase mains supply with an isolating transformer on the vessel
Overcurrent Shore
Vessel
protective
device RCD r o-1- --fl-----<
Il N*HlPE
o
,-<
To metallic parts in contact with
water surrounding the vessel
No connection shall be n.rade between the PE conductor of the vessel and the PE conductor of the shore supply (see Regulation 730.313.1. 102). This is ro prevent galvaric cunents circulating between the hull ofthe vessel and metallic parts on the shore side.
Fig 4730.3
-
Direct connection to a three-phase mains supply
Shore
Overcurrent protective device
RCD L1
L1
L2
Flexible cable five cores
L2
L3
L3 N
N
PE
To metallic parts in contact with
water surrounding the vessel
There is a risk olelectrolytic corosion resulting fiom circulating galvanic currents in the prctective conductor to shore.
Fig A730.4
Overcurrent ' :!1
protective
device
-
Direct connection to a three-phase mains supply with an isolating transformer on the vessel
S
hore
RCD
RCD 1,1
on L2 L3 N
To metallic parts in contact with water surrounding the vessel
No connection shall be made between the PE conductor of the vessel and the PE conductor of the shore supply (see Regulation 730.313.1.102). This is to prevent galvanic currents circulatirg between the hull ofthe vessel and metallic pafts on the shore side.
:: Jith
...rPl.v
... .itld
SECTION 740 TEMPORARY ELECTRICAL INSTALLATIONS FOR STRUCTURES,
AMUSEMENT DEVICES AND BOOTHS AT FAIRGROUNDS, AMUSEMENT PARKS AND CIRCUSES
740.1 Scope, object and fundamental principles 740.1.'l Scope This section speciies the nrinimul1r elcctrical installation requirements to f'acilitate the safe design, installation and operatiou of temporarily erected mobile or transportable electrical machines and stuctures which incorpomte electrical equipmelt. The nachines and structures ale intended to be installed lepeatedly, without loss of safety, temporalily, at l'airgrounds, al'[usement parks, circuses or similar places. The object ofthis section is to define the clectrical installation requiLements for such structures and machines, being either integml parts or constituting the total amusement device.
This section does not apply to the intenral electrical wiring ofmachines (see BS EN 60204-l). NOTE 1: Guidance on temporary electical systems lbr entertainment and related pluposes is givcn in BS 7909. NOTE 2: The permancnt electrical installation is excluded from the scope.
740.3 740.3'l 740.313
Assessment of general characteristics Purposes, supplies and structure Supplies
740.313.1 .'1 Voltage The non.rinal supply voltage of temporary elect cal installations in booths, stands and amusement devices shall not exceed 230/400 V AC ot 440 V DC.
740.313.3 Supply from the public network Irespective oftlte number of sources of supply, the line and neutral conductols tiom dift'erent sources shall not be interconnected downstream ofthe origin ofthe temporary electrical installation. The instmctions ofthe opemtor for the supply ofthe systen to the public shall be followed.
740.4 740.41
Protection for safety Protection against electric shock
740.410.3 General requirements Automatic disconncction of supply to the temporary clectrical installation shall be provided at the origin of the ilstallation by one 01 more RCDS with a rated residual operating current not exceeding 300 [rA. The RCD shalf incotpolate a time delay in accordance with BS EN 6094'7 -2 or be of the type S ir accordance with BS EN 61008-l or BS EN 61009-l where necessary to provide selectivity with RCDs protecting final circuits.
740.410.3.5 The protective
rneasure ofobstacles (Regulation 417.2) shall not be used.
Placing out of arn's reach is acceptable for elect c dodgerrs (see Regulation 740.55.9).
740.410.3.6 The protective measures of non-conducting location (Regulation 418.1) and earth-free local equipotential bolding (Regulation 418.2) shall not be used.
740.4'11
Protective measure: Automatic disconnection of supply
NOTE; For
supplies to
AC
motors. RCDS. where used, should be of the time-delayed type in accordaDce with ir accordance with BS EN 61008-1 or BS EN 61009-1 where necessary to prevert
BS EN 60947-2 or bc ofthe type S
urt$dnlcJ
330
lripll
,y.
740.41'1.4 TN system 740.411.4.1 A PME eallhing facility shali not be used as the means of earthing for an installation falling s ithin oflhis section. NOTE: The Electricity Safety, Quality arld Continuity Regulations (ESQCR) prohibit the use ofa PME earthing facilir] as the
the scope
means ofealthing for thc iistallation
ofa calavan or silnilar coustruction-
740.411.4.3 Where the type of systerr earthilg is TN, a PEN conductor shall not be used downstream of the origin of the temporary electrical installation.
740.411.6
IT system
Where an altemative system is available, ar 1T system shall not be used. IT systems, howeveq may be used for DC applicatiols where continuity of service is needed.
740.415 Additionalprotection 740.415.1 Additional protection:
RCDS
All final circuits for:
(i) (ii) (iii)
lighting, socket-outlets rated up to 32 A, and
mobile equiprnent connected by means ofa flexible cable with a cunent-canying capacity up to 32 A
shall be protected by RCDs having the characteristics specified in Regulation 415.1.1.
NOTE: The requirement fbr additional protectior't relates to the increased risk of
damage to cables.
The supply to a battery-operated emergency lighting circuit shall be connected to the same RCD protecting the lighting circuit. This requirement does not apply to:
(iv) (v) (vi)
circuits protected by SELV or PELV, or circuits protected by electuical separation, or
lighting circuits placed out of alm's reach, provided they are not supplied by socket-outlets for household or similar purposes or socket-outlets accordirg to BS EN 60309-
l
.
740,415,2 Additional protection: Supplementary protective equipotential bonding 740,415,2,1 In locations intended for livestock, supplementary bonding shall connect all exposed-conductiveparts and extraneous-conductive-par1s that can be touched by livestock. Where a metal gdd is laid in the floor, it shall be included within the supplementary bonding ofthe location (seeFigure 705). E\traleous-conductive-parts in, or on, the floor, e.g. concrete reinforcement in general or reinforcement of cellars lbr liquid [ranure, shall be connected to the supplen]entary protective equipotential bonding.
It is recommended that spaced floors made ofprefabricated concrete elements be part ofthe equipotential bonding ,
see
Figure 705). The supplementary protective equipotential bonding and the metal grid, if any, shall be erected so
-hat it is durably protected against mechanical stresses and corrosion.
740,42
Protection against thermal effects
740.422.3 Nature of processed or stored materials 740.422.3.7 A motor which is automatically or remotely controlled and which is not continuously supervised ihall be fitted witll a manually reset plotective device against excess tempemture.
740.5
Selection and erection of equipment
740.51
Common rules
itchgear and controlgear shall be placed in cabinets which can be opened only by the use of a key or a tool, for those parts designed and intended to be operated by ordinary persons (BAl) as defined in Part 2 (see also =a.ept S;r
{ppendix 5).
--*-r
i
740.5'12
Operational conditions and external influences
740.512.2 External influences Electrical equipment shall have a degree ofprotcction ofat least IP44.
740.52
Wiring systems
740.521
Types of wiring system
740.521.1 Cables and cable management systems Conduit systems shall comply with the relevant part ofthe BS EN 61386 series, cable trunkirg systems and cable ducting systems shall comply widr the relevant part 2 of BS EN 50085, and tray and ladder systems shall comply wittr BS EN 61537.
All cables shall meet the requirements ofBS EN 60332-l-2. Cables shall have a minimum rated vo)tage of 450/750 minimum rated voltage of300/500 V may be used.
V
except that, within amusement devices, cables having a
The routes of cables buried in the ground shall be maked at suitable intervals. Buded cables shall be protected against mechanical damage. NOTE 1: Conduit classifled as 450 N regarding protection against compressiol and classified as nonnal regardilg protectio]1 against impact. accordilg to BS EN 61386-24. is corsidered to fuIfl] the above requirement.
Armoured cables or cables protected against mechanical damage shall be used wherever there is a risk ofmechanical damage due to extemal influence, e.g. > AG2. Mechanical protection shall be used in public areas and in areas where wiring systems are crossing roads or walkways. The following frethods are consider-ed to meel the above requiren]ents:
(i)
conduit systems conplying with B S EN 613 86-2 1 with a classiflcation of heavy regarding protection against compression, a classificatior ofheavy regarding protection against impact, and, for metallic and composite colduit systems, class 3 protectiol against corosion (i.e. mediun protection iuside and high protection outside)
(ii)
cable trunking systems and cable ducting systems con'rplying with BS EN 50085 series with a classification 5 J regarding proteclion against irnpact.
Where subjected to nrovement, wiring systems shall be offlexible construction. Where flexible conduit systems are provided they shall comply with BS EN 61386-23. NOTE 2: Cables oftype H07RN-F oI H078N.l-F (BS EN 50525-2-21) together with conduit complying with BS EN 61386-23 are deerned lu sctisfy this requirelncnt.
740.526
Electricalconnections
Joints shal1 not be made in cables except whele neccssary as a connection into a circuit. Where joints are nrade, these shall either use connectors in accordance with the relevant British or Harmonized Standard or the connection shall be made in an enclosure with a degree ofprotection ofat least IPXXD or IP4X. Where strain can be traNmitted to
te rinals the connection shall incorporate cable anchorage(s).
740.53
Switchgear and controlgear
740.537
lsolation and switching
740.537.1 General Every electrical installation ofa booth, stand or amuscment device shall have its own means ofisolation, switching and overcufient protection. which shall be rcadily accessible.
740.537.2.1.1 Every
separate temporary electrical installation
for amusement devices and cach dist bution
circuit supplying outdoor installations shall be provided with its own readily accessible and properly identified means ofisolation.
332
7
40.537.2.2
Devices for isolation
A device tbr isolation shall discotrnect all live conductors (line and neutral conductors).
740.55
Other equipment
740.55.1 Lightinginstallation
"
Luminaires ald be decorative lighting chain shall be installed so as not to impail its ingress ptotection' cable' the supply by canied llot be shall weight it' lts camy to intended -- :i to the stlucture o[ supPoft putpose. this lbr - .::-. .;lected atld erected
-irr:
,1nd
j3.-!)r'atile lighting cltains mounted less than 2.5 m (artn's reach) above flool level or otherrvise prevent t isk of injury to persons or . - , c:nral contaJt. shall bc firmly fixed ald so sited or guardcd as to only be possible after removing a ban ier or an enclosure -: i .:. !. \ccess to the fi xed light source shall re,luire the use ofa tool.
-:
-...,ll
Lrse
H05RN-F oI HOTRN-F (BS EN 50525-2-21) cable or equivalent
....:''ln.nral'betlsedilla0ylengthprovidedthcovelcu[cntprotecti\ede\iceinthecircuitisplopcrlyr.ated. La m
pholders
.-- = rmpholders shall not be used unless the cables and lanlpltolders '- :: r:nrovable ol1ce lltled to the cable.
ale compatible and the
Lamps in shooting galleries
.
:
::: galleries and other sideshows wherc projectiles
are used shall be suitably protected against
= ood lights
j
;
cables ',,.rtllights are uscd. thcy shall be mounted so that tlle luniilairc is inaccessible Supply
r:.,\.
adequate prolcction against mechanical danage'
re risks from luminaires and floodlights
of hcat is not likcly to alrd flooiJliglrts shall bc so tlxed and protected that a focusing ol. collcentlatio)l
---.r
ignition olanY material.
740.55.3 Electricdischargelampinstallations stald oI amusement device witi'l an opelating voltage -tstallations of any lurinous tube. sign or lamp on a booth, :igher than 230/4ti0 V AC shall colrply with Regulations 740 55 3 1 and 740 55 3 2' ..--:. tfiest -:.-,1 shall
740.55.3.1 Location adequately protected to reduce the risk The luminous tube. sign ol lamp shalt be installed out of arm's teach ot be .)l injury to Persors.
740.55.3.2 Emergency switching device which shall bc controlled by all emelgel]c) -\ separate circuit shall be used to supply luminous tubes, signs or lamps, with the requiremetlts of the locai srvitch. The switch shall be easily visiblc, accessible and marked in accordance audrotity.
740-55.5 -. . r itching
Safety isolating transformers and electronic convertors
provide an equivalent degree of safety' Safcty isolating transformer s shall comply with BS EN 61 558-2-6 or oI electrol'lic conveftol' A nlanually reset pl.otective dcvice shall protect the secondary circuit of eacl] transfbnler
:.:ir ibution
l.
:dentified
Saletyisolatirrgtransfonrrersandelectro],licconveltorsslrallbetlountedoutofanll.steachorbenrountedil,ia
that can only be acccssed to.ution thnt piviacs equal protcctiol1. e.g. in a panel or room with adequate \ entilatioD
fry
,tiff.J
testing and maintenarlce o, i,.,u,.,,.t.d p"..onr. Such acceis shali be provided only to facilitate inspection.
Electlol'ric col'tvetlors shall confonn to BS EN 61347-2-2'
I
Enclosules containing rectiliers and tansformers shall be adequately ventilated and the vents shall not be obstructed
when in use.
740,55.7 Al
Plugs and socket-outlets
adequate number of socket-outlets shall be installed to a)low the user requirements to be met safely.
NOTE
1
:
1n
booths, stands and for fixed installations, onc socket outlet fol cach square metre or lincar rnetre of wall is gencrally
considered adcquate.
Socket-outlets dedicated to lighting circuits placed out of arm's reach (in accordance with Regulation 140.415.1) shall be encoded or rnalked according to their purpose. When used outdoors, plugs, socket-ontlets and couplers shall comply with:
(0 (ii)
BS EN 60309-2, or
whele interchar, geability is not required, BS EN 60309-1.
However, sockeloutlets according to the relevant National Standard may also be installed if they have suitable mechanical protection (equivalert to the reqlrirements ofBS EN 60309-l) and a mted current not exceeding 16 A. NOTE 2: Suitable meohanical protection may be provided by the socket-outlet or by an enclosure.
740.55.8 Electricalsupply At
each amusetnent device, there shall be a corxrectiou point r-eadily accessible and permanently marked to indicate the following essentiai chamoteristics:
(i) (ii) (iii)
Rated voltage Rated cuncnt Rated li'equency.
740.55.9 Electricdodgems Electlic dodgems shall otrly be operated at voltages not exceeding 50 V AC or' 120 V DC. The circuit shall be electrically separated from the supply mains by rneans ofa transfoflner in accordance with BS EN 61558-2-4 or a motor-generator set.
740.551
Low voltage generating sets
740.551.8
cenerators
A1l generators shall be so located or protected as to prevent danger and with hot surfaces and dalgerous pafts.
iljuly
to people through inadverlent contact
Electrical equipment associated with the generator shall be mounted securely and,
if
necessay, on anti-vibrution
nountings. Where a gel]erator supplies a temporary installation, forming paft of a TN, TT or lT system, care shall be takel to velify that the ealthing arrangeurelts are in accordance with Regulation 542.1 and, where eafth electlodes are used. with Regulation 542.2. The neutral couductor olthe star-point ofthe generctor shall, except for an IT system, be connected to the exposedconductive-parts of the genemtor. 7
lnspection and testing
40.6
'l'he electdcal installatjoo between its origin and auy electrical equipment shall be inspected and tested in accordance with the requitements of Part 6 afier each assembly on site. NOTE
'l
: Intelnal elecl cal wiring of roller coasters. electric dodgerrs and similar equipment are not considered as part of the
verificalion NOTE 2: In special cases the rurrbcr ofthe tests may be modified according to the type oftemporary clectrical installatron.
I
SECTION 753 HEATING CABLES AND EMBEDDED HEATING SYSTEMS Siope
753.1
This section applies to ernbedded electric heating systems for surface heating. It also applies to electric heating systems for de-icir'rg, frost preyention and siniilar applications. Both indoor and outdoor systems are covered.
.
Heating systerns for indust al and cornmercial applications complying with relevant parts olBS EN 60519, BS EN 62395 and BS EN 60079 are not covered.
.l
NOTE:
Examples ofheating systems covered by thjs Standard are heating systems forwalls, ceilings, floors, roofs, drainpipes, gutters. pipes, stairs, roadways. and non-hardened compacted arcas (e.g. football fields, lawns).
753.4
Protection for safety
753.41
Protection against electric shock
I
753.410.3 Generalrequirements 753.410.3.5 The protective measures ofobstacles and placing out ofreach (Section 417) shall not be used.
I
753,410.3.6 The protective measures of non-conducting location (Regulation 418.1) and eafih-free local -...te
equipotential bonding (Regulation 418.2) shall not be used.
753,411
I
Protectivemeasure:Automaticdisconnectionofsupply
753.411.3.2 RCDs having the characteristics specifled in Regulation 415.l.l shall be used as disaonnecting devices. In the case ofheating units which are delivered flom the manufacturer without exposed-conductiye-parts, a suitable conductive covering, for example, a metal grid with a spacing ofnot more than 30 mm, shall be provided on site as an cxposed-conductive-pat above the floor heating elements or under the ceiling heating elements, and connected to the protective conductor ofthe electrical installatiofl.
rll
be
NOTE 1: Whcre Class II floor or ceiling heating units complying with the requilenrents of Regulations 412.1.1 afi,412.2.1.1 are uscd. the mesh metal grid detailed in Regxlation 753.411.3.2 is not required.
loru
NOTE 2: Lirnitation of the ratcd hcating power to unwanted tripping due to leakagc cu[ent.
753.412
7.5kW2l0Vor I3 kW400 V downstream of a30n
I
RCD may avoid I
Protective measure: Double or reinforced insulation
53.412.1.201 Where this protective measure is used as the sole protective measure for floor or ceiling heating units, complying with the requirements of Regulation 412.2. L I . the heating-ftee areas shall be readily identifiable. 7
!:.rtiott
The mesh metal grid detailed in Regulation 753.41 1.3.2 is not required.
The use ofthis protective measure as the sole protective measure for a wall heating system is not permitted. :.i._r1
to
:: rsed.
753,413
Protective measure: Electrical separation
Electrical separation shall not be used for wall heating systems (Section 413). r:.rsec1-
753.415 Additionalprotection:RCDS : :.l.]licc
53.415.1 Cilcuits srrpplying heating units shall llave additioral protection by the use of RCDs having the iharactedstics specified in Regulation 415.1 .l. Time delayed type RCDs shall not be used.
'-- ':
753.42
7
tltc
7
53.423
::
Protection against thermal effects Protection against burns
floor areas where contact rvith skin or footrvear is possible. the surface terrpelaturc r.i the floor shall be limited.
NOTE: FoI exarnplc. to no molc than 35 oC for flool Cl i\l IlCtirrideln.
I
hcating systcms. FoI additional it'.a::::::a:: a3i':rence can be made to I
753.424
Protectionagainstoverheating
753,424"101To meet the requirements ofChapter 42, special care shall be taken to prevent the heating elements creating high temperatures to adjacent material. This may be achieved by using heatirg units with ternperature self-limiting functions or by scparation with healresistant materials. The latter may be accomplished by placing on a metal sheet, in metal conduit or at a distance ofat least l0 mm in air froln the ignitable structure.
NOTE:
Dependent on adjacent material it may be prudeni to consider a larget separation distance.
753.424.201 For floor or ceiling heating systerns in buildings, one or more of the following measures
shal1 be
applied within the zone where heating units are installed to limit the temperature to a maximum of 80 'C:
(i) (ii) (iii)
appropriate design ofthe heating system appropriate installation ofthe heating system use
ofprotective devices.
Heating units shall be connected to the electrical installation via cold tails or suitable teminals. Heating units shall be inseparably connected to cold tai1s, fol example, by a crimped connection.
753-424,102 For wall heating systems, the heatiog units shall
be provided with a metal sheath or metal enclosure or flne mesh metallic g d. The metal sheath or nretal enclosure or fine mesh metallic grid shall be connected to the protecrir e conduclor of rhe supply circuir.
NOTE:
This requirement is irrtended to protect against the effects of overheating caused by a short-circuit between live conducto$ dre to penetratiol ofan en]bedded hcating unit.
753.5 Selection and erection of electrical equipment 753.51 Common rules 753.511
Compliance with standards
Flexible sheet heating eletnents shall courply \vith the requircments of BS EN 60335-2-96. Heating cables shall comply with IEC 60800.
753.514 ldentification 753,514.1 General The designer of the installation/heating systern or installer shall provide documentation for each heating system, containing the following details:
(i) (ii) (iii) (iv) (v) (vi) (r ii) (viii) (ix) (x) (ri) (xii) (xiii) (xiv) (xv)
Manufacturer and type of heating units Number ofheating udts installed Length/area ofheating units Rated power
Suface power density Layout ofthe heating units in the form ofa sketch, drawing or picture Position/depth of heatirrg trnits
Position ofjunction boxes Cables, eathed conductive shields and the like Raled voltage Rated resistance (cold) olhearing units Rated current ofovercurrent protective device Rated residual operating current of RCD The insulation resistance of the heating jnstallation and the test voltage used Product
infomatiot containing provisions about approved materials in contact with the heating units, with
necessary instructions lor installation.
This documentation shall be fixed to, or adjacent to, the distribution board ofthe heating system. Furlhermore, the requirerrerts of Figure 753 apply.
718.515
Preve.lti(xl
d irrnd dcltimental i[nuence
753.515.,tEle.ln.h.-ating.).IstrtjshallbeselectedanderectedSoastoavoidanyharnfuiinfluencebetweeD rhe hearine s) slem and anf elelm.al or non_electrical installations envisagedItmaterials other than lhose recommended are used in the sunoundirys ofthe heating units the manufacturcr shall Forexanple, an electric hearing system can aiTect other parts ofthe elecrricalinstallation such as reducing tlie cutenr car.ying capacity ofcables ofother circuils.he 10 high localambient lmperatuie cansedbvthe heating svstem'
NOTE:
753.515.101 Heating units shall noi 7
cross expansion.joints ofthe building or structure'
Wiring systems
53.52
753.520
lntroduotion
753.520.4 Heating-free areas For ihe neces$q, atachment of room ittings, heattug'free arcas shall be prolided in such emissioD is not lreventedby suclr Iittings.
753.522
I
wav that the heat
Selection and ereclion of wiring systems in relation to external influence
753.522.1 Ambient temperature (AA) 753.522.1.3Forco]d]eads(circuilwiring)andcontrolleadsnrstaliedjnthezoneofhealedsurfaces,thehcrease ofambient tempenhue shail be laken iDto account.
753.522.4 Presence of solid foreign bodies (AE) 753.522.4.3 Where hcahrg uritsrre insttlled aDd rhe
like lnay be caded out
without
there shallbe hcating-free areas whcre drilLing and
fixingbv screws
sk ofdamage to the units.
f'"\
fto ureerev E
I
337
Fig 753 A
description
of
-
lnformation for the user of the installation
thc 'heating system shall be providcd to the person ordering the work
Thc description shall contaiu at least the following information: a) Description ol tbe constnrction of the heating system, especially the installation depth of the hcati[g units;
b,
c) d)
I
o(rliol, diJIr:rrn witlt,nlormalion conceming Ihe distdbulion olthe healing circuits and their rated power; thc position olthe hcating units in each loom;
particularities which have been iaken into account when installing the heating units, for example, hcating-flee areas. complementary heating zones, heating free areas for fixing means penctruting inlo the coveriug materiall Data on the control cquipnrent used, with rclevant circujt diagmms and the dinensioned position ofUoor telnpcmture and weather conditions sensors. ifany: Data on the type of heating units and their
lraximun operadng temperature.
The installer shalI irrfonn the owner that the descdption ofthe hcaling system includes all necessary iuformalion. for .xanrple lbr r-epair work. Instructions for use shall be provided to the peEon orde ng the work upon completion. one copy ofthe instructions tbr use shall be pcmlanently fixed in or near each relevant distribution board The instructions fbr use shall include at least the lollowing data:
a)
Description ofthe heating systcm and its function;
b)
Opcmtion of the heating installation in the first heating period in the case ofa new building, for example, regarding drying outi opeHtio!1 of thc control cquipment for the heating syslem in the dwelling area and the complementary
c)
lT
d)
. c)
eating zone's.
ilanyr
Infornation on restlictiols on placing olfumiture or similar . additional floor colerings for exampLe. carpcts wilh a tllickness of>10 mm may lead to higi)cr floor tempeEtrires Nhich can adveNely affect the peformance ofthe heating system . pieces of lumiture solidly covering the floor and/or brilt-in cupboards shall only be placed on heating-{iee arcas lllitLrrc. sltch as calpets. seating and rest fllmiture with pelmets, which in pafi do not solidly cover the tlool. may not be placed in complcmentary healing zones. ifany;
In the
case
of ccilin.q hcating
roon height may
1) g)
systems. restricliolls rcgarding the height of fumiture Cupboards ofceiling where no heating elements are instalied;
of
be placed only below the area
Dimensioncd position ofcomplementary heating zones and p1aci11g areas; Statement that. in the case ofthermalfloo.. wall and ceiling heating systems, no fixingshallbe made into the tloor. wall ol cciling rcspcctively. Excluded from this requircment are heating-free areas. Altemativcs shallbe gi!en. where applicable-
APPENDICES Appendix
page
I
British standards to which reference is made in this standard
340
2
Statutory regulations and associated memoranda
359
3
Time/current characteristics of overcurrent proteciive devices and RCDs
362
4
Current-carrying capacity and voltage drop for cables
374
5
Classification of external influences
445
6
Model forms for certification and reporting
461
7
Harmonized cable core colours
484
I
Current-carrying capacity and voltage drop for busbar trunking and powertrack syslems
487
9
Definitions
-
489
10
Protection of conductors in parallel against overcurrent
497
11
Not Used
501
12
Not Used
501
'13
Methods for measuring the insulation resistance/impedance of floors and walls to Earth or to the protective conductor system
502
14
Determination of Prospective Fault Current
504
15
Ring and radial final circuil arrangements, Regulation 433.1
505
to
Devices for protection against overvoltage
507
17
Energy Efficiency
513
Appendix I
is nolmative, and is thlrs a requiremenr.
All other appendices
r+
multiple source, DC and other systems
are
intbnnative, and
are p(ovided as guidance.
APPENDICES pa9e
Appendix 1
British standards to which reference is made in this standard
340
2
Statutory regulations and associated memoranda
359
Time/current characteristics of overcurrent protective devices and RCDs
362
Current-carrying capacity and voltage drop for cables
374
Classification of external influences
445
r)
Model forms for certiflcation and reporting
461
7
Harmonized cable core colours
484
I
Current-carrying capacity and voltage drop for busbar trunking and powertrack systems
487
o
Definitions
4
-
multiple source, DC and other systems
489
10
Proteclion of conductors in parallel against overcurrent
497
11
/Vof Used
501
12
Not Used
501
'13
Methods for measuring the insulation resistance/impedance of floors and walls to Earth or to the protective conductor system
14
Determination of Prospective Fault Current
504
Ring and radial final circuit arrangements, Regulation 433.1
505
16
Devices for protection against overvoltage
507
17
Energy Efficiency
c tJ
NOTE: Appendix
1 is normative. and is thus a requirement.
All other appcndices are infomaiive.
and are provided as guidance.
333
APPENDIX 1 (Normative) BRITISH STANDARDS TO WhIICH REFERENGE IS MADE IN THIS STANDARD NOTE:
Certain British Standards have been withdrawn since the issue ofthe previor]s Edition. From the date ofwithdrawal. certif,cates and ma*s already au'alded may continue to apply to production until a date specified in the superseding standard. During the period between these dates. the withdmwn standard may be specilied in contracts. However. it should be noted that this appendix may not list such standards, as only current British Standatds are listed with some references to supcrseded standards. where standards are not dated they are a multiple standard-
References
Title
BS or EN Number BS 67:1987 1999)
Specification for ceiling roses
416.2.4 note 559.5.1
BS 88
The term "BS 88 series" . u hen u.ed rn these Regulations. rneans BS 88-1. -2 and -3.
132.4
(
433.1.204 53 3.1
Table 537.4 Appx 4 sec 4 Appl 8 sec 4
BS 88-l:2007
Low-voltage fuses - Pafi I : Ceneral requirements
BS 88-2:2013
Low-voltage fuses - Part 2: Supplementary requirements for fuses for use by autho zed persons (fuses mainly for jndustrial application) Examples ofstandardized systems offuses A to K. BS 88-2:2010 replaced BS 88-2.2:1988 and BS 88-6:1988 which have been withdrawn.
BS 88-2.2r19E8
Specification for fuses for use by authorized persons (mainly for industrial application). Additional requirements for fuses with fuse-lints for bolted connections Replaced by BS 88-2:2010 and withdrawn I/3/2010.
BS 1tE-3i2010
Low-voltage fuses - Part 3: Supplementary requirements for fuses for use by unskilled persons (fuses mainly for household and similar applications) Examples of standardized systems offuses A to F BS 88-3 :201 0 replaced BS ! l6l : 1971 which has been withdrawn.
Part 2 gC gG Table 41.2 Table 41.4 Table 41.6 433.1.20 r Appx 3 Figs 3A3(a)-(c)
Table 41.2 Tablc 41.4 ,133.1.201
533.1.2.2
Appx 3 Fi-s 3Al
BS 88-6:1988
Specification of sLLpplementary reqLrirements for fuses of compact dimensions lbr use in 2401415 V AC iDdustrial and commercial electrical installations Replaced by BS 88-2:2010 and withdrawn 1/3/2010.
BS 196:1961 Withdmwn
Speciflcation for plotected-type not,I-leversible plugs, socket-outlets cable-couplers and appliance-couplers with eafihing contacts for singlephase AC circuits up to 250 volts This standard has been withdrawn as the products have almost been replaced by those manufactured to BS EN 60309-1:1999 and BS EN 60309-2:1999.
BS 476
Fire tests on building matedals and structures
526.5
BS 476-4:1970
Non-conrhustible test tbr materials
554.4.1
8S,176-12:1991
Method oftest lor jgnitability ofproducts by direct flame impingement
BS 546:1950 (1988)
Speciflcation. Two-pole and earrhing-pin plugs, socket outlets and socket-outlet adaptors
Table
(iii)
5
5.
I
55i.1 .5 5 59.5.1(v) 105.512.2 70s.s53. r(iii)
BS 559:2009 BS 646:1958
+A2:2011
BS 951:2009
I
'1!0 ___ _
Specification fot the desigo and construction ofsjgns for publicity, decorative and general purposes Specification. Cartridge fuselirks (rated up to 5 amperes) forAC and DC scrvice BS 646 remains culacl1t but thc requiremelts for type B fuse-lin]G have been replaced by BS 2950:1958. Electrical eartling. Clarnps tbr earlhing and bonding. Specification
1
10.1
.3(i)
559.1 note 2 533.1.1
Table 55.1
553.1.5(i) 514. t 3.
r
BS or EN Number BS 1361:1971 (1986)
Title
References
Specification for cartridge fuses forAC circuits in domestic and similar premises Replaced by BS 88-3:2010 and withdmwn 30/3/20t0.
BS Ll62:1973 (1991)
Specification lbr purpose fuse links for domestic and similar -eeneral pulposes (primarily for use i11 plugs)
-ll.l
Table Table -11.4 533. r. r
Table 537.4 Table 55.1
r.5(i)
553.
BS 1363
l3 A plugs. socket-outlets. adaptors and connection units
433. r.10,1
Tablc 55.1 553. r.201 553.1.5
705.553.1(iio 722.55.101.0.201.1(i)
Appx BS i363-l:2016
-A1:201
15
Specif,cation for rewirable and non-rewirable l3 A fused piugs
Table 537.4
Specification for l3 A switched and unswitched socket-outlets
Table 537.4 559.5. l( v)
8
1363-2:2016
+Al:2018
705.5
t2.2
722.55.101.0.201.1(i) al
1363-3:2016 I :2018
Specifi cation 1br adaptors
-A
BS 1363-4:2016
Specification for l3A fused comection units switched and unswitched
+A1:2018
Table
5-17.,1
559.5.1(vii) Appx l5 Figs 15A
l5u BS 3036:1958 ( 1991)
Specificalion- Semi-enclosed electric fuses (ratings up and 240 volts to ealth)
to
100 amperes
Paft 2 Cr Table 41.2
thble,lt.4 432.4
zl3l.l.1nole I :113.
L202
,113.1.204 513.1
.1
53 3.1
.2.2
Appx 3 Fig 3A2(a) 3A2(b)
Afpx 4
sec 3
scc 4 sec 5.I sec
5.1.l(iii)
scc 6.1
BS 3535
BS 3676
BS 3858:1992 (2014)
Replaced by BS EN 61558-2-5:2010 Sality of rmDsfomers, reactors. power supply units and combinations thereof. Pafticular requiremeDts and tests for hansfonner for shavers, power supply units for shavers and shaver supply rLnits.
Appx 6 Cond. Repoft
iten 6.3
Switches for household and sirnilar fixed clectdcal installations. Speciflcation for general requirements. Replaced by BS EN 60669- I : 1999+A2:2008
Specification fot binding and identification sleeves for use on electric
514.3.2
cables and wires BS 4177:1992 (2015)
Specification for cooket control units
BS 44421:1989 (199s)
Cuide to electlical eafth monitoring and protective conductor pt.oving
Table 537.4 543.3.1
543.7.1.202(iiD 543.7.1.203(iv) BS 4573:1970+A5:20l6
Specification for 2-pin reversible plugs and shaver socket outtcts
553.
BS 4662:2006
Boxes for llush mounting of electrical accessorics. Requilcmcnts. lest
530.4.2
methods and dinensions
559.5.1(viii)
'A1:2009
r.5(ii)
I
I
34',t
BS or EN Number tss 412'7
Title
References
Clossan of e lectrotechnica I power, telecolmunication, electronics,
Paft 2 first para
lightrne and colour tenns BS 5266
Emergency liglrti:rg
r 10.
1.3(ii)
528.1 note 2 560.8.1 note 560.9 BS 5266-l:2016
Emergency lighting. Code ofpractice for the emeryency lighting premises
BS 5467:2016
Eicctric cables. Thermosetting insuiated, annoured cables of rated \ oltages of600i 1000 V and 1900/3300 V for fixed installations.
of
See
I
BS 5266
s22.6.204(i)
Appx 4 Table 4A3 Appx 7 Table 7C
BS 5.199
Gmphical symbols and sigru. Safety signs, including fire safety signs. Withdrawn and replaced by BS ISO 3864 l:2011
4721.55.3.7
BS 5655
Litis and service lifts
110.2(x)
BS 5655-l:1986
Safety rules for the construction and installation ofelectric lifts (Applicable only to the modemization ofexisting lift insrallatioN)
BS EN 8l-l:1998+A3:2009 available but still current. BS 5655 2r1988
Salety rulcs for the constmction and iNtallation ofhydraulic lifts (Applicable only to the modemization ofexisting li{i installations) BS EN 8l-2:1998+A3:2009 available but still curent.
BS 5655-l l:2005
Code ofpractice for the undeftaking ofmodifications to existing eiechic
lifrs (Applicable only to the modernization ofexisting lift installations.) BS 5655-12:2005
Code ofpracticc lor the undefiaking ofmodifications to existing
hydraulic lifts (Applicable only BS 5733:2010
10
thc modcmizarion ofexisting lift installations.)
Spccification for genelal requirements for electrical accessories
+A I r20 t4
411.3.3
s26.3(vi) 530.4.2 Table 537.4 559.5.I (vi)
559.5.4(v) BS 5803 5r1985
Ils
5339
Thcrrnal insulation fol.use in pitched roofspaces in dwellings Specification fbl installation ofman-rnade rnineml fibre themal insulation mats. Replaced by BS EN 13 t62.2012+At:2015 Firc dctection and fire alalm systems for buildings
Appx 4 Table 4A2 items 100
to
103
Table 4D5 r 10.1.3
528.1 note 2 560.8.1 note I
560.10 BS 5839-l:2013
Code
olpmcticc lor design. installation, colnmissioning and
rrsrntenancc of \y\rents BS 600,1:1012
BS 6007:2006 supe$eded.
ir
non-domestic premises
643.3.2 note I
Electric cables. PVC irsulated aild PVC sheathed cables for voltages up to and including 300/500 !', for elect c power and lighting
7
04.522.8.t1
A'72t.52t.2 Appx 4 Table 4A3 Appx 7 Table 78 Appx l5 Figs l5A & l5B note
Electric cablcs. Single core unsheathed heat resisting cables for voltages up to and including 450/750 V for intemal wiring see BS EN 50525.
withdrawr BS 6217 Withdrawrr
Guide to graphical symbols - see note at end ofthis table
BS 6220:1983 (1999)
Dcleted by BS 7671:2008, Corigendurn (July 2008)
BS 6231:2006
Deletcd by BS 7671:2018
BS 63,16:1997 (2005)
Electric cables. PVC insulated. a noured cables for voltages 600/ 1000 V and 1900/3300V
NOTE:
342
nris
has been
wirhdra*n but
is
Appx I note
of
Appx 4 Table 4A3 Appx 7 Table 7C
rctained within BS 7671 for historical purposes.
BS 6151
Deletcd by BS 7671:2018
BS 6500r200{)
Electlic cables. Flexible cords rated up to 300/500 Y for use with appliances and equiplnent intended for domestic. ofncc and similar er\ ironnlents. Withdrawn and replaced by BS EN 50525.
Appx 7 Table 7D
BS or EN Number
Title
References
::: t::
BS 6701:2016
Telecommunicalions equipn'ient and telecol11rruni,:;::::. Specification fbr installatiot'l, operation and rrrainleni ::ar
BS 6724:2016
Electlic cables- Thennosefting insulated. arnoured cablej ib. \ollases of i22.6.204(i) 600/1000 V and 1900/3300 Y for fixed installariors- ha\ ins to\ -{ppx zl Table 4A3 emission ofsmoke alld corrosive gases when affecled b\ fire. Appx 7 Table 7C
I10.1.3(vi) .144.1(iii) 528.2 note 2
Specification. BS 6891:2015
Speciflcation for the installation and maintenance oflo$.pressure eas installation pipework ofup to 35 1Ilm (Rl 1/4) on premises
BS 6907
Electrical installations for open-cast mines and quarries
I10.1.3(viii)
BS 6972:i988 (2012)
Specification for general requirements for luminaire supponing couplers fol dornestic, light industrial and commercial use
Table 537.4
BS 6991r1990 (2012)
Specification for 6/10 A, two-pole lveathel.-resistant couplers for household, commercial and light industrial equipment
553.2.l
BS 7001r1988
Specification for interchangeability and safety of a standardized lunlinaire supporting couplel
5s9.5.1(ii) ss9.5.4(iv)
BS 7211:2012
Electric cables. Thermosetting insulated and thennoplastic sheathed cables for voltages up to and including 450/750 V for electric power and lighting and having low elnissior ofsmoke and coffosive gases when affected by llre
Appx 4 Table 4A3 App 7 Table 78
528.i.4 note
559.5.1(ii) 559.5.4(iv)
A'72t.521.2
BS 7375:2010
Code ofpractice for building sites
BS 7410:201l+Al:2015
Code ofpractice for protective earthing ofelectrical installations
542.2.2 note 542.3.1 note
BS 7454:1991
Method for calculation ofthermally permissible short circuit curents, takjng into account non-adiabatic heating eflects
Table 43.1 note 2 543.1.3
+Al:2008 (2010)
dist bution of electricity on construction
and
704 note 704.411.3.1 note
BS 75,10
Elecflic cables. Guide to use ofcables with a rated voltage not
BS 7629-l:2015
Electric cables. Specification for 300/500 V fire resistant, screened, fixed installation cables having low emission ofsDoke and corrosive gasos &-hen affected bv fre. Multicore cahles
422.6(til
BS 7697:1993 (2010)
Nominal voltages for low voltage public electricity supply systems Withdrawn and replaced by BS EN 60038:2011.
Appx 2 sec
BS 7698-12:1998
Reciprocating intemal combustion engine driven altemating current gererating sets. Emergency powet supply to safety devices
560.6.13
BS 7769:2008
Electric cables. Calculation ofthe curent rating. (Some pafts ofthe BS 7769 series are now numbered BS IEC 60287 series. eventually all parts will be tenumbered.)
exceeding 450/750
V 560.8.I note I Appx 4 Table 4A3 15
523.3
Appx 4 sec I sec 2.1 sec 2.2
Table 483 note 2 Table 4C2 notes 1 & 2 Table 4C3 notes I & 2 Appx 10 sec I note, sec 2 para 7
BS 7769-1.1:1997
Has been superseded/withdmwn and replaced by BS IEC 60287- I- l:2006+A l:2014
BS 1769-1.2:1994 (2005)
Cunent rating equations (100% Ioad factor) and calculation oflosses. Sheath eddy cllrrent loss factors for two circuits in flat fonnation
BS 1769-2.2:1997 (2005)
Thennal resistance. A method for calculating reducdon factors for groups ofcables in free ait protected from solar radiation
BS 7169-2-2.111991 (2006)
Thermal resistance. Calculation of themal resistance. Section 2.1: Calculation of thennal resistance
BS 7769-3.I :1997 (2005)
Sections on operating conditions. Reference operating conditions and selection ofcable type
BS 7846:2015
Electric cables. Thermosetting insulated, armoured, fire-resista[t cables ofrated voltage 600/1000 V for flxed installations, having lorv emission olsmoke rnd corrosire ga5es when dmected by Iire. Specrhcarion
4)2.6(11) 522 .6.204(t)
560.8.1 note I Appx 4 Table.l-\l
BS or EN Number
Title
References Appx 4 Table 4A3
BS 7889:2012
Electric cables. Thermosetting iNulated, ullannoured cables with a \olrage of600 1000 V lbr fi\ed insrallarrons
BS 7909:2011
Code ofpmctice for temporary electrical systems for entefiainment and related purposes
110.J.3(ix) 706.1 7
t1.1
717.I note 740.1.1 note
I
BS 7919:2001 (2006)
Electdc cables. Flexible cables rated up to 450/750V for use with appliances and equipment interded for industdal alld similar environments Replaced by BS EN 50525.
BS 8434
Methods oftest for assessment ofthe fire integrity ofelectric cables
560.8.
BS 8436:2011
Electric cables. Speciflcation for 300/500 V screened electric cables having low emission ofsnoke and corrosivc gases rlhen affected by fire, for use in walls, pafiitions and building voids. Multicore cables
522.6.201ti) Appx 4 Table 4A3
BS 8450:2006
Code ofpractice for installation in ships
BS 8488:2009
Specification for prefabricated wiring systems intended for permanent connection in fixed installriions
52t.20
RS 8491:2008
Method for assessment offire integrity oflarge diameter power cables for use as components for smokc and heat control systems and certain other active fire safety systems
560.8.1(iii)
BS 8519:2010
Selection and installation offire-resistant power and control cable systerns for life safcty and fire-fighting applications. Code ofpractice
+Al:2010
BS 8573:2012
BS 9999:2017
ofelectical and electronic equipment
Electric cables. Thermosetting insulated, non-armoured cables with a l,oltage 0f600/1000V. for fixed installations, having low emission of smoke and corrosive gases when affected by fire Code ofpractice for lire safety in thc dcsign. rnanagcmcnt and use
of
r(iii)
I10.2(iv) )
110.1.3(x)
528.1 note 2 560.8.1 note l 560.1I
422.6tii) Appx 4 Table 4A3 I
I0 Ll(x)
buildings tsS
AU 1:l9a:1980
(1e87) BS
AU 177a:1980
(r987)
Specification for electrical connections between towing vehicles and trailers with 6 V or 12 V electrical equipment: type 12 N (nomal)
A72l.55.2.6(i) A72l .s5.2.6(iii)
Withdrawn
Table
Specification for electrical conneclions between towing vehicles and
tlailers with 6 V or 12 V electrical equipment: type 12 (supplementary) withdrawn
S
BS EN 8I
Safety rules for the constrLlction and installation ofli{1s
BS EN 8l-1:1998 +A3:2009
Electric iifts (also known as BS 5655-1:1986 Lifts and service lifts ... etc) which is still cunent but has been superseded.
BS EN 1648
Leisur-e accommodation vehicles
BS EN 1648-l:2012
12
V direct cunent extra low voltage electrical installations. CaravaN
A72l
A72t.55.2.6(D A72 r .55.2.6(iii) Table
A72l
110.2(x) 528.3.5
708.
I note I
721.t BS EN 1648-2:2012
BS EN 1838:2013
12 V direct current extra low voltage electrical installations. Motor calavalls
Lighting applications - Emergency lighting
708.I note
I
721.1
r10.1.3(ii) 560.9
BS EN I2954:2001
Cathodic protectior ofburied or immersed metallic shxctures. Geneml principles ald application for pipelines
I10.2(xiii)
BS EN 13636:2004
Catbodic protection ofburicd metallic tanks and related piping
110.2(xiii) 712.3)2.2 rore
BS EN 14505:2005
Cathodic protection of complex structures
110.2(xiii)
BS EN 15112:2006
Extemal cathodic protection ofwell casing RS 7361-l was withdrawn and has heen reolaced bv this.
712.312.2 note
BS EN 15869
Inland navisation vessels
BS
344
EN 15869-1:2010
Electrical shore connection, three phase cunent 400 V, up to 63 A, 50 Hz. General requirements
730.1
730.313.1.101 note
References
Title
BS or EN Number BS EN 15869-2:2010
Electdcal shore connection. three phase current JOo 50 Hz. Onshole unit..alety requirernents
\-
BS EN 15869 3:2010
Elect cal shore cornectioll, three phase curenl
\ . up io
-100
up io
6l '\.
730.t 730.313.1.101 note
6-1
730.I
A-
50 Hz. On-board unit, safety requiremerts
BS EN 50085
Cable tr1lnking and cable
dllctirg systems for electrical insullarions
412.2.4. r (ii)(b) 422.2.1(11)
422.3.4 521.6 52.1
.t.5
527.t.6
5i0.4.3 7l r.521(ii) 7 r5.52 r.1(0
l
't t7
.52.2(t) 1t1.528.3.4 7
2.1
.2.l
.528
740.521.1
740.52r.1(i0 BS EN 50085
General requircments.
422.4.204
Cable trunking systems and cable ductil'Ig systcms intended for mounting on walls and ceilings
522.6.204(iii) 705.522.16(iD
l:2005+A1;2013 BS EN 50085-2-l:2006
+Al:2011 BS EN 50085-2-3:2010
Particular requirements for slotted cable tmnking systems intended fol installation in cabinets. Section 3: Slotted il1 cabinets
BS EN 50085-2-,1:2009
Particular rcquirements for service poles and selvice posts
BS
EN 50086
BS EN 50107
Spccillcation for condnil systems ior cablc rranagenlent withdra\\:ll and rcplaced by BS EN 61386. Signs and luminous-discharge-trbe installations operating ftoln a no-load iated outpul vo)tage exceeding I kV but not exceeding 10
I 10. r .l
kV
559.
l(
(i)
ii)
559.1 note 2
EN 50107 I :2002
BS
l
General requirernents
BS EN 50107-2i2005
Requirements for eathJeakage and open-circuit protective devices
BS EN 50117 4-l:2008 +A I :2011
Coaxial cables
BS EN 50171:2001
Central power supply systems replaced by BS EN 60623:2001 and BS EN 60896-11:2003
BS EN 50I74
lnlbrmation technology Cablirg installatioll
- sectional specification for cables for BCT cabling iD accordance with EN 50173 Indoor drop cables lbr systems opemtiig at 5 MHz 3 000 MHz
Table 4444.1(v)
443.1.1
444.1(v)
444.4.lnote A444.4
A444.5 528.2 note 2
Installation spccification and quality assurancc
444.4.10(0
hstallation planning and practices inside buildings
,144.4.10(iD
BS EN 50174-3:2011
Ifformation teclmology. Cabling installation. Installation plaDning and J'raclicei our.idc buildings
A444.4
BS EN 50200:2015
Method of test for tesistance lo fue ofunprotected small cables 1br use
s6o.8.
BS EN 50174-1i2009
+A2:2014 BS EN 50174-2:2009
A444.4
+!\212014
in emergency BS
(iii)
ril.
Co$r11on test methods for cables uider fire conditions. Test for verlical flalne spread of vefiically-mounted bunched wires or
cables. Standard (all parts) withdrawn and replaccd by BS EN 60331
:,
I0l
EN 50266
c ircr
r
note
BS EN 5028I
Electrical apparatus for use in the prescnce ofcombustible dLlst
BS EN 50281-l-1:1999
l-lecnical appardru. f,IoLeclcd by enclo.ures. Cunslruclion dnd lcsling withdra\\,n and replaced by BS EN 60079-0+All:2013 ard BS EN 60079-31:2014.
I
110.1.3(iv)
BS EN 50281-l-2:i999
References
Title
Bs or EN Number
Electrical apparatus protected by enclosures. Selection. installation atrd l)lairltenance withdrawn and replaced by BS EN 60079-14:2014 and BS EN 60079-17r2014.
BS EN 50281-2-l:1999 BS EN 50288
T.st nethods. Methods ofdetermining minimun ignition temperatures Mult!elernent rnetallic cables used in analogue and digital
Table A444.1(iv)
conllllunicatio and control TelecornmunicatioDs bonding networks for buildings and other strLlctuies
BS EN 50310:2016
444.1(iv) 444.4.10(iii) A444.1 note A444.1.3
Method oftest for resistance to lire of latger unprotected power and ionrrol e.rbler lbr u.e in ctnerpel'c) ctrcuit.
BS EN 50162:.2001
Switchcs for household and sinilar fixed installations Collateral
BS EN 50428i2005 +A2:2009
Table 537.4
stantlard
Switchcs and related accesso es for use in home and building electonic sr stems THBES)
Requirements for nicro-generating plants to be connected in parallel with public 1ow-voltage distribution netwol*s
BS EN 50438:2013
551.1 note 551.7.4 551.7.5 note 551.'7.6
Eadhing ofpowet installations excceding
BS EN 50522:2010
1
kV AC
142.2 ,142.2 note 3
442.2.1note Electric cables - Low voltage energy cables of rated voltages up to and including 4501750 V
BS EN 50525
1
559.s.3.2(iii) A721.521.2
AppxT Table 7D
BS EN 50s25-l- I l. ) rr a-.r ) )l 151
Electric cables. Lou, voltage energy cables ofratccl voltages up to and including 4501750 V (U"lU).
422.3.201 note 2
2-82. i-ll. j,ll
(llexible cables)
704.522.8.11 705.422.8 notc Fig 708 note 2
02.s22.23til)
'7
7
t1.52.1
'7t7.52.2(i) '7
11
72
r
.52.2(tt) .55.2.6(i0
7,10.521.1 note 2 740.5 5. 1 .1
Appx ,l Table 4A3 BS EN 50525-2-31. 3-41
Electric cables. Low voltage energy cables ofrated voltages up to and including ,150/750 V (Uoru). Cables for general applications Single core non-sheathed cables with lhelmoplastic PVC insulation
717.41 1.3. i.2 note Appx 4 Table 4A3
BS EN 50565-1:20i4
Elcctric cables. Guide to use for cables with a rated voltage not exceeding 450./750 V (Ugru). Gcneral guidance
422.3.201 note 521.9.1 note
BS EN 50618:2014
Electric cables for photo!oltaic systems
BS EN 60034-30-
Rotatirg electrical machines. Efliciency classes ofline operated AC
lr20l4
ltoror. (ll- coJet
BS EN 60038i201
I
CENELEC staDdard voltases
'712.522.8.1
App I7 sec 17.12 App 17 sec 17.12 note I Table 443.2 55 7.3.5.3 557.3.5.4.2
't2t.313.1.) Environmental testing. Test methods. Tests. Test KA' Salt mist
Appx
BS EN 60073:2002
Basic and safety principles for man-machine interface, marking and idcitification. Coding principles for indicators and acluators
514.1.1
BS EN 60079
Electrical appamtus for explosive gas atnospheres
BS EN 60068-2I I :1999
5
AF2
1r0.1.3(iii) 753.1
App 5 BE3 BS EN 600790i2012+A I l:2013
Explosive atmospheres. Equipment. General requirements
I
1t0.1.3(iv)
References
Titte
BS or EN Number BS EN 60079-10l:2015 (split into l0-l and
Explosive atmospheres. Classification of areas. Explosive gas atmospheres
r0-2) BS EN 60079-1.1:2014
BS EN 60079-17:2014
Explosive atmospheres. Electrical installations design, selection and erectio
422.3
Expiosive atmospheres. Electrical installations inspection and
613.t
560. r
maintenance
BS EN 60092 507:2015
Electdcal imtallations in
ships
110.2(iv)
small vessels
709.1 note 2 BS F.N 601,16-2:2000
Semiconductor convertors. General req rements and line commutated convertors. Self-commutated semiconductor conveters including direct DC converters
414.2 note 2
BS EN 60204
Salety ofmachinery. Elect cal equipn)ent ofmachines
110.2(xi) 460 Scope 464.1 note 3 537.2.3 note 537.3.2.1 note
BS EN 6020.1-1:2006
711.55.4.1
+Al:2009
7 t'7
.t.(\)
740.t.t BS EN 60228r2005
Conductols of insulated cables
Appx 4 sec I
BS EN 60238:2004 +A2:201 I
Edison screw lampholders
416.2.4 note 559 5 1.206
BS EN 6025s 26:2013
Measuring relays and protection equiprnent. clectromagnetic
Appx
5
AM-24-2
cornpatibility reqLlirernents BS EN 60269 BS EN 60269-l:2(X)7 BS EN 60269-l:2007
Low-voltage fuses General requirements withdrawn l/3/2010 General requiremcnts
+Al:2009 BS HD 60269-2:2010,
BS 88 2:2010 BS HD 60269-2i2013
Low-voltage fuses. Supplementary requirements for fuses for use by authorized persons (fuses mainly for industrial application). Exan,ples standardized systems offuses A to J
of
Low-voltage fuses - Part 2: Supplernentary requirements for fuses for mainly for industrial application) Examples ofstandardized systems offuses A to K'(also numbered BS 88-2:2010). use by authorized persons (fuses
BS EN 60269-3:1995
Supplementary requirements for fuses for use by unskilled persons (fuses rnainly for household and similar applications) RepJaced by BS 88-l:2007 and BS EN 60269-1:2007 and withdrawn
)/3/2010.
:
: lD
602tt9--i.j0l0
Iow roltage,fitses Pat -?.' SrppJerneDtar:r re.vrneDeDt' lbt tu'ee fttr use by wtskr//edpetsotts (fi6es malh/t rtr fiouseholdanclslizl;/ar applicarions) Examples ofsrandardized systelns offuses A to F (also nLrmbered BS 88-3:201 0). Plugs. socket-outiets and couplers for irdustrial purposes
( Table 537 .4 551.4.4 note
7t7.55t.6
=-rl
Ge(\elat
(equ eme[ts
?05.553.I
108.55.1.i 109.553.1.8
72t.55.t.l 722.55.101.0.201.1 730.55.1.1
740.415.1(vi) 740.s5.7(ii)
t I
I
l
--=-.ti+
BS or EN Number BS EN 60309-2:1999 +A212012
References
Title DjrnensioDal interchangeability requirements for pin and contact-tube
543.7 .1 .201
accesso es
543.7.1.202(ii) Table 55.1 5
53.1 .5
553.2.1
559.5.1(v) 70,1.511.1
705.553.1 708.55.1.1 708.553.1.8 Fig 708 note 2
709.55i.1.8 Fig 709.3
7t1.55.t 721.55.2.6 722.55. 101.0.201.1(i0,
(iii) 730.55. L
I
740.5s.7(i) BS EN 60309-4:2007
Switched socket-outlets and connectors. with or without interlock
+Al:2012
708.55.1.1
722.55.101.0.201.1(iii) 730.55.1.1
BS EN 60320-1:2015
Appliance couplers for household and similar general purposes. General
553.2.
r
requirements
BS EN 60332-12:2004+A 1l :2016
Tests on electric and optical fibre cables under fire conditions. Test for vertical flame propagation for a single insulated rvire or cable. Procedure for I kW pre mixed flame
422.3.4 422.1.203 527.t.3
560.8.1(iXii) & (iii) 7l r.521(D 717
.52.)
7)t .52t.2 740.521.1
BS EN 60332-3:2009
Tests on electric and optical fibre cables u11der fire conditions. Test for vertical flame spread of veftically-mounted bunched wires or cables
422.2.1
422.3.4 422.5
521.t.3
7ll.52l Household and similar electrical appliances. Safety. General rcquirements
A721.311.4(iii)
BS EN 60335-229:2004 +1.2:20lO
Particular requirefients for battery chargers
A721.55.9
BS EN 60335-2-
Particular requireme[ts for pumps
702.55.i
Particular lequiremeDts for sauna heating appliances and infrared cabins
703.55
Particular requirements for elect cal heating appliances for breeding and rcaring animals
105.4).2.6
BS EN 60335-1:2012
+Al3 r2017
41:2003
+A2r2010 BS EN 60335-2-
53:201i BS EN 60335-2-
7l:2003 BS EN 60335-276:2005
Panicular requirement. for electric fence energizers
I
10.2(xii)
705.1 note
+42:2015 BS EN 60335-296:2002
Ll(vii)
Pafiicular requirements for flexible sheet heating elements for room heating
753.5 r I
craphical symbols for use on equipment. Now withdrawn.
412.2.1.1 note
I 10.
+42:2009 BS EN 60417
end
See
Note at
ofthis Table.
Table 55.3
BS EN 60439(61439)
Low-voltage switchgear and controlgear assemblies
710.511.1
BS EN 60439-l:1999
Type{ested and partially type-tested assemblies. Withdrawn and replaced by BS EN 61439- L BS EN 61439-2 may also be appJicable.
712,s
.
r
BS or EN Number
Title
References
BS EN 604,15:2010
Basic and safety principles for man-rnachine inrert-ace- marLing and ideDtiflcation. Identification of equipment terminals. condu.ior terminations and conductors
Appx 7 sec
BS EN 60,146:2007
Basic and safety principles for manrnachine interface. markins and identification. ldentification ofconductors by colours or numerals Withdrawn ard replaced by BS EN 60445:2010
Appx 7 sec I
BS EN 60447:200,1
Basic alld safet], principles for man-machine irterface. identifi cation. Actuating principles
r
BS EN 60529:1992
Specilication for degrees ofprotcction provided by erclosures (lP .ode)
markiig and
+,\2:2013
I
I,l.l.l
522.3.1 522.4.1
527.2.3(i) & (ii) 702.5
t2.2
708.553.1.8
,\72t.55.6
I
A721.55.10 722.5
t2.2.202
'722.512.2.203 BS EN 60570:2003
BS EN 60598
Electrical supply track systems for luminaires Replaces BS EN 60570:1997 and BS EN 60570-2- 1:1995 which have both been withdrawn.
527
Luminaires
559.5.r(iii)
.t.5
559.3.4
715.521.1(v) 559.5.1(iv) 559.5.3.2(i) & (ii) 102.55.2
BS EN 60598 l:2014
Luminaires. Gefleral requilen]ents and tests Replaced BS fN h05q8- I :2U08 but rcmains currell.
Table 55.3 and note
BS EN 60598-l:2008
Lurninaires. General requirements and tests
Table 55.3 and note
BS EN 60598 2
Luminaires ParticLrlar requircments. Ground recessed luminaires
559.10
l3:2006 +A2:2016 BS LN 60598-2 I
8r1994 +A I :2012
102.55.2.
Pafiicular requirements. Luminaires for swimming pools and si applications
BS EN 60598-2
llr
Lun'inaies.
1997
ilar
702.55.3
Particular requirements. ExtraJow voltage lighting systems for filament
7
|.559.4.2.
lamps
7
t5.422.t01 .t
(iii)
715.521.1(ir) BS LN (r059ll'2
Pa icular requiremellts. Luminaires with limited sudace
temperatures
422.3.2 note
,122.3.8(iii)
24:2013
Table 55.3 BS EN 6060
I
BS EN 60617
Medical electrical equipment. General requirements lbr basic sat'ety and essential perfbrmance
710.1 note 4
710.512.2.1note Fig 710.1
Graphical syrrrbols for diagrams. Now withdrawn. See Note at end of this table.
Appx
BS EN 60623:2001
Secondary cells and battelies contai ng alkaline or other non-acid clectrolytes. Ventcd nickel-cadmiu111 prismatic rechargeablc singlc cells
560.6.10 560.6.11
BS EN 60664-l:2007
Insulation coordination for eqrLipnrent withil low-voltage systems Principlcs, requirernents and tests
Table 44.2 note
Table 537.4 note 1 note
443.6.1 534.1
BS EN 60669
Switches fol household and sirnilar fixed electtical installations
BS EN 60669 l:1999
General requirements. This replaces BS 3676.
416.2.4 rote Table 537.4
BS EN 60669-2-l:2004 +A 12:2010
Particula requirements. Electronic switches
Table 537.4
BS EN 60669-2-2:2006
Particular requiements. Elecffomag[etic l-cmote-control s\\,itches (RCS)
536.4.2.3 536.4.3.2 Table 537.4 Table A53.1
BS EN 60669-2-l:2006
Panic!Ll![ requiremcnts. Time de]ay s\yilches (TDS
Table 537.4
+A2:2008
)
L
1
BS or EN Number
Title
References
BS EN 60669 2 4:2005
Partlcular requirements. Isolating switches
BS EN 60670
Boxcs and enclosures for electlical accessories for household and sirrilar' fi xed electrical iNtallations
559.5.1(viii)
Cencral requircments
,122.5 note 3
Pa icular requirements for connecting boxes and enclosures
521.8.3
BS EN 60670-l:2005
536.4.2.3 536.4.3.2 Table 537.4 Table A53.I 530.4.2
+Al:2013 BS EN 60670-22:2006
Appx
15
Figs l5A
15B BS EN 60684
Flexible insulating sleeving
BS EN 60702.
Mineral insulated cables and their tenrinations with
I
:2002+A1:201
crcc'erting 750
5
V
543.3.201 a
mted voltage not
Cahles
422.6(1)
433.1.204 s22.6.20411) Table 52.1 543.4.8 s60.8. r(i) 560.8.1 note I Appx 4 Table 4A3
BS EN 607022:2002+A I :2015
Mineral insulated cables and their tenninations with a rated voltage not exceeding 750 V
BS EN 6(]7]
Classifi cation of environmental conditions
I
i
560.8.1(i)
l:1995
Classifi cation of gloups of environmental parameters and their se\erities. Stationary use at we&ther protected locations
Appx
5
AN
...
BS EN 60721-j-4:l9r)5 (2005)
Classillcation of groups of environmental parameters and their sevelities. Stationary use at non-weather protected locations
Appx
5
AN
...
BS EN 60896 I l:2001
Stationary lead acid batteries. General requirements and methods oftest.
560.6.10 560.6.11
BS EN 60721 (100s)
Vcnted typcs. General requirements and methods oftest
BS EN 60898
Specifioatiol] for circuit-brcakcN for overcuraent prolectiol for hoLlschoid and sinlilar installations
Table 41.3 Table 4l.6 432.4
433.1.20t
433.t.204 533.
l.l
Table 537.4 Table A53.1
'722.533.t0t Appx 3 Fig 3A4 Fig 3A6 Appx 4 sec 4 Appx 8 sec 4 BS EN 60898-1:2003 +A 13:1012
CircLrif breakers lbr AC operation
434.5.2 s36.4.2.1 Table A53.I
Appx 4 sec 5.5.2 BS EN 60898-12006
Citcuit-breakers lor AC and DC operation BS EN 60898-2:2001 remained curent up nntil I June 2010.
434.5.2 533. 1.1
Table A53.1
A721.533.1.6 BS EN 60904-3:201 6
Photovoltaic devices. Measurernent principles for terrestrial photovoltaic (PV) solar devjces with reference spectral irradiance data
BS EN 60947
1
on -r ollarc
.s itchgcar
a.rd control
tear
Part 2 STC 533.1.1
&
BS or EN Number BS EN 60947 2:2006
Title
References
Cir'cuit-bleakers
411.4.4 note 2 432.4
+A2:2013
433.t.201 433.t.204 531.1.1
531.3.2(iv) 53t.3.4.2 533.1.1 533.1.3 536.4.1.4 note
3
536.4.2.t s36.4.3.1
Table
53'7 .4
A53.I '7tt.4t0.3.4
Table
721.4t5.t 722.531.2.101
722.533.101 740.4t0.3 740.411 note
Appx 4 sec 4
Appx 8 sec 4 BS 1:N 60947-3:2009
-A2r20l
5
Switches, disconnectors, switch-disconnectors and fuse-combination
units
536.4.2.3 536.4.2.3 note 536.4.3.2 Table 537.4
I
I
537.4.\ Table A53.1 BS EN 60947-4-
l:2010+Al:2012
Contactors and motor starters.
starteN Electromecha
cal contactor and motor
I
43s.2
s36.4.2.2 s36.4.3.1 Table 537.4
BS EN 60947 5,1:2004
+A1:2009 BS EN 609,17-6I
Control circuit devices and switching elefreots Electromechanical control circuit devices
Table 537.4
Multiple fllnction equipment Transfer switching equipment
536.4.3.2 Table 537.4 Table A53.1 7t0.53',1.t
r2005+Al:2014
BS EN 60947-6-2:2003
Multiple function equipment Cootrol and protective switching devices (or equipment) (CPS)
BS EN 60947-7
Speciflcation for low-voltage switchgear and controlgear
BS EN 60947-7-l:2009
Ancillary equipment. Temlinal blocks for copper conductors
BS EN 60947-7-2:2009
Ancillary cquipment. Protective conductor terminal blocks fbr copper
I
I
Table 537.4 Table A53.1
122.533.t01 526.2 note
I
I
ti I
conductors BS EN 60950-l:2006
lnfolmation teclurology equiprnent. Safety. General rcquirements
444.4.9
BS EN 60974-9:2010
Arc welding eqtLipment. Installation and use
106.1
BS EN 60998
Connecting devices for low-voltagc circuits for household and similar
526.2 note I 55e.5.4(D
+A2r2013
pu1poses
BS EN 60998-2-l:2004
Particular requirements for connecting devices as separate entities wiih screw-type clamping units
7
BS EN 60998-2-2:2004
Particular requirements for connecting devices as separate entities with screwless-rype clamping units
'7t5.52t.tO1
BS EN 61000
Electromagnetic compatibility (EMC) BS EN 61000 is a multiple part standard
515.2
BS EN 61000-2
Elechomagnetic compatibility (EMC). Environmellt
Appx
5
BS EN 61000-4
Electromagnetic compatibility (EMC). Testing and measurement
Appx
5
t5.52t .l07
Appx 4 sec 5.5.1
AM AM
techniques BS EN 61000-6
i
Electromagnetic compatibility (EMC). Generic standards.
Table A444.1(i)
& (ii)
BS EN 61008-l:2012 +A11:2015
Residual curent operated circuit-breakers without integral overcurrent protection for househokl and similar uscs (RCCBS) Geneml rules
4lI.4.204 Table 4l .5 534.4.7 note Table 537.4
I
1 10.4 t | .3 .2.1
11t .410.3.4
12t.4ts.t 722.53t.2.t01 740.410.3 740.41 I note Appx 3 Table BS EN 61009- l:2012
+A l2:2016
Electrical accessories. Residuai curent operated cjrcuit-breakers with integral overcurrent protection for household and similar uses (RCBOs)
Table 41.3
General rules Superceeds BS EN 61001:2004+Al4:2012
Table 41.5 Table 4l .6 432.4 433.1.201
but remains current
34
4lL.4.204
433.t.204 131.5.2 534.4.7 note 1 Table 537.4 710.411.3.2.1
7tr.4t0.3.4 72r.4r5.1 722.531.2.t01 722.533.101
740.4t0.3 740.411 note Appx 3 Table 3A
Fig 3A4 Fig 3A5 Fig 3A6 BS EN 6103:1-2:2005 I
A1 :2013
Measurernent olslnoke densily
olcrbles buning under delined
conditions 7
r.s2t(i)
Auxiliaries for Jalrrps. Capacitors for use in tubular ffuorescent and other discharge lamp circuits. Ceneral and safety requircments
BS EN 61095:2009
Specification for electromechanical contactors for household and similar
536.4.2.2
purposes
536.4.3.l Table 537.4 Table ,A53.1
BS EN 61140:2016
Protection against electric shock. Common aspects for installatioll and equipment
Part2ClassI... Class Class 410
IL.. III ...
412.2.4.1note BS EN 61184:2008
Bayonet lampholders
+A1:2011
559.5.1.205
BS EN 61215:2005
Crystalline silicon tenestrial photovoltaic (PV) modules. Design quali{ication and type
BS EN 61241-10:2004
Replaced by BS EN 60079-10-2:2015.
BS EN 61241-14:2004
Selection and installation Replaced by BS EN 60079-14:2014.
BS EN 61347
Lamp controlgear
BS EN 613,17-l:2015
General and safety requirernents. Replaced BS EN 601347I
BS EN 613,17-2-2:2012
416.2.4 note
r2008+A2:2013 but still curent.
Pafiicular requirements for DC orAC supplied electronic step-do$n convertoE for lllament lanps
712.511.1
Table 55.3
71t.55.6 7
t5.1t4
715.414 notc 2 740.55.5
1
BS or EN Number BS EN I
6[47-2-
l:2014
BS FN 6r 386
Title
References
Lamp controlgear. Particular requirements for DC or AC supplied elcctronic contolgcar for LED modules
7
Conduit systens fol cable management
412.2.4.1(iiXb)
t5.414
715.414 note 2
A444.1.4 52
t.6
527. t.5
521.t.6 1.521(ii)
7r
7r5.521.1(i) 717.52.2(t) 717.528.3.4 721 .52t.2 "7)t.528.2.t
740.521. r BS EN 6i386-1:2008
General requ irerneuts. Replaced by BS EN 6I 3 86-
I7
r2008 bllt refiains
422.3.4
4)2.1.204 BS EN 61386-21:2004
Particular requirernents. Rigid conduit systcms
+All:2010
522.6.204(ii) 705.522.l6 705.522.16(i) 717.52.2 721 .521.2 740.521. r(i)
BS EN 61386-22:2004
Particular requirenrents. Pliable corldujt systems
1t1 .52.2
Padiclrlar requirements. Flexibl(- conduit systems
1t1 .52.2
+A1l:2010 BS EN 61186-23:2004
+A11r2010
710.52t.1 740.521.1 note 2
BS EN 61386-24:2010
BS EN 61439
Pafiicular requirements. Conduit systems buried underground
522.8.10 note 708.521.7.2 note 2 710.521. l0l ..1.2 note 2 740.521.1 note l Appx ,l Table 483
Low-voltage switchgear and controlgear assemblies General rules (see
1t2.2.t.1
also BS EN 60439)
,122.5 note
l
5i0.4.2 5l6..1.5 5l6..1.20 r 536.4.202
516.4.20i 543.2.2(ii) 557.1
710.51l.l 1)2.5lL.1 BS EN 61,139-l
General lules (see also BS EN 60419)
BS EN 6lzl39-3:2012
Low-voltage switcl1gearand conlrolgear assemblies. Distributiolr boalds intended to be opcratcd by ordinary persons (DBO)
Paft 2 LV switchge...
42 r.
r.20r
5.16.4.20
Appx
r
l,+
BS EN61,139,1:2013
Pafiicular requirements tbr assemblies for constrxction sites (ACS)
70zl.5l L I
3S EN 61.+19-6i2012
Pa icular rcquirements for
.114.5.1
busbar trunking systems (busways)
521.4 527
.
L5
L6 Appx ,3 scc I Appx 8 sec l Appx l0 sec I note 521
.
BS EN 6]534
References
Title
BS or EN Number Poweftl?ck systelDs
422.2.1(i\) 422.3.4 434.5.3 521.4 52',7.t.5
527.1.6
Appx 8 scc I Appx 8 sec 2 Appx 10 scc 2 ote BS EN 6I5341r201
Ceneral requirements
ApDx 8 sec I sec 2
l+A I :2014
BS EN 6153,1-21:2006
Particular requirements for powetrack systems intended lbr wall and ceiling mourltil1g
BS EN 61515:2009 +A l:2013
lnstallatiorl couplers intcnded for perma[ent connection to fixed
Parr 2: Prcfab
imtallations
system 521.201 526.2 note
uiring
I
553.2.I
5s9.s.4(iii) BS EN 61537:2007
Cable 1lay systems aDd cable laddcr systenrs for cable ]LaDagenelt
422.2
.
1(tii)
122.3.4 521.6 527.1.5 527.1.6
'710.5)l.t
BS EN 6I557
Elecln(a1 saiity ir1 lo\\'\,oltagc disllibuliorl systcrns uP to 1000 VAC and 1500 V DC. EqLripnlcnt tbr tcsting. nreasuring or Dr()nitoring ol protective measurcs. General r-equirements
BS FN 61557 2:1007
Insulation resistancc
Appx l.l Sect 1(2)
uS LN 615-s7-6:2007
Eft'ectivcncss ol residuai cLtnent devices (RCD) in TT, TN and IT
643.7.1(a) 643.7. r(b) 643.8
systcms.
BS I-N 6l5il-ll:2015
lnsulation monitoriog deviccs for IT systems
538.1.1 557.3.4.3
7r0.411.6.3.1
IIS F.N 61557 9:2015
Equipmerlt for insulatio[ fault ]ocation in lT systerns
4t t.6.4 538.2 557.5.1.1 710.41I .6.3.3
BS EN 61557-12:2008
Electrical safety in low voltage distribution systems up to 1000 V AC and 1500 V DC Equipment foI tcstirg, measuing 01 monitoring of protective measurcs. Perfomance measu ng and mo toring deviccs
App
17
sec I7.9
(PMD) Safely ofpower transforrners. power supplies, reactors and similar
4l r.8.4.1(i)
products.
1 11 .41 I
Gc[eral requilements and tests
7t7.4t3
BS EN 61558-2-l:2007
Parlicular rcquireDents and tests lbr separating transtbmers and power supplies incorporating separating transfomers for genetal applications
444.4.9
BS EN 6155IJ-2-4:2009
Particular requirenents and tests for isolating transfomrers alld power supply units incorporating isolating transfomrers
414.4.9 722.413.1.2 730.313. L 102 740.55.9
BS EN 6l55li-2-5:2010
Pafiicular requiremcnts and tests for hansfotmer for shavets. powcr sr.rpply units lor shavers and shavel supply units
553.1.5(ii)
BS EN 61558-l:2005 +A1:2009
.6.2(ti)
Sec 701 101.512.2 701.s 12.1(ii)
Appx 6 Cond. Repofi itein 6.3
3e
BS or EN Number BS EN 61558 2 6:2009
Title
References
Particular requirements and test for safety isolatins t"nslbrmeE and porver supply units incorpomtirg safety isolarins r.anstbrmers
4r4.3(i)
I
141.4.9 Table 55.3
I I
A721.113.4(iii) 715.4t4 740.55.5
BS EN 61558 2-8;2010
Particular requirements and tests for transfonners and po\\ er supph units for bells aDd chimes
4r4.3(i)
BS EN 6I558 I5:2012
Pafticular requiremerlts and tests tbr isolatil1g transfomrers for the supply of medical locations
411.4.9
BS EN 61558-223:2010
Particular requirements and tests for' transfonners for construction sites.
.111.8.4.1(i)
BS EN 6I643
Low-voltage surge protective devices
5
BS EN 61641-l l:2012
Surge protective devices connected to Iow voltage power systems. Requirements a1ld iest methods
2
7r0.5r2.1.1
3,1.1
534.4.4.1
534.4.4.6note1&2 Appx 16 Table l6A note 1.2
BS EN 61643-21:2001 +A2:2013
Surge protective dcviccs connected to telecommunications and signalling networks. Perfonnance requiremerts and testing methods
BS EN 61851- 1:201
Electric vchicle condr]ctive charying systen. Geneml requirements Current but partially replaced with BS EN 62752:2016
I
I kV AC - Part l: Common mles
&3
Part 2 EV Mode I 722.511.101
BS EN 6I936I r2010+Al:201,1
Power instaliations exceeding
BS EN 61995-l:2008
Devices for thc connection ofluminaires for household and sinrilar purposcs. Ccneral requiremerts
Table 537.4
Electrical accesso es. Resid al cuncnt monitors for household and
532.l
similar uses (RCMS)
518.4.1
BS EN 62020:1999 BS EN 6204{l I :2008
Unintcnuptible power systelrs (UPS). General and
sa1'ety
for UPS
412.2.3
559.5.4(ii)
560.6.12(iv)
-Al:2013 BS EN 620210 3:2011
L,nintermptible fower systenrs (LIPS). N,lcthod ofspccifying the perfonrance and tcsl r-equilemenls
560.6.12(iv)
BS EN 62196l:1012+A12r201,1
Plugs. socket-outlets. \'ehicle connecturs aDd vehicle inlets. Conductive charging of electric vehicles. Dimeusional compatibility and interchangeability reqUiremeuts for AC pin and contact-tube accessoies
722.55.201.1 (i\.). (v).
(vi) 722.53 1.2. r 01 722.531.2.101 note 722.55. 101.0.201. I (i\).
(v) & (\'i)
JS EN 62208:201 I
Empty enclosures lbr low-voltage srvitchgear and controlgear assenblics. Gc[eral requirements
530.4.2
3S FN 62262:2002
Degrees ofprotection provided by enclosures for electlical equiprrent against extemal mechanical iolpacts (lK code)
108.512.2.1.3 709.512.2.1 .4l1ii) -t
35 EN 62305
Protection against Iightning
22.512.2.203
110.2(ix) 131.6.2 note
41t.3.t.2 421.1.1 note 2
444.5.2(iv) 528.1 note
I
534.1 541.3
Appx 16 Table l6A BS EN 62305-1:2011
General principles
542.2.3
Appx BS EN 62305-2:2012
Risk managemerlt
5
AQ3
443.1.I 534.4.,1.4.2(i)
BS EN 62305-3:2011
-
--l,
-.*
Physicaldamage to structures and life hazard
& (i0
I
BS EN 62305
,1:201
1
References
Title
BS or EN Number
Electrical and electrorlic systenls !rithin struclures
514.1
I
4
I
note 534.1.4 4) Appr lo Table 16,4. Fig IbA5 rrote 4 514
1 ()
BS EN 62353:201.1
MedicaI clectlica) ecluiplrer]t. Rccu[-cnl test and alter repair ofmedical electrical equipment Replaced BS EN 62353:2008 but still curent
710.6
BS EN 62368-l:2014
Audio/video. infonnation and conniltnicatioD technology equipttrelrt
4.14.4.9
Sai'ety requirements
BS EN 62395 l:2013 BS EN 62423:2012
Elcctrical resistarlce tr'ace hcating systclrs lbr i[dust al and connnercial applications. Gcneral tnd tcstirg r!'quilctnents '[ype f ard typc B tesidual cun-cDl operatcd circuir-l]reakers with and
411
without iotegral overcLrnerlt proieclion 1bt housellold and similar tlses
53r.3.4.1
.4.4 ]oote 2
531.3.4.2
5t 1.3.6 533.t.1 Table A53.1 710.411.3.2.1
1t2.4t1.3.2.1.2 722.531.2.101
BS EN ISO 11,146:2012
Road vehicles. Conneclors lbr the electtical coDnectioD ofto]ving and towed vclicles. I 3-pole connectors for vehiclc's rvith l2 V nom inal supply voltage not inlerded to cross watet fords
A72r.55.2.6(i) & (iii) Table A721
BS EN ISO 12696:2016
Cathodic protection oi stcel ur concretc
ll0.l(xiji)
BS FN ISO 1317.1:2011
Cathodic protectioo ofharboL[ ilrsiallati ls
110.2(xiii)
NOTE or graphical symbols IEC 60617 is thc central standrrcls database tbr electlotechnicirl syrnbols. They used io be coveleil b,v BS 6217, BS EN 60417 and BS El'\ 60617. ID 2002 IIIC l.runched all br1 lins datirbasc lormat iirr the s;-r1rboi liblirr'1, available on subscr iptio. llonr the IEC n ebsite. Follo},ing thi5 de.lsion, 1r1 2004 CENELEC dccidc'd Lo cease Publi.aiiur oi EN 60417 irr 'paPer'lbrrn, to $'ithdrrw the then existing standards irnd li)rmall)r to adopt the IEC database 1{ithoui any changes lbr usc in Europc. Consequently, thr- Blitish StandArd rersiotts have norr'iriso been lvithdrl\\'n.
BS IEC 60287
References
Title
Number
i
Elcctlic cables. Calculation oldr!' rutcrlt raling
523.
(Somc palls ol'rhe US 7769 reries c trow ntrrllbcred BS IEC 60187 scries. c\entually all pafls \\'ill be rcn nlllerecl. )
Appx 4 sec I
Lr
scs 2.1 scc 2.2
Table
4Bl
note 2
lable 4C2 note I & 2 Tablo 4C3 note I & 2 Appr l0 sec 1 note. scc 2 para 9
BS tEC 60287-l-
Cable rating equations (l00o% load factor) iud calculatior oflosses (gerleral)
Appx 4 sec 5.6
Electromagretic conlpatibilily (EM(.). lnstallalioD and l11itigatiolr guidoliles Earthing antl cabling
444.1(vi)
Dcvices lor thc conncction of lumillail es fbr: household trttd sintilar puryoses. Generalrequirements
table 537.4 s59.5.1(ix)
l:2006+Al:2014 BS IEC 6IO()O 5. 2.:1997
BS tEC 6r995-l
Identification ofcores ir cables and flexiblc colds -fablc 5I basical]y ilnplcrnents thc Iequircrncrts of HD 308. Please [ote,
Pretace Appx 7 Sec
HD 184.5.51rt
Now lvithdrarvr.
Appx 7 scc I
HD 38,1.7.711 SIi2003
Exhibitiors. shows and stands
Preface
HD 108:2001
356
I
I I I
\orrinalvoltagcs for lo\\ \ oltage public elecn icity
BS -rr9- Ie.rl
HD 472 SI
suppl\
r: , Jr s\slenr.
| 708
iIl
IAPPx 2 scc Notes
or1
HD 60164
Low-\,oltage electrical installations
HD 60364- L:2008
Funalarnental prillciples. assesslrellt ofgeneral characteristics.... definitions
Preface
HD 60164-4-41:2007
Protection for sal'et!- Prolection against eleclric shock
Prcface
HD 60364-4-42:201l
Protectior fbr safety - Protection against thennal effects
Preface
HD 60364-4-43:2010
Protection against overcunent
Prcface
HD 60364-4 442t201)
Plotection lor sallty. Protection of low voltage irlstallations agaillst tempomry oveNoltagcs due to earth faL ts in the high-voltage system and due to faults in the lo$' voltage system Protection against transiel1t overvo]tages ofahllospheric origin or due to
Preface
HD 60364-4-443:20I 6
15
thc plan ...
Appx 5 BC Appx 5 BE2 Appx 5 CA2 Appx 5 CB2
Prcface
swjtching HD 60364-5-51 r2009
HD bolb4-5-51:20
L
I
Preface
Selection and erection ofelectrical equipment Common rules
Appx 5 Appx 5 BE2 Preface Chap 52
I Selection and erection ofelectrical equipment wiring systenN
Appx 5 CB2 Appx 5 CB3 Appx 5 CB4 :rD 6036,1-5-534:2016
Devices for protectioll against transient
:D
Eafthing a[angeo]eots
(10164 5 5,1:201 I
ar1d
'oltages
Preface
I
Prcface
I
protectivc conductors
::D(r0i64-5-55I:20l0
Lo$, voltage gcnemting scts
:D
Selection ancl erection ofelectrical
ti(1164 5-559r1{)ll
ove
Prel'ace
Prefacc
equipment Lunrinaires and lighting
installations
I -l
::
lnitial Verification
6036.1-7
Locations containing
:1007-A I l:201
rf ',
I I
Pr-e
60i6,1-(r:2016
a
face
I
Prelace
bath or shower
I
I
t{16:l-7-701:2005
Rooms and cabins corltaining sauna heaters
Pret'ace
6036.1-7-70,1:2007
Construction and demolitiorl site installations
Preface
Agricultulal arld lrorticultural prcmises
Preface
Conducting locations with restricted nlovement
Preface
.ol6-1-7 708i1009
Caravan parks- can'lping pa1*s and similar locatjons
Preface
.rll6.+-7-709:2009
Madnas and similar locations
Preface
.Lrl6-l-7-710:2012
Medical locatiolls
Preface
Photovoltaic (PV) s),stenlS
Pref'ace
I
',i6-1-7-71,1:2012
ExterllaI lighting installatiors
Pret'ace
I
-
161-7-715r1012
Extra-1o\r" voltage
-r6l-7-72 l:2009
Elect cal installatiolls in caravans
r(.-.1-7-722:20l6
Supplies
-
l(lS
I
r
rt)-l(r.l-7 705:2007
I6r)16'1-7-706:2007
I
''r6-1
7-712:201f)
161-7-729:2009 I6-{'7-7:10:2006
Pr-efacc
lighting installations
Pref'ace
and motor calavans
Prefa.]c
fol electric vehicles
(Jpelatlns or,lrJrntenance gangwa)
lPret)ce
s
I
I
I
fernporar) elcctt'1.'al in.rcllation. lbrtnrctures. dlntlselnclll de\ ices I fairgrounds. alnusenlent parks and circuses
ar
lPrelace
I I
I
,---.-
FprHD 6036,1-4-444: 2010(2012)
Measures against electronlagnetic disturbances
IrprHD 60364'5-53i
Protection, isolatioll. switching, cortrol and ]nonito ng
2014
Fprl{D 60-364-5-557:
Auxlliary circuits
2012 FprHD 60164-7-702i
Srvirlming pools and other basins
20r0 FprHD 6036,1-7-717:
Mobile or trarlspo(able
u
ts
2010
rECr
60038-Ed 7.0
IEC 6033l
Tests for electric cables under fire conditiolls , Circuit ilrregrity. Tcst mcthod for lire with shock at a temperaturc ofat least 830'C fbr cables ofrated voltage up to and ircluding 0.6/1,0 kV.
IEC 60131-l:2009 IEC 60131-2:2009 IEC 60311-3:2009
and with an ovemll dianeter exceeding 20 mn and with a[ overal] diametcr not exceeditg 20 mm tested ir a netal enclosurc
IEC 60164-4-
Protection agaiDst voltage disturbanccs and elecftomagnetic disturbances
560.8.l(ii) s60.8.1(ii) 560.8.
r
(ii)
44:2007+At:2015 tEC 60164-5-
Selection alld erection
ofwirirg
systen]s
52::009(201I) IEC 605021i2004+A,l:2009
Powcl cabies with extruded insulatiol and their accessories for rated voltages from I kV (U,,, 1.2 kV) up to 30 kV (U- : 36 kV) - PaIt l: Cables for rared
:
voltages
IEC 60617:2012
of I kV (U," =
1,2
kV) and 3 kV
(U,,,
:
3,6
Tablc 52.1 Appx 4 sec l
kV)
Centml standards database ol graphical symbols fbt use in electrotechnical
5 I,1.9.
I
.l
lleating cables with a rated voltage of300/500 V for comtbrt healing and prevention of icc fomratioll IEC (rl1,1(l:2016
Protection against electric shock - (lomnron aspects 1br installalion and
414. t
IEC 61201:1992
[xlra-low vohagc (ELV). Lil11it values. Also known
414.2 note
as PD 6536.
3
4.721.533.l PD 6516:1992 PD CLC,]lR 50,180:201
i
PD IEC/TR 62350:2006
Extralow voltage (ELV). Lin'lit values. Also knorrn as IEC 6120l. 'fechnical Repolt - Detennination of cross- sectional area ofconductors and selection of protective dcvices Cuidarce lor the corrcct use ot residual
cu
ent operated protective devices
414.2 note
3
5.13.3 note
Appx 4 sec 2.5 531.1.3 note
,1
(RCDs) lb| household and sirnilar use
DD CLC/TS 6I643.
Low vollace sulge protective dcvices. Sulge protoctive devices connectcd to
534.I
l2:2009
lou
514.1
volrage porver distribution systems. Selection and applicatioD principLes
lote
2534.1
Dote 2
514.4.1.6 531.4.2 534.4.4.4.2 note I
&l
Fig 534.9 Fig 16,{5 notc CLCi
358
rS 6164i-22:2016
Low-voltage sr;rge proteclive devices. Surge protective devices coluected to telecoinlrlu cations arld siguallilg nctworks. Selectio ard applicarioD principles
I
APPENDIX 1 7 (lnformative) ENERGY EFFIGIENCY 17
.'l
Scope
This appendix provides recommendations for the design and erection ofelectrical installations, including installations having local production and storage of energy, for optimizing the overall etEcient use ofelectdcity.
NOTE:
On-site renewable energy sources and other local production sources do not ofthemselves increase the effrcie[cy of an electrical installation. However, they do reduce the overall public electrjcity network losses as the consumpdon of the installaiion from the public supply is reduced. This may be considered an indirect energy efficiency measure. For instailation ofsolar photovoltaic (PV) power supply systems, see Section 712 ofthis Standard.
withir the scope of this appendix apply for new eleclrical installations and modification existing installations. Much ofthis appendix will not apply to domestic and similar installations. The recommendations
lt is intended that this appendix will
be developed into PaIt 8
ofBS 7671 in
of
a luture amendment.
Availability of electrical energy and user decision
17.2
Energy efficiency management should be so designed that it does not reduqe electrical supply availability and/or services or operation below the level desired by the user The user ofthe electrical installation must be able to take the flnal decision over whether or not to operate a ser.,/ice at nominal value, or optimized value or not to operate it for a certain time.
NOTE:
Examples are uhen sonteone is ill, the user may decide to heat the rcom at a higher temperature, even during peak consumption; when a company receives an urgent delivery ordet the workshop may need to work at an unexpected hour.
Design requirements and recommendations
17 .3
The desigrer should take into account the follou,ing without losing the quality of ser-vice and the performance the elect cal installation:
(i) (ii) (iii) (i\) 17
of
Load encryy prolile (active and passivc)
Availability oflocal generation (solar, wind, generator, etc.) Reduction ol energy losses in thc clcctrical installation Thc tariff structure ofi-ered by the supplier olelectrical energy.
.4
Design requirements and recommendations
Determination of load profile The main load demands within the installation have to be determined. The loads, together with their durations of operation, and/or an estirnate of the annual load consumption of the main load demands (in kWh) should be identified.
Voltage drop Consideration should be given to limiting the voltage drop within an installation to a level below that required by Regulation 525.202, to reduce the energy losses in the wiring systems.
Cross-sectional areas of eonductors Increasing the cross-sectional area of conductors will reduce the energy losses but will increase initial installation costs. The decision as to whether to do this should be made by assessing both the savings within a time scale and the additional cost due to the increased size. Practical constraints. such as size of terminations. will also affect the
sizing ofconductors.
NOTE: In some applications
(particularly industrial), the most economical cross-sectional area of conductor may be seveml
sizes larger than that required for thennal reasons.
Power factor correction Consideration should be given to irrproving the ioad power factol to reduce themal losses in the wiring and tariff penalties.
Power factol correct;on can be rrade at the load level or centrall),. depending on the tvpe of application. The complexity ofthe issue leads to carelirl consideration ofeach individual applicarion.
17
Determination of zones
.5
The installation should be dir ided into zones for the purpose of energy efficiency analysis. A zone represents a floor area in square metres (r.nr) or a location where the electdcity is used.
NOTE:
Zones may corespond. fbr example, tol
-
an industrial \\,orkshop a
floor
it
building *'indows or
a space neaL
a space
far from windows
room in a duelling irighrvay road lighting a hotel kitchen. a
Determining the usages within the identified zones
17.6
The use of a particular circuit or zone should be clearly identified to enable accumte measurement and analysis its energy consumption.
NOTE:
of
Exanples ofdifferent usages are: hot water production
17
HVAC (cooling and heating) lighting rnotors appliances.
Energy efficiency and load management system
.7
Requirements from the user Requirements lrom the user are the first input to take into consideration. These requirements will be the key input to design the energy efficiency management system.
Requirements on the loads The designer and installer must take into account the user decisions on selection ofenergy eficient appliances. The user may give priority to the usage ofthe different loads as an input ofthe load optimization process (e.9. load shedding). 17
lnputs from loads, sensors and forecasts
.8
Requirements on accuracy and measuring range Provision must be made to allow the measurement and recording ofenergy consumption throughout the major pafis of the installation, to provide for the management of that consumption. Accumcy of measurement should at least comply with the following:
-
the meter at the origin ofthe loads must be accumte for billing purposes and can be used for the measurement
-
at a lower level it may be necessary to provide measurement with an accumcy allowing sub-billing within the same entity. For example, a company such as a hotel lray wish to charge the departrnent for catering separately lrom the depafiment in charge ofenteftainment
-
at the lowest level of the final circuit directly powering loads it can be enough to provide information for following trends without precise needs for cuirent to power conversion.
ofthe efficiency ofthe whole installation
Meas[ement is a key parameter to detennine the efficiency ofthe installation giving the user an awareness of his or her consumption. Consequently, device accuracy and measuring range must be adapted to the intended use,
as
close as possible to the loads.
Loads
17 .9
Loads should be classified legarding their use/s acceptance of load shedding. Some loads, such as infomation technology equip[.rent systems, computers and TV sets, are not suitable for load shedding. Others, such as heaters, reliigeratols and electric vehicles, can accept a load shedding for up to a certain length of time without any impact on their service. For each type of load, an acceptable duation ofshedding in normal conditions should be determined. NOTE
_
51!
1:
Examples ofacceptable durations ofshedding are 50 ms for a lamp and
l5 minutes for a refrigerator or heate.
NoTE
2:
Infomation on the ability ofloads to accept. ol nor. load shed.lins and rhe coresponding duration(s) is usetul.
Energy sensors Energy-sensing devices should be ol at least the same class as the energy perfbnnance and monitoring devices defined in Amex D of BS EN 61557- l2
Forecasts
.",
be used as inputs to the energy efliciency management system, such as weather and occuparcy
11..".""1.r::
Data logging Historical data, where available, can be an input lbr making energy demand fotecasts. To achieve a design capable of delivering a high level of energy efficiency, all available erergy consumption data should be taken il]to account.
lnputs from the supplies: energy availability and pricing, smart metering
17 .'10
The user should consider infornation conceming the energy avairabirity and pricing which rnay vary with time. where the supply is a local source. the user should consider the minimum and/or the maximum available power and define the price ofthe corresponding energy based on the total cost ofownership
including fixed and variable costs.
lnformation for the user: monitoring the electrical installation
17.11
The installation should be designed to enable the measurement of its total consumption in kwh for. every hour of infolrlation, shoukl be logged and stored for a minimum ofone
each day This data, and the related cost of e[ergy year and be accessible to the user.
NOTE:
MuJtiple years ofdata can bc usefLrl foI eflecrivc treid analysis.
In addition. by thc use ofsub-netcri[g fol examp]e, the installation should be clesigned to enable rhe recording and saving of data for the consumptior of individuar or grouped roads totaling 97 % ofthe total load.
An energy efliciency rnanagenlellt system comprises monitors for the whole electrical installation, including loads, local production
and storage. It can [ranuaily (easiest cases) or automatica]iy (most situations) monitor the electrical installation so as to allou optirrization oithe overall cormumption ofthe systern, taring inio account tr,e user requirements and the irrput parameters coming fiom the public electricity .uppiy ,et*o.tl local eiectricity production and storage, the loads. sensors, and forecasts etc.
17.'t2
Efficiency measures for equipment
Motors and controls An AC induction motor will consume mo[e energy than it actually needs when operated at less than full-load conditions. This excess consurnption of energy is dissipated by the motor in the form of heat. A better choice of motor and motor control will improve the global energy efficiency ofthe electric motor system. Motors with a rated output of0.75 kw 375 kw must ineet either the IE3 efficiency level or the IE2 level and be equipped with a variable speed drive. The energy efficiency classes are as lbllows: - IE2 (High eflciency)
-
[E3 (Premium etliciency) IE4 (Super premium etlciency).
NoTE 'l:
Commission Regulation (EC) No 640/2009, as amended, implementing Directi ve 2005132/EC of the Europcan
Parliamert a1ld ofthe cotncil with regard to ecodesign requireneots for elect c motols. Reference may also be made to BS EN 60034-30-l Rotating electlical machines: Efficiency classes of linc operated AC rnotors (IE code).
As about 95 % of the operating cost of a motot' cornes from its electrical energy consumption, adopting a higher energy elliciency class according to BS EN 6003,r-30-1, especialry for high-Juty applications, .url., ,'igrrin*r, energy.
consideratiol should be given to the use of motor starters, or other motor contuol devices such as variable speed drives, to achieYe higher energv eiliclencr. panicularlv for eflicient management ofenergy for intensive consumption applicarion. {e p. qou cootrol ot l,rn.. nJrllp.. air corlpres.ors.;.
Exarnples of aspects to be considered are:
NOTE
reducing electrical energy consumption
optimizing the rated power reducing the inrush curaent reducing roise and vibration, in this way avoiding mecharical damage and failurcs within the air conditioning or heating systent better contol and better accuracy in achieving required flow and pressure.
2: h industry, it is understood
that 60 0/o of consumed electricity is used to tum motors and 63 % of this energy is used for applications such as pumps and fans.
Lighting Lighting can represelrt a large amount ofelergy consumption in an electrical installation, depending upon the type of lamps and luminaires selected for each application. Liglrting control is one ofthe easiest ways to improve energy efficiency. Therefore, careful consideration should be given to lighting control. The type oflamp, ballast switchgear and controlgear should be taken irto consideration when applying lighting control. Building regulations have speciflc requiren.rents on the selection of luminaire types for locations, the minimum required energy performance of luminaires and energy consumption per square metre (mr) ofthe installatio[.
NOTE:
Solutions fol lighting control can irnprove the energy emciency by more than 50 o%. These systems should be flexible ald designed for the comfort of thc users. The solutions can range from very small and local, such as with timer and occupancy sensors, up to sophisticated customized and centralized solutions that are palt of complete building automatioll systems.
To operate lighting only when and where needed, permanent control oflighting may be implen.rented by using, for example:
-
movement detectors
dimming controls timed switches light-sensitiveswitches constanl brightness conlrol".
Heating, ventilation and air conditioning (HVAC) Considemtion should be given to:
-
the choice ofHVAC equiprnent depending on the installatior stlxcture and usage the approp ate control system to optimize environment control (e.g. temperature, humidity, etc.) depending on the usage and occupancy of individual spaces.
NOTE:
An example is a heatirlg system controllcd by
a
timer and thermoslat monito ng the temperature threshold according
to tbe expected occupa[cy. 17
.13
Distribution system
Wiring systems The cross-sectional areas ofconductors may be optimized to reduce losses. The electrical infrasrrucrure may be oprirnized b1 locating tlre power soulce at an appropriate position to minimize circuit lengths.
Tbe impact of thermal losses. offload consumption and on-load energy consumption of equipment connected in the wiling system, e.g. switchgear and controlgear, power monitors and relays included in an electrical circuit, is negligible compared to the energy used in the load and in the energy transportation.
Power factor correction Reduction of reactive current improves electrical energy efliciency by, for example, reducing thermal losses in
wi
ng systems.
Where a reduction ofreactive cuuent is l equired, the optimized level ofreactive curent should be determined. This Jevel generally depends on t)re public electricity supply contract.
s'6
ln order to reduce reactive curent, the following may be implemented:
-
selection of curent-usilg equipment with low reactive current component systerns for compensation of reactive energy by using capacitors.
NOTE:
Harmonic distortion rate ardvoltage inpulse are important considerations for selecting capacitor banks. The provisio[ ofharmoiic filters may need to be considered.
Energy It is of prime importance, in terms ofelectrical energy e{frciency, to ascertain by either calculation or measgrement, the energy consumption oleach item ofcurrent-using equipment.
Load profile Measurement ofthe energy used is necessary to give a load profile. This should be over a period of a minirnum 24 h to give a reasonable estimate of load pr.ofile.
NOTE:
of
The time period ofrneasurement is typically from every l0 mins to I hour The time period varies depending on the Lrsage. zone and the sector ofactivity, and also the season (especially for lighting and HVAC).
Voltage drop Voltage drop reduces energy efficiency ofthe electrical installation.
Where the voltage drop measuremert is required, voltage measurements should be made on the curent-using equipment ard at the origin ofthe circuit seNing the curent-using equipment.
517
STATU TO RY
-=
JT; :IT;J[:::':]I,='
MEMO
RAN DA
1. In the United Kingdom the following classes ofelectrical installations are required to comply with dre Statutory Regulations indicated below. The regulations listed represent the principal legal requirements. Infomation conceming these regulations may be obtained ftom the approp ate authority also indicated below.
Provisions relating to electdcal installations are also to be found in other legislation relating to parlicular activities. (i)
Distributors' installations
Electricity Safety, Quality and
gcncrally- subject to certain exemptions
RegulatioDs 2002 as amended
Continuity
Health and Safety Executive
Secretary of State for Scotland Secretar,v of State for Business, Energy and Industrial Strategy
(ii)
(iii)
(iv)
(v)
h-i)
Buildings generally subiect to certain exemPtiorls
\\rork a.tivitl Places ofwork. Non donestic installations
Cinematograph installations
Machinery Theatres and other places licensed for public
entertaioment, music, dancing, etc.
Electricity Safety, Quality and Continuity Regulations (Northern Ireiand) 2012
DepartmeDt of Enterprise, Trade and Investmeflt
The Building Regulations 2010
Ministry of Housing, Communities
(as amended) (1br
Englald and Wales)
and
local Government
The Building (Scotland) Regulations 2004 (as amended)
The Scottish Goveinment
Brlilding Regulations (Northern Ireland)
Department of Finance and
2012
Personnel
The Electricity at Work Regulations 1989 as amended
Health and Safety Executive
The Electricity at Work Regulatioos
Health and Safety Executive for
(Northern lrelal1d)
Northern Ireland
1991
Cinematograph (Safety) Regulations 1955, as arnend-.d mad-. under the Cinematograph Act, 1909, and/or Cinematograph Act, I952
The Secretary or State for the Home Government Oflice, and The
The Supply ofMachinery (Safety) Regulations 2008
Department for Business, Energy and
Conditions of licence under: (a) in England and Wales, The Local Covemment Ljcensing Act 2003
"cottish
Industrial Strategy
(a) Department for Culture, Media a1ld Spoft
(b) in Scotland, The Civic Government
(b) The Scottish Government
(Scotland) Act 1982
(\ii)
High voltage luminous tube
As (a) and (b) above
As (a) and (b) above
signs
:.
Failure to comply in a consumer's installation in the United Kingdom with the requirements of Chapter 13 of 3S 7671:2018. Requirements for Electrical Installations (the IET Wiring Regulations) places the distributor in the :.rsition of not being compelled to commence or, i1r cellain circumstances. to continue to give, a supply of energy :-r that iDstallatior. --
nder Regulation 26 ofthe Electricity Safety, Quality alrd Continuity Regulations (ESQCR)" any dispute which [ray .:ise between a consumer and the distributor having rel'erence to the consurer's installation shall be detemined by . rerson norninated by the Secretary of Statc (or the Scottish Govemuent in relatioo to disputes arising in Scotland) . the applicatiol'r ofthe consumer or collsumer's authorized age]rt or the distlibutor.
,:der Regulation 26 ofthe Electdcity Safety. Quality and Contirruity Regulatiors (Nofihem Ireland) 2012 (ESQCR \1r 2012)" any dispute which may arise benveen a consumel and the distributor having reference to the consumeL's :iailation shall be determined by a pcrson nolninatcd by the DepafiuleDt of Entelprise, Trade and Investment on :.= application ofthe consumer or consumer's authorized agent or the dist butor.
-5_
i
I
I
RegrLlatiorl28 olthe ESQCR 2002 (or ESQCR(Nl)2012) requires distributols ro provide thc
fbllowilg infonnatiol
to relevant persons free olcharge: 1'he maximun prospective short-circuit cuncnt at the supply tert'lrinals
rnaxirrul eafih loop impedancc olthe earh tault path ourside the irlstallation (Ze) The type and rating ofthe distributor's protective device or deyices lcarest to tbe supply tenlinals The
The type of eafthing systcut applicable to the colluectior The nrulrber ofphases ofthe supply
ofthe supply and the extent ol tlte pet.trritted variatior.rs The voltage olthe supply and the extent olthe pe nitted variatiors. TJre fi'equency
3. Where it is irtended to use protective multiplc eathing the distributor and the colrsurrer must comply with the ESQCR 2002 (or ESQCR(NI)2012). 4. Fol further guidance on the applicatiorl of the Electricity at Work Regulations (iuclucling the Nonhem Ireland version), referelce rnay be rnade to the following publication:
(i)
Electricity at Work Regulations 1989 Cuidance ou Regulatiorls (HSM5).
5. For installations in potentially explosive atmospheres tet'erence shoulcl be ntacle to: (i) the Electr-icity at Work Regulations 1989
(ii) (iii) (iv)
the Dangerous Substances and Explosive Atrrospheres RegulatiorN (DSEAR) 2002 the Petroleum (Consolidatior) Regulations 2014 tbe Equipment and Protcqtive Systems Iflterded lor Us!' in Potentially Explosive Atmospheres Regulatiorrs
2016
(v)
relevant British or Haunonized Standards.
Under the Petroleuln (Consolidation) Regulations 2012 Petroleulr Enfotcing Authorities are empowerecl to grzlr licences in respect of premises where petroleum spirit is srored and the autho ties Inay attach stich conditions a: they think fit, the requirelncnts may vary liom orrc local authority to arother. Guidance lnay be obtailed fiont the Energy Instilute (APEA/IP) publication Design, Constluction- Modificatiol, Maintenancc antl Decommissioning of Filling Stations.
6. For installations on caravan parks, the lequirements ol the licensing authority should be ascertained. Model Staldards were issued by the Depan[ent of the Elvilonn]ent in 1977 ulder the Caravan Sites ancl Coutrol of DevelopmeDt Act 1960 as guidance 1br local aLrthorities. 7. For ilstallations in thcatres and other placcs ol entertainme[t the requircmeuts ofthe licensing authority should be asceftained. Guidance o[ the recomr]reldiltions lbr places of entefiair]mert are available in ltchnical Standar.ds for Places ol Entertainrnent issued by 'l'hc Association of British Theatre Teclxicians. The Chartcreci llrstitute ol Enviromnental Health, The District Surveyors Association and The Institute o1'Licensing.
8. The Electrical Equipmcnt (Sat'ety) Regulations 2016. adnrinistered by the Depafiment lbr tsusiness, Energr and Indust al Stmtegy (BEIS), contain requirements lor saI'ety ot equiprnent designed or suitable for general use. Infomratior 01r the application ofthe Regulations is given il guidance issued by BEIS.
9 The Plugs and Sockets etc. (Sat-ety) Regulations 1994 rrade Lmder thc Consltnler Safety Act 1978- adrninisteretl by the Department fbr Business, Energy and Industrial Stmtegy, contains requirements for the saf'ety of plugs. sockets, adaptol's and luse links etc. designed lbr use at a voltage
ofnot
less than 200 volts.
10. The Health and Salety (Saf'ety Signs and Signals) llegulations 1996 r'equire ernployers to plovicle sat'ety srgrls. Guidance frorn the Health and Saf'ety Execulive L64. Sat'ety Sigls and Signals. specilies signs includiug emergerrcr esc!pe. first aid and fir'c saletl sien..
ll. Tl]e Mallagement of Health atd Safety at Work Regulations 1999 require ernployers and se'lt-ernployed persons to assess risks to workers and othe$ who rnay be allectc'd by their work ot br"rsiness. 'fhis is intelcled to euable thenl to identify rneasurcs they need to take to comply with the lar,v. Guidance liorn the Health and Safety Executr\ I INDGl63 gives advice on tltese regulations. For the pulposes of BS 7(r7l a risk appropriare clecn
icrlll
assessmerlr sbould involve an
sLillc.l pelson.
12. The Ptovision and Use olWork EqLripment Regulations i 99tl require curployers to cnsute that all wcuk equipneni is suitable for the puqtose tbr rvhich it is LLsed, is propelly maintaincd ancl that applopriate training is given. The Health and Strf'ety Execuli\ e has publishcd an Apprlved Code ol Plactice L22. Saie use ofu,ork ecluipmcnt, which
gives advice that has special legal statr.rs.
360
I3 ' Thc
E
Iectromagn.tic crrnlpatibilit\ Regu lations 201 6 pr ovide requirerre:--:.
lor electlomagnetic cornparibi lin.
:;: :. ei:rical an6 electronic
products
Other Reguiations televant to electrical installation include: The Personal Protective Equipnlert at Work Regulations 2002 (Eulopean Directive 89/656/EEC. HSE publication L25) The Wo*piace (Health, Safety and Welfare) Regulations 1992 (European Directive 89/654/EEC, HSE publication L24) The Manual Handling Operations Regulations 1992 (Europear Directive 90/269IEEC. HSE publication L23) The Wort at Height Regulations 2005 The Corstruction (Design and Management) Regulations 2015 (European Directive 92157lEEC, HSE publication L153).
I
I
15' In Novembcr 1988 the European electrical standards body CENELEC agreed on hamonizatiol of low voltage electricity supplies within Europe (CENELEC document HD 472 sl), implemented by BS 7697 Nominal vottages fol low voltage public electdcity supply systems. The measure is intended to harmonize nrains electricity s,pplies at 230 v wjthin EuIope. CENELEC has proposed three stages ofharmonization. Tu,o stages ofharnronization have taketr place, these being shown below. Effective date Pre-1995
I January
1995
Nominal voltage 240
v
230
V
Permitted tolerance
+6%t 6% +10%t 6yo
Distribution Code fofIicensed Distribution Operators ofCreat
B
I
Permitted voltage range 225 .6
-
254.4 V
2t6.2-253.0y
tain]
The Electricity Act 1989 (as amended by the Utilities Act 2000 and the Energy Act 2004) requires the DNos under rhe telms of their licences to produce and cornply with the Distribution Code. The Distribution Code has to be complied with by the DNO and by potential and existing Generato$. Suppliers ancl CLlstomers connected to or seeking connectiou to the DNO's distr-ibution systcm.
ll' Thc Construction Products Regulatiol1. adn]inistered by the Ministry of Housing. Cornmrurities and Local (;ovemn'lent, lays down requirements relating to obligatioirs of manufacturers in .elpect of tcstjllg. ..r,itying ':nd placing upon the malket, products intended for permanent installation in buildilg.s and conshultion ruorks. The electlical proclucts covered are 'Power. control and comnulication cables' in respect of their reacrjon to nre :erforntance The Regulation empowers Member States to deten ne levels olperfolnance reqr.rired for parlicular :nstallations ln the UK- MHCLG has lot exercised these powers in respect ofreaction to flre for cables. Guidance
:lay :
be given elsewhere, inclr"rdilg in Eutopean and
British Standards. For example, guidance
1br te1ecornmunication
rbling is in BS 6701 Telecomnunic.ttion.t e(lttipment an(l telecommlolicatiotls cdbliigSpetification li)r instctlldtion. ', t',ttiott ttttJ tnoitrtenttttt c.
i:r;
reactiolt to fire requir.ernents lol all cables are given in EN 50575 potter. <,onhvl Lud contn?unicctliotl . - (./r/, , /,,/ q,,trtl tffli, ,tri,ttt. ifi constructiotl ttor.ks subject to req(.tio]t lo.fire rcquiretltctlts. (AII other '. - lrtrerncIt: elcctrical. nreclrarrical. constructional, transmission rernain in existing ptoduct standards.) _eeneric
l.
d'""\
e**" ; fr=
361
APPENDIX 3 (tnformative) TIME/CURRENT CHARACTERISTICS OF OVERCURRENT PROTECTTVE DEVICES AND RCDs FUSES: This appendix gives the time/current characteristics ofthe following overcurent protective devices: Figure 3,A I Fuses to BS 88-3 - fuse system C Figures 3,A2(a)
& 3A2(b)
Serni-enclosed fuses to BS 3036
Figues 3A3(a)
88-2 Fuses to BS 88-2
& 3A3(b)
Fuses to BS
Figure 3A.3(c)
flise systems E (bolted) and G (cJip-in) luse system E (bolted)
CIRCUIT.BREAKERS: Figure 3,A4
Type B to BS EN 60898 and the overcurrent chamcter.istics ofRCBOs to BS EN 61009-l Type C to tsS EN 60898 and the overcurent characteristics of RCBOS to BS EN 6l 009- l Type D to BS EN 60898 and the overcunent chamcte stics ofRCBOs to BS EN 61009-l
Figure 3A5 Figure 34.6
In all ofthese cases time/cunert characteristics are based on the slowest opcratiflg timcs 1br compliance with the Regulatiols and have been used as the basis fot detenninilg the liuriting values of earth 1'ault loop impedalce prescribed in
C
hapter 41 .
Maximum earth fault loop impedance Regulatiol 4l L3.2 specilies maxiurum disco[reclion times for circuits. The nlaximrtm valtLes of eaflh fault loop irnpedancc to achieve the disconnectiolr time vary with the differelt rypes of protective devices and also betwecn manuf'acturers. Whelever possible clesignei.s should use the ntalrufacture/s
spccific data.
Altematively, thc impedance values give[ in 1ables 4l.3 and 41.6 can be used for BS EN 60898 circuitbreakers. These values arc far tnote onerous ancl in sonre cases may be difficult to achieve without illstalling larger sized cpcs. Regulations 41 1.4.4 to 411.4.204 state that the maximun eafth fault loop impedance tbr a pr.otective device is:
-
Uo
'
C'n.
I,
where: UO
is the nominal AC nns liDe voltage to Earth.
l.
is the current in arnperes (A) causirg operation
C,,,,,,
is thc minimLLln voliage f'aoto. ro take account ofvoltage variations depcnding oD tirne and plaoe" changing
lIilD\lblnrcr Iaps
NorE:
rIJ
ofthe protective device within the specilied titne.
of
orhr'r' ioD.iJcratrUns
For a low voltage supply givcn in accorclancc with the Electricity safcty. Regulations (ESQCR) as amerded, C,,,,, is given the value 0.95.
euality antl continuity
The tabulated values are applicable lbr supplies from distribution retwork opemtors. For other supplies the desiguer will need to determine the norninal voltage and calculate Z, accordingly.
I able 3A gives the tirne/cLrrreut perfbnnance criteria for RCDs to BS EN 61008-
I
and BS EN 61009-
l.
When impedance measurenents are nrade at ambient ternperature the procedure hereinafter described may be followed to take into accouut tl'te ificrease ol resistance of the conductors \\ ith the jncrease of temperature due to load current. For TN aud TT systel1]s in u,hich protection by automatic disconnection is provided by overcunent protective devices, such measurements are made to verify the maximu|n impedance value stated by the device manufacturer is not exceeded. hr the absence of manufacturerc' data, the values stated in Chapter 41 tables may be used.
The requirements of Regulation 411.4.4 or 411.5.4. as appropriate, are considered to bc met when the measured value ofearth fault loop impedance satisfies the following equatior:
z,(",)<0i9t'@ where:
Zdn,
is the measurecl impedance ofthe carlh fault cunent loop np to the most distant poini ofthe relcvant circuit from the origin ofthe installation (O)
U0 ["
is the
notrinal AC
is the
curent in amperes causing operation of the pl otective device within the time statcd in Table 41. I or within in Regulation 4l L3.2.3
nr, s
line voltage to Eanh (V)
5 s according to the conditions stated
C.r"
is the minirnum voJtage factor to take account ofvoltage variations depending on time and place, changing transfomler taps and other considerations.
NOTE:
of
For a low voltage supply given in accordance with the Electricity Safety, Quality and Continuity Regulations (ESQCR) as amended. C,",,, is given the value 0.95.
NOTE:
The above is one method ofconecting fbr thc effects of ten'rperatur-e difference: other methods are not precluded.
TABLE 3A RCD type
Rated residual
Residual
opemtillg current
current m-A
Ir,,
General
Non-delay
Dclay'S'
rnA
i
'l rip time Dts
Residual
cureut mA
l0
10
l0
i0
60
100
100
200
100
100
600
500
s00
r
100
100
200
100 500
'.-'
BS EN 61008-1 and BS EN 61009-1
- Time/current performance criteria for RCDS to
300 500
Trip time lns
130 min.
500 lnax.
t000
Trip time ms
150 150 max.
500
40 max.
1500
2500
000
600
lrA
50
20
100 nrax.
Residtal cLlrrent
500 60 mir. 200 max.
1500 2500
40 min. 150
max,
.f
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APPENDIX 4 (tnformative) CURRENT,CARRYING CAPACITY AND VOLTAGE DROP FOR CABLES CONTENTS Tables:
1A1 142 1A3 181 182 183 184 185 1C1 1C2 1C3 1C4 1C5 1C6
Schedulc of Installation Methods iu relation to conductors and cables Schedule ollnstallation Methods o1'cables (ilcluding Rel'ereuce Merhods) fbr deterrrrining cun-ent-carryrn! -calryrng capacity Schedule ofcable specificatiors and culent rating tablcs
Rating hctols (C'a) fol anbient ai| ternperatures other than 30
"u
Ratjng fhctors (Ca) 1br ambienl glound tenrpelatures othel than 20 'Cl Rating factors (Cs) for soil resistivity, tbr cables buried dilect or in underground conduit Rating 1'auors (Cd) 1br depihs of iaying otl'rer than 0.7 rn lbr dilect buric'd cables aud cables in bulied ducts Rating lirctors 1br cables haviug ruote thal4loaded cores Ratirtg lirctols (Clg)
lbl ole circuit or one multicore cable or
1br a group ofcircuits or multicore cables
Rating thctors (Cg) lbl nrole than onc cilquit, cables buried directJy in the grourd
Ratilg l'actors (Cg)
1br urole
tltan oue circuit. calrles in ducts buricd il1 thc grourrd
Ratirlg 1'actors (Cg) lbr groups ol nore than ouc nulticore cable oo trays or cable laddels Rating thcturs ((lg) 1br groups
ofole ot nrore circuits ofsiugle-core cables on trays
or cable ladders
Ratirg lactors (Cg) fbl cables elclosed iu infloor colrcrete toughs
a1
Sirtgle-core DoD arlrrouretl, with or rvilhoLrl shcath
4D2
Mr.rllicore rron-armourccl
1D3
Silgle-core aluoured (non nragrrclic arlrour)
1D4
M
1D5
I'-lat cabl!' wjth protecii!c co[ductol
4E1
Single-cole not-alrnoured, u'ith or without sheath
ttE2
Mullicore lou-annoured
lE3
Singlc-colc armorrred (non-mirgnctic anlour')
E4
Multicole aurour-cd
r"rll
icorr"'
ar
70 'Ci thennoplasLic insulatecl cables
niorn cd
90 'C themlosettirlg Copper conductors
60 oC thelnroscttiDg irsulated flexible cables 90 "C and 180 'Cl thelmosetting insulated flexible cables
Flexibie cables
Hexiblc cables Bale and exposed to tolrch, or having an ovelall thel.]uoplastic covering Bare ald neitlrer exposed to touch uor in contact with conbustible rnaterials
Mineral insulated cables
Single-corc lol-arruoured, uith oI willrout sheath
Multicore non-armolred
--3
Single-core arnroured (nolr-flagltetic an]our)
70 "C themoplastic insulated cables
Multicore annouled Siugle-core nol-annoLued, with or without sheath
-.2
MrLlticote non-anlouletl
Single-cole aunouled (r'ron-magllctic annour) M
u
90 'C thennoplastic insLrlatetl cables
lliuor',.' alnouretl i
I
__4=_
r
APPENDIX 4 (tnformative) CURRENT.CARRYING CAPACITY AND VOLTAGE DROP FOR
CABLES INTRODUCTION The recoutttrendations ol thrs appendix are iDtended to provide for a satisfactory life of conductors and insulation subjected to llie thelmal eUects oi carrying curent tbl plolonged periods of time in normal service. Other collsideratiolls ill'l'ccl thc cltoice of c|oss-sectional arca of conductors" such as the requirements for protection agaitrst electtic shock (( hrptcr 4l ). prolection against thcflral effects (Chapter 42), overcurrent protection (Chapter 43). roltage dlop (Seetion i25 ). aDd lioriting tenlpcr.atures fbr tenrinals ofequipment to which the conductors are curnected (Section 526). This appel-Idix applies to oon sl]eatlled arrd sheathed cables having a nolrinal voltage rating not exceeding I ,5 KV DC',
I kV AC or
The i'alues in-Iables 4DlA to ,lJ4A have been derired jn accordance uith the methods given in BS 7769 (BS IEC 602ti7) usi[s sttch dttttetrsions as specified in the i]rtemational standard tEC 60502-l and conductor resistances
given in BS EN 60228. Knorvl practical vatiations iu cable conshuction (e.g. form of conductor) and rlrarlutacturillg toicliitrces result in a splead of possible dilnensions and hcnce current-carying capacities for each cotldttctor sizc. Tabuiated currcut-canying capacities lrave been selected in such a way as to take account of tl']is spread of virlues ll ith salety and to lit- ou a srrooth cun e when plotted against conductor cross-sectional area.
Fot tliulticorc cables baring conductots with a cross-sectioual area of25 nrmr or largel either circular or shaped condLrctols are penllissible. Tabulated r,alues have becn dcr-ived from dimensions appropriate to shaped conductors.
All
the ctr[etrt-ciurying capacities giveu ale based on the ambient teflperature and conductor/sheath operating lcr'Ipcrature stated ir1 Tables 4D1A to 4F2A and 4CIA to 4J4A. 2
CIRCUIT PARAMETERS
2.1
Ambient Temperature
Thc cttrrent-carrying capacities iD tiris appendix aIc based upon the lbllou,ing reference ambient temperatures:
(i) (ii)
For lon-shcrLthetl aud shcathcd cables in air. iu.espective ofthe Installation Method:
Fol bulicd crblcs. either dilectly in thc soil or in ducts in the ground: 20
30.C
oC.
Whcte the atlbicul tetnpt'rature in the intendcd location of the non-sheathed or sheathecl cables differs from the c'f'crcncc atnbieut tenrpel'atLrrc. thc appropl iate rating thctors given in Tables 4B I and 4B2 are to be applied to the valttes of ctLretrt-carrying capacity set otn in Tables 4DlA to 4J4A. For buried cables. fuither corection is not Irceded if thc soil tctnpetatute exccr'ds the sclected ambient tempemture by an amouflt up to 5 oC for only a few t
u'ecks a year. Thc' mting f'actors r n
.lable
s 48 1 and 4ts2 do no1 take accoLrnt of the increase. if any, due to solar or other infrared Iadiatiou. Whelc rton shcittllcd or shealhed cables are subiect to such radiation. the cuuent-carrying capacity may be clerived by thc uredrods spcciliecl iu BS 7769 1BS IEC 60287).
2.2
Soil Thermal Resistivity
I'hc cutIeut-canling capacities tabulated in this appcndix tbr cables il the ground are based upon a soil thermal lcsistivit), o1 2.5 K urtW antl arc inteuded to be applied to cables laid in and around buildings. For other installatiolls. $helc in\estigalions cstablish lllorc acculate values of soil thermal lesistivity approp ate for the load to be catliecl. the \alues of cunent-carrying capacity may be derived by the methods of calculation given in BS 7769 (tsS
lE(
60287) ol obrained fionr rhe cable manLLfacturer.
In locations rvltere ti'ie cfiecli\,e soil tllemral resistivity is higher than 2.5 K.rnlW, an appropriate reduction tn culcllt-cartJing capacity shoLrld
be rnade or tlrc soil irmnediately around the cables should be replaced by a rnore suitable ,lraterial. Such cases can usually be recognized by vely dry ground conditions. Rating factors for soil thenal resistivities odrcr dran 2.5 K.nrw ale given in Table 4Bi.
374
2.3
Groups of cables containing more than one circuit
2.3.1
Methods of lnstallation A to D in Table 4A2
Cunent-caryiDg capacities giveu in Tables 4DlA to 4J4A appll'to:ingle circuits consisting of:
(i) (ii)
two rorl-sheathed cables or trvo single-core cables. oL one t\ o-core cable thlee lou-sheathed cables o[ tlxee singlc-cote cables, ot onc'three-cor" cable'
in the Where more tron-sheatlted cables. other than bare mineral insulated cables not exposed to touch, are installed applied' need to be 4C1 to'+Cl in Tables group f'actors specified rating same group, the NOTE: The group rating l'actors have bccn calcL ated o[ the basis ofprolongcd stead,v-stale operation at a 100 7o ]oad factor for all live conducror.s. Wherc the loading is less than 100 '% as t result of lhe .onditions of opetatior of the irstallation, the glotip rating t'actors may be higher'
Methods of lnstallation E and F in Table 4A2
2,3.2
The culrent-carryi|g capacities ofTables
4DlA to 4J4A apply to these Reference Methods
For installations on perforated trays, cleats al1d sifirilar, current-canying capacities for both single circuits and groups ate obtairred by multiplying the capacities give[ fbr the relevant arlangernents ofnon-sheathed or sheathed iables in fiee air, as indicatetl il1 Tables 4D lA to 4J4A, by the applicable group ratirg facto$ given in Tables 4C4 4G I A and 4c5. No group rating factors ale required {br barc mineral insulated cables not exposed to touch, Tables and 4G2A refer. NOTE 1: GroLp r.atilrg factors have been calcu]atcd as avclages lor thc Iange of conductor sizes. cable rypes and installation condition considered. Attention is drawn to the notcs Lmder each table. In sotne instances, a more precise cal(:ulation lray be requiled. NOTE 2: Croup rating factors have been calculatecl on the basis llrat the group collsists ofsimilal, equally loaded non sheathcd be or shcathed cables. Whcr.c a group contains various sizes of lor-she:therl or sheathcd cablcs. ca[tion shorrld exercised over thc curent loading of the smaller cables (see 2'3 3 below)' o11 the NOTE 3: A gr.oup ofsirnilar cables is takcn to be a gr-oup whelc the cument-catryrllg capacity ofall the cables is based not group spans the sizes iu conductolthe mnge of and whcre same maxinrurn pcnnissible conductor tcopcrature
nrore than thrcc adjaccnl sta[da1d sizes.
Groups of cables containing different sizes
2.3.3
.,ibulated group mtillg filctors are applicable to groups uonsisting ol suDilal equally loaded cables. Thc calculation : r.ating lactors firr groups containing dillereln sizes ol equally loaded sheathed or non-sheatbed cables is f'actols cantlot be tabulated but []tlsl be -:leudc]nt ol the total numbcl in the glonp ancl lhe nix o1'sizes. SLrch the scope olthis appelldix. Two is outsidc t)ictors ofsucll ol'calculatiol ,.iculateii 1br each gr.otLl'r. Tlrc trrethod .::cilic cxanrples ofrvhere suclt calculations nray b.'advisable arc gircn belorv' 2
Groups in conduit systems, cable trunking systems or cable ducting systems
.3.3.1
For a group contailing differeut sizes of non-sheathed oI sheathed cables in conduit systems, cable tnrnking lstemi or iable clucting systems, a simple fonnula for calculation ofthe group rating thctor is:
..=+ -{n rhere is thc group ratilg factor is the number ofcircuits in the group.
:
\\,ill reclucc the dangc'r of o\ elloldinc dle srllallel sizes but may ttortu1tler-LLrilization ofthe larger sizes. Such uniler-utilizatiolr can be aroided illarge tnd small sizes of
groLtp raring ihctor obtained by this cquation
.,:io
:..ihed or slteatlted cable arc not mixed in the
:
sc
sal11e
gloup.
oi a nlethod of calculation specifically intended tbr gror.tps cot]taiuina dli'rer:rtt iLr conduit will pt'oduce a tnore precisc gloup lalillg l'actor
sizes
ol uon-sheathed ot
-'.:hcd cablc
:
3,3.2
Groups of cables on trays
the a group contains dittlient sizes of non-shcathecl ot sheathed crrhl: l-,-.: :: lllil>I be exelcised olef glotLps 1br ilrtended : .::-rtrcalll of rriiu.::: { rnethod prcf'erable to Lise lt i: rnl lo;dilg ol the srraller sizcs. -:-:iuing ditll'rent sizes olnou-sheathcd or sheathcd cablcs.
:ri
_-r-_
The group rating t'actor obtaincd in accordance s itir the lbmula in 2.3.3.1 will provide a value which rnay be safely applicd. but which ruay Icsult u Lrnder- uiilr saii(rn
2.4
Conductors
Thc cunent-canying capacities and i, oitaga drop: rabulated in this appeldix are based on cables having solid conductols (Ciass l). or sflandcd corrdLrciors (Class 2). cxccpr tbf Tabl('s 4F lA to 4F38. To obtai[ the correct cullel1t-calrying capac ity or voltage drop tbl cable t1,pes s iir ilar to those coveled by Tables 4D l, 4D2,4E1 ar,d 4E2 but with flexible conductol-s (Class 5), the tabulatcd values atc ntuitipiied by the lbllo\\'ing l'actols: Cur reDt
Cable size
ralrying capacity
< i6 rrnll
Voltage drop
0.95
1. 10
0.97
1.06
Other calculations
2.5
In addition to calculatioos rclarcd to crLflclll-calryillg capacity, overload protection and voltagc drop described iD this appendix, otlter calcLllati(nrs ale also |equired 1oI the design of an electrical installatioll. These include calcLrlatigps of fault cuffent undcr variolrs conditions. Thc equations given in Technical Repon PD CLC/TR 50480 are leconulelded for calculating cilcuit inrpc'dalces, tiu]t cu[ents and other parameters. National Annex NA of PD ( LC/TR 50480 provides cietails of additional ancl altelnativc calculation methods that are intendsd fbr Lrse in the UK. The UK Natioual Annex includcs calculatiou Dtethods 1br the lbllowing:
(i) (ii)
1\ao non-shealhcd cables or
tlvo singJc cote cablcs. ot one two-core cable
three non-sheathed cables or threc singlc-core cilbles. or one tltree-core cable
(a) (b) (c) (d)
Cablcs in stcel cottdLrit
ln steel trunking Stcel wire annoutcd cablcs
Exterral cpc in parallcl uirh iutuout
1c) Aluminiul s ire rmourcd
3
single cotc cables.
RELATIONSHIP OF CURRENT-CARRYING CAPACITY TO OTHER CIRGUIT PARAMETERS
The relcvant symbols used
I,
the
il
tlre R.gulatiorls !uc as tbllows:
cu 'etrt-carrying capacity ofa cable tbl continuous service. under the particular installation conditions
coflcemed.
l,
tbe value ofcunent tabLriilted iI this appcndix tbl the type ofcable and installation metllod concerned, for il single circuit i11 thc arrbient Ierrpcrature stated in the curerGcanl,ing capacity tables.
I,.
the dcsigr cunent
ofthc circuit, i.e. thc culrcni illtended to be carried by the circuit in nomal service.
the lated culrcnt or cL lcnt seltirl-9 of lilc ptotectiVe device.
I.
ihe opclating cul'rcltt (i.c. the t'usiirg culr!'ut oI trippirrg curreut fol tl]e conventional operating lime) ofthe device plolecting the ci|crLit rgainst orctloatl. inslailation coDditions difler frorn those fol which values ofcunenLcanying capacity are tabulated in this appcnciix. The various ratilg tactors are identified as follows: a
mtillg f'actor to bc applred rvhcrc
thc'
Cr fo| ambie nt tcnlpeLatul-c Cc fbr circuits but ied itr the gtound Ca fol depth of bulial Cf tbr seuri-cuclosed tirsc tr-r BS 30-16 C,:
for glouPing
i tbr tlicnrrai insulation Cs tbl therrnal |esistivity of soil.
C
sctling ol thc plotcctirc dcl ice (ln) r]1ust not be less than the design cun'ent (lb) o: the circuit. at'ld thc ratcd clrrrL'ltt or cLtnent settiDg of thc protccti\e dcvice (In) Illust not exceed the lowest ofth. cLlnent-ca[ying capaciti.-' {1,.) ol any uflltc coDcluctors ofthe citcttit.
l'he rated cur'lcnt or
376
crLr'r'crlt
Where the overcLment device is irtended to a1'ford protection again nust not exceed lz (see paragraph 4 below).
l: n]ust lrot cxceed 1.45 lz and ln
Where the ovelcurrent device is irtended to al'ford fault current proteclion onl]. In can be greater thal] Iz and I] can -I'he protective dcvice musi be selected for compliance \\ lih Regulation 434.5.2. be greater than I .45 Iz.
OVERLOAD PROTECTION
4
Where overloaci protectiou is requirerl, tl'te type of plotection does noi ailtrl the cunelt-carrying capacity ol a cable tbr cortinuous service (Iz) but ir may all'ect thc choice olconductor sizc. The opclating conditions ofa cahle are ilfltLcncecl not ollly by the limititrg conductor ter]lperatule tbr contitiuous 5en ice. but also by the condoctor telrperature which lllight bc attailed during the corventional operating tit'De of the or erloarl protective device. in the event ofan overload-
This rneans that the operalilrg cul.lent ol the ploteclive delice Dust r]ot excced 1.45 Iz. Where dre protectiYc device is a lusc ro BS 8ll ser-ies. a circuit-bleakel ro BS EN 60E98 oI BS EN 60947-2 or a tesiclual current circuit-breaker with irltegral overclur.ent protection ro tls EN 6l 009'1 (RCIBO). this requir emeut is satisficd by selecting a value of L not less than llr.
h praetice. bccausc ol the standard steps in ratings of tises aud circuit-breakers, it is often necessary to select a valire of t,, exceecling lb. l[ thar case. beeause i1 is also uccessaly for lz itt tuttt to be not less tlla[ the selected value of ;r. thc choice of conductol closs-sectional alea n ay be die'tated by the ovelload conditions and the cuuent-cauying ca1)acity (tz) oi'thc cottductors will l]ot always be til]]y rlilised. lhe size leeded lbr a colducror protectecl against overload by a irs 3036 semi-ertclosed fise cal1 be obtained by the use of a rating lacror. 1.45/2.= 0.725. which resuits ir the sarue degree ol protcctiorr as that atlbrded by other gvcrloacl proteutive cleviccs. This tlclor is to be applied to the noninal rating ofthe filse as a divisor, thus indicating the rriniDrunr value of I requir cd ofrhc colductor to be protected. In this case also, the choice ofconcluctot size is dictated by the overloacl conditions and thc cun-ent-canyiug capacity (lz) oflhe conductols callrot be fully utilised. retlt-cal-ryillg capacilies tbr cablcs d ect rn ground ol in ducts i[ the grcund, given in this oC. Tire 1'actor- o I' L45 that is applied irr Regulation 43 3. I . 1 when appendix, are based au iulbient terupcrattLle of 20 colsidering ovr-rload piotcction assulles that the tabulated cuffcnt-caffying capaoities rue based on an ambient tenrpetature of 30 u(l. fo achieve the san re rlcglce of ovcllold pr-otcctiou where a cable is "in a duct in the ground" or "turicrl di1ect" as coutpaled rvith other installation methods a rating l'actor of 0.9 is applied as a multipliel to the
Thc tabulated
cul
tabulatecl curent-callyitrg capacity.
DETERMINATION OF THE SIZE OF CABLE TO BE USED Haviug establishc,cl the desigl curreut 1Ib) ol the cilcuit undel considcmtion, thc appropriate ptocedure descrihed in paragraphs 5.1 at1d 5.2 below wiil enable the desigrler to deter]uirle the size ofthe cable it will be Decessary to use.
it is uscluLl to idenrity the lengtlr ol'the cable lurr and thc pennissible voltage drop fol the supplied, as this nlay be an ovetricling cousideratiol'r lsee Secriott 525 and paraglaph 6 of this being "c1uipit.1t appeltlixl. Thc pcrlnissiblc volrage drop in mV divided by lu aLrd by thr' leDgth of run, will give the value of , oitage 4r.op jn nrVtA/m whicir can be toleratcd. A voltage drop rtot cxceeding that value is identified in the appr.opliatc tablc and the co espondirrg ctoss-sectional arca ol cortductot needed on this accoutrt can be read otT dilcctly beftrre auy othcr calculatiolls are lllade.
-A.s
,::.rt'
a preliprinary step
ofthe couditious oflomral load atd ovcrload is then determined rati[g lactors at]'ectirrg Iz (i.c. Ibr lactots fbr arnbient terrperature, gloLtpillg and thenllal insLrlation) ca[, if
The conductor size lcccssuly fitrm cotrsicierariou
\ll
desircd, be applied to the values 01'Ir as tnulripiie[s. This involves a process o1'trial and elror uDtil a cross-sectional area is r.eached so t|ar ; is not less rhan Ib and not lcss than In ofdny protective device it is illtended to select. ln any er cnt. if a r.ating lactor lor plotectio[ by a seuri-elqlosed Iirsc is rlecessary, this has to be appliecl to ln as a dilisor.
- '-n ing
lt
is therctbre'rrotc coll\,er)icllt to apply dll the iatirlg 1'actors to lu as divisors.
I his urethorl is used in itenrs 5.1 and 5.2 antl produces a value of cL[Te]rt and that value (or the next larger value) ;aD bc reailily located in the appropriatd tabLe of cLu-r'ent carrying capacity and the couesponditrg cross-sectional rr!'a of conductot can be identilied dilectly. lt shoultl be noted that the value of Ir appearing against the chosen ;ross-sectional alca rs not Iz. It is rot oecessaly to kLrow Iz where thc size ofcouductot is choscu by this method. Where overload protection is afforded by a device listed in Regulation 433'1'201 or a semi-enclosed fuse to BS 3036
5.1
For single circu its
5.1.1
.
--,: ,':
,
l',.1
.':
of dr'
cLLr.raltt ol l]le prot..1i\ c dc\ icc ( lu) b1 lnl applii.r:]i. r.:.:rl! iiL.IoIs t'OI anlbiert ((.r) . soll thclnt.rl lc:rili\rl\ ((')rnddepthof btrri.tl (- : :: r: T'lbLes 48 I to 484' tenlperiltlre
(i) Dir
iclc
thc [lted
For cables installed aboie gtottrrd C. and C1
(ii)
Ther tlrlhcr
dLr iclc [ry
: I'
ilny applical]le rating t'actor tbr thermal irsulatiou (Ci)'
or (iii) Therl tir hcr divicle' by the applicable rating factor for the type ofprotective device installation conditiol (C 1.. C.):
''
t
Equation
C. c. ('a C, Ct C.
(n) Whc[e the plotce ttr dcvice is a setDi-etrclosed fuse to BS 3036' ']
Cr': 0 725
Other-wise
Cr:
1
1
(b) Wheletirecatrleirlstallatiollrllethodis'ittaductintheglounrl'or'burieddirect''Cc:0'9Forcables installed abovc gt'ound C. : l.
Thesizeofcablclob.usedi5lobcsuchlilatitsta]]ulatedcun.ent.calryingcapacity(I)iSnotleSSthanthevalueof lated cufietlt ol thc proiccti\ e dc!icc adiusted as above'
5.'1.2 (i)
For grouPs
oftl]e pfotective device (In) by the applicabte In adclition ro rhe i'actols grven in 5. L I. clivide lhe rated curent rating lilctor lbr stoLrping (( q) givcn in Tables 4Cl to 4C6:
''' Ahemari\ely.
t1
c,
c.,
c, c,r ci cr c,.
Equation 2
that the cilcuits ofthe group are not liable may bc obtainecl lforl1 thc tbilowing lbtmulae. provided
to sirnultaneorts ovetload:
',
t.,C,CuC,Cr C.
'c"
Equation
3
Equation 4
ThesizcofcablctoberLscilistobcSuchlhlllitstabulatedsingle.circuitcurlent.carryingcapacity(lt)isnotless thanthevillueofllcalculateclttlaccordancewithcquatio],l2aboveol.wlreleequations3ald4areused,notless thar] thc larger 01'lhc tesultittg
t*o
values of lt
Where overload protection is not required
5.2
WlrcrcRegulation.i3.i3lappltcs.andtlrccableulldelconsideratiolliSnotlequiredtobeplotectedagainst by any applicable rating.factom, and the size ofthe or,erloacl. rhe clesign cun.cnt ol thc circuil (lb) is to be clividcd method colcemed is tr]"r lt' iut'ur"t"d tut'"nt-tu'-tf ing capacity ii; ior the installation cable 10 be uscd is to []c
"'tr' not less than the valuc of Ib adjLrslcd as above i'e';
,'' t L. f NOTE:
Wherc ovcrioad prole.iion is not r equired
5.3
C. -'
lo ,, L, cd c,
c. Equation 5
l'
Other frequencies
T)re current-carrying capacity ofcables canJlng' Currerlt latings statetl in the tables are lbt DC anci 50/60 Hz AC capacity at 50 Hz' may be no more than tbr c\ample. balancccl '100 Hz AL'coupaletl with thc ctll rcl]t-carry.ing
50%.Folsrrlallcablc's(c'g.".',',uyt,,.'.,',"atosupplyindividrralloads).thediffer.enceinthe50Hzandthe400Hz and voltage drop vary with fi'equency Suitable mtings cunent-cauying capacrties llray be negiigit'1" - C un:"'t toti'.tg should be obtaincd Jiorll
5.4
tilt nlanufaclurer'
Effective current-carrying capacity
cruent that can be carried in specifled The curt ent-cat rf itrg capacity of il cable conesponds to tlle lraximum tempemture for the type of steady-state lirrit of conditiolls withour the corldlrclors "-.""oirg ,ira permissible insulatiot't cotlccmed.
i' rcpf(\(llt llrc ell'citi\c 'ttrlettt-canying capaciq only rrhele no rating lactor the approp ate i't-n tnp"i'y tot"'ponds to the tabulated value multipliedby applicable Other$i'"' ttl" t ut' "nt-t""]'
I
Ire rrrlir<.
t,l Jt.lr.l,r
l.r'].'1.,1(u
groupirg antl tllerlllitL rn:- ''::r':- '": " tll T::-fl']-"f"O"Tl l'actor or t'actols lbr arubrerlt tcrnpcratute' may need to be Where hamontc cLIllallI: arc present lurther facto$ resistivity, for buried cables, as applicable applied. See section 5 5 ofthis appendix the ambient irssociatctl $ ith the conductors concemed, Irrespective of the type of ovelcurent ])rot"tl*: 9:'lt-: capacitv (as opposed to trrose used wher
T:,t:::tl::i*
'; ;:;; ;*l.t*Oq ffil]:|# :ffi,ii"s);Iffi ::+nrcarvirls are those given h Tables 4Bl and 4B2' ,.f.iti,rg ."frf" 5.5
four-core and five-core cables Rating factors for triple harmonic currents in
5.5,1
Rating factors
with four cores carrying current
without a conesponding reduction that. rT het'e the ttcutt'al conduitor can-ies cur-reDt be taken into account in ascertaining the cu1.re11tthe linc conductor"' the neutral conductor shall i" i".J ",t canying capacitY of the circuit
Reeulatiun 52J.6.1
:lrlc:
Thissecriorrisinterldedtocoverthesituationwheretherei5ctlllgnlflowin!,llrtlreneutralofabalancedrht.ee-plrase not uantel in the i1" line cut'tents llar irrg a halrnoiic eontent r'r hiclt does svstem. Suclt ll\'tllral ctlffents u" o* ,o
neutral.Therlostsigniticantftu'tooit*l'itf''doesnotcancelintheneutlalisusuallythetliirdharmonic'The line n'ay exceed the magnitude of the power frequency magnitude of the ue.,trul .o,t"'.'t tlt't tJ tt't-it'i'Jt]unrlo'it of cables ofthe capacity ,ig"in.a[t effect on the currellt-carrying culTent. h such a case the leutLal cur-ieit *iril1""." the circuit.
Thelatingl.actolsgiveninthisappenclixapplytobalancedthlee-phasecircuits;itisrecognizedthattl]esituationis lnrhissitrratton.tltenettltalconductorwillcarrythcharrnonic nroreoncrou5ito,l)tu1.,ol.rhethrccp}as.l'.r;f""a.O to o\'erloading ofthe neutral conductor-' currents iD additio]l to the unbal^rra"i
*.*ri.
S,"i] a situatiun car lcad
motor drives' cunetrts includes' lbr exatnple' variable-speed Equipnent likely to cause signiticaut hannonic t"tt ut tftose tbund in computers Further inlbnr.ration on hamrontc fluorescent liglrtilg b"nf, u,a uc po*e' ''uppi'"' 61000 disturbanccs can be fourd in BS EN
is within a four-core only apply to cables where the neutral conductor The rating t'actors given in the lbllowing table These rating factors onil .rorr-r".tionul aea as the line contluctors. or five_core cable and is of th. ,un,. n)'ut"riul to the fundamental ficquency of ,rrirJ rrurr*i" ."nErts measurcd with respect have been calculated on the basis
:-
"t theli1recurert.Wherethetotufl'u'''.t.'*itdistofiiolislroletl]an15%'duetothethirdharmonicorrlultiples phases of f"t1o"-a'" upptitaUt". Where there is an imbalance between rhereof, e.g. 9'r', 15'r', ctc. tfr., fo*.,
:.:ss
,r.ro."
,frriSO
V"
'"G ,tr"r krwer rating thctors may be applicable'
three loaded corductors' the current-carryirlg l-apacitv ol a cable with The tabulated rating t'actol's, when apptied to current in the fourth the where
rvill sive the current-canJug
":::::;,"iil;;';;;;i;".. conducto$ illto account.
::.illlSt : --; tile
*p"i", "f " cable with foui loaded conductors hanr.ronic current ir the line ,il;t,u a*,, rr,","r. rhe heatirs effect of the
be selected on the than the line cuffent then the cable size should Where the leutral current is expected to be higher hasis ofthe neutral current.
:-: e.l is
Wheretlrecablesizeselectiorrisbasedonaneutralcur.etttwltichisnotsigrificantlyhighelthanthelinecurlentit conductoLs. ;; reduce the tabulatect cutent-carying capacity lbr three loaded ;;;il
t
-'u
-i
lftheneutrtrlcLrnentismolethanl35%ofttrelirrecurlentaldthecablesizeisselectedonthebasisofthe the line .erl the, the three line ;";";;; *iri not be turly loaded. Ihe reduction in heat generated by neutml cu any apply to I"t't*l *'d''tcto' to the extent that it is rot necessaryoffour Ioaded condtLctors of'tsets the rl.u' g"""l.niij by* t; to take account ofthe effect rati g factor to the c*r.nu.u.rying-.ip;iiy ro, tt,r." rouo.a
:.::r
it'tg-
conductots.
: :;
than
"orducrors,
TABLE 4Aa
-: ilr0 l{z : . :lltil1gs
-
in four-core and five'core cables Rating factors for triple harmonic currents
'fhird harmonic content of line current*
:.:ecified
:,
:r pe of
:
--ctor
=
is
..::.:..rpriate
0
- il >33 45 >45
* NOTE:
Size selection is based
on line current
Size selection is based
on neutral current
1.0
15
>15
70
factor
0.
s6
0.lt6 I,O
disto(ion' Thc third hamronrc content expressed as total hanDonic
Example of the application of rating factor for third harmonic currents
5.5.2
Considel a three-phasc' circuil with a dc'sign ]oad (furdanrental culrent) ol58 A is to be installed using a four-core 90'( tltemosettirg insulatcd cablc. The cable n ill be instalied in a group with 3 other circuits on a pedbrated cable tray (nrclhod E or F) in an cxpccted rnaxiururn anrbicnt tempelature ol35 'C. The cable will be protectcd at its origin using a cilcuit-bleaker to BS EN 60898- i.
Case
1:
Load does not produce third harmonic currents
The desigll curent. [b. o1'rlrc tluee-phasc load is 5i3 A.
To satisfy Regulation 433.1.1. In: Ib. 5() lhc ralcd clr.rcDt ofthe circuit-brcakef, ln, is selected to be 63 A. The recluircd tabulilted cirrr!)1t-car'rying citpaciry. Ir. undcr the abovc operational conditions is to satisly: I,
i ,i
{$ here cir cuits ot thc glorrp arc assullrcd to bc liable to siurultaneous overload)
Flonr Table 48 l.
Ca
0.96 and fionr Tablc
) 't :---_6L:a< l\ 96 () 11 |
4( l. (lg .
0.77
^
From Tablc 4E4A, a l6 mrnr cable rvith copper conductors and steel wire allout has a tabulated current-carrying capacity of 99 A and hcncc it is suitable il thild lrarrnonic cuffents ale not prese]rt in the circuit.
Case
2:
Load produces an additional third harmonic content
-
THD-i = 20 %
For the sccond case it is assLmlcd thal tllc abovc' load is cxpcctcd to produce third hamonic distoltion of20 % in addition to the tindamental line current.
The titndanental line cuuel11 of the abovc ioad is 58 A. Sincc the third lrannonic content is betweer I5-33 %. the cable sizil1g is based upon the lire culrcDt. Bccausc thc load has 20 % third hannonic the design curent used for the sclection olthe protectivc device is givcn b1:
Ir,r =
58
,__:_______'__'_=
V
1'+ 0.2' = 59. I A
where: Ibtr : design curtert il]cluclil-q the cl]cct ot tiiird hanDollic cufients
4ll.t.l. Iu a Ib. so th. raled cLulcut o1'thc circuit-breaker, In, is selected to be 63 A. In addition. to comply u,ith the Regulation 13 1.2 j. ovL'rcLrflcr]t dctectiol must be provided for the neutral conductor. Thereibrc. a,l-pole protectire devlce uith o\!'lcuucnl llrotcclion of the neutral should be provided. The required tabulated cufient-carrying capacity- It, rurdcr thc abovc opcrational co[ditions is to satisfy: To satisty Regulation
I,, -lItat t (t i(, {ulljl'C(rr'\tlrl.ul ln(!lut,p.,r(:rs5trrl)(rltuDclraDietOSllnUltaneousO\erloaol fhc facto, of O.8O is takcn l'r'om thc abo\ c l blc
Applying the rbove grouliing arld tc.llipelature raling tirclors. the required tabulated current-carrying capacity is found
tobc99 IA. Fronr Table 4E4A. a l6 umr cable has a tabulatcLl cu[ent-carying capacity of 99 A, thus a rule-based syste]r may select a 25 mrn: cable whe'rcas a dcsigner nray excrc ise .iudg.)Dent afld select a l6 mllrr cable.
Case
3:
Load produces third harmonic content - THD-i = 42 %
Thc load is expected to producc tlrrrd hanlrolric clistoftjon of42 % of tirc fundamental line current. The frLndarrc'ntal line cul.] ent ol'thc above load is 58 A. Sirlce thc third hamlonic content is between 33-45 %, the cable sizing is bascd upon tlrc ncutl al cL[rc]rt \\' ith a lating firctol of0.86 applied to the current-carrying capacity ofthe cable. In addition. to conply with Rcgulation 4i i.2..i. olercunent cletection must be provided for the neutral conductor. Tbcrcforc. a 4-pole protcctir, c dcvicc ivith o\ c,!ru l cut protectjou of the neutral should be provided.
Th!'ncutral currcrt arising ionr thild hilruonics is givcn by
. lh, l,,r lu, f ouwhere:
I5,,
= neutLal curr'.'nt dLlc to thild hxrrllollic cLLlr-.llts
I,,
:
h
380
-
flnd.ur.nlxl line cLLrrcnt third hurnrr,nie rs il |cl-c.ntilsc ol'lhc tirlidanrcntal linc currcnt.
Ilence. the rleutlal cufer]t of tl're cilcuil is ltu T)reletb|e. the design cunent ofthe circurl
- .] r 0.42 r
dLLe
58
- -l \.
to third harnonics is
--l,\.
To satisfy Regulation ,133.1.1. li 2 lt. so the rated cu]Terlt of the circuit-breaker. In, is selected to be 80 A. The reqtiired tabrLlated cLrr ert-carrying capacity. lr- undel the abo\ e operational conclitions is to satisly:
I,:
CC11'\- (wbere circuits of the group
are assutued to be liable to sirnultancou: orcrload)
Applyi[g the above grouping and tenrpetatule ratiDg lactors. the requiled tabulated currert-cauying capacity
is
tbuucl to be 125.8 A.
I
F
rolrl I able 4E4A.
c
uu ent.
All
u
25 rnrnr cable is lecessary to con)pensate for the additional thenual eflect due to third hamronic
dre above cable seiectious are based on the current-canying capacity
ofthe cable: r,oltage dlop and other
aspects
of
design lrave not been considcred.
Harmonic currents in line conductors
5.6
Section 5.5 covers the etlect ol additivc hamrorlic cunents flowing in the neutral conductor'. The rating factors given in section 5.5 take account ofthe heati[g etlect ofthe third hanronic irr the ueutral as well as the heating effect ol the third harrnonic ir each ofthe Urc coutluctors. Wher e other haruorics arc prese[t, e.g. 5'r', 7'r' etc, thc hcating effect olthese harmonics in the line conductors has to be taherr into account. For smaller sizes, less tl'ran 50 n'ulr, the e1I'ect of hamrouiq cuuelrts can be taken into account
by applying the tbllowirrg tactor. Ct, to the lundamental design currert.
cr,: rvhercr I ,.50 llz cLrlletrr - n'i' harrr-rorric currert 11,,,
For'lalger conductu' sizcs the itcrease in cotduclol resistance. duc to skin aud proxinrity effccts, at highcr ilclllrcncies has to bc takel irto accorrrt. '1he resistance at halnronic liequencics can be calculated using thc r'quatiorls gi\cn in BS IEC 60287-1-1. TABLES OF VOLTAGE DROP ln the tables, values ol voltage drop are given 1br a currenl ot onr'anlpele lbr a metre ru)r, i.e. for a distance of 1 m along thc route taken by the cables. aud represent dre result ofthe voltage drops in all rlte circuit conductols. The r aiues o1'voltage drop assulne that the conductor-s are at their lnaxilnurn pennitled [ormal operating temperature.
Ihe values in tlre tables. 1br AC operation. apply to li-equencies
ir1 the
ralge 49 to 61 Hz and for single-cote
lrnoLucd cables the labulated values apply where the armour is bonded to earth at both ends. The values ofvoltage drop fbr cables operating at higher liequencies rnay bc substartially grl:ater. For.a given ruo. to calculate tlre voltage tlrop (in rnv) the tabulated value olvoltage drop pel aDrpere per meh€ for :he cable conccrned has to be urLrltiplied by the lergth of the run in rlrctles and by the cument the cable is intended cable cable.
:o caruy, nanrely, tire design current of the circuit (lu) in arnperes. For threelhase circuits the tabulated mV/A/m . alues relate to the line roltage and balauced conditions have bec-n assunred.
itrl
cables having conductors ol-16 urmr or less closs-sectional area, theil inductances can be ignored and erVrAlnr)r valucs only are tabulated. For cables having conducrors greatel than l6 rmDr cross-sectional al'ea the :rrpedance values are given as (D1V,'A/rr)2, together with the resistive componert (rnv/A/m)r and tbe reactive .!rnrporl!'l'rt (ruV/A/tn)x. . he dilect use ol the tabulated (mV,,Anrr)r or (rrv/'A/rn)z values, as appropriate, utay lead to pessimistically high -:lculated values ofvoltage drop 01, i1r other words. to r.rnuc'cessarily lor,v valncs of pemitted circuit lengths. For :raurple, where tlre design crLrrent ofa cilr:uit is signilicantly less thar the etlective current-canyilg capacity ofthe -roscn cabls. the actual voltage chop rvould be less thal1 tl]e cillculated value bccause d]e corlductof temperature
.:nd hencc their- resisrance)
will
be less than that on u hich the tabulated nrV
A nt had been
based.
I
A( circLrits. the use ofthe tabulated mV/A/Dt values (for the larger cable sizes, the tabulated (m!iAirrl)r \aluc\) lradi to a calculatcd value ofthc voltage drop higher than the actlal value. In some cascs it may bc advant.rgcoLrs fu tlrkc itccount ofthe load power factol when calculating voltage drop. As rcgards porvcr I'actol iD
Wherc a molc aceurat.
ai:.iirncnt of
the volragc drop is desirable the foliowing methods may be used.
Correction for operating temperature
6.1
For cables har ing condLrctors of cross-sectional area l6 mmr or less. the design value of mV/A/m is obtained by rlr.rltiplyrng thc tabr.rlatd r alue by a tactor Cr. given by:
c,= uhere
1p
is
230+t,,,(c^2cg'c"'co' $)1to :o) 230 + tp
the la\iD'lLllr pcrnitted llorrrrill
Equation 6
operatiug teurperaturc ("C).
This equation applics ortly where the o\cr.clrnent protective device is other than a BS 3036 fuse and where the actual al]rbient teurpcralufc is eqlral to or grcat!-[ thau J0 'C.
NOTE:
rbo\. equation is brseLl or the approxinrate Iesistance-temperature coefficient of0.004 pcr "C at tbr both.opl)cl' irnd alLrnriniLrm eonducto|s.
FoI conr cnicrlcc. th.
l0'C
For cablc's having conductols oi ctoss-sectional ?uea greater than 16 nurr. only the resistive component of the voltage drop is all'ecled b1, the tetupetatute and the t'actor Cr is therelbre applied only to the tabulated value of (DrviA/rn)r and the dcsign r alue of lnrVtAh.r)r is given by thc vector sum of Ci (mV/A/m)1 and (rnV/A/m)x.
l-ol vcry Iargc conductor sizc). rcactive part ( i
6.2
c
ii,hen
.ru
r
:
3
rr,here the resistive conrponent ofvoltage drop is much less than the corresponding ). this ralillg factor nced not be cousidercd.
Correction for load power factor
cab les hav ilg corldlrctols of closs-sectjoral area 16 mmr or less. tlre design value of mV/A/m is obtained approximatcly by nrLrltiplling the tabuiated value by the power factor ofthe load, cos O.
For
Fol cablcs having conductors of cross-sectionai alea greater than i6 mmr, the design value of mV/A/m is given approxinlately by: cos O (tabulatcd([rVrAlm.;.1 + 51n
g llsbulated(mV/A/m).)
For single-core cables in flat 1'ormation dre tabr.rlated values apply to the outer cables and may underestimate for the !oltage drop bet\\'ecu an oulcr cablc and thc ccntrc cable for cross-sectional areas above 240 mm2, and power tilctors greater than 0.8.
Correction for both operating temperature and load power factor
6.3
Fot patagraphs 6.I and 6.2 abore. where it is consideled approp ate to con'ect the tabulated mV/A/m values for bodl operatirg tempetature ard load pou er t'actor. the desigrl figure for urV/A/m is given by:
(i)
tbl cables having conductols of ctoss-sectional area
16
rlnt: or
less
Cr cos O (tabulatcd l'nV/A/m)
1ii)
tbr cablcs ha!i[g conducto]'s ofcross-scctional area greater thao l6 mml Cr cos O (tabulated
_
39L
(nrv/Aim)r) + sin O (tabulated (mv/A/rn)x).
Voltage drop in consumers' installations
6.4
The voltage dlop between the origin ofan installation and any load poinr should nor be greater than the values in the table below expressed with respect to the value ofthe nominal voltaee olthe installation. The calculated voltage drop should include any eff'ects due to hannonic currents.
TABLE 4Ab
-
Voltage drop Other uses
(i) Low voltage installations supplied directl_v- flom a public low distribLLtion systelr]
(ii) Low voltage instalJation supplied liom private LV supply (*)
(+) l he voltagc drop within each f,[al circuit should not exceed the valucs given in (i). Whcre the wiring systems ofthc installation are longer than 100 In. the voltage drops ildicated above may be increascd by 0.005 9/o per nietre ol'the wiling systeu beyond I00 m, $,ithout this i[c]ease being greater than 0.5 o%.
I
he vohage drop is detemlined ftoln the denrand ofdre cunent-using equipment. applying divcrsity factors whele applicable, or from thc vahLe ollhe design cunent ofthc cilcuit.
NOTE 1: A grcater voltage dnrp may bc acceptable fol a motor circuit during starting and lbr other equipment with a high imush curent. plovided that iD both cases the voltage variations remaiD within the limits specified in the relevant equiprnent stardard.
NOTE 2;
-l
he
following temporary co[ditiols arc cxcluded:
, -
voltage transicnts
voltage variatiorls due to abnonnal operatioll.
METHODS OF INSTALLATION
of irstallalion lol ulrich this appendix pl'ovides guidar'rce for the selection of the rpptopriatc cablc sizc. lable :tA3 lists the appropriate tables for selection of cui-rcnt ratings firl specific cable -fhe lo1'lstluctiol)s. Reference Melhods arc those rretllods ol illstallatiol lbl which the curreDt-cauJillg capacities cn in Tablcs 4D I A to 4J4,\ ita\,e becll deternirled (see 7. I bclow ). -:ir Table 4A2 lists 1hc methods
The usc ol'other rnclhods is lrot plecludcd ancl :e basecl on expclilrcntal rvorli.
ir
that casc'thc cvalLration of cu[cnt-carrying capacity may [eed to
Reference Methods
7.1
The Ref'elence Methods arc those methods of installation for which the cun'ent-canying capacity has bcen detennined -a\ test 01 c?rlculation.
NOTE
'l:
It is ilnpractical
calculate and publish cuneilt ratings tbr cvcry installation rnethod, sirce many would result in the a suitable (liIl']ited) oun1ber ofcurrent mtings have been calculated which cover all of the installalion nrethods stated m Table 4A2 a1ld ha!e beei called Relereuce Metbods. sanle clrnent
10
mti[g. Thclelore
Reference Method A, lbt exarrple, lnstallation Methods :ulticore cables iu conduit in a thermally insulated wall).
I
and
2 of Table 4A2
(nou-sheathed cables and
fhe wall consists of a[ outer weatherproof skin, tl]emral insulation and an inner skin of wood or wood-like :atelial having a thermal conductalce of at least t0 Wlm]K. The conduit is fixed such that it is close to, but not ::cessalily touchiDg. tlle inner skin. Heat fi'om the cables is assumcd to
escape througi] the innel skin only. The
:-.nduit can be metal or plastic. Reference Method B, tbr exantple, Irrstallation Method 4 of Table 4,A2 (non-sheathed cables ir conduit n'rounted : a \\'ooden or nrasonry wal]) and lnstallation Method 5 ofTable 4A2 (mLLlticore cable in condujt on a woodet or' :sonry wal1), :ie conduit is nlounted on a wooden wall such that the gap betr.een the colduit aud the surface is less than -1 times the conduit diameter. The conduit catr be metal or piastic. Where dre conduit is fixed to a masonry u,all the --rrent-canying capacity ofthe non-sheathed or sheathed cable rray be higher.
Rclcrcncc Method
C
rlulticore cables on
uooclcn or nrasonly u alll
a
(clippccl dilcct).
ibr cxanrplc. lnstallation Method 20 of Table 4A2 (single-core or
Cablc mouricd on a $ oodcn $ all so that thc gap betrvccn the cabie and the surface is less than 0.3 times the cable diarretcr. Where the cable is fixetl to or enrbcclded in a masonry wall the current-carrying capacity n.ray be higher. NOTE 2: 'thc term'u sonrr' i5 trk('n to include brirl$ork. concrctc. plaster and simiiar (but excludirg thcrnlaily insolating nlatcrials).
Rcfurcnce N{ethod D, tbl cxample. lnstallation Mcdrod 70 ofTabte 4A2 (rnulticore armoured cable in conduit or il cable ducting in tlre grourld). The cable is drawrl into a 100 n'lnr diametcr plastrc. ciirthenwalc or rretallic duct laid in direct contact with soil Ilaving a tllcnral lesistivity of 2.5 K.nr/W and at a dcprh of 0.7 m. The values given fol this method are those stated in this appeldix and are based oD conscrvatiVe iustallation paranretels. llthe speciflc installatiol pammeters are known (thcrn]al resistance ofthc glouud. grouncl aurbient tcmpclatu[e. cable depth). reference can be made to the cable manulhcturer or the ERA 69-30 seri!,s ol publications. which r.nay result in a smaller cable size being selected. NOTE 3:
l
\rith soil havirg a thernaL resisti\ ity of 2.5 Knr/W ard hrsherthal1 thc ralucs tabulated tbr Refcrcrce Method D
hc cunort-carryin-s cilpaeity tbr cables lilid ir) dir ecl contact
at
a.lepth ol'(l
T nr is
apploxinratcll
Relerence Nlethods E, F and G. nrulticorc cables in llce air).
tbl
l0'l,
exarrplc. Lrstallation Methods
3l to 15 of Table 4A (singlc-core or
Thc cablc is srippo ed such that thc total hext dissipation is not irnpcded. Heating due to solar radiation and other sourccs is to be takeD iuto accourlt. Carr-' is to be takcn that ratural air convection is not impeded. In plactice, a clearancc bctu,cen a cablc ald any ailjacent surlac!' of ill least 0.-l times the cable extemal diameter tbr multicore cablcs or 1.0 tiurcs thc cablc dianretcr lbr singlc-corc cables is sulicient to pemit thl] use of cuffent-carrying capacitics appropriate 1o llee air conclitions
7.2
Other Methods
Cablc on a floor': Ret'elence Method C applies tbl cLn]cnt,.ating purposes. Cable under a ceiling: This ilstallatioll rnay appc.u sirnilar to Retirencc Method C but bccause ofthe teductjon in natural air convection. Rel'crcnce Mefiod ts is to lla used lbr the current rating. Cablc trat systems: A pe bratcd cablc tray hils a regular pattem ofholes that occupy at least 30 % ofthe area of the base of the tray. Thc culrent-calrying capaciry lbl cables attached to pertbrated cable trays should be taken as Retircncc Mcthod E or F. Thc cuncnt-carrying capacity l'or cablcs attached to unperforated cable tmys (no holes or holes that occupy less tlrlD 30 'r; ofthe arex ofthc base ofthe tmy) is to be taken as Reference Mcthod C. Cable laddcr s)stem; This is u construelion uhich ottels a minin.trm of impedance to the air flow atound the cables. i.e. supporting mctal\&otk unclcr thc cables occupies less than l0 % of the plan area. The cunelt-calJing capacity 1br cables
o[
ladder systcnls should be'taken as Rcttrcuce Method E or F.
Cable cleats, cable ties and cablc hnngers: Cablc suppolts hold t[']e cable at intervals along its length and permit substantially courpletc ticc uir'flor around thc cable. The cunent-canying capacity fol cabie cleats. cable ties and cable hangers should be taken as Retercnce Method E or F.
Cable installed in a cciling: This is sinrilar to Rcl'crcnce Method A. [t may be r]ecessary to apply the rating t'actoi s due to highel ambient tcrrperatLiles that rliay nrise ir Jrnction boxes and similar mounted in tlrc ceiling. NOTE: Where a junction box in thr, ceiling is us.d lor lhc supply to a luminarle. $e heat dissipation liom the )uminaire rnay
fro\idc
higher urrbielll tenp!'[ttur.s lirdn pcr0']itted rl1 Tables
tenlperatlrre ll]ay bc bcl\\een
4DlA to,1J4A
(see aiso Regulalion 522.2.1).
40'C ir1d50'1.rnditrltinglactoraccordingtoTable4Bl
Ihe
must be applied.
General notes to all tables in this appendix NOTE 1: ( ulrent carrying capleitics arc tabulutcd lor nlcthods ol
installation which arc comnotly used lbr fixcd clcctrical installations. The tabLrlatcd capacilieJ arc l-or contrnuous steady-state operation ( I00 % load factor) tbr DC or AC of nominal licqucDay 50 z and trkc no accoLrDt ofhufiionic content.
NOTE 2: Table,lA2 itelnizes tlrc r!i.rcncc rrcrhod\ ol lrstalliition Io which thc tabuiated cunent-canJiDg capacities refcr.
TABLE 4Al
Schedule of lnstallation Methods in relation to conduclors and cables
-
Installation \l.rhod Conductols
Cable
Cable
Cable ladder.
trunking
ducting
cable lray.
systems*
systems
cable brackets
np
nP
luP
ruP
np
P
Pl
P
np
P
P
P
P
P
NiA
P
P
P
P
wrthorit fixings
('lippcd dxeat
slstclrs
Barc condLLctors
llp
np
Non-shea!hed cablc
lup
and crbhs
Shcnthcd
Nlulticorc
CondLrit
On
Support
irrsulators
wire
P
11p
np
N,A
P
NA
P
cablcs
(rncluding afmoLlred
ilnd l]lil]arul
Siuglc-.orc
P
insulai.d)
P np \rA
Pcr-rrittccl.
Not pcnuitt.d.
Nol Npplicable. or
+ includiug
nol ornially
Lrscd
in pructrce.
skiling tluuking and flush flool nlnkins
or duct5 : Non shcathed cabics a|e acccptablc if tirc t|urking systern providcs at ieast th!'degrcc ol proiection IPXXD o[ IP4X and tha cover cau onl! bc relno\ed by rnea s ol'it lool or a delibelate action.
lr
".-f.*
il
(including Reference Methods) TABLE 4A2 - schedule of lnstallation methods of cables for determining current-carrying capacity
installatiorl plactices but are indicative of the nlethod NOTE 1: I he illustralions are nor rntended to depict actual product o1 dcscribed.
NoTE2:Thei[staliatjona11drelelenccnlcthodsstatedalejn]inewitlrIEC.flofievcl.notalllnethodshaveaco[esponding tating lbt a1i cirble tYPes Reference Method to be used to determine capacitl"
lnstallntior Method Dcscription
Examples
Number
lml.--
Norl-sheathed cables in conduil ir a thelmally insulated wall with an inncr skin having a themral conductancc ofnot less than
WlmrK'
10
Multicore cable in cordnit in a thermally insulated wall with al ilrner skin
,
IE61^..-
having a thennal corductance ofnot lcss than L0
w1nrK
"
Multicore cable direct
lBdl-""-
3
ir /'--\
4
1r
u
iD a thennally insulated
wall witll an inne[ skin
havi11g a thctmal colductance
ofnot
less than
I0 W/mrK' Non-sheathed cables in conduit on a wooden or rltasoft) wal] or spaccd lcss than 0.3 x conduit dianeter fiom it
Multicore cable i[ conduit on a wooden or ]nasorry tlall or spaced lcss than 0.3 x conduit diametel flom
5
C-..-
lllll 1
'r ffir ll2j ll
9
e=i!!==ji,r
::'ir;E:i
t0 1t
B "
B
it'
Nor-sheathed cables ir1
cable ffurlking on a u'ooden ot masouly wall
B
h 6 - r.tLn horizoDtally h' 7 - rr.rn vcrtically
Multicorc cable in cable trunking on a wooden or nlasollry wa]l b 8 - run horizontally 9 - run verlicallyt" Non-sheathed cables in suspencled cable tmnking
B 6
Multicore cable
ir
suspeflded cable trunking
b
NoD-sheathed cables run
l2
in lrlouldirgs
;il,;;ii;; il.:;:;r"
"'
ir"r,l..+i i i, ,,ppri*L,,te. i,respecri\e or'irre f rcsence of
an i,1!cr1,rr
ba*ier or par.Lon
can be nruclr higher. L'he
,f,"
rnenrr..
""r.*1.r, under
air ro be p'-ror becr''t: ol lll( mllcrial ul colrslrucllu'r'rC r':"_rb'e -' used' .qui\ alenl to lnst llirtior Mcrhoils o or R(feren!e Mclhod B may be
re.r.riutl .'l l.l.'.lrJ. '',,r( ." a"r,rncJ it
*","ralll
cdlsidcftlifil:: l,:i
-
-laL('' \\ h'-
TABLE 4A2 (continued) Reference Method to be
Installation Method
Examples
Number
used to determine rurrent-carrving caPacity
Description I
11
.:
t5
...'.:
:
@[ -
- Gij.
',.@
l6
Non-sheathed cables in conduit or single_aore or nlulticore cahle
i
in architmve '
r
No]1-sheathcd cables in couduil or singlc_core or ]t'lulticore cable
@l
in wiudou lianlcs
'
Single-core or rnulticore cablcsl 20
- lixed on (clipped direct). or spaced less ihan 0.i cablc dianletcr lioln a lvooden or
C
'
)
masorry wall ' C
Silgle-core or multicore cabics: llxed directiy LlDder a wooden or masonry
2l
rHighrr
N\
cciling
lrn {rrdird
o..ur \ilh 1[is
dN6l.nl l.nrnerxtEs
i]shlhlr.i
m.tlt.d)
E, l- or G* Si[glc-core or ]nulticore cablesi
,7
(
- spaced
liom
a
ceilirg
Hr!h.r thrn nrtrr
rrcur
isalrd \
trh
aNbi.n(.n1f ctrrluir\
$r\ trrftlLiin$ nr'lhod)
23
Sirgle cole ol nlulticore cables: on unperlbrated ttay run horizontally or vefiicallY "
30
C with item 2 ofTable 4C
I
'
Single-core or multicore cables:
EorF
- on perlorated tray
3l
run
ho
zorltally or vefticallY'
r'
Silglc-core or lnulticore cables: - on brackcts or oD a wire mesh traY
32
EorF
rulI horizontally or vefticallY "r'
icted,Tlreambicnltenpel?irrcatthetopoltheverticalscctioncall higher wherc thc the Datelial ofconslruction and possible air spaces resislr\ it_v olthe cnclosurc is assumed 10 bc poorbecause ol ihcmal The g Lrsed' ma! be B VIe1hod Refirence 6 7 3 or constrxction is thelnally equivalcnt to lnstallation Methods be much
-. i
D. = lhc extemrl diamcler ofa multicore cablcl in trctbil or - 2.2 x the table diamelc| $hen rhtcc'singlc_corc cabl's are bound ir flrll-onnation laid are cor' cables when lhrec:ingle - x ihc cable diameicr
I
'
Still undcf crnrsidemlion in
ll
C
TABLE 4A2 (continued) lnstallation I\'Iethod
\umber
Description
E\amplcs
Relerence Method to be used to determine
current-carrying capacity
Single-sore or rnLrlticore cables: - spaced lnore dran 0.i tinres thc cable
33
}]. l, or Ge
dianrerer ftonr a wall
Single-core or multicore cables: - on a laddef
3,1
,,,.\
lq
Single-core
(w)@
35
ullicore cablc nrspelrdcd fiom
EoIF'
a suppod wire or harness
I
o!
4l
De
Single-corc or nrulticore cable in a building void "r' '
Non-shealhed cables in conduit irl a buildiug void irr masonry ha!ing a thernal resislivity rlot grcalcr dran 2 K.r]I/W''r
1
or-
(;
Bare or Don-shealhcd cables on insulalors
36
10
or
ot incor-porating
E
whcte
V < 20 De
1.5 Dc < use
B
Where 1.5 use
De: V B
Sirrgle core or multicorc cablc
i'
12
rur
De
scB
in .lasonry hr!,ing a ihcrnal resistilit), nol I K l1r,w '
grearor llran
l-_
t.
43
WhercljDcl\i
a builcliug void
Non-sheathcd eablcs in clrble ductiDg
Where 1.5 De < V
inlr buildirlg void
use
in nrasonry hari|g a themral tesistivity not gr.atcr lhan 2 K.nrW ' '
I
B
SiDgle-core or nNlticore cabLc
rr cablc ducting 41
h
D
Wlrcrc
a bLrililing void
in masonry Iaving a thclnial resisiivity Dot grcater draD 2 K.nr/W '
I
NoD-sheaLhed cables ir cable ductirlg
45
ir nasonry h:rvi
g a
1.5
use
Wherc
lhernulrcsisliviiy nol
1.5 Dc
De:
V
B
1V < 50
Dc
use B
greatcr than 2 K.Dr/W'r' Single-core or nllrlticorc cable
ir
46
Where 1.5 De < V < 50 De
cable ductillg
masony haviug a thcrDral resisli\,ity nol sr?rlcr rhan 2 K.rn/W ' r' ' iD
Sirgle-corc or nrulticore cablci - in a ceilirg void
41
- iD a suslrendcd lloor
''
bc nruch hish,Jr:
The thctors in Table 4C I mat h
rllo
be used.
D. - the e\tcrnal diarrclcr ol x nnrllicore cablel - l.l r fi. cable dixfr.l.r \r h.n lhree singlc core cabLes arc botrnd in lrelail. or - ,1 : the cablc di.rnrcr.r s hcn rlrr'cr :ingle-core cablcs arc laid in fidl lorrn.rlidl
D. = external dianicrer olconduir or \ertical deprh ofcable duclilrg.
usc B
Where
l5 De
B
De
TABLE 4A2 (continu ec Refereoce Nlcthod to be used to determinc
lDst:rllatior ]Iethod
\nmblrr
Dcsrription
Erilorplcs
currrnFcrrr)'ing capacitl
Non shcathcd cables 50
R
in flu\lr cabl,- irunking in the floor Nftrllrcorc
5t
Lr)
!rblc
B
llush cable trunkiig irr lh. fio,,I
Non-shcadrcd cables 52
B
in llu5h rnnrking'
Mulricole cable 5-l
in tlurh
B
t *ing'
Nor-sheathed cables or single-corc cables
5{
Nhcre
1.5
in eonduit irr aD unvcnlilaled cable channel
D;
run horizonially or
l
retically''r
use
"'
Non sh.alhed cables B
in conduit in an open or \entilatcd cable channel
55
in thc
floor
"'
Sheathed single-corc or rnulticore cable in an open or ventilated cable channel
56
rLrn
ffi F-ffi
Slr-qlc-corc or mullicorc cablc Llircct in mrionry hxVing a thcrmNl resisti\,ity not
t..Ht Itff
57
B
horizontilly or r€rti.ally "
gr.ller
ffi
rhan 2
K.
C
,W
- \\ rrlrout added mech.rnical prct!'cliol1 " " Srnglc core or multicore cablc dirc!t in nlasonry having a rhelnl l rcsisti\iIy nol grcalcr fian 2 K.Dr/W
5iJ
C
- \!rttr add('d mcchaDical prcteclion
"'
te g. enpDing)
r."or
'heathed
cables or single-core cables
in.ondlLit
59
rn
isonry having
8rc.rt!r than
Nlulti.ore 60
2
B
a thermal resistivit,v not
K.m/lv
"
cables
B
iD masorry having a dlerlllal resistnit) not
gr.ateI than
2
K.n/W
nru.h highcr
D! I I
exrcIlLl di,rnrct.r ol.orduil.
h. depth olrhc (hrnnel
For
is rnorc
nlullilorr .nblr lustLrll.d
rc(lucrion in .ulTclll-..r1yLng
xs
irrporlant th,rn lh. \,,idth.
Mcthflt
cflpicil!
jj.
us!'.ulTenl-calll-irg capacity fbr Rcfcrcnce !1cdrod
nd rhr Lfic
hrz.r!lduc tu
tlie.1L.ur11tLLLrron L,l
ts
Ll(brr\cxnbepr.\cnttd
forcrblcs hx\rns !ondu.(nr noI Srrealer lhtur l(, nnnr. lh. rurTent_canling capaciI m.r\ b. h]gh.l (excludes th.rnrnLL\ rns!Lhling
T
nnle xltr
DcaV B
TABLE 4A2 (continued) Reference Method to bc used to determine
Install:rtion N'lcthod Description
r-\rmples
cur
rent-carrying capacity D
FoI multicore armoured
Mukicorc a nourcd cablc in conduit or irl cable 1t)
rablc only
duciing in the ground
71
Shcathed. annourcd or muliicore cables difecl rn
D
the gromd:
72
- wiihoul added mcchanical prctcction (sec lrote)
Sheathed. annoured
or
ulticore cables direc! in
$e groundr
NOTE;
T)
- rvith added mechanical protection (e.g. cable
13
The nrelusron
ol dirccllv buried cables is satisirclory rvhele the soil rherlral rcsistilily ls of the odcr
o1 2.5
K.n W
For lo$er
soil rcsistilities. ihe curlcrrt-carrying capacity ibl directly buried cables is appreciably higher thalr lbr cablcs in ducts.
TABLE 4A2 (continued ' lnstallation methods for flat twin and earth cables in thermal insulation) Reference Method to be used to determine current-cartYing caPacitY
lnstallation Nlethod Description
ExrDrples
y_
100
$=
Installatiorl lnethods tb.llat t$ir and earth cable clippcd dircct to ll \\ooden.ioist, or touchillg the plasterboard ceiling sulface, abovc a plaslerboard ceiling $ith thcrmal insulation not exceeding 100 nnn in thickness ha\:i[g a n']irlimLrm U valLle of 0.1
Table 4D5
WimrK
lNtallation methods tbr flat twin and earth cable clipped direct to a woodenjoist, or touching the plastoboard ceiling surface. above a plasielboald ie.llng \\ ith rlrcrral insrrlalion cxcecLlirrg 100 rtlm
t0l
Tablc 4D5
irl thickness having a minimum U value ol' 0.1 WhnrK
lnstallaiior methods lbr flat twi[ a]rd !'ar1h cable in a stud 102
drertnal insulatiorr
\'itlt
a tninttl)lltn
llNtallation nethods lbl flat twin and earth cable ir a.tud w,rll $illr lhcrrnal rn(ulaliott \\tlh i lniDinlulll U value of0.I W/mrK with the eabL: not touchins the inner wall surface
103
whcrever praclicable. Regu laiion
\\all\\ith
U value of0.l W/m:K with the cable touchirg the inner rvall sufhce, or touching thc plasteftoard ccilillg surfhcc, ard the inner skin lrtvirtg 1r minimum U value of l0 Wn'trK
5
2I
9, BS
a cablc is to be 5
fixcd
803 5: Appcnd ix
C I
iD a posirion such that it
Table 4D5
will nol be covcred with therrnal insulation.
Avoldarcc of overhealing
Thennal insulalionr avor.ling risks. llR 162. tsRE.2001 refer'
]'able 4D5
o
f electric cables,
B ui ld
ing Regulations Approved Docunlent B and
TABLE 4A2 (continued lnstallation methods for cables enclosed in infloor cancrete troughs) Refer€nce M€thod to be uscd to dcterminc
lnstallation Nlethod
\umber
t)rscliDri0n
Erianlplcs
current-carrying capacitl
Cables supportcd on the \\ all ofan opcn r)r rcntilalcd infloor co|crele foLrgh \\ rrh spacin!
x!
tollo$ s: Shcathcd siDslc corc cables lll t'rec air (an\ suppo{ing metrl\!ork under $e c.lbles occupying lcss thar l0 9n olplan rrca).
tt1
J
-
Two or three cables vcrtically ore abo\e rhe other. Inininru distirnce bel$een ccble surtirces equal to fie o'eralL cable diametels. distance lionr ihe \\ill not lcss than l'r the cable diameter.
'
Two orihrcc cablcs horizontally
rith
EorF
spacing as
Cablcs in cncloscd rcnch 450 rrrrr *.idc by 300 nnn deep lnrininrufi dimensions) incllrding 100 ntttt cor eL
- l"u ro.r\.r
!-lc :or. r.ro <s r tlrsrr l:ces ofonc c.rblc diamctcr
scparatcd by a minimuIl1
EorF
ll8
tso sroups ofthrce single core cables ln trefbiltbnnation
One or
=
using rating factors in Table 4C6
Ore lo ,bur I aorc cable5 or orre to three cables of .l or.l corc. \\ rlh all cablcs scprralcd by a
rrilrinrulr 0i 50 |rnr Cables enclosed h an infloor concrete trough.l50 mm u idc by 600 nnn deep (minnnum dimensions)
ircludrrg i00 llnn cover Sir to t!\elre 5insle-core cables arranged in flat groups oltr o or thrcc on ihc \ cfiical trcnch wall u ith cables separated by one cable dianreter and a
nlirnnulr olS0 m r between
groups.
EorF 119 two to foltl groups oltlxee sh-qle-core cablcs in trefoil forrnation with a mirinum of50 nnn
b$\i'cen trefoil lbnnatiors.
tbur to cighi 2-core cables or tl'lree to six cablcs of I or 4 cores wilh cables separated by a minimum
oi75 mn.
All
r--
cables spaced at leasr
l5
nnn fiom trcnch wall.
using rating factors in Table 4C6
TABLE 4A2 (continued lnstallation methods fot cables enclosed in floor concrete troughs) lnstallation )Iethod Number
R!,lerence )Iethod to be uscd to dctermine
E\iDrpl!!
Description
curIcDt-cnrr'ling capacity
Cables encloscd in an infioor concrelc trough l dcep lnriDimum 600 nnn widc by 760
n
oo oo oo oo
121)
oo oo oo oo oo oo oo oo
&& cd cd && ooo ooo ooo ooo
dincnsions) including I 00 mln covcr. -['wclve
lo t\!cniy"1'o!$ single-core cablcs arranged
iu either flar tomation oftro or thrce cables iD a group \Lilh cables scpanted by one cable diameter and each cable group scparated by a ,ri11inum of50 nnn eirlrcr horizontally or v,rrricully
single-corc cablcs iu lreflil f'onnation \viih cach group or trelbil tbrnlation separatcd by nrinimLrm ol50 mnl either horizontally or
EorF a
vetically
to sixiccD I'core cables or six to t$,elve or,l cores with cables separated by a cables
eiglt
oll
nrirrirnulll oI
TS
mm eilher horizonlally or
vcrtically
A11 cables spaccd
at leasl25 mln from trench $all.
using rating factors Iable 4C6
ill
TABLE 4A3
-
Schedule of cable specifications and current rating tables Specitication
Specification lrumber Ellcctr'ic
BS 5467
tss 61,16
(wirhdra\n)
.\pplicable current Iating Trbles
ol 600r l00u V and 190013300
Conductor operating temperature
90,c
cables Th!mrosctting insulated.annourcdcablas
1b| volta.ges
BS 600.+
title
V.
I-leetric cabies PVC irsulated. non-arrnour-ed cables 1bt voltages up lo and iDcluding.l50i 750 V, for electric power. Iighling aDd internirl $ iring (fixccl installation).
4Dr..lDl.1D5
70
'c
Low ternpelature PVC irlsuhted and sheathed flcxible cable (flerible cablcs).
4F3
60
'c
Electric cables PVC insulaled. armoured cables for voltages o1600/1000 V aud I900i i300 V
4D3.4D,1.4H1.
70'c
Flectlic cables Themrosetling irsulated. amoured cables tbr voLtages o1600/ i 000 V and I900i 3300 V having low
4Ei.4E4
90'c
4El.4E2
90
4D2
70'c
4El.4E4
g0
4E1.4E2
90
1D2
i0'c'
4H4.4J3.4J.1
Retained hcrc
lbr lislorical pLlryoses
BS 6724
cmlssion ofsnroke and conosive gascs when atTcctL'd by 1'lre.
BSilll
hlcctric callles Thernlosetling insulatcd. nott_armoured up to and including 450,'750 \'. tbr clccn ic por c'r. lightiog arld irllemal wiring. aDd liaving low cnrrssi,on o1 smoke ancl eon!sive gases \ len atltcted by
"c
lxblc\ Lr !oltagcs
tirc.
trlccnic eablcs Spcciticutron lbr 300r500 V fire-rcsistant clcct|ic cables having lorv cnission ofsmoke and collosive
BS 7619 l
eases u,hen aflccte-d by
lirc -
Pa l: Multicore
cables.
tlectric cablcs Thcrnosetlius ins lated. armourcd. fircrcsislanl cables ol rated \ oltxge 600/ I000 \r having low
BS 73.16
"a'
cDrission olsmokc aDd cor-tosire gases \!hen affected by Jlrc. Specilicntion
Elcctlic cablcs
tss 7E39
- Ihe
rosetting insulatcd.
!VC sheathed. V
"c
unarDoLLrcd cablcs far u vollage of60011000
Llcctric cables 300/500 \ screeled elcctrjc cablcs having loir emission oIsnroke ar]d con-osi!e gases [ten affecled by- firc. t'or Lrsc in *alls. prrtilions arld building voids -
BS 1{4t6
nlulticore cables. Elactric cables Thclnrosctaing irsulated. non_aflroLucd cablcs \\ itli a voitage ot-600/ 1000 V for llxed itstallations. lralinr: low emission ofsnroke and corosive gases when allccted by lire.
;1E
BS iJJ9:
Electric Cables Thelinosctllng iusulaled. non-annoured. lire-resistant. sirclc corc non-sheathed cables ofratcd \oltagc 450/750 \'- haviug low enlissioo ofsmokc and cor-r-osive gases whcn altccled by fire.
4El
Elcclr'ic cables Lo$ voltage energy cables oftated volragcs up to and includil)g ,150i750 V (flexible cables).
4F
Lorv \ oltage energy cables ofrated voltages up to and including 450/750 V (1lxed installation)
.4U1. 4E
Mineral insulated cables and their temlinations with \olrage not exceedrng 750 V Part l: cables.
,lC
BS EN 50525-
)-rI
t_
t) )-)l
2-51. 2-82. .l- l
j-2
90'('
90
l. 4F2. 4F3
"c
"c lr0.c. 180 "c
60 "c.90
r.
r
BS EN 50525-2-
lr.34l BS EN 60702-1
*
l. 4E2
BS 8571
Elcct.ic cablcs
x Shcatll operaiing t.DrllcratLlre
-
a rated
I.
I
70'c.90'c
.tcl 105
"cxx
TABLE 4B1
-
Rating factors (Ca) for ambient air temperatures other than 30 'C lnsulation
Mineral" Thermoplastic
Ambient temperature'
.C
60
'c
70
thermosetting
.c
90
thermoplastic
.c
covered or bare and exposed to
thermosetting
touch
Bare and not exposed to
touch 105
70 0c
25
1.04
r.03
i.02
1.07
1.04
3i)
1.00
1.00
l.0t)
1.00
1.00
l5
0.91
0.9,1
0.96
0.9i
0.96 0.92
40
0.112
0.87
0.91
0.85
45
0.1l
o.19
087
0.78
0.8r1
0.84
50
0.58
0.71
0.82
0.67
55
0.41
0.61
0.76
0.5 7
0.80
0.50
0.71
0.45
0.7 5
60 65
0.6s
0.70
1t)
0 58
0.65
75
0.50
0.60
rJ0
0
4l
0.54 t).41
85
040
90
0.3 2
95
TABLE 482
-
Rating factors (Ca) for ambient ground temperatures other than 20 'C Ground temperature
.C
t
"c
70 .c
lnsulation 90
"c
thermoplastic
l0
t.10
1.07
t5
1.05
1.04
20
1.00
1.00
t5
0.95
0.96
l0
0.89
0.93
35
0. r34
0.89
,10
0.17
0lt5
45
0.7l
0.E0
50
0.63
0.7(r
55
0.5 5
0.71
60
0.45
0.65
65
060
10
0.53
.75
0..16
rJ0
0.18
TABLE 483 - Rating factors (Cs) for cables buried direct in the ground or in an underground conduit system to BS EN 50086-24 for soil thermal resistivities other than 2.5 K.m/W to be applied to the current-carrying capacities for Reference Method D 0.5
0.s
I
Rating factor ior cables in buricd ducts
1.13
ll Lll
Rarin!' frclor rin dircct brried cables
1.83
l.:n t.6l
1 tE
I,5
1.10
Thermal resislivity. K.m/W
NOTE
1: Thc rat;ng f'actors givcn have been arcragcd o\,er the rangc of
2.5
I
r.os
0.96
1.ll
090
conducl(rr iizes and types of instrllitron
0,. includcd in the relevant tables in this appendix. The overall acculacl of ratiDg l-aclors is s ilhin = 5
NOTE NOTE
2: 3:
Where more precise values are rcquircd ihey nra], be calculated by nlethods gi\ en in BS I r691BS IEC 60187). The mting factors are appLicablc lo dlrcts buried al dcpths ofup to 0.8
r11.
- Rating factors (Ca) for depths of laying other than 0.7 m for direct buried cables and cables in buried ducts
TABLE 4B4
Depth of laying,
Buried direct
In buried ducts
1.03
1.02
m 0.5
0.'l
1.00
1.00
0.97
0.913
1.25
{)95
0.96
1.5
0.9,1
0.95
1.75
0.91
0.94
0.92
0.91
0.90
0.92
0.89
0.91
2.5
TABLE 485 NLrDlber
-
Rating factors for cables having more than 4loaded cores
ol loaded cores
Ratins factor Nulnber of loaded corcs l'actor
5
6
1
l0
I2
t1
19
0.1)
0.67
0.61
0.56
0.53
0.5l
0.45
21
)1
30
37
44
46
.lit
0.42
0.40
0.3 9
0.36
0.34
0.33
0.jj
NOTE 1: The curlent-carrying capacity for a cable in the size r-ange 1.5 to 4 mmr. having more than 4 loaded coles. rs obtained try multiplying the cu ent-carrying capacity of a 2-corc. having the same insulation type. by dre i'actor selected flom this table. The cuffent-canJing capaciry lbr thc 2-core cable is that for the insta]iation conditioli to be used for the multicore cable. o/o of its current-canJing NOTE 2: If. due to known operatitlg conditions. a cole is expectcd to carry not mole than 30 capacity in the multicore cable it may be ignored for-dre purpose of detemining the number ofcor-es in the cable.
NOTE 3:
Il
duc ro known operating colditions. a core is expected to carry not more than 30 9/o of its rating, after applyirg the raring factor for the total number- of curenFcanling cores. it may be ignored fot the purposc ofobtajning the mting t'actor 1'or thc number ofloadcd corcs.
For example" the cuncnt-canying capacity of a cnble ha\ ing N loaded cores would nornally be obtained by lnultiplyitg the cunent-carrying capacity of a 2-corc. haviug the same iisulation typc. by the factor selected fiom this tablc fbr N co1es. That is I.l. : Irt. x C!\ rvhere:
I,lc is the cu cnr-carr)ing capacity ofthe mulricorc cable atter applying the ratil1g factor for the total nulnber of curent-canl ing cor'es I,1" is the tabulated crurent-cartying capacity ola 2-core cable. having the same insulation type as the cable C!\ is the rating 1'actor tionr Tablc.lB5 fbr the total ntttnber of curent-canl ing cores
Howcr er. if NI cot-cs in ihe cablc cart! loads \.vhich are not greater than 0.3 x It:c x capacilv can bc obtairled b\ using thc raling t'actor co espondingto(N M)cotes.
Cg
fiulti-core
t. the curent-canJing
' I,:. . C "r' calculation should be applicd betbre thc adjacert nulticore cable grouping factor. il applicable. tronr Tablc lc-l . The .10 7o rulc should not be lirrthcI applied to any adjacent cable grouping faclor calculations The nor srearcr than 0 -i
I
l,tc should *L greater ihan or equal to I. or l-," > l^ or l- C
16
as appropriate. d1\ ided
b)
lhe rele\ ant rating factor(s) C, that is
TABLE 4C1 - Rating factors for one circuit or one multicore cable or for a group of circuits, or a group of multicore cables, to be used with current-carrying capacities of Tables 4D1A to 4J4A 'lb be used rvith culrent-carryirrg
Number of circuits or multicore cables Item
Arrangement (cables touching)
I
2
3
4
5
6
7
Brurched in air'. on a
1.00
0.Et)
0.70
0.65
0.6t)
0.5 7
0.5,1
0.
1.00
0.85
0.79
0.75
0.73
0.72
1.00
0.88
0.82
0.71
0.75
L00
0.37
0.82
0.E0
0.80
capacities, Relerence
9
t2
t6
20
i2
0.50
0.,15
0.,1r
0._i 8
AtoF
0.12
0.71
0.70
0.70
0.70
0.-lt)
('
0.13
0.71
t).72
0.12
0.12
0.7 2
0.72
0.19
o.1t)
0.78
0.78
0.78
0.78
0.78
8
Method I
surface. embedded or enclosed 2.
Singlc layer on tvall
or'floor Single layer nLLlticore
or1 a
pedbrated hofizontal or vertical cable t[ay systcm 4.
Single layer' rnulticore on cable Iaddel systen
or-
cleats etc.
NOTE 1: l'hese t'actoN are applicablc to urliforr groups of!ables. eqtlally loaded. NOTE 2: Whcre horizontal clearances betwcen adjacenl cablcs excccd twice their overall diameter. no lating firctor need be applied. NOTE
3:
I-he same factols are applied tol - groups of two ol drree single-cor'e cables;
multicore cables.
NOTE 4: If a group corsists of both two- and thrce-core cables. the total nurrber o[ cables js taketl as thc nlrnbcr of circuits. and thc cofespondirg factor is applied lo the lables for two ]oadcd conductors for the tro cor-e cables. and to the Tables 1br three Ioaded conductors fol thc thlce-core cables. NOTE 5: Ifa gloup consisls ol/? single-corE cables it nray eirhel bc considercd
as
,/2
circr.Lits
oftwo loaded conducto|s or,/3 cilcuits ol
ihree loaded conductors.
NOTE 6: The ratil1g factot-s givcn have been avcraged o\'er the rangc of condlrctoI sizes ard typcs of installatioll ilrcludetl in Tables 4D1A to 4J4A LLnd the ovcrall accutacy oftabulatcd values is within 5 o/o. NOTE 7: For sorrc installations
a1)d lbr othcr rnethods Dot provided fbr in the above tablc. it rlay be appropriate to for specilic cases. see fbr example Tables,lc,l aud 4C5.
Lrse
lactor.s calculatcd
NOTE 8: Where cables having dille ng corlductor opel.rtirlg tenlperature are grorped tosether. the cLrrrent ratiog is ro be based uporr the lowcst operating teirperature ofany cable in the gtoup.
NOTE9: If, due to known
operating conditiolt. a cable is expected k) calry not more than 30 ignorcd for the puryose ofobtailling the ratirg factor fbr the rcst ofthe group. For-example, a gr-o[p
However'.
ifM
ofN
loaded cables would
norrally
require a groLrp rating factor
396
ofits
gr r.,rpzzl r'ating.
ofC" applied to the
it may be
rabLrlated
1,.
cables in the group car'ry loads which are not greater thar 0.3 C,l, arnperes the othet cables catl be sized by
usilg the gloup rating l'actor conespordi,lg to (N-M) cables.
--
o/o
TABLE 4C2
\\
ith
T\ ing e!.
-
Rating factors for more than one circuit, cables burjed direcfly in the ground Reference Method D in Tables 4D4A to 4J4A multicore cables
Number of circu ifs
ae
0.125
diameter
m
l).li
rn
0.5 m
0.30
0.s5
0.90
4,5
0.70
0.71
0.85
.l
0.6t)
0.60
0.7n
0.75
0t0
)
0 55
0.5 5
0.65
0 7(l
0.80
6
050
0.55
0.60
0.10
0.80
6)
11\
r_,
-rl l:
One cable
0
Multicore cal cablcs
NOTE
Cable-to-cable clearirncr r,r r
Nil (cables touching) 0.7 5
d
-
/';ll
e?
0,
c[
Values gi\en apply to rn installalioll depth o10.7 m and a soil themral resisri\i1y of 2.5 K.rr,rW. These ar.e alelagc valtrcs tbt thc r-ange ol calrle sizcs and types quoted lor Tablcs 4D4A to.1J4A. The proccss ofaveraging. to-gcther \\ i1h rounding otl'. can r'csltlt in sonre cases in en ors of up to +10 9;. (Where morc precise valucs ale requircd rh.'y nray bc calculated by nrethods gii'cn in BS 7769 (BS IEC 60287).)
NOTE 2: Irr casc ofa tllcmral rcsislivity lo*cl than 2.5 K.rr/W th. rating factors can. in gcncral. bc incr-cascd and cal be calclrirted by thc methods givcn iD BS 7769 (BS IEC 60287). _l'lirl
.
and the
i'or
firee
TABLE 4C3
- Rating factors for more than one circuit, single cables In ducts buried in the ground Reference Method D in Tables 4D4A to 4J4A (Mutticore cabtes in singte-way ducts)
\umbel of ducts
Duct-to-duct clearance (0) Nil (ducts touching)
0.25 m
0.5 m
1.0 m
)
0l{5
0.90
0.95
0.95
i
0. E5
0.90
0.95
.l
0.70
0. ir0
0.35
0.90
j
065
0.80
0.IJ5
0.90
(l
0.6n
0.1J0
0.li0
0.90
0.7
M
jla
,,J.1 I, - .rred b)
-
ulli!orc crbles
@ A \r/
NOTE
1
tll appl\ to an installation depth of 0.7 m ancl a soil thermal resisririty ol1.5 K.nl\\i. They are average valucs lbr tlte rangc of cable sizes and types quoted fbr Tnbles 4D4A to 4J4A. The process ol averasing. togethcr with rouuditlg o1]- can r-csult in sontt' cases in en ors of up to + l0 7.. (Where mor-c pr-ecise \ alucs arc required they may be cnlculatod by rrethods gir eI in BS 7769 (BS IEC 60287).)
: \'alues eir
NOTE 2: In casc of a thcrmal resistivity lo\\,er than 2.5 K.n/W the rating f'actors ciu. iu seneral. be increased and can be calculated by thc mcthods giren in IIS 7769 (BS IEC 60287).
L'h
TABLE 4C4 - Rating factors for groups of more than one multicore cable, to be applied to reference current-carrying capacities for multicore cables in free air Reference Method E in Tables 4DzAto 4J4A
-
Installation ]Iethod
ir
Table 4A2
Number of trays or ladders
Number ofcables per tray or ladder 1
2
I
lg: Perfbtated
-1l,\lJt
r\:A=441J'_ >20nrm :300mm
cable tray
4
3
See
itcm
i
6
9
ofTable 4C1
2
1.00
0.87
0.80
0.77
0.73
0.6u
3
l.0t)
0.86
o.19
0 76
0.71
0.66
6
1.00
0.84
0.7'7
0.71
0.68
0.6.1
I
1.00
1.00
0.98
0.95
0.91
2
1.00
0.99
0.96
0.92
0.87
3
1.00
0.98
0.95
0.91
0.
l1
systenls
(Notc 3)
l
'' :20
I Vefiical perlbrated cable tray
u5
mm
See item .l o Table 4C I
2
1.00
0.88
0
81
0.16
0.71
l
1.00
0.91
0.89
0.88
0.87
2
1.00
0.91
0.813
0.87
0.85
I
0.97
0.84
0.78
0.75
0.71
0.68
r,
2
0.97
0.8l
0.16
0.12
0.68
0.63
t.\ ;l.U
3
0.97
0.82
0.75
0.71
0.66
0.6l
6
0.97
0.81
0.73
0.69
0.61
0.58
0.70
l1
syslenN
(Notc,l)
Unpeftbrated cable tray
(dtj.-( t0 r!
systerns
.- u 20 n
,',.\,:-i.\,,:.\
!/r'/rrLl Cable ladder systeDN,
32
cleats, wire
33
mesh tray, etc.
of'lable
4C1
r.00
0.86
0.80
0.78
0.7
6
0.71
r.00
0.85
0.19
0.76
0.73
0.70
6
1.00
0.84
0.'7 7
0.7 3
0 6lt
0.64
I
1.00
1.00
r.00
1.00
1.00
2
1.00
0.99
0.98
0.91
0.96
3
1.00
0.98
0.9-7
(r.96
0.91
2 l
34
' -' :20 mm
l:
Scc iteln 4
1
]
/:':,1\:.\r; r i\::.\ '\1,\ '/ " > 20 mnr :30a mm
(Note 3)
NOTE
>3o0mm
Values given are average's t'or the cable types and range of cotductor sizes coDsidered in Tables 4D2A to 4J4A. The spread olvalucs is generally lcss than 5 9,o.
NOTE 2: Faclors apply to single layer groups of cables as shorvl above and do not apply when cables are installed in more than one ltryer touehiug each other. Values lbl such installatious may be sig[ificanrly lower and must be detemtined by an appr-opriare nretirod.
NOTE 3: Values are giver lor verlical spacirg betwcerl cable trays of300 mrr and at ieast 20 nnn betweeD cable
tr-ays and uaL1.
For closer spacing the factols sirouid be reduced.
NOTE 4: Values are gi\ cn lor horizonlal spaciog between cablc trays of 225 min with catrle tr-ays ntounted back-to-back. For closer spacing th.'litctors should be reduced.
398
TABLE 4C5 - Rating factors for groups of one or more circuits of single-core cables to be applied to reference current-carrying capacity for one circuit of single-core cables in free air Reference Method F in Tables 4DlA to zu3A
Installation Method in Table
Number of trays
4.4.2
or ladders
-
\unlber of three-phase
tril\
circuits per
or ladder
Use as a
multiplier
to rating for
I
-l
Tottching Perforated cable tmy systerns
I
0.98
0.9
2
0.96
0.8 7
0.81
3
0.95
0.8 5
0.78
I
0.96
0.IJ6
Three cables in
2
0.95
0.84
formation
32
I
I.0t)
0.97
0.96
33
2
0.98
0.93
0.89
.14
l
0.97
0.90
0.86
I
r.00
0s8
0.96
2
0.97
0.93
0.89
0.96
0.92
0.86
I
1.00
0.91
0.89
2
1.00
0.90
0.86
I
i .00
1.00
1.00
2
0.97
0.9s
0.93
0.96
0.94
0.90
: r-:--i:--:--:-:-i:--:-l
lt
tl :
>300mm
:
.:: r_i--_:--:1-::--::r
->
0.8 7 Three cables in
horizontai
formation
!
(Notc 3)
1
I
20 mm
Touching Vefiical perfbmted cable tray
ll
vertical
svstems
(Notc 4)
Touching Cablc ladclcr systcms. clcats. \\ irc
Three cables
nresh tlay. etc
(Note
l)
Perforated systenls
31
(Note 3)
Spaced
VcItical pcrforaled cable tlay
r-=.19--^^
3t
systc1lls
i
,
--ni225
"EJ
(Note 4)
:zue
i
rr|mia.
t-
L!_*
I
De
2 2D^
"
Cable ladder syslems. cleats. wir-e
,,
33
Three cables iIr
trefoil fonnation
Ue
32 > 300 mm
mesh tray. etc.
(Nore 3)
in
horizontal fornlatioD
34
>20mm
NOTE 1: Valucs given are averages fbr the cable lypes and rangc olconductol sizes considered in Tables,lD lA to 4J3A. Tlre spread ofvalues is generally less than 5 9'u. NOTE 2; Factors appiy to single layer groups oI cables (or h etbil groups) as shown abovc al1d do not apply whcn cables are installed in more than orlc layer-touchirg each other. Valucs tbr such installations may be significaltly lowet and must be dctcrmircd by ar appropriate nrelhod NOTE 3: \alues are giver tbr vedical spacing betrveen cable trays ol .i00 nnn and at leasl 20 mm between cable trays and wall. For closel spacing thc fictor_s should be teduced. NOTE 4: Values are given fbr l'lorizontal spacing betu,ccn cabl,.' Iays ot closer spacing tllc l'actors should be rcdlrccd.
]li
nrnr
\
ith cable tral r floLurted back{o-hack. Eor
NOTE 5: For circuils ha\ ing nlorc than ouc cable in parallel perphas!.cachrhrcepha.csetofcondLlctorsistobcconsidered as a circr.rit tbr-the pur.pose
t
ollhi.
1rble.
TABLE 4C6
-
Rating factors for cables enclosed in infloor concrete troughs (lnstallation Methods 118 to 120 of Tabte 4A2)
The ratin,c thctors tabulatcd b.'lo\\ relate to the disposition ot cables iliustrated in itcnrs I I tl to I 20 of lab le 4A2 and are applicable to tlte cln rellt-caffying capacities lbr Rel'erencc Methods E and F as given in tl]e relc\ ant tables ofthis appendix.
Rating factor
Installation method
ll8
lnstallation nethod
single-
singlecorc
,l singlecore
Conductor
core
cables,
cables,
cross-
cables,
or2
or 2 three- or
cables,4 t$o-core
cables,4 t$o-core
orl
two-core
four-core
cables,
threeor four-
cables
cables
cablcs, or 3 three- or
lbur-core
-3
sectional area
core
6 single-
6
cote
core
cablcs
cables
I
2
4
5
sirgle-
Installation method 120
119
8 single-
t2
t2
core cables,
or4
singlecore cables,
singlecore cables,
three- or
ttvo-core
ttro-core
or3
lbur-
cablcs,
three- or
core cables
r-
l8 singlecore cablcs, l2
core cables, 16
t\to-core
t$o-core
cables,
cables,
cables,
or9
or
or6
or6
three- or
three- or
fbur-core
lbur-core
cables
cables
l0
l1
S
S
three- or'
three- or
core
four-
fou
cables
core
core
cables
crbles
fou
6
,7
8
r-
9
24 sirgle-
12
(rnirr) 4
0.93
0.90
0.8 7
0.82
0.86
0.83
0.16
0.lJ
l
0.'/ 4
0.69
6
0.92
0.89
0.86
0.81
0.86
0.82
0.75
0.It0
0.13
0.613
-10
0.91
0.88
0.85
0.80
0.85
0.80
0.7
4
0.78
0.72
0.66
l6
0.91
0.87
0.8,1
0.78
0.83
0.78
0.71
0.76
0.70
0.(t4
25
0.90
0.86
0.82
0.7
6
0.8l
0.76
0.69
0.14
0.61
t).62
35
0.89
0 li5
0.ti l
0.7 5
0.80
0.14
0.68
0.1).
0.66
0.60
50
0.8u
0.84
l).79
0.14
0.78
0.73
0.66
0.7
t
064
0.59
70
0.8 7
0.82
0.78
0.12
0.77
0.72
0.64
0.70
0.62
0.57
95
0.86
0.81
0.7 6
0.70
0.75
0.70
0.63
0.68
0.60
0.55
0.68
0.61
0.66
0.58
0.51
120
0.85
0.80
0.75
0.69
0.73
150
0.84
0.78
0.7
4
0.61
0.12
0.61
0.59
0.64
0.57
0.51
185
0.83
0.17
0.13
0.65
0.70
0.65
0.58
0.61
0.55
0.49
240
0.82
0.76
0.71
0.6i
0.69
0.(t3
0.56
0.61
0.51
0.48
300
0.81
0.'7
4
0.69
0.62.
0.68
o.62
0.54
0.59
0.52
0.216
.100
0.80
0.71
0.61
0.59
0.66
0.60
0.52
0 57
0.50
0.44
500
0.7u
0.'72
0.66
0.5
rJ
0.6,1
0.58
0.51
0.56
0.4it
0.41
630
0.77
0.71
0.65
056
0.63
0.57
049
0.54
0.1"1
0.41
NOTES: I
.
The faclors in Table 4C6 arc applicable to groups ot' cables all of one size. The value of cuuent der-ivecl ll'onr application of ntaxinl D current to be ca[ied by any ofthe cables in the gro[p. If, duc to known opelating coltditiotrs. a cable is expccted to cnn) not nrorc than 30 %, of its g/r;r4rdrl t-atj1tg. it may be ignored lbr thc pLlpose ofobtainillg thc rating lactor for the rcsl ol the group. Where cablcs having difl'crent conductor operating tenrpe.atures are grouped togelher the currert mting should be llased on the appropiate faclols is thc
2. 3.
the lowest operating lenlperature 1.
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oC Sheath operating telnperarure: 70
Reference Methods E. F and G
Refelence Method C
(in free air or on
(clipped direct)
AC or DC
perforated cable
etc, horizontal
(]1
Three-phase AC
AC or DC
3 single-core
3 single-core
core cables
cables in trefoil
cables flat
touching or I
or I three-core
and touching,
or tbllr-core
horizontal or
cable
veftical
t\,vo-core cable
a
Single-phase
Three-phase AC
2 single-
.:ctlonal
a
oC Ambieflt temperature: 30
:.CARRYING CAPACITY (amPeres):
Single-phase
n
3 single-
3 single-core
core cables
cables flat and touching
2 single-core cables touching
or
1
two_core cable
in trefoil or 1
three-core
3 single-core cables flat and
by one cable diameter
veltical
or four-core
horizontal
cable 6
5
4
2
1
8
(A)
(A)
(A)
(A)
(A)
(A)
15
t1
19.5
16.5
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25
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33
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31
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44
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26
22
26
1.5
28
31
36
30
34
43
34
37
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40
45
49
56
45
52
60
5l
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11
5',7
48
51
6
1'7
65
82
69
84
95
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70
'77
92
109
92
t02
125
102
86
110
l6
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120
142
120
132
142
t62
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111
t'74
t47
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163
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169
181
215
182
198
2t3
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221
264
223
241
259
294
247
351
(A)
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32
296
249
264
3t7
26'7
289
309
286
303
364
308
331
402
340
353
lr)
346
416
352
3',77
454
388
321
400
rl)
440
3"1I
392
399
426
446
50'7
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434
451
496
49'7
565
514
466
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5s2
NOTES:
l. 2.
to be connected together at both ends' For single-core cables. the sheatlls olthe circLit are assumed be multiplied b) 0'9' values should tabulated the For bari cables exposed to touch.
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lCOeeen coruoucToRS AND SHEATH)
.
oC Ambient tempemture: 30
RRENT-CARRYING CAPACITY (amperes):
oC Sheath operating temperature: 105
Reference Method C
(in free air or on
(clipped direct) Single-phase
AC
rll
alea
OI
DC
2 single-core cables touching
or
Single-phase AC
Three-phaseAC 3 single-core
3 single-core cables in lrefoil
or
cables flal and
two-core
I three-corc
cable
or four-core
horizoDtal or
cable
vertical
l
cables
ill trefoi] or
I three-core cable
3 single-core
J single-core cables flal and
cables flat and
spaced by one cable diameter
touching veftical
or four-core
horizontal
cable
7
8
(A)
(A)
(A)
(A)
(A)
(A)
(A)
l9
21
24
2t
23
26
29
22
31
28
24
27
ll
26
29
33
l6
4l
35
39
49
33
43
38
64
51
44
47
54
46
51
56
20
24
26
22
25
28
32
24
30
33
28
32
35
31
26
40
35
11
45
38
43
4',7
54
42
47
53
60
50
56
6l
10
55
64
'7t
78
89
70 96
NOTES:
l. 2.
3.
I
cables touching
3 single-core
Juty
:
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5
2
.
Thrce-phase AC
or DC
touching"
I
Reference Methods E, F and G pedorated cable hay etc, horizontal or vertical)
a
59
8l
61 91
't6 104
87
96
105
120
t37
r57
127
107
119
137
115
t27
r40
154
119
150
164
178
204
166
171
187
220
184
200
248
203
2t6
2t2
230
2/2
228
24',7
266
304
251
323
370
307
260
280
331
279
300
334
400
33s
3s9
441
312
385
369
359
383
460
385
411
441
505
424
4t0
415
526
441
469
498
565
485
629
550
465
452
s96
500
530
55',7
544
5'/2
69',l
584
617
624
643
'704
connected together at both ends' For single-core cables, the sheaths ofthe circuit are assumed to be No mtiog factor for gro4ing need be appliedbe ascertained that the equipment connected to the conductor Where a conductor operut"s at a temp.rature exceeding 70 "c it should (see Regulation 512 1 '5 )' is suitable for the conductor opemting temperature
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APPENDIX 5 (lnformative) CLASSIFICATION OF EXTERNAL INFLUENCES This appendix gives the classilication and codification ofexternal infltiences. NOTE 1: The appendix is an extmct frorrl HD 6036,1-5-51. Each condition of extemal influence is designated by a code comprising a group of two capital letters and a numbel as
follows:
The first letter relates to the general category ofextemal influence:
A B C
Environment
Utilization Construction ofbuildings
The second letter relates to the nature ofthe extemal influence:
A B C The number relates to the class within each extemal influence:
I 2 3
for erample.
the code
{ {4 .ignifies:
A = Environment AA = Environment - Ambient temperature AA4 - Environment - Ambient temperature in the range of -5 'C to +40 'C
.
NOTE 2: Tlrc codification given in this appendix is not inlended to be used for marking equipment. The following key is for use when referencing the list ofextemal influences:
' r' '
May necessitate cefain supplementary precautions (e.g. special lubrication). This meals that ordinary equipment will operate safely under the described extemal influences. This means that special affangements should be made, for example, between the designer ofthe installation and the equipment manufacturer, e.g. for specially designed equipment.
L.
CONCISE LIST OF EXTERNAL INFLUENCES Radiated magnetic fi elds
AM8
-60.c ,40 "c -25'C
+5 qc
-5
+,10'C
'C
0c +5 "C -25'C +5
-s0
+5
'c
-5 'C
AEI AF2 Al3 AF4
Negligible
AM9
Atmospheric
AM2I
High-frequency etc. .
Intermittent
AM22
Conducted. . .nano.
Conlinuous
AM23
Conducted...micro...
"c
AM24
Conducled osclllatory
+60'C
AM25
Radiared HF
+40
"c
+55'C
AGI
Low
AM3
+40
AG2 AG3
Medium
AM4]
AHl AH2 AH3
Low
AN2
Medium
AN3
"c
L
High
ANl :2000
c
metres
@
F
c
o
't
LlJ
High
High
AP AD
ADI AD2 AD3 AD:l AD5 AD7 ,\D8
Othel hecha ical
AK AKl AK2
rlora
Negligible AP2
Negligible Drops SpEys Splashes
AP] High
No hazard
Hazai
Jets
Immersion Sxbmersion
AE AEI AE2 AE3
Forcign Bodies
AE4 AE5
Lighi dust
AE6
AJ
Negligible Small Very enall
Modemte dust
Hcav_a
dust
AQ
Lightning
AQI
Negllgible
ALL AL2
No hazard
AQ2
Hazard
AQ]
AM AMI AM2 AM3
Electro agnetic,.,
AR
Level
ARI
Signallingloltages
AR2
Voltage amplitude
AR3
AM4 AM5
Voltage unbalance
AM6
Induced
AM7
DC curent vohage
Power frcquency
lo*
v
i-
frequency
l! AC
D;ect
Hig]r
AS
ASl AS2
HigI
AS3
BA
Cdpabilitt
BAI
Ordinary
BA2
Childreo
BA]
.9
BA4
IE
BA5
.N
CA
CAI
t o
CA]
Coata.l
fith Earth
BE
None
BEl
No risk
Low
BE2
Fnc risk
Frequeni
BE3
Explosion risk
ContinuoN
BE4
Skillcd
BD BDI BD2 BD3 BD4
f
oc
BC BCI BC2 BC3 BC4
Erocuolion Nomal
Diffcult Crowded
Difficuh and crowdcd
CB Studue CBI Negli-qible CB2 Firepropagatio! CB3 Structural movenent CB4 Flcxible
.
A ENVIRONMENT: Code
External influences
En|it otltrentoI
Characteristics required for selection and erection of equipment
Reference for
information only
onditio i
Atnbie t tenlperann-e
Tte ambient tempemture is that of
the
ambient air wherc the equipment is to be installed
It is
assumed
ihat the
ambienr
tcmperatuc includes
the cfi'ects ofother equipment installed in the same location
The ambienl
temperature
to
be
considered for the equipment is the temperatul€ at the place where the equipment is to be installcd resulring
from the influence of all equipment
other
ill
the same location. \\'hen opeEting. nol taking into accounr ihe thcmlal contribution of the equipment to be installed
Lo*,er and upper limits of ranges of ambient temperaturc:
-60"c-5"c
AAz
40 .c +5
lncludes tempe ture range of BS EN 60721-3-l- class lK8. with high air temperature restricted to +5 'C. Part oftemperature range of BS EN 60721-3-4, c1ass,1K4. with low af tempcnture restricted 1() 60'C and hjgh air temperature restricted to +5 'C
.c Speciallv designed equipment or appropriate anangements"
25 "C
-5
.C
Pan oftenrperature range of BS EN 60721-3-3, class 3K7, \,r,i!h high air temperature restricled to
+5 'C. Includes pat ofremperature range ofBS EN 60721 3-4. class 4K3. with high air tcmperaturc reslricted to +5 'C Part oftemperature range of BS EN 60721-3-3, class 3K6, $,ith high air lemperature rcsticted io +5 'C. Includes temperature range of
BS EN 60721 3 4, class 4Kl. with high air lcmperature restricted to +5 .C 5 "C
-40 .C
Normal (in certain
cases special
prccautions may be necessary)
Pa
oftemperature range of BS EN 60721-3-3. class 3K5, \\,ith high air temperature restricted to +40
AA5
+5 .C +40 .C
Normali
"c
Identical to temperature range BS EN 60721-3-3. class 3K3
of
A ENVIRONMENT (cont.)
+5 ,C +60 "C
AA6
Reference for
Characteristics required for selection and erection of equipment
Exlernal influences
Code
Specially designed equipment or appropriate arrangements'
information only Part of temperature range ofBS EN 60721-3-3, class
3K7. with low air temperatue resfi icted to +5 'C and high air temperature restricted to +60'C. Includes tempemtule range of BS EN 60721-3-4. class 4K4 with low air temperature restricted lo +5 .C
50
AA8
"c
+40
Identical to temperature
-
-25 'C +s5 "C Specially designed equipment or appropdate arrangements"
'c
range ofBS EN 60721-3-3, class 3K6
Idenlical to temperature ofBS EN 60721-3-4, ctass 4K3
-
range
Ambient temperature classes are applicable only where has no influence
humidity
The average temperature over a 24 h period must not exceed 5 'C below the upper limits Combination of two mnges to define some envircnments may be recessary. lnstailations subject to tempemhfes outside the ranges rcquire special consideration
AB
Atmospheric humidiU
Air
Relative
temperature
humidity
a) low b) high
c) low d) hish
'c
ABL
60
Absolute humidity g/m' e) low f) hish
o/o
r00
+5
0.001
'7
Indoor and outdoor locations with exuemely low ambient temperatures
Appropriate armngements should be
Includes temperalwe range ofBS EN 60721-3-3. class 3K8, with high air temperatwe resEicted to +5oC. Part of temperature range ofBS EN 60721-3-4, class 4K4. with low air temperatue resticted to 60"C and high air temperature restricted to
+5'C AB2
40
+5
10
r00
0.1
,7
Indoor and ou(door locations with low ambient temperatures
Par of temperature range ofBS EN 60721-3-1. class
Appropiate arangements should be
3K7, with high temperature restricted to +5'C. Part of temperature range of BS EN 60721-3-4. class
4K4, with low air temperature restdcied to - 40oC and high air temperature restricted to +5oC
/o-* 5f"'*Doo\
f
uananv
I
A ENVIRONMENT (cont.) Code
AB3
Characteristics req uired for selection and erection of equipment
External influences
Air
Relaiive
temperature
humidity
a) low b) hish
c) low d) high
25
10
100
0.5
'7
Indoor and outdoor locations ambient temperatures
ritb
Iow
be
made"
)
-40
5
95
information only
Absolute humidity g/m' e) low f) high
Appropriate anangements should
AB4
Reference for
I
29
Weather protected locations haviflg
neither temperatue nor humidily control. Heating may be used lo raise low ambient tempemtues
Part oftempemture range of BS EN 60721-3-3, class 3K6, rYith high air temperature resricted to +5'C. lncludes temperature l.ange of BS EN 60721-3-4, class 4Kl, with high air temperature range restricted to +5oc
Identical with temperatue range ofBs EN 60721 3-3, class 3K5. The high air remperature restdcted to
+40.c Normalb
AB5
+5
+40
5
85
I
25
Wearher protected locations
Identical with temperature
temperature control
range ofBS EN 60721-3-3, class 3K3
Nonnalb
AB6
l0
+5
100
I
35
Indoor and oLrtdoor locadons
with extremely high ambient temperatues, infl uence ol cold ambient temperatures is prevented. Occurence ofsolar and heat radiation Appropriate anangements should be made'
AB7
t0
?5
100
0.s
)9
Indoor weather protected locations having neither tempeEture nor hunidity conirol, the locations may have openings directly to the open air and be subjected to solar radiation
Part of temperatr,fe range ofBS EN 60721-3"3, class
3K7, with low air temperature restricted to +5"C and high air temperatue restrlcted to +60'C. lncludes temperature range ofBS EN 60721-3-4, class 4K4, with low air iemperature restricted to +5"C
Identical to temperature range ofBS EN 60721-3-3, class 3K6
Appropriate arrangements must be made"
AB8
-s0
-40
r5
100
0.04
36
Outdoor and non weather protected locations, with low and high temperatures
Idertical to temperatue range
ofBS EN 60721
I
4. class
4K3
Appropriate anangements sbould be made'
--.
.!9
A ENVIRONMENT Gont.) External influences
Code
Characteristics required for selection and erection of equipment
Reference
for information only
AC AC1
s2 000 m
Nonnal6
AC2
rel="nofollow">2 000 m
May necessitate special precautions such as the application ofdcrutiry factors
NOTE:
For' some equipment special arrangemenls may be necessary at altitudes of I 000 m and above
AD ADI
Negligible
tPx0
BS EN 60529
Probabiliry of presence ofwaler is negligibLe. Location in which the walls do not genelally show traccs ofwatcr but may do so for shorr periods, ibr exanrple in the fomr ofvapour which good ventilation dries rapidly
AD2
Free-fallnrg drops
BS EN 60721-3-4, class 426
IPXI or IPX2
BS EN 60529
Possibility of veft ically falling drops Locatjon in which water vapour
BS EN 60721-3-3, class 327
occasionally condcnses as drops or where steam may occasionally be present
AD]
Spmys
tPx3
BS EN 60529
Possibility ofwater falliog as a spmy angle up to 60" ftom the vefiical
AD,I
Sflashes
at an
BS EN 60721 l-3. class
l28
Locations in which sprayed water foms a contiruous film on flools and/or salls
BS EN 60721 l-4. class 427
lPx4
BS EN 60529
Possibility ofsplashes froln any directiorl BS EN 6072I
Locations where equipment may be subjected to splashcd water; this applies,
tbr example.lo certair extenul lurniraircs.
I
3, class 329
BS EN 6T172I 3-4. class 427
construclion sile equipment
AD5
IPX5
BS EN 60529
Possibility ofjets ofwater liom any
AD6
BS EN 60721 l-.1. class
Localions where hose water is used rcgularly (yards, car-washing bays)
BS EN 6072I
tPx6
BS EN 60529
Possibility olwater waves Seashore locatiols such as pierc. beaches.
BS EN 60721 l-1. class 429
quays, etc
AD7
hnrnelsion
IPXT Locarions which may be ffooded and, or where the equipment is immcrscd as
follows:
'
.
AD8
Subnlersiorl
Equipment *,irh a heighi
of
less
than 850 mm is locaied in such a \r.ay that its lowcsr point is not nrore than I 000 Dnn helos, the suface of the water Equipment \r,ith a heighl equal to or greater than 850 nnn is locatcd such a way that its highest point is not more than 150 nrrn below the surface ofibe water
tPx8 Possibility olpcnnanent and total covering by water Locations such as swimming pools where electrical equipment is peflnanently and totallv covercd with water
d5o
lZl0
directioll
l-4. class 128
A ENVIRONMENT (cont.) Characteristics required for selection and erection of equipment Prcsence
IPXX
o.ff.)reig solid bodies
Negligible
see also Section 416
IPl]X
BS EN 60529
I
The quantity or size ofdust or foreign solid bodies is not significant
BS EN 60721-3-3. class 3S1
I
BS EN 60721-3-4. class
BS EN 60529
tPSX
Slnall objects (2.5 mm)
Presence of foreign solid bodies where the smallest dimension is nol less than 2-5 mm Tools and small objects are examples offoteign solid bodies ofwhich the smallest dimension is at ieast 2-5 mm
Very small obiects (1 mm)
45I
BS EN 60721-3-3. class 352 BS EN 60721-3-4, class 4S2
tP4X
BS EN 60529
Presence of foreigr solid bodies where the smallest dimension is not
BS EN 60721-3-3. class 353
less than I mm Mres are examples of
BS EN 60721-3-4, class 4S3
foreign
solid bodies ofwhich the smallesl dimension is not less than I mm BS EN 60529
IP5X Presence
ofdust
ifalust penetration is not harmflll ihe funclioning olthe equipment
I
10
IP6X Presence of dust if dust penetration is harmful to the functioning of the equipment
IP6X Presence of dust
Dust must not penerale equipment Prcsence of cottosive AF,1
AF2
ol polltning
BS EN 60721-l-1, class
l52
BS EN 60721-l-'1. class 4S2
I
BS EN 60529
I
BS EN 60721-3 4, class 3S3
I
BS EN 60721-3
l.
class
4Sl
The presence ofconosire ot polluting substances ot ahnospheric orisrn is srmificant lnstallations si;red bv the sea or near rndtrskral zones producing serioLls atmospheric nollution" such as chemrcaL works. cement uorks; this rYPe of Polluhon arises especrally in ihe prodnctioD ofabrasr\ e. insulating or conducfr\e
I
BS EN 60721 3-4. class:lS4
BS EN 60721-3 3. class
lC1
BS EN 60721-3 4. class
4Cl
BS EN 60721 3-3. class 3C2
BS EN 60721-3-4, class 4C2
dusts
Accordins to the nature ofsubstances (lor e\am;]e, satiqfaction oi saLt misr rest accordre to BS EN 60068-2-l t)
Irtermittent or accidental subjection to corrosive or polluting chemical substances being used or Produced Locations x'herc some chemical
nroducts are handled in small ;rlanhties and $here these Products ;a] come onl) accLdentall) into contact with electrical equipment; such conditions are fouDd in factory laboratories. other laboratories or in locations x'herc hYdrocarbons are used (boiler-rooms. sarages. etc ) Proteclion against conosion to equipment sPecificalion
I
BS EN 60721 3-3. class 3S4
sl.tbstafices
Neglisible
Atmospheric
I
RS EN 60721-l-3. class 3C3 RS EN 60721 3-4. class 4C3
I
AF4
Characteristics required for selection and erection of equipment
External influences
Code
Continuous
Reference
for information only
Continuousli/ subject to conosive or polluti g chemical substances in substaniial quantity. c.g. chcmical \\'orks Equipment specially designed according to the Daturc ol'substances
BS EN 60721-3-3. class 3C4
Nomal. c.g. household and similar
BS EN 60721-3-3, classes lM1.i3M2i 3M3
BS EN 60721-3-4. class 4C4
AG
AGl
Low seveity
equipment
BS EN 60721 3-4. classes 4Mt i4M2i4M3
AG2
AG3
MediuIn se\'erity
High se\.erity
Standard industr ia1
BS EN 60721-3-3. classes
equipnrent. $here applicable, or reinforced protection
3M4/3M5/3M6
Reinforccd proteclion
BS EN 60721-3-3. classes
BS EN 60721-l-4. classes ,{M4i4M5i,+M6
3M7iiM8 BS EN 60721-3-4. classes 4M7/4M8
fcrR,cDoJ
6+f;
r-lenanv
;
A ENV|RONMENT (cont.) Characteristics required for selection and erection of equiPment Household and similar conditions where ihe effects of vibralion are generally negligible
BS EN 60721-3-3, 3M113M/3M3
cLasses
BS EN 60721-3-4, classes
Nonnal
4Ml/4M2/4Ml
Usual industrial conditions Spccially designed equiPment or sPecial
BS EN 60721 3-3, classes 3M,1/3M5/3M6
arrangements
BS EN 60721-3-4, classes
4M4/4M5/4M6 Industrial installations subjecl to severe conditions Specially desi gned equipment or special affangements
BS EN 60721-3-3, classes
3M7i3M8 BS EN 60721-3-4, classes
,lM7i4M8
Ptesence ol /lora dnd/o|'nould
No hazad
gt'otth No harmfirl hazard from flora and/or mould growth
BS EN 60721-3-3. class
38l
BS EN 60721-3 4. class
4Bi
Nonnalb
Harmfui hazard fron flora and/or mould gro\\'th
BS EN 60721-3-3, class 382 BS EN 60721-3-4,
The hazard depends on local conditions and the nature offfora. Distinction should be made between harmful grouth ofvegetation or conalitions for promotion ofmould gro\r th
class 4B2
Special protection, such as:
-
incrcased de$ee
of
protection (see AE) snecial materials or protective coating of arangements to exclude flora fiom location
No hazard
No harmful hazard from fauna
BS EN 60721-3-3, class 3B1
Nolmalb
BS EN 60721-3-4, class
48l
453
External influences
Code
AL2
Ilazard
Characteristics required for selection and erection of equipment Hannful hazard from fauna (insects, birds, small animals) The hazard
BS EN 60721-3-3, class 382
depends on the nature ol the fauna. Distinction should be madc between:
BS EN 60721-3-4.
prcscncc ofinsects in hannfui quantity or ofan aggressive nalurel
-
ofsmall animals or birds in hannful quantity or of an aggllssive nature
pr,-sence
Protection may includc:
-
an appropriate degree
ofproteclion against penctration of forcign solid bodies (see AE)
-
suficient mechanical resistance (sccAG)
-
Precautions to exclude fauna from thc localion (such as cleanliness. use Pesticides)
-
special equipmeni or protective coating of enclosures
154
Reference
for information only
of
class 4B2
A ENVIRONMENT (cont.)
AM
Characteristics required for selection and erection of equipment
External influences
Code
Eleclroiidgnetic, electrostatic,
at
Lowfrequenq, eletholfiag1elic
Reference
for information only
ionizing
phenonena
(conducted ar rudiated)
Hamonics,
i
lerharmanics
Care should be taken that the controlled siruation is not impaired
Lower than table 1 of BS EN 61000-2-2
Normal level
Special measures in the design of the installation, e.g. filters
Complying with lable BS EN 61000 2 2
High level
Special measures in the design installation, e.g. filterc
AM-1-1
Conuolled
AM I-2 AM-1-3
le1,el
ofthe
I of
Locally higher than rable
1
of
BS EN 61000-2-2
Signalling |a ltages
AM-2-l
Controlled level
Possibly: blocking circuits
Lower than specified below
AM-2-2
Medium level
No additional requirement
IEC/TR 61000-2-l and BS EN 61000-2-2
AM-2-3
High level
Appropriate measures
AM-3-1
Controlled level
e.g. controlled by UPS
AM-3-2
Nomal level
Compliance with BS 7671 Chapter 44
Yo|tage
a
1pIiutde variations
Compliance with BS EN 61000 2 2
AM-4 AM.5
Pov,et
AM.6
Ind
[req enc! wriatia
+l
Hz according lo BS EN 61000-l-2
s
ced tow-f-equenc! valtages
ITU-T (Intemational
Refer to BS 7671 Chapter 44
No classification
High wilhsland of signal ard control
Telecormu cation Union)
systems of switchgear and controlgear
AM.7
Direcr cllnent in AC neb-orks (321.10.1.7) Measures to limit their presence and time in the
No classincalion
iI
level
cunenfusing equipmcnt or their vicinity Ra diated n o gn etic
I
,
,4.
fe
I ds
AM.8.I
Mcdium level
Nomralb
Level2 of BS EN 61000-4
AM-8-2
High level
Protection by appropriate measures e.g. screening and/or separation
Level4 ofBS EN 61000-4-8
8
A ENVIRONMENT (cont.) Reference for information only
Characteristics required for selection and erection
External influences
AM-9-l
Negligible
AM-9-2
Medium lerel
BS EN 61000-2-5
AM-9-3
High level
BS EN 61000-2-5
AM-9-4
very high level
1c\c1
BS EN 61000-2-5
High-litErcn() ele.trcDrug1eti phenonend ottdttcted, in.lLtLed ot radiotetl (tol1tit1ltous t)r
t
BS EN 61000-4-,1
Cond ded unidieclit,l.tI tftinsients ofthe
ti
runosccon(l
rc scule
Protective measures are lecessary
Le\el
I
Mcdiurr level
Protective lneasules arc necessary
Level
2
High level
Nonnal equipment
Lcvel
3
Very high level
High immunity equipnent
Level ,l
lrnpulse \rithstand of equipmcnt and oveFioliage protectivc means chosen taking into accounl the norninal supply loltage and thc impulse withstand category according to BS 7671
BS 7671 Chaplcr,l4
AM,22-1
Negligible levcl
AM-22-2 AM-22-3 AM-22-4
hri?ht)
Cand LleLl u ni Ll i retli ond I iillirecon,:l titne scale
fi an s ie n t.\ ol tt1iLl ose(
otkl
tu
Controlled Me.l ,,,n Hrsh
le\cl
t
le\el
I
le\el
I
BS 7671 Chapter 44
Chaptell4 Ca ttuhtc t !.1 osL i I I ator.t
nltti s i c
tt
AM-2,{ I
MediuDl le\ cl
Refer to BS EN 61000-4-12
BS EN 61000-,1-12
AM242
High lc\ cl
Refer to BS EN 602s5-26
RS FN
m255 16:2011
BS EN
(,
Radiared high fi'eqtrcntt phenontenct
AM-25-1 AN1
l5
l
AI\,1-15-3
Ncgligiblc le\el Medium ler,el
Nonnalb
High level
Reinfbrced lcvel
I
I c\ cl
2
Lc\el
3
BS EN 6r000-4-2
E I ec I rc.n a t i t Ll i sc h a rye s
AM-3t-t
Srrall lel'el
Normalb
Lcvel
I
AM-31-2
McdiLm Ievel
Nomralb
Level
2
AM-31-l
High Ievel
Noflnal"
Levcl
3
Reinforced
Level 4
AM-31
4
Very hlgh level
Special prcteciioo such as:
No classiflcation
Spaclngs from source
Jntelposition of screens, enclosure by special
mate als
456
Lc\cl
i000-1-l
A ENVIRONMENT (cont.) Exiernal influences
Code
Characteristics required for selection and erection of equipment
Reference
for information only
AN AN1
Low
lntensity < 500 WimrNomralh
AN2
Medium
500
AN3
Hieh
BS EN 60721-3-3 class
Wmr< intensity< 700Wm:
Appropriate arrangements must be
to 3K5
w/m: < intensity < ll20wml Appropriate arangements must be
BS EN 60721-3-3
700
Higher than class 3K5 BS EN 60721-3-4
Such arangements could be:
material resistant
to
ultraviolet mdiation special colour coating interposition of screens
Seisni
effects
AP1
Neglicible
Acceleration < 30 Gal (l Gal = lcrn/sr) Normalb
AP2
Low sevedty
30 Gal < acceleration S 300 Gal Under consideration
AP3
Medium scverity
300 Gal < accelemtion < 600 Gal Under considemtion
High severity
600 Gal < acceleration Under
Vibration whicb may cause rhe destruction ofthe building is outside
Frequency is not taker into account in the classification; however ifthe seismic $,ave resonales with the bullding, seismic cffects must be specially considered. In general, the frequency of seismic acceleration is belwecn 0 Hz and l0 Hz
AQ
Lighttling
AQI
Negligible
Nomalb
AQ2
lndjrect exposure
In accordance wilh Section,143
AQ3
Direct exposure
BS EN 62305-l
AR]
Low
Speed< 1m/sNormalh
AR2
Medium
AR
1n
s
< speed:i
5 m/s
Appropriatc
anangements should be made" High
5n s < speed < l0 nli s Appropriate arangements should be made'
AS1
Low
Speed S 20
AS2
Medium
20 nr./s < speed < 30 m/s Appropriate arangements should be made"
AS3
Hish
30 m/s < speed < 50 m/s Appropiate arrangements should be made'
AR3
3Kl
BS EN 60721-l-3 Classes 3K2
AS
rl/s Nomalb
B UTILIZATION: Code
External influences
Characteristics required for selection and erection of equipment
BA
Capability ol persons
BA1
Ordinary
Unirlslructed pcrsons Nonnalh
BA2
Children
Locations inlended for presence of children c.g. nrrsefies, infant schools. etc.Equipmentofdegrees of protectioncqlral to or greater than IP2XC. Imccessibility ofcqldpment $ith e\rernal 'urlace re.nperarure e\ceedilg ho'C
Reference
for information only
Inaccessibility of electrical equipment.
Limitation of lempcratue of accessible sufaces
not iD command of all their physical and/or intellectual abiliiies (sick persons. old persons)Acco ingto the naturc ofthe handicap
BA3
Handicapped
Pcrsons
BA,l
Insi[lcted
Persons adequatelyadvised orsuper!isedby skilledpe$ons toeDableLhernr"r'"rJdJ.ltsc-\$hicrr elecrri.ir) rn.r\ Lreale toperatL.g and rnarntenance (rrm Llccnic"l operdlrng dreJ<
BA5
Skilled
Equipmenl not havilg basic protection againsi direct contact wilh live parts admifted solely in locations which are accessiblc only to duly authorized persons u,ith technical
knowledge or sumcienl experience ro enable them to avoid danger which elect city may creatc (engineers and lcchnicians) Closed clcctrical operating areas BR
Electrical resistance ofthe human body Under consideration
BC
Contact ofpersons rvith f,arth pot€ntial Class ofequipment according to BS EN 61140
III BC1
Nonc
Persons in non-conductins \itrrations
BC]
Occasional
Persons \vho do not in usual conditions nrakc contact with exlraneous-conductive-parts or stand on condrcting
BC]
Frcquljnt
Persons
who are frequently in touch \\'j1h cxtraDeous pans or .tardr on .onJrrcting .err rcer
conduclr\e
Locations with cxtraoeousconductivc-pats.
either
numcrous or ofa large area Class ofequipmcnt according to BS EN 61140
O-OI
I
]I
III
A Eqripnrent pennincd
X
EqLLipment prohibiled
Y Peunifted ifused
as class 0
Pe6ons $ho are immersed in water or in long tenn pem1aDent coDtact u,ith metallic sunoundings and fbr whom the possibllily of intenupring contact is limited
BC4
Continuous
BD
Conditions ofevacuation in an emergency
BDI
Low deDsiiy
I\.4eta11ic
/ easy
exit
sunoundings slrch
as
boilers and tanks
Nornlalh
Low density occupation, easy conditions ofevacuation Buildings ofnormal or low hcight used for habitation BD2
Low dcEity,/ dimcult exil
BD3
High dcnsrty
Low density occupaiion, difncull conditions of evacuation High-rise buildings
/ easy exit
High der-'ry occupation. ca,y conditron. oleracr,at orr Locations open to the public (theatrcs. cinemas. deparhents
BD,l
High denslty./ difficuh ex(
High density occupation, difncult conditions of evacuation
High- se buildings opcn to thc public (ho!els, hospitals, elc-)
458
Ihrder considemrion
Code
Characteristics required for selection and erection of equipment
External influences
BE
Nature ofprocessed or stored materials
BEi
No signi6cani risk
Nomalb
BE2
Fire risks
Manufacture, processing or storage of flarimable malerials including presence of dust
Reference
for information only
Chapter42 Chapter 52
Bams, wood-working shops, paper f'aclories Equipment made ofmaterial retarding the spread offlame Arrangements such that a signilicant temperature rise or a spark within electsical equipment cannot initiate an extemal RF,3
Explosion risks
Prccesslng
or
storage
of
explosive
or
low-flash-point
Under consideration
materials including presence of explosive dusts
Oil refineries, hydrocarbon stores Requirements
for
elect
cal
apparatrN
for
explosive
atmospheres (see BS EN 60079),
BE4
Contaminalion risks
Presence of unprotected foodsruffs. pharmaceutics, and similar products without Fotection Foodstuff industries. kitchens: Certain precautions may be necessary in the event offault,
to prevett
prccessed materials being conlaminated by
electrical equipment. e.g. by broken lamps Appropriate arrangemcnts, such as:
protection against falling debris from broken lamps and other fragile objects
screens against harmful radlation such ultraviolet
as
infrared or
Under consideration
C CONSTRUCTION OF BUILDINGS: Code
External influences
CA
Constrrction materials
CAI
Non-conrbustible
CA]
Combustiblc
Characterislics required for selection and erection of equipment
Reference
for information only
\ornral BLrildings mainly constructcd
of
combustiblc materials
HD 60i64 4
,12
Wooderr buildings
Under consideralion Cts
Building design
CBI
Negligible risks
CBz
Propagation
offire
Nolmal Bulldings ofwhich rhe shapc and dimensions facilitate the spread of fire (e.g. chimney effect) High-rise buildings. Forced ventilation systems
lqupnrcnr rnadc
ol
HD 60364-4-42 HD 60164-5-52
marcrial rcrJrdrng the propagdlioD
of fire including {ires not originating from the
elechical
installalion. Fne barriers CB3
Mo\ement
Risk due to sttuctural movemenr (e.9. displacenrent)
Buildings
of considerable length or
erected
on
unstable
Contmction or expansion.joints (under considcraiion)
gound HD 60364-5-52 Conlra(lion ur erpdn'ion Jointr in eleLtricJl wir.ng CB4
Flexiblc or rnrstablc
Structures which are \r,eak or subject to movement (e.g. oscillation)
Flerible wiring
TeDts, air-support structures. l'a1se ceilirgs, rcmovable panil,ons. lnstdlldror. to besrru(lrrrall) .ellsupponint
HD 60364-5-52
Undcr considcration
,160
APPENDIX 6 (lnformative) MODEL FORMS FOR CERTIFICATION AND REPORTING lntroduction
(i)
The Electrical Installation Cefiificate required by Part 6 should be made out and signed or otherwise autltenticated by a skilled person or persons in respect ofthe design. construction. inspection and testing of the work.
(ii) (iii)
The Minor Electrical Installation Works Certif,cate required by Parr 6 should be made out and signed or otherwise authenticated by a skilled person ir respect ofthe design, constntction. inspection and testing of the minor work. The Electrical Installation Condition Repoft required by Part 6 should be made out and signed or otherwise authenticated by a skilledperson orpersons in respect ofthe inspection and testing ofan existing installation. as appropdate to their flrnction under (i) (ii) and (iii) above, have a sound knowledge and experience relevant to the natue of the work undertaken and to the technical standards set down in these Regulations, be fully versed in the inspection and testing procedures contained in these Regulations and employ adequate testing equipment.
(iv) Skilled persons will,
(v) Electrical Installation Certificates will indicate the responsibility for design, construction, inspection and testing, whether in relation to new work or fufiher work on an existing installation. Where the design, construction, inspection and testing are the responsibility ofone person a Certificate witl a single-signature declaration in the form shown below may replace the multiple signatures section of the model form.
FOR DESIGN, CONSTRUCTION, INSPECTION & TESTING
being the person responsible for the Design, Construction, Inspection & Testing of the electrical installation (as indicated by my signature below), particulars of which are described above, having exercised reasonable skill and care when carrying out the Design' Construction, Inspection & Testing, hereby CERTIFY that the said work for which I have been responsible is to the best of my knowledge and belief in accordance with BS 7671:2018, amended to ...........'.(date) except for the
I
I
departures, if any, detailed as follows.
(vi)
A Minor Elechical Installation Works Cerlificate will indicate the responsibility for design, construction, inspection and testing ofthe work described on the certificate.
(vii)
An Electrical lnstallation Condition Report will indicate the responsibility for the inspection and testing of an existing installation within the extent and limitations specified on the report.
(viii)
Schedules ofinspection and schedules oftest results as required by Part 6 should be issued with the associated
Electrical Installation Certificate or Electrical lnstallation Condition Report.
(ix) (x)
When making out and signing a form on behalf of a company or other business entity, individuals should state for whom they are acting. Additional forms may be required as clarification, ifneeded by ordinary persons, or in expansion, for larger or more complex installations.
I
ELECTRICAL INSTALLATION CERTIFICATE (REQUIREN,4ENTS FOR ELECTR
CAL NSTALLAT ONS . BS 7671 [IETWLRING REGULAl ONS])
DETAILS OF THE CLIENT
INSTALLATION ADDRESS
SEscRtpTloN aND ExrEttr oF THE tNsraLLATloN New
DescrjpUon of installatlont
of instatation covered by this ceruficate:
installation tr
Addition to an
existinqrnstallation Alleration to an exrstrnq rnstalra0on
ltJse cont nuation -rxtent FOR DESIGN
L-'l
t_J
see conunuation sheet No:
sheet f necessarv)
l/We being the person(s) responslble for lhe design of the electrical nsta lation (as indicated by my/our s gnalures below),.particulars of which a-re described ;bove, havlng exercised r;asonable skill and care when carrying out the design and addiiiona ly where this certificate app ies io an addltion or alteration, the safety of the exlsting installation is nol impaired, hereby CERTIFY that the design work for whlch l/we have been responsible is 10 the best of my/our knowledge and belief in accordance with BS 7671:2018, amended to ............. (date) except for the departures, if any, deiailed as follows: Details of depa.tures from BS 7671 (Regulations 120.3, 133.1.3 and 133.5): DetaiLs of perm ited exceptions (Regulation 411.3.3). wherelppli€be
The ertent of Iabilfty of the sLgnatofy o,
"ignatories
...
..
Eb
e nsk
a$e$mentG)m!$
be arached
r. rhis ce'1ir€!e
Risk assessmeni attached is lm ted io the work descr]bed above as the sublect of this Certficate
n
'*(Where there is mLrtual responsibility for the design)
For the DESIGN of the instal auon:
SignarL-e S'g_ature: .............
a
.......... .
...... .......... ... Des gner No
Daie' ....
Name (lN BLOCK LETTERS):
Date:
Narne (lN BLOCK LETTERS)r ......... ............... ...... .... ...... . Designer No
1
2'"
FOR CONSTRUCTION particulars of I being the person responsible for the construct on of the electrica insla lation (as indicated by my signaiure below), which;re descr bed above, having exercised reasonable skill and care when carrying out the conskuction hereby CERTIFY thai the construct on work for which I have been responslble stothelrestofmyknowedgeandbeielinaccordancewlthBST6Tlr20lS
amendedio...........(date)exceptforthedepartures,ifany,detailedasfollows: Details of departures from BS 7671 (Regulations 120.3 and 133.5)i
-he
extenl of lfabifrtyrcf the srgnaiory is lm ted lo the work described above as the subject ofthis Certificate.
For CONSTRUCTIoN of the installation:
Daier............... Name (lN BLOCK LETTERS): . ... . .................................. Constructor FOR INSPECTION & TESTING p,articulars I being the person responsibte for the inspectlon & test ng oflhe electrlcal installation (as indicated by my signature below), of which are descr bed above, having exercised reasonable skill and care when carrying out the inspection & testing hereby CERTIFY that the work for which have been responsible is lo the best of my know edge and belief n accordance with BS 7671 :2018, amended to .............(date) except for the depa(ures, if any, detailed as follows: Sionaturer.............................-...
Details of departures from BS 7671 (Regulatiofs 120.3 and 133.5):
lie
subject of this Certificate'
For INSPECTIoN AND TESTING ofthe installation:
.
. ...... .......... .""' lnspector Sionature: ....-..........-................- Date: -........-..... Name (lN BLOCK LETTERS): ............ NEXT INSPECTION lr\/Ve lhe designe(s), recommend that this installation is further inspected and tested after an interval of not more than .. . .. vears/months.
r
Address:........... ..........
... .
Address:............... ..
.. "
Address:..........
............ ..
"
-" " ;::;^^;:l
"
. r"ri.t.,..........g-
;::;::;:.
" .
i;iN;, .. ...... :
;^-i^^;:: "
i;iil,
..........
,ottag", u I uolr) '- "" " V No-rin"t Nominal frequency. fl' ... ,,' " ' H' Prosoecuve lault current. lp/'' ",' kA Erternal loop imPedance (Note:(1) bY ehquitY
'aiy
",q,,iy
-
ov
Z"12) o
:
BS (EN) .....................
Type.......
Rated current ......
.
..
A
^***,*a
Gs o"taitea on atta"f,"d "ct'"out") kVA / AmPs
Distribuiols facility
! Type (e.g. rod(s), tape etc)
lnstallation earth
electrode
""
" "'
D
I\,'laterial .........-.....-.........
"'
csa
" ",'"" """ mm
(.urrent Iannq Fuse / device rating or setting Voltage rating
.
of 0o1es .. ...... .... ....
:l:
:'::;ffiJ,i;;;i
"-"" "A
. .. '
"'V
Connecuon / continuity
veriiied
Rated residualoperating current Rated lime delay l\,4easured operating time ""'
(lr^)
I
""""
mA
"' """""" "'- frS
.,
ro it. is va,io o..ry when rhey are atached are part o, rhrs doc,rrrenr and rhis cerrilcate are atlached Resurts o'resl schedures ;:pections and
?il5n"?h5o"a"n"or"s l
Delete asaPPropdaie
"" ""
463
ELECTRICAL INSTALLATION CERTIFICATE Notes for the person producing the Certificate: 1 The Electrical Installation Cefiificate is to be used only for the initial cefiiflcation of a new installation
I
or for an additioD or alteratiol to an existing installation where new circuits have been inuoduced, or the replacement of a consumer unit/distribution board.
lt is not to be used for a Periodic lnspection, for which
an Electrical Installation Condition Repofi form should be used. For an addition or alteration which does not extend to the introduction of new circuits, a Minor Electrical Installation Works Certiflcate may be used.
The 'original' Ceftificate is to be issued to the person ordering the wort (Regulation 644.4).
A,
duplicate should be retained by the contmctor.
2
This Certificatc is only valid
if
accor.rpanied by the Schedule of Inspections and the Schedule(s) of Test
Results. The signatures appended are those ofthe persons authorized by the companies executing the work ofdesign, construction, inspection and testing respectively. A signatory autho zed to ceftify rnore than one category ofwork should sign in each ofthe appropdate places. The time inten/al recommended before the first
pe odic inspection must be inserted.
The proposed date for tl]e next ir]spection should take into consideration the ftequency and quality of maintenance that the installation can reasonably be expected to receive during its intended life, and the period should be agreed between the designer, installer and other relevant parties. The page numbers for each of the Schedule of Inspections and the Schedule(s) of Test Results should be indicated, together with the total number ofsheets involved. The maximum prospective value offault current (IpD recorded should be the greater ofeither the prospective value ofshort-circuit current or the prospective value of eafth fault curretrt.
ELECTRICAL INSTALLATION CERTIFICATE GUIDANCE FOR RECIPIENTS (to be appended to the Certificate) This safety Certificate has been issued to confinn that the electrical installation work to which it relates has been designed. constructed, inspected and tested in accordance with Blitish Standard 7671 (he IET Wiring Regulations). You should have received an 'original' Cefiiflcate and the cortractor should have retained a duplicate. Ifyou were the person ordering the work, but not the owner ofthe installation, you should pass this Certificate, or a full copy of it including the schedules, immediately to the owner The "original" Certificate should be retained in a safe place and be shown to any person inspccting or undertaking
further work on the electrical installation in the futui'e. If you later vacate the property, this Certificate will demonstrate to the rew owner that the electrical installation complied with the requirements of Bdtish Standard 7671 at the time the Certificate was issued. The Construction (Design and Management) Regulations require that, for a project covered by those Regulations, a copy of this Certificate, together with schedules. is included in the project health and safety docurnentation.
For salety reasons. the electrical installation will need to be inspected at appropdate intervals by a skilled person or percons, competent in such work. The maximum time interual recommended before the next inspection is stated on Page I under'NEXT INSPECTION'. This Cefiificate is intended to be issued only for a new electrical installation or for new work associated with an addition oI alteration to an existing installation. It should not have been issued for the inspectior and testing of an existing electrical installation. An'Electrical Installation Condition Repoft' should be issued for such an inspection.
I
I
This Certificate is only valid ifaccompanied by the Schedule oflnspections and the Schedule(s) ofTest Results.
ficrR,c\od /o+ -J
f;
_---
uremnv
I t
.',.-,-=
N w o RKS CE EI I I l-cflr E BS76/1.[ E,l \^ 11-\:].4':r---- ' : ,REouTREVENTS FOR EL EC lR CA. *sio-ioio*i', not ln"ruo" $te provisior o' a rew c rcurt *oit i't]i"rr ". To be used only for mino|, M r NO
R ELECT
R
I
cAL
I
N
srAL LAr o I
"t""tr,"u,
L-l TN-C-S 1. Syqtem eanhrng arrargeneni' TN"S
L.l llLJ
BS(EN)... .. .... ..
Live -
Live . .. ..
"'
. """
ms
""" """
" Ratinq
" """ ""
""" """' p'rih falllt loop lrnpedance: Z'
... ' l\"lo
^'^"i_"- -"e'rrad DisconnecUon tinre
Tvpe
Llve - Earth
A
MO
-
'-
"
'A
MINOR ELECTRICAL INSTALLATION WORKS CERTIFICATE
Notes for the person producing the Certificate: The Minor Electlical Installation Works Certificate is intended to be used for additions and altemtions to an installation that do not extend to the provision of a new cir-cuit. Examples include the addition of socket-outlets or lighting points to an existing circuit. the relocation of a light switch etc. This Cetiflcate may also be used for the replacement of equipment such as accesso es or luminaires, but not for the replacement ol distribution boards or similar items. Appropriate inspection and testing, however, should always be caried out irespective ofthe extent ofthe work undefiaken. MINOR ELECTRICAL INSTALLATION WORKS CERTIFICATE
GUIDANCE FOR RECIPIENTS (to be appended to the Certificate) This Certificate has been issued to corfinn that the electrical installatioll work to which it relates has been designed, constructed, inspected and tested in accordance with Bdtish Standard 7671 (the IET Wiring Regulations). You should have received an 'original' Certificate and the contractor should have retained a duplicate. Ifyou were the person ordering the work, but not the owner of the installation, you should pass this Certificate, or a copy of it, to the owner. A separate Cefiificate should have been received for each existing circuit on which minor works have been canied out. This Cefiificate is not appropriate if you requested the contractor to undertake more extensive installation work, for rvhich you should have rcceived an Electdcal Installation Cefiificate. The Certiflcate should be retained in a sale place and be shown to any person inspecting or undeftaking futher work on the electlical installation in the future. If you later vacate the propefty, this Certiflcate will demonstrate to the new owner that the minor electrical installation work canied out complied with the requirements ofBdtish Standard 7671 at the time the Certificate was issued.
I
Examples of items requiring inspection during initial verification A11
items inspected in orderio confiun, as approp ate. conpliance $ith the relevant clauses inBS 7671.
The Iist of jterrs is not exhaustive. Numbem itr bmckets are Regulation references.
EXTERNAL CONDITION OF INTAKE EOUIPMENT (VISUAL INSPECTION ONLY)
. . . . . .
Ser.rice cable Service head
Eafihing auangement
I
Meter tails
I
Metering equipment Isolator (wllere presenl)
PARALLEL OR SWITCHED ALTERNATIVE SOURCES OF SUPPLY
.
Presence oladequate arraDgements where genemtor to operate as a switched altemative (551 6)
t
Dedicate
.
(ss r .7)
I 2 3
Correct connectior ofgenelator in palallel (551.7.2)
Cornpatibility of characteristias ofmeans ofgeneration (551.7.3) Means ro provide autonatic disconnection of genemtor in the event of loss of public supply system or voltage or fiequency deviation beyond dec)ared values (551.7.4)
4
Means to prevent connection of generator in the event of loss of public supply system or voltage or tiequelcy deviation beyond declared values (55I 7.5)
5
Means to isolate gererator tiom thc public supply system (551.7.6)
AUTOMATIC DISCONNECTION OF SUPPLY
. .
Protcctive earthingr'protective bonding affangements (411.3; Chap 54) Prescnce and adequacy
I
ol
Distributor's earlhing arangement (542.1.2.1: 542.1.2.2), or irstallation eafih electode arrangernent (s42.t.2.3)
2 Earthing corductor and connections (Section 526; 542.3;542.3.2:543.1.1) 3 Mair protective bonding cotrductots and connections (Section 526:544.1;544.1 2) 4 Ealthing/bonding Iabels at a1l appropriate locations (514.13) .
Accessibi)ity
I 2
of
Earthing conduclor contreerions
All protective bondirg connectiors (543.3.2)
. FELV requile[rerts
satisfied (411.7; 2111.7.t)
OTHER METHODS OF PROTECTION (Where any of the methods listed below are employecl details should be provided on sepamte pages)
BASIC AND FAULT PROTECTION where used. confiruation that the requirements are satislied: ' SELV (Section 4l'1)
. . .
PELV (Section 414) Double insulation (Sectiol,112) Rcintbrced insulation (Seclion 412)
BASIC PROTECTION:
. . . .
Insulatiou of live pails (416.1
)
Barriers oL enclosutes (416.2:416.2.\) Obstacles (Scction 411: 111.2.1..411 .2.2) Placirrg out of reach (Scction 417: '117.-l )
FAU LT PROTECTION:
. . .
Non-conducting location (418.1) Eafih-free local equipotential bonding (418.2) Electricai separation (Section4l3t 418.3)
ADDITIONAL PROTEGTION
. .
:
RCDs not excecding 30 mA as specified (415.I ) Supplementary bonding (Sectior 415; 415.2)
SPECIFIC INSPECTION EXAMPLES as appropriate to the installation
DISTRIBUTION EQUIPMENT
. . .
Sccurity offixing (11,1.1.I ) lnsulation ollive pafis not damaged during erection (416.1) Adequacy/secrn ity ofbariers (416.2)
Suitability of enclosures for IP and fire ratjngs Enclosures not damaged during installation
(
(rt 16.2; 421.
134.
l.
L6;
421 .1
.201 526.5)
l)
Presence and et'fectiveness of obstacles (4 I 7.2)
Coinponents are suitable according to nralufacturers' assembly instructioos or literature (536.4.203) Presence of
nain switch(es), linked where required (462.1.201)
Opemtion of main switch(es) (ftinctional check) (643.10) Manual operation of circuit-breakers and RCDs to prove functionality (643.10)
Confinnation that integral test button/switch causes RCD(s) to trip when operated (functional check) (643.10) RCD(s) provided for fault protection, where specified (41 1.4.2041 411.5.2; 531.2)
RCD(s) provided for-additional protection, $,here specified (415.1) Confirmation overvoltage protection (SPDs) provided where specified (534.4.1.1) Presence of RCD six-monthly test notice at or near the origtn (514.12.2) Presence ofdiagrams, charts or schedules at or near each
dist bution board, where required (514.9.1)
Presetrce ofnon-standard (mixed) cable colour warning notice at or flear the appropriate distribution board, where required (514. l,+) Presencc ofalternative supply v'aming notice at or near (514.15)
I I 3 .1
The origin The metel po'itiun- if remole flom origirr The distributior board to which the altemative/additional sources are connected
Al1points ofisolation ofALL soulces ofsuppl_v
Presence of
tcxt inspectionrecommendation label (514.12.1)
Presence ofother required labelling (Section 514)
Selcction ol protectivc device(s) and base(s); corect type and rating (411.3.2; 411.4, .5, .6; Sections 432, 431. 43,+)
Single-pole protectivc devices in line conductors only ( 132.14.1; 530.3.3; 643.6) Protectior against mechanical damage where cables enter equipment (522.8.1; 522.8.5; 522.8.1 1) Protection against elcctlolnagnetic effects where cables enter ferro[ragnetic enclosures (521.5.1)
Cotrfirmation that ALL conductol connections, including connections to busba$, are correctly located in tenninals and are tight and secure (526. l)
CIRCUITS
. . .
. . . ra8
Idertilication of conductors (514.3.1) Cables cor:rectly suppofted throughout (522.8.5: 521.10.202)
Exanriration olcables for signs ofmechanical damagc during installation
(5
22.6.1; 522.8.1:522.8.1)
Exarrrination olinsuiation of live parts, not damaged during erection (522.6.1; 522.8.1) Non-sheathed cables protected by enclosure in conduit, ducting or trunking (521.10.1)
Suitability olcontainrrent systems (including flexible conduit) (Section 522)
Correct terl]perature raling olcable insulation (522.1 l: Table 5l'1) and nature ofinstallation (Section Adcquacy of cables tbr culTent-ca[yillg capacity \\ ith regard lbr the n pe 521)
prolectiotr (434 5) Adecluacy ofptotective clevices: type and fault current lating tbr l'ault Presence and adequacy of c il cuit prctective conductors (4ll i 1i 5'li' l)
Coorclinationbetweenconductolsandoverloadprotectivcde\ices('1331:5332'l) of installation wirirlg systems and cable installation methods/pmctices with Iegard to the B/pe and nature arld extenlal influences (Section 522)
protected against damage Cables cotcealed under floors. above ceilings, in walls/partitions, adequately (522.6.201. 522.6.202. 522.6.203. 522.6.204\
I
ptovisioll ofadditional protection by RCDs having rated residual operating curent (lln) not exceeding 30 mA
I 2 3 4 5
For all socket-outlets
ollating (32 A) or
less. unless erempt
(41l 3'3)
(411 3 3) SuppLies tbr mobile equipment not exceedirg 32 A rating for use outdoors
I I I
I
F'or cables concealed in walls at a depth ofless than 50 mm (522 6'202' '203)
(522.6.202; 203) For cabtes concealed in walls/partitions coutaining metal parts regardless ofdepth supplying luminaites within clomestic (household) pren.rises (411 3 4) Circuits
Pr.ovision of lire baniers. sealing arrangements so as to minimize the spread Band tl cables segregated/separated from Band I cables (528 1)
I
I
offire (Section 527)
CabJes seglegated/scpar ated tiom non-electrical services (528 3)
Termination of cables at enclosures (Section 526)
I Connectiolrs under no undue strain (522.8.5; 526 6) 2 No basic insulation ofa conductor visible outside enclosure (526'8) 3 Conncctions of livc condttctors adequately enclosed (526 5) ,+ Adequatcly connected at point of entry to enqlosure (glands, bushes
I I I I I
. . . .
etc.) (522.8.5)
Suitability of circuit accessories for extemal influences (512 2) Circuit acccssories not damaged during erection (134 1
1)
(132 14'1' 530 3 3; 6436) single-pole tlevices lbr switching or protection inline conductors only stationary equipment Adequacy of connections, ilcludilg cpcs, within accessories and at ljxed and (Section 526)
ISOLATION AND SWITCHING
.
Isolators (462; 537 2)
I 2 3 4
I
Presence and location of appropriate devices (Section 462l. 531 2 7)
Capable of beirg secured
ir
the OFF position (537 2 4)
Corect operatior vcrified (functional check) (643 10) by location and/or duable The lnstallatiol, cilcuit or palt theleofthat will be isolated cleally identified marking (537.2.7)
5warlli[g]loticepostedinsituationwhereliveparlscalnotbeiSolatedbytheoperationofasingledevice (5t4.l1.1; 537 t.2)
.
Switchirg off tbr mechanical mailtenance (Section 464; 53732)
1 2 3 4 5
Presence ofapproprjate devices (464.1; 537 3 2)
Acceptable location
-
Conect oPeratior verilied (l'Lrnctional check) (643'10)
I
I
I
I
durable marking The circuir or paft thcreof to be disconnectetl clearly identified by locatiot and/or 537.3 2.3; 537 3.2.4)
Emetgency su'itching/stopping (Section 4651 537'3 3: 537 4)
I 2
I
state iflocal or remote from equipmert in question (537 3 2 4)
Capable ofbeing secured in the OFF position (464 2)
(
.
I
I
Presence ofappropdatq dcviccs (465'Ll 517'3 3:537 4)
I
(53: -l'l'61 Rcadily accessible tbl operation iillele danger might occtlr
I
3 4 .
Corect operation verified (functional check) (643.10) The insiallation. circuit or paft thereofto be disconnected clearly idenlified by location and,/or durable markinir (537.3.3.6)
Functional s\ irching (,+63.1;537.3.1)
1 2
Presence of appropriate devices (537.3.1.1;537.3.1.2)
Corrccr operation verified (functional check) (53 7.3.1.1 ; 53j .3.1 .2; 643.10)
CURRENT-USING EQUIPMENT (PERMANENTLY CONNECTED)
.
. . . ' . . .
Suitability of equipment in remrs of IP and fire ratings (416.2;421.1;421.1.201; 526.5) Enclosure not danaged/deteriorated during installation so as to impair safety (134.1.1)
Suitability for the environrnert and extemal influences (512.2) Security offixing (13,1.1.1) Cable entry holes in ceilings above luminaires, sized or sealed so as to restrict the spread
Provision ofundenoltage protection, where specified (Section 445) Provision ofovelload protection. where specified (Section 433; 552.1) Recessed luminaires (downlighters)
1 2 .
Coffect type ofla[rps fitted (559.3.1)
lnstalled to minimize build-up ofheat (421.1.2; 559.4.1) Adequacy of working space/accessibility to equiprnent ( I 32. 12;
PART 7 SPECIAL INSTALLATIONS OR LOCATIONS Particular requirements for special locations are fulfilled.
470
5
1
3. I )
offire (527.2)
SCHEDULE OF INSPECTIONS (for new installation work only) for DOMESTIC AND SIMILAR PREMISES WITH UP TO
A SUPPLY
1OO
NOTE 1; This tbtnr is suitable lol marv tvpes ol smaller iDstallarion. nor erclusi\'el\' donlesric.
All items inspected in order to confirnr. as appropriate, compliance u ith
the relevant clauses in BS 7671. The list
of
items and associated examples rvhere given are not exhaustive. NOTE 2: Insen
10 indicatc aD inspection has been canicd out and the resulr is satisfafiort. or N/A to indicatc that thc inspection is not applioable to a pafiicular item.
'/
Item No l.{t
Outcome
DESCRIPTION
See Note 2
I'\T}:RNAL CONDITIO} OI' I\TAKE EQt]IPIIE-\-T (\'ISLAL I\SPECTIO)I OILY)
IL
l.:
ri !..1
t5 16
lsolaror 0vhcr. !rcscn0
1.0
tt
PARAl,l,trI,OR S\}ITCHED ALTERNATIYE SOURCfS OF SUPPLY Adcq u le an an-senrents $h.r i . scncratiDs sct operares ds r sNitehed altem.dle
22
Adcquale arangenrents Nhere a gcncrlins set opemres in parallel
3.0
AL'IO\TATIC DISCOT\"r-IC IIO]I
:.r
Presence and ndcquart of carthing and protec6 e br)nding .rrangemcn ts: . Distributols carthing amrrgement (5:tl.1.l.l j 542.1.2.1)
. IbulhtioD
cltr1h
{lth
ro llic public sulrp lv
(5
5
1
.6)
the nnblic supDl! (551.?)
OF SUPPL]'
clcclulc (\ huc rpf l jcabl.)
(5 11.
I
I l)
. Eadil1g conduclor and courections. inclxdin-q a.ccssibllity (5,12.:lr 5.1:.1.2) Main prorccllyc bonding coDductors and conneclions. inchrdnrg acccssibilir) (11
.P(
l.l.l.:r
543.3.2. 544.1)
is,on olsatirv cLccrricaL cxrthirs bondiirg labcls at aLla1)frofrar.lo.dtnntr (51,1.11)
. RCD(s)pro!idcd lbr laullprolcction(411.+.204:.11 I 5.3) .1.0
.l.l
R \Sla Plla)I I( t I()\ Prcs.n..and.deqr.c\oInrenn'rerropro!idcbaticprotedion(pR\enrn,nrncont..rwthlivcpar()Nithinrhc
.lnsul0rioD
olltrc l)ars..-q. cofdl. kIS .oDplerelr .olckd uilh dunbl. in{llling nul.rirl
(116
l)
. Aaders or enclosures e.g corcctIPrating(416.2)
5.0
\DDt
l.l()\\t. PRO .]( ItO\
i.L
hr\,
rd
rn,l rlli(ri\en$r ol rdrliliun!lprotLition mrthod\: 30 nrAoper.tirg curent (4l5.lt Pat 7). SuDplclncntnry bondins (.115 2r P.fi 7)
. RCI)G)nol crcccding .
ltcn
8.14 ofthis schedule
6.U
oTHf
6.1
Presence and effectiycoess olmethodswhich givc both basi( and f{ull protection: . SILVsvste . inclrdnrrJrhcsourccandassociatedcircuits (Section 414)
PEIV
R
Nlf'IH()DS OI PROTT]C',
scc
s!sre1n.
n'.ludin!
O)J
nre softce and
rssoc rcd circuits (Section 4l:l)
I)oublc or reinforced inNlation i e. Clas II orcquiral.nr equipment and !rsociated circ{its (Section,+l l)
'
. Eleerical seprration tbr
one irem ofcqldpmcnt e.g. shaler $pDlv unit (Section.+13)
7.0
CO\SLTMER U\IT(S) i DIS]RTtsUTION BOARD(S):
7.1
Adcquacy ofucces and
1.1
Conrpon.nrs.rc
7.3
Presence of
7.1
l
7i
$Li
rorkl.g
rpacc lbr ilrnN ofelectrical equipment iicluding slitchgcar ( 132.12)
ble ac.ordarg to a\senrblr manulactlrcr's iistruotioDs or literature (536.4.103)
lirked nra$ s$rch(es)
(.+02. 1.201 )
aDd dll iteDrs ofequiunent (462.:) Suitahilirr ofenclosurc(s) tbr IP and firc ralniss (:ll6.2r:121.1.6i,+21.1.201r j26.j)
aIoG fo' evcry cl,nuil or gro!'p olcncuits
471
CO\St:\lr Protecrion
R L
\lTrS) DISTRtttLTIO\ BO.\RD(Si cotrtinucd
rsiinn nlecliuical
lLL
damagc $herc cabtcs cnter cqui[ncDr (522.8.1: 522.8.5: 522.8
,1''1
ConlinnalioD rhar
7.3
A\oidaDce olherring ctleds $here.ables cnter ieromagneti. enclo$res e.g. stccl (521.5)
con(lucro, connecLions are on..Lirt,,-. located in teminah and n.e tigt,t
Sclection of rcr!.ct Npc and rarjnss ofcircuit prorectj\." 1.6: Sections.l3l. +lli 537.1.1.1)
a""i"".
ro.
ou"."u."rt
.11
7.]l)
Presencc ofappropriate circuit chArts, warning atrd
.P(
otler
n r,lrecrrc
1S:O.t;
1,tr
"nJEut[-rc"t[n
r-I3I
notices:
isio. ol circuit chans schcdule\ or equilalcDt tarns ofirtormadon
(5 t4 9) . Waariig notice oJ nrethod of isolation whcre Iirc pajls not clfabic ofbejng isotatcd by a single . Periodic inspeciion and tesring noticc (514 lt.l
dflie
(514.1l)
)
. RCD si\rnontH) .
rest noti.er whcrc reqxircd (51.1.11.1)
AFDD sir-montlly rcsr nodcci \vherc requned
'\hming
notice ofnon-srandard (miredl colours ofconducror prescnt (51.1.14)
7.1 l
Presercc oflabcls to
8.0
CIRCUITS
ildiqle
thc puTosc
ot$\irdrse.f
aDd
prorechc
devices (5
r4.iirsl4f)
rl.1
^dcquac},ofcoId!cnFbl..,.",.t-".;
3.:
Cnble i,rstallatn r Derhods snltable for tlre tocation(s) and erteruat influeiccs
tSecG 5,2)
8.i
Scgregriiofu'sep.mrion olBand I (EL! ) and BaDd 1l (LV)circtrils. and clectrical and
li .l
Cxbles.orecrly eLe.tcd
und
m||lrted
85
Pu
t.6
Nor sherllrcd crbl.s cncl6.d rlronghonr nj corduir.
8.1
Crbles conccal.d undcr
ision of1lr. hririe,s.
t"" 6:s,
""""b.6""L*"
tlnoughoul. \rnh prolc.tion agaiNt ebrasior (S".rio,,, S: r.
-.Zr
ierhig rm.g.henrs \here ncccss.rt (:17.2)
lllor.
aLx e ccit,ngs or in
d,rcrtDs oL rl1nrkirrq (5t 1. t0.
\.a s tadilitnls.
t: 516 8)
adcquarelr
frorcctcd isarr\l danige 1j:l6.10t. jtt.6.t0t. j::6:01jtt 6.20t) C(nnlucnn's corccth nlenriil.d b!.olou. Ictdnlg ornumb.ing (S.crnnr 5l,t) Prclencc. adequacy.nd corred tcmrjnation of
pr
otecrile .onductoF (.+ll.3.l. tr 543.1)
li l0
( rblcs
s.l
No basi. insularion ofa coDdu.ror risible onBide enclos le (5:6.8)
lJ
I
ll
3ll 8.ll
0d conductos ..n.ccll! &!mc(.d. cnrkDcd
Slngle lrolc dc\
A.c.s$i Irro\
i..\ nr $\ndrirg
rnd Nilh no ur(tne nrecb.njcrt
or prol..rjon iD lrre condu.td\ ontv ( tt:.1.1.
e\ nor d.rnagcd. s.. ure rr rrred. corrcctr! .on,kcred.
inor oladdilnDrl prcre.rlon icquir.Denls
{irablc for
t:5lL
l,1i6t
e{rcnral inttrenccs
ii \xris prllitjons .o j jnirg njctll po,r, ,.gu.at",, nr acptr,l-.Fnralcircuitssupplyinslmnlaircswlrliidomestic(househotd)prcmises(al1.3.4) Prcsencc olappropriatc dcriccs for holxtion and
including:
.
NlcoDs
'
EDrer
ofswilchirg off
iir
ol---6:
r-
o:
r-
(5:i
and curenr_usiig equiprr.,,t t+O]. r,
ftt:.t
t
+)
CURRENT-USING EQUIP]\{ENT (PER\,IA}ENTLY CO\NECTED) Equipmcrl nor damaged. securety fixed and snimble for e.t.,"nt inft,cn""s
9l
Pror
9..1
Irsnllcd to nrirnnize fic btrild{p olhear
ror
Ad..lurc]
ol o!erload and or undcr\ottiec protecrion
of workingsface.Acccssibitity
r0.0
LOC-{TION(S)
r0l
l0
11.0
OTHER PART
CO,\"I{t\I\c
m--\ RCD prcteclio! for all
7
L\i
and resrricL
(
t:+.ir I +tO::
e g. r'o..nraring n,n"r,ines.
ile
to equjpmenl
spLearl oi fire
S
t::l
tr,"qunals;ti*,
t421.1.4:s:C,
,aa:.
ss:t
)
(lj2.l1 jt3.l)
A BATH OR SHO\IER
(SICTION
701r
circuits. cquipnlent s!itabte for tbc zones. supplem"ou.y
t"ra,"g (r"i,"* *quir"AE;
SPECIAI,I]\STALLATIONS OR I,OCATIONS
Lirt eli other speci.l lnslollatior5 or locatiors prcsent. il arr {Rec.rd scparret!
Name (Capitats) 472
(4llX)
Dreclmnical maintenance (Section.16.lj 5l?.3.2)
9l
l.l
e r
gcncr'. s\l.itcltnrg (.165. I : 5 l7.1.I )
. fireiiehrer s s\iitdres
I
::
witching correcth toc;ted
. Funcrioml *litcfiing. tar conrrol ol pais ot rle ijrstrlt.rion
9.0
secr o,
Cables co0cellcd in walls ar a dcpth oflcss rhan 50 mm (522.6.202: 521.6.20j)
. (ablcs conc.rlcd
8.5
:r r ,]: r r : ::
Ll.t)
rlot crc.edjfg -ll.A tor usc onldo.r\
.
rt
ltmA:
trv R( D not c\.eednrg
. So.kel-oullets rarcd n ll A.r lc\. urless c\crrpr t.tr . S!pfllcs for nx,bile cquifln.rr \ jth . cu,Enl fur1ns
s*i,, tS."i*;:Or
Signature
rhe..r,,l,;;i.;ri"@
Date ..................
ELECTRICAL INSTALLATION CONDITION REPORT SECTION A. DETAILS OF THE PERSON ORDERING THE REPORT
SEcTroN c. DETAILs oF THE INSTALLATIoN wHlcH ls rHE suBJEcr 0F THls REPoRT
n..
L^er
oi.lrrpii".
.rp".i."t
Estimated age of wLing system .. ... ....... .years Evidence of;dd tions ialterations lnslalaton records available? (Regulation 651 1)
secrrbu o,
exrrrr
years YesD NoE Not apparent E lfyes, estmate age """ YesE NoE . - Date of last inspection "" "" "
"""""
"'
(date)
IHD LtMtTATloNs oF lNSPEcrloN AND TESTING
Extent ofthe eleclrical installation covered by th s report
Ope
aliola
l-tal,o'"
n(lLd lg ll^e 'easors (see paqe 10 ... . .
.
.
) ........ ............
r.Jt.irrg;.,;i;Ji;ilir;;il.;;;;;;til;;;i;;
with BS 7671i2018 (rET n.," o".n rr',[a *tr,, "ccordance Wlring Regu atons)as amended t0 ... ... . ... . ir, ul]d" i"ors, in roof spaces and generallywth n the fabrlc ofthe blrildlng or It should be noted that cabtes conceateo wttrtn irunflrg rn; "l;or prior to the inspecuon An nspection should be underground have not been inspected !nless specic;ly agreed between the clienl and nspeclo r equipment. elect cal housing other Ioof space an accessible made within SECTIOi'I E. STJMIVTARY OF THE CONDITION OF THE INSTALLATION
ir, i..p""tl.
Overallassessment *An
ofthe nstallation
in te.ms of its suitability for continued use
SATISFACTORY / UNSAT SFACToRY" (Delete as approprate) that danqerous (code C1)andior potenlially dangerous (code C2)conditons have been dentified. indicates unsatisfactory assessment
SECTION F, RECOIMI\4ENDATIONS l/ we recommend thai Where the overa lassessmeni of the suitabiity ofthe installation for continued use above ls stated as UNSATISFACToRY, a mattel of u lge ncy. up on as (code C2) are acted dangerous' any obse rvations c assiled as Dargel present' (co de C1) ot Potentially (code Fl) tn;esggation w thout detay ts recom me nded for observations ide ntified as 'F ulher investgation rcquied' observ;tlons classified as lnpravenent recomnended' (code C3)should begven due considelation sL
I I I
I
hle.t to the necessarv remedlal action beinq taken, I / we recommend that the installation|s further inspected an
SECTION G, DECLARATION (as indicated by my/our signatures ttWe, oeing ttre personls) responsible for the inspection and testing of the electrical installation when carrying out the inspection and care skilland reasonable having exercised ririich ire described above, i.i"iri, "r that the information in this report, including the observations and the attached schedules, provides an accurate testin;, hereby declare
p.itiirrl"
asses-#ent oithe condition ofthe etectrical installaiion taking in6 account the stated extent and limitalions in section lnspected and tested by:
Nare Siglalure
.........
D
ofthis report.
Report authorised for issue bY: (Capitars)
Signalure .....................
.
For,on behalfof
Postion ........... Address . .................. Date
Dale ............
.
sEcTloN H, ScHEDULE(S) .... ... . .schedlle(s)ol nspecuon and .. ....
.sched ule(s) of test resulls are attached The attached sched; e(s) are part of lhls document and lhls Ieport is va d only when they are atlached to t
473
SECTION I, SUPPLY CHAMCTERISTICS AND EARTHING ARMNGEMENTS Eadhing Number and Type of Live NaturE of Supply Parameters
arranqements
TN,C N TN.S tr TN.C.S E
ACn 1-phase 2-w re
2-phase.3w re 3'phase 3-wlre
tr tr
TT ]T
Supply Protective Device
Conductors
3-phase 4-wire
DCE
!
n tr tr
2-wire 3-wire
E
other
E
Confirmation ofsuppy po aritv
Nominalvolage, U/Uolr).......................V Nominal frequency,
n
fll
. .................. ........ Hz
Prospective fau t currcnt,
lp/a
Externalloop impedance, Z"
!
12) by
Type
........... ...... kA
l2l - '
Q
Rated
currenl ....................A
enquiry at by neasurcnent)
E
other sources ofsuppy (as delailed on attached schedule)
SECTION J, PARTICULARS OF INSTALLATION REFERRED TO IN THE REPORT ll4eans of Earthinq
Details of lnstallation Eafth Electode (where applicable)
Disiributols facility
tr
lnstallation earlh eectrode
tr
o
Resistance to Earlh
Main Prolective Conductors
Eanh'rg
coldLclor
lli,4atenat
Ivain orotective bondho condu.lors
ii;;;,:;;:;;;;;t'i,;:,a-;;-'" To waler installation
pipes
To lighlninq protection
n
........ ...
csa ......................mm/
rr2
I
To gas instalation
E
...
| .. I'/ate'iar
To other
l
pipes
f
lTooil
nstallation
pipes
Conneclion / cootinuity verified
E
verilied
n
Connection / continuity
E
To
structurclsteel
E
Specfy
Main Switch / Switch-Fuse i Circuit.Breaker / RCD
rriinn
Loaation
CLrpnl
BSTFN]
Fuse/devceratingorsettng ...........A Voltaoe €iino . V
A
lf RCD main switch Rated res dual operating currenl Raled ilme delav ...........
(l^,)
.....................mA
..
ms
l,'leasured operating t me
No of po es
SECTION K. OBSERVATIONS Reler ng to the attached sched ules ol ifspection and test results. and subiect lo the limitalions specifled at the Extent and limitations af inspection ard lestlrg seclion No remedial action s required
OBSERVATI0N(S)
E
The fo low ng observalions are made
E
{see below):
rncrud'sch'dure GI{ence,as
CLASSIFICATION CODE
one ofthe followifg codes, as appropiate, has been allocated to each ofthe observations made above the insta lat on the deqree of uroency for remed alaction. C1 - Daiger prcsent. Risk of injury. lmmediate remedial action required
C2
Polenlally dangerous - urgent remedialaction required
- lmprovement recommended F - Furlher nvestiaatiof req! red wthout delay
C3
to
ndicate tothe pe rson(s) respo nsib e for
CONDITION REPORT
Notes for the person producing the Report:
1
This Report should only be used 1bt reporting on the condition of an existing electrical installation. and [ottbr the replacenent of a consumeL unit disttibution board. An instaliation which was desi.gned to an earlier edition ofthe Regulations and *,hich does not full-r,corrply rvith the current edition is not necessarily unsat'e for continued use, or requires upgrading. Onll dal.rage. deterioration. defects, dangerous corditions and non-compliance with the requiremenls of the Regulations, rvhich may give rise to danger, should be recoldecl. The Report, normally comprising at least five pages, should include schedules ofboth the inspection and the test results. Addjtionai pages may be necessaly for other than a simple installatiol and for the'Guidance for recipients'. The numbcr ofeach page should be indicated, together witl'r the total number ofpages involved.
The reason fbr ptoducing this Repofi, such as change of occupancy or landlord's periodic maintenance, should be identified in Section B. Those elements ofthe installation that are covered by the Repofi and those that are not should be identified in Section D (Extent and limitations). These aspects should l'rave been agreed with the person oldering the repofi and other ir]terested pafties before the inspectio[ and testing commenced. Any operational limitations, such as inability to gain access to parts ofthe installation or au item ofequiplnent, should also be recorded in Section D. 5
The naxiururlr plospective value
olfault currelt (Ipl) recorded should
be the greater ofeither the prospective
value of short-circuit current or the prospective value ol eafih fault cufient. 6
Where au installation has an alteruative source of supply a lufther schedule of supply charactedstics and eafihirg alrangerrents based upon Section I ofthis Report shou)d be provided.
7
A sumrrary ol the condition of tjre installation in teflns of safety should be clearly stated in Section E. Observations, if a[y, should be categorised i[ Section K using the coding Cl to C3 as appropdate. Any observation given a code C I or C2 classification should result in the overall condition of the ilstallation being reported as unsatisfactoly.
Wherever pmcticable. items classified as 'Danger present'(C1) should be made sale on discovery. Where this is not possible the owncr or user should be given w tlen notification as a matter of urgency.
l0
Where an obseNation requires further investigation (FI) because the inspection has revealed an apparent dclicicncy which could not, owing to the extent or limitations of the inspection, be fully identified and fufther investigatior may reveal a code Cl or C2 item, this should be recorded within Section K, given the codc Fl and nrarked as unsatisfactory in Section E. If tlre space available for observations in Section K is jnsufficient, additional pages should be provided as necessary.
1l
The date by which the next Electrical Iustallation Condition Repofi is recommended should be given in Section F. The i[terval between inspections should take into account the type and usage of the installation and its overall condition.
t2
Any deficiencies with intake equipment should be reported to the person ordering the work.
CONDITION REPORT
GUIDANCE FOR RECIPIENTS (to be appended to the Report) This Report is an important and valuable document which should be retained for future reference' I The purpose of this Repofi is to coninn, so far as reasonably practicable, whethel or not the electrical installation is in a satisfactory condition for continued service (see Section E). The Report should identify any damage, deterioration, delects and/or conditions which may give rise to danger (see Section K).
2
The person or.dering the Report should have received the'original' Repofi and the inspector should have
3
The 'original' Report sbor.rld be retained in a safe place and be made available to any pe$on inspecting or undertaking work on the electrical installatiofl in the future. If the property is vacated, this Report will provide the niw orvner/occtLpier with details of the condition of the electrical installation at the time the
I
retained a duplicate.
Report was issued.
4 5
Where the instatlation incorporates a residual cunent device (RCD) there should be a notice at or near the dcvice statirg that it should be tested six-monthly. For safety reasons it is important that this instruction is followed. Secrion D (Extent and Limitations) should identify fully the extent ofthe installation covered by this Report and any limitations on the inspection afld testing. The inspector should have agreed these aspects with tlte person ordering the Report and with other ilterested parties (licensing authodty, insurance company, mortgage provider and the like) before the inspection was caffied out.
6
Some operatioral limitations such as inability to gain access to pafts of the installation or an item of equiplrent may have been encountercd during the inspection. The inspector should have noted these in Section D.
7
For items classified in Section K as Cl ('Danger present'), the safety of those using the installation is at risk, and it is recommended that a skilled pe$on or persons competent in electrical installation work undeftakes the necessary remedial work immediately.
8 9
l0
For-items classified in Section K as C2 ('Potentially dangerous'), the safety ofthose using the installation may be at risk and it is recommended that a skilled person or persons competent in electrical installation work undeftakes the necessary remedial work as a matter of urgency. Where it has been stated in Section K that an obsen'ation requires fufiher investigation (code Fl) the inspection has reveale{ an appareot deficiency which n.ray result in a code Cl or C2, and could not, due to the extert or limitations of the inspection. be fully identified. Such observations should be investigated rvithout delay. A fufiher examination ofthe installation will be necessary, to determine the nature and extent
ofthe apparent deficiency (see Section F). For safety rcasors, the elect cal irstallation should be re-irspected at apprcpriate intewals by a skilled perso[ ol persons, competent i[ such work . The recommended date by which the next inspection is due is stated in Section F of the Report under 'Recommendations' and on a label at or near to the consumer unit/ distribution board.
CONDITION REPORT INSPECTION SGHEDULE
GUIDANCE FOR THE INSPECTOR
I 2 3 4
Section 1.0. Where inadequacies in the intake equipment are encountered the inspector should advise the person ordering the work to inform the appropdate authority. Older jnstallations designed prior to BS 7671:2018 may not have been provided with RCDs lor additional protection. The absence of such protection shorild as a minimum be given a code C3 classification (item The schedule is rtot exllaLrstive. Numbers in brackets arc regulatjo[ references to specifled requirements
I
EXAMPLES OF ITEMS REQUIRING INSPECTION FOR AN ELECTRICAL INSTALLATION CONDITION REPORT A visual inspection should first be made ofthe exterual cordition olall electrical ecluipn.rent which is not concealed.
Futher delailed inspcction. inch"rcling patial dismantlil1g ofequipmert with the person oldcri[g the lvor-k. (651.2)
as
required. should be caried out as agreed
These examples are not exhaustive. Numbers in brackets are Regulation ref'ercnces.
EXTERNAL CONDITION OF INTAKE EQUIPMENT (VISUAL INSPECTION ONLY)
. . . . . .
Service cable
Sclvice heacl Earthing auatgerlents Meter tails
Meterirg equipment Isolator (where present)
Where inadequacies in intake equipment are encountered. it is recommended that the pemon orde ng the fepoft infolms the appropliate authority.
PRESENCE OF ADEQUATE ARRANGEMENTS FOR PARALLEL OR SWITCHED ALTERNATIVE SOURCES
. .
Adequate affangen.]el'lts where a generating set opelates as a switched altemative to the public supply (551.6) Adequate arangenents where a generating set operates in parallel rvith the public supply (551.7)
AUTOMATIC DISCONNECTION OF SUPPLY
.
Main earthinglbonding arrangements (411.3: Chap 54)
I
Prcscncc ol distributor's carlhing arrangcmcnt (542. I .2. l: 512.1.2.2), or
presencc of installation cafth clectrodc arrangcnent (542.I .2.3)
2 3 4 5 6 7 8 .
Adequacy of earthing conductor size (542.3: 5,13. L I ) AdeqrLacy ofearthir'rg conductorconnections (542.1.2)
Accessibility of eafihing conductol'connections (543.3.2) Adcquacy of maiu plotective bonding conductor sizes (544.l) Adequacy and location of main protective bonding conductor connections
(
543.3.2; 544.1.2)
Accessibility ofall protective bonding connections (543.3.2)
Ptovisior of
earth
ing/bonding labels at all app;opriate locations (514.13)
FELV - recluiren.rcDts satisfied (41 1.7; 4l 1.7.1)
OTHER METHODS OF PROTECTION
(Where any of the methods listed below are employed details should be provided on separate sheets)
. . . . .
Non-condr.rcting location (,118.1)
Earth-fiee local equipotential bonding (418.2) Electrical separatior (Section 413;418.3) Double insulation (Section 412) Reinforced insulation (Section 412)
DISTRIBUTION EQUIPMENT
. . . . .
r.
Acleqr"racy o1'
Security
working spacctacccssibility to equipnlent
ofllxirg
(
1
(134.1.1)
Condition of insulation of lir c pans (,116.
I)
Aclequacl, seculitv ofbariers (-116.1)
Condition ofcnclosure(s) in terrrs of lP rating etc (416.2)
32. l
2;
5 1 3.
1
)
Condition of enclosure(s) in terms offire rating etc (421.1.6; 421.1.201' 526.5) Enclosure not damagedtdeteriorated so as to impail safety (65 1.2)
I
Presence and effectiveness of obstacles (417.2) Presence of main switch(es), linked where lequired (462.1; 462.1.201, 462.2)
I
Operation of main switch(es) (functional check) (643.l0)
I
Manual operation of circuit-breakers and RCDs to prove discorrection (643.10)
I
Confirmation that integral test buttol/switch causes RCD(S) to ldp when operated (functional check) (643.l0) RCD(s) provided for thult protection
-
includes RCBOs (41 1 .4.204;411.5.2; 531.2)
I
RCD(s) provided for additional protection/requireurents, where required includes RCBOs (411.3.3;415.1)
I
Presence of RCD six-monthly test notice at or near equipment, where required (514.12.2)
I
Presence ofdiagrams, charts
ol schedules at or near equipment, where required (514.9.1)
Presence ofnon-standard (mixed) cable colour waming notice at or near equipment, where required (514.14)
. . . .
Presence of altemative supply waming
lotice
at or near equipment, where required (514.15)
Plesence ofnext inspection recommendation label (514.12.1) Presence of other lequiled labelling (please specify) (Section 514)
of prctective devices, bases and other components; corect type and rating (no unacceptable thermal damage. arcing or overheating) (411.3.2; 411.4; 411.5; 411.6;
Compatibility
signs
of
I I
Sections 432, 433)
. . .
Single-pole srvitching or protective devices in line conductors only (132.14.1;530.3.3)
I
Protection against mechanical damage where cables enter equipment (522.8.1;522.8.5; 522.8.11)
I
Protection against electromagnetic effects where cables e[ter fefiomagnetic enclosures (521.5.1)
DISTRIBUTION CIRCUITS
. . . . . . .
Identification of conductors (514.3.1) Cables correctly supported throughout lheir mn (521.10.202; 522.8.5)
Condition of insulation of live pafis (416.1) Non-sheathed cables protected by enclosure in conduit, ducting or trunking (521.10.1)
Suitability of cortainment systens for continued use (including flexible conduit) (Section 522) Cables correctly tenninated in enclosures (Section 526)
Confirmation that ALL colductor connections, including connections to busbars, are corectly located in temlinals and are tight and secure (526.1) Examination ofcables for signs of unacceptable themal or mechanical damage/deterioration (421.1; 522.6) Adequacy ofcables for currenlcarrying capacity with regard for the type and nature ofinstallation (Section 523)
Adequacy ofprotective devices: type and ruted cunent for fault protection (411.3) Presence and adequacy of circuit protective conductors (411.3.1.1; 543.1)
Coordination between conducton and overload protective devices (433.1; 533.2.1) Cable installation methods/practices with regard to the type and nature ofinstallation and extemal influences (Section 522) Where exposed to direct sunlight, cable
ofa suitable tlpe (522.11.1)
Cables concealed under floors, above ceilings, in walls/partitions less than 50 mm from a surface, and in partitions containing metal pafts
1 2
installed in prescribed zones (see Section D. Enlent and limitations) (522.6.202) or incorporating earthed aflnour or sheath, or run within earthed wiring system, or otherwise protected against mechanical damage by nails, screws and the like (see Section D. Extent and limitqtions) (522.6.204)
Provision offire barriers, sealing arrangernents and protection against thermal effects (Section 527) Band
II cables segregated/separated from Band I cables (528.1)
Cables segregated/separated from non-electrical seryices (528.3)
Condition of circuit accessories (65 1.2)
Suitability ofcircuit accesso
478
es
for extemal influences (512.2)
. . . . .
Single-pole s$.itching or protective devices in linc conductors onl1 ( I32.1.1.1: 530.3.3)
of connections. including cpcs, within accessories and to fixed and stationary equipment identifyilecord nulbers and locations of items inspected (Section 526)
Adequacy
Presence, operation and corect location of appropriate devices Section 537)
-
fol isolation and switching (Chapter 46;
General condition of wiring systems (651.2)
TenpeBture rating of cable insulation (522.l. t; Table 52.1)
FINAL CIRCUITS
. . . . . .
Identification of conductors (5 14.3.
l)
Cables conectly suppoted tluoughout their run (521.10.202:522.8.5)
Condition of insulation of live pats (416.I ) Non-sheathed cables protected by enclosure in conduit, ducting or trunking (521 . 10.1) Suitability ofcontainment systens tbr contirued use (including flexible conduit) (Section 522) Adequacy of cables for cuuent-carrying capacity with regard for the type and nature of installation (Section 523 )
. Adecluacy ofprotective devices: type and rated cuffent for fault protection (411.3) . Ptesence and adequacy of circuit protective corductors (41 1.3.1.1: 543.1) . Co-oldination between condLrctors and ovelload protective devices (433.1;533.2.1) . Wi ng system(s) appropriate for the type and nature of the installation and external influences (Section 522) . Cables concealed under floors, above ceilings, in walls/partitions, adequately protected against damage r
5
22.6.20 I ; 522.6 )02:. 522.6.203; 522.6.204)
1 2 .
*lbr all socket-outlets ofmting 32 A or iess unless exempt (411.3.3) *for the supply of mobi)e equipment not exceeding 32 A mting for use outdoors (4 I I .3.3) *1ir cablcs concealed in walls at a depth of less than 50 mn (522.6.202, 522.6.203) *fbr cables concealed in walls/partitions containing metal pafis regardless ofdepth (522.6.203) *for'final circuits suppll,ing lurrinaires within domestic (household) prernises (411.3.4)
Provision offire barjers, sealing arrargemerts and protection against themal effects (Section 527) Band II cables segregated/separated from Band t cables (528.1) Cables segregated/separated from non-electrical services (528.3)
TenninatioD ol cables at enclosures identify/record numbers and locatiots of jterns inspected (Section 526\
1 2 3 4 . . .
illcol'poratitg eafthed an'nour or sheath, or run within ealthed wiring system, or otherwise prolected against mechalical damagc by nails, scrervs and the like (see Section D. Extent and lintitations) \ 522.6.20 I ; 522.6.20 4\
Plovision ofadditional protection by 30 rnA RCD
I 2 3 ,1 5 . . . .
installed in prescribed zones (see Section D. Exlent (.tnd limitdtiotls) (522.6.202)
Connections under no undue strain (526.6)
No basic insulation ofa corductor visible outside enclosure (526.8) Connections
oflive conductors adequately enclosed (526.5)
Adequately connected at point of entry to enclosure (glands, bushes etc.) (522.8.5)
Condjtion ofaccessories including socket-outlets, switches andjoint boxes (651.2)
I
SuitaLrility ofaccesso es tbr cxtemal influences (512.2)
Single-pole srvitching or protective devices in line conductors only ( 132.14.1, 530.3.3)
*Note: Older installations designed prior to BS 7671:2018 may not have been plovided with RCDs for additional protection.
I
ISOLATION AND SWITCHING . lsolators (Sections 460;537)
1 2 3 4 5 6 .
-
state
if tocal or remote from equipment in question (Section 462; 537.2.7)
Capable ofbeing secured in the OFF position (462.3)
Corect operation verified (643.10) Clearly identified by position atd/or durable marking (537.2.6) Waming label posted (514.11.1;537.1.2)
ir
situations where live parts cannot be isolated by the operation ofa single device
Presence and condition ofappropliate devices (464.1; 537.3 2)
Acceptable
location
state
if
local or remote fi'om equipment in questio[ (531 .3.2 4)
Capable olbeing secured iu the OFF position (462.3)
Conect opemtion verified (643.10) Clearly identified by position and/or durable marking (537.3.2.4))
Emergency switching/stopping (Section 465: 537.3.3)
1 2 3 4 .
Acceptable location
Switching offfor mechanical maintenance (Section 464; 537.3.2)
I 2 3 4 5 .
Presence and condition ofappropriate devices (Section 4621537.2.7)
Presence and condition ofappropriate devices (Section 465;,537.3.3; 53'7.4)
Readily accessible for operation where danger might occur (537.3.3.6) Correct operation verified (643.10) Clearly identified by position and/or durable marking (531 .3.3.6)
Functional switching (Section 463; 537.3.1)
I 2
Presence and conditiou of appropriate devices (53 7.3. l.
Coffect opemtion verified (537.3.
1. I
l;
537 .3 .1
.2)
; 53'7.3.1.2)
CURRENT-USING EQUIPMENT (PERMANENTLY CONNECTED) . Condition of equipment in tenns of IP raling etc (416.2) . Equipraent does rot constitute a fire hazard (Sectiol 421 )
. . . .
Enclosure not damaged/dcteriorated so as to impair safety (134.1.1; 416.2; 512.2)
.
Recessed luminaires (downlighters)
Suitability for the envirorment and extemal influences (512.2) Security
offixing ( 134.1.1)
Cable entry holes in ceiling above luminaires, sized or sealed so as to rest ct the spread offire: List number and location ofluminaires inspected (sepamte page) (527.2)
I 2
Corect type of lamps fitted (559.3.1)
3 4
No signs oloverlteating to surrounding building fabric (559.4.1)
lnstalled to minimise build-up of heat by use of "fire rated" fittings, insulation displacement box or similar (421.1.2)
No signs ofovedreating to conductors/temrinations (526.1)
PART 7 SPECIAL INSTALLATIONS OR LOCATIONS
.
If alry special installations or locations
are present, list the particular inspections applied.
r"'-'\ ; f; r-renenv
CONDITION REPORT INSPECTION SCHEDULE FOR DOMESTIC AND SIMILAR PREMISES WITH UP TO 1OO A SUPPLY NOTE: This /ornt is suituble for nnn_t tpes oJ sntaller itlstallLnidl. nat e\Lltl'hel|
tl
ot Ta()\tFs Cl
or C2
Llonlestic-
LI\I
C3
OIJTCO}'IE
tTE\l
\()
tL'\e L.des dbore. P'b\il? addiiordl .orr .rt {here apphr,'ide C1. C2 C} dnd FI.oded trcnts D be r?.orcled n] Sectot K o/ the Condniah Repotl)
DESCITIP-IIO\
IXTDR\AI- CO\DITIO\ OF I\T.\KE EQLIP]IE\T (\:lSUAT- I]SPECTIO\ O)L\
t.0
)
tl ll Eartbirg arrang.Drcnt
t.3
l..t l.-i
l$lxlor (shc1r
preseDr)
20
PRESE\CE OFADEQUATE ARR{:{GE]IE\TS FOROTHER SOURCIS SUCH AS IUICROCtINf ILdTORS (551.61 551.7)
1.0
EARTIIING
I l i.: t.l
Prcsencc and conditiof
ofdistribulori eaihing amngemeni (542.1.:.li
PreseDce drd conditiotr
olcanh clccrrodc con,rccrion \hcrt apllicable (j:12.1.2.1)
l.t
Conianation
ofe lliirs
1.5
Ac.essibiliil
and condllion
l.(i
Corli
ll
ConditioD ind !cccssibiliry oinraln protectl\e bonding conducror connections (543.1.2i 5:14.1.2)
/
BONDI\G ARRAIGENIENTS (:lIl.3i Chap
54)
Pro\isidr ol c.nf fg Lrondlrg lahcls nl rLlrtp,op,inle lo.rLilnN (51-l
narion olmain
5,12 1.2.1)
ll
1)
conductor rizc (5.11.1:511.1.I )
olelnhlng conduclor
frol.(i\c
ar MET (5,1i
bondirg co.ductor
'izcs
(5,1.1
:.1)
I)
Acccssibiliti xrd conditioD ofotil.r prorcctn c bondnlg cornccriors
(5ll
3.1:
5:ll.l :)
CONSU]ITf,R UNIT(S) / DISTRIBLiTION BOARD(S)
.1.0
.11
Adcquac! ol $orknrs spacc,accc$ibi1iry to cofsnincr nnitidistribrtion board ( 132.12: 513.1)
l.l
SccuritY oIfixms
(
131.1.1)
Condirol olerclosnre(s) in tems oflP ntiDg etc (.116 2) (i,rdirion ol ercl{xr,e(i)
+.{
Lllr.l6urc nol
renD! o1_nr kring erc (.111.l.l0li 516.5)
danragcd dctcriomtcd so as to imfairsal_e!
ofnaii
Prescncc
i11
' 'remr! o r..' , {".!
l!funuiloperalioi
(6j
l.l)
I
linkcd s$itch (as rcqnncd by.16l.l.20l)
.
ol.i
'r.'.IuiJl.t.r(
,o,.t.
I
0,
I
rn-bredkea and RCD\ to pro\e disconDedion
(6:ll.l0)
I
Coa'e.r dcrtilicirion ol circnit details ard protectile de\ ices (5l:l 8.1: 51.1.9.11
r
t0
.t.l
t
oiRCl) si\inonlhly
Prcscnce
resr notice aI or near consnmer
nnit/dislribuliN
bo. (5l:l.l1.2) u.il/dutribution
PreseDce oInoD-stllnd:rrd hnixcd) cablc colourwaarhq riolice at ornear consumer
.{.ll
Presence
1.ri
Prcscncc olorher rcqnired labellin{ (r,lexse spe.ifv) (Secrion 51,+)
ofllternative $rpp\ \,xlrlhg noticc
at or
nc
consuncr unil,dinribuion board (514 15)
Conrpatibility offrotectire delices. bases and other cornponcnts: concct ofunNcceptable lliellllal dxnugc. arclfg or o\$hcating) ( ,111.3.2::lll.:li
tpc and rating (No si-qns :lll.ir.ll1.6r SectioDs 4ll.
.11-l )
Sinslerole sitchin-q or proleclive dericcs nl
I t(
Prolection agrilrsl mechdnical daDig. $ hcrc clblcs .n tcr cof nnner unit'd istr ibur ion boald
(l::.1,1 l:52:.3.1r51:.3.5: 5l:.8
Lnre
cordlcror oDly (131.11.1: 530.3
I
ll)
:l l7
Protection agai$t clectronlagneli. eftecN shere.it,les eDter consuDrcr unit/diStrlbulion board/
l.ls
RCD(s)
proideil
ior fault
frot..t(n ' nltluJes
RCiIO\ {.ll1..1204;411 5.2i 531.2)
RCD(S) pro',ded f{)r ad.trtional prote.tio!/requiremeDts - nrludes RC IIOS (4 l l
415.1
)
a.nlirn,ti.n ofind!.ation
l.l1
CoDlirnlation thar-{Ll conductor coD ne.tions. in.luding .oDnections tobusbais, are.otre.th located in terminah and dre tishrand secure (il6.l)
+12
Adequate
atingen.nrs
that SPD n iun.non.l
l6:l
.l l:
.t.20
-+l
s,here a generatiog set operates!sa switched alternative !o rhe publi. supplr
(jsr.6)
ll
I I
i)
.1.15
.l
I
Adequate arangements where a gen.rating !.r of'rnret in parallel with the
llblic
supplr i j i I
-
OUTCO}IE luse.alles dbav. Ptotnlc Lnl.litu, .or" qtt $hth appto?tntk ( l (:, cJ o LlFI.otlel ite 6 to be k.atLl\; S.dk t KaJ lP Gn\lition Rcpnl 5.0
FI\,{L CIRCUITS
I
-il
lddn'ti.rtron of.ondu.o ! (5l+
5.2
(?bLe! comctl) suploned rlmu-qhout fteir rur (521.10.202: 521.8.5)
il
Condition
5l
Non slrcathcd c.blcs prorect.d by e..losure nr.ondun. ducrirlg or rLlrnkirs (511.10.1)
ofii\rldrio,iol li!eta
L)
s (-116.1)
'i'o irlcLude the inlegrity ofcondurr and truflkirg sysrcDs (mctallic and plastic)
55
Adeqnaly ofcables for .ufl'cnl'car) irlg c.paclty t!ith.egad for the rype and natun ofiNtallation (Scction
5li)
(i)ordinarion be$leen conducrors arld ovcrload protectire delices (:ll3.i: 5j3.1.1) Adcquacy ol
protc.li\. dc!i.es:
lypc and rated curent litr innll prolcclio. (41 1.3)
of.!!uir
53
Prcscncc.Dd adcqudc)
59
Widng sysleDr(, rppropriale tor rhe ry])e and nalLtrc oithe irstallation and extemal influences (Seclion 522)
i
ton.ealed.ablei lrslrlied in prescrib!'d zorcs
t0
5ll
(
ables conceal.d
d d Iit itotia t\
5ll
und{ flooN.
prcleclive .odnciors
dbo\
lor
$ckcl
outlcrs ol rxlnrg
li,r eabies conccalcd nr
Ll
5 l1
l2
by RCD not cxcc.diDg
(see Section D.
tri.,r/
l0 nA:
A or less. urless an exccp(ion is pcxnittcd Dot cxcccdirg
\all\ pallliors .on(iining
l2 A
(lll.i il I l)
rNring ibr use onrdoos (.111
50
(511.6.201:
ill.6.20l)
Dieul prrs resrrdles ofdepth ( 52:.6.103)
circurts nrpplr,n- lrmn[jres wiftnr donlenic (houschold) prcDriscs (411.i.1)
Pro\isio! ofJire ba'r1e$. seahlq amrgcnrcn6
l ,rl il
cxLrLc\
aod prolcctioD ag!insl thenDal efie.ts (Scctiofl 527)
\cgrecdLed icpnrllcd liom U.Dd I .rbles (518 1)
( rb .s scgr.g .d ..f.fur.d
(nnniu,,icrllon\ crh
Llorn
aiLjlcs regr.gat.d scpararc,l liofr fon
5ll
itutb,s)(52].6.102)
e.eituSs or !r N.llslranilions- adcquately prolecled !-sainst damige
1orcablei corcerleLlin $!l1i drr deplh ofless than
i
[. c tonJlr
(522-6-204)
thi !,|ply olnrcbile equiunenl
.Inrdl
1.3.1i Scction 513)
(s('e SecriorD-
Punnrn oladdirlonalrcquiLclncrrs lor frorectior . lor a I
(41
iDg
l5l8
l)
clccui.ali.h cc\ rilS l)
remination of.rbles rt e.closulrs - indic|tc c\tcnt ofsamplir-q in Scction D ol thc
r.pol,1 (Se.t1otr
j16)
.Connecrions soudly nradc ind under no undue stanr (526.6)
. No b.sic insularnm ol r (indurlur . Cnnrecli!tr)s .
5.13
\ isibLe oul\ide enclosui.
l5l6
E)
olli\c $xlLLno\ rdcqxrr.l) .r.llr{'d (i:6 i)
Adequrtely conne.red ar poinr ofcnx'! lo cnclosluc (gltuxls. bushes etc.) (521.8.5)
Condilion ol acccs$rics iDcludiDg socket-outlels. surehcs xnd loinl box.s (651.2h.)) Strnabillt) ola..essoher li)r crre,ml nnnence! Adequrcl of\vorkifg space'acccsibility
i.ll
Sirgle-pole slnchilg or proreclire devic.s in
LOCdIIO\(S) CONT.\I)I\C
jl l.l)
cquipDenl (112.lli
510
1o
(
Linc
A tsATH OR
jl l.l
)
condrclob only ( 131.1,1.1, 510 1.3)
SHO\\ER
Additional protcclion lbr nlllo$ \oltage tLV) circnits by RCD not cxcccdnig
l0
(701.:lll.l.l)
Where uscd as a prorcelivc Deasure. reqnirenrenN lor SELV or PELV met (701.414.:l 5) Shaver sockcrs
Prescn.e
ionrtry $irh BS !^_ 61558-l-5 lonne.lr- BS l515 (701.512
ofqlleDrcntary
Los \oLtage (e.g
l)
bond rg condu.roN. untess not reqnired by BS 7671:2018 (701..115.2)
Iio roh) sockct
outlcts silcd al lcasr r Dr
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nu
2one I (701.51 2
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\ame (Capila l\)
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ilan).
(Record separately the results of pdicular illspeclions applied )
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Date.....
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APPENDIX 7 (tnformative) HARMONIZED CABLE CORE COLOURS 1
Introduction
The requirements of BS 7671 were hatmonized with the technical intent of GENELEC Standanl HD 3g4.5.514: inclLtdiirLg 514.3: ldenti/ication oJ.couthtctors, now withdrawn.
Identificqtion,
Amendment No 2: 2004 (AMD 14905) to BS
j6j
t:2001 implemente
-
BS EN 60445:2000 Basic and sa/bn principles.fbr man-mcrchine inrerface, nctrking .lnd iclentifi..ation of eqLtipment terminals ard of tenninations BS EN 60446:2000 Basic and salbht principles fbr the ntctn-machine intet'face, marking and itlentification. Identification oJ'conductors by c,ctlow.s or ntnteruls.
NorE:
S,bseq.entry. BS EN 60445 and BS EN 604,16 havc becn combined into BS EN 60445:2010.
This appendix provides guidance on marking at the interface between old and hamonized colours and marking and general guidance on the colours to be used fbr.condr.rctors.
In the British Standalds for fixed and flexible cables the colours have been harmonized. BS 7671 has been rnodilied to align with these cables. but also allows other suitable l'nethods of marking connections by colour (tapes, sleeves ot discs), or by alphanumerics (letters and/or numbers). Methods may be mixed withir an installation.
2 2.1
Addition or alteration to an existing installation Single-phase installation
An addition or an alteration made to a single-phase installation need not be marked at the interface provided that:
1 2
the old cables are correctry identified by the corours recl for line ancl brack for neutral, aud the new cables are co.'ectly identified by the corours brown for rine and blue for neutral.
2.2
Two- or three-phase insta ation
Where an addition or an alteration is made to a two- or a three-phase installation wired in the old core colours with cable to the new core colours, unambiguous ideltification is recluired at the intedace. Cores shoulcl be marked as
follows;
Neutal cotductors Old and new conductors: Line condttclors Old and new conductol.s:
TABLE 7A
-
Example of conductor marking at the interface for additions and alterations to an AC installation identified with the old cable colours
Function
Old conductor Colour
New conductor
Red
Marking LI
Marking LI
Colour
Line I ofAC Line 2 ofAC
Yellow
L2
L2
Blackrr)
Line 3 ofAC
Blue
L3
L3
Crcy
Neutral ofAC
Black
N
N
Protective coDductol.
Green-and yellow
rrr Tht ee
484
Lt,L2,L3.
single-core cables with insulation of the same colour tray be used
Brorvnllr
l
tslue
Creen-alld-
if identified
at the telmjnations.
3
Switch wires in a new installation or an addition or alteration to an existing installation
Where a tt'o-core cable with cores coloured brown and blue is used as su,itch wires. both conductoN beins line conductors. the blue conductor should be marked brown or L at its teuninarions.
4
lntermediate and two-way switch wires in a new installation or an addition or alteration to an existing installation
Where a thtee-core cable with cores coloured brown, black and grey is used as srvitch wires, all three conductors being line conductors. thc black and grey conductors should be marked brown or L at thet teflrinations.
5
Line conductors in a new installation or an addition or alteration to an existing
installation Power circuit line conductors should bc coloured as in Table 51. Other line conductors may be brown, black, red, orange" yellow, violet, grey, white, pink or tulquoise. In a two- or thtee-phasc power circLrit the line conductors u'lay all be olone ofthe pemitted colours, either identifled L2, L3 or marked btown, black, grey at their teminations to show the phases.
Ll,
6
Changes to cable core colour identification TABLE 78
-
Cable to BS 6004 or BS 7211 (ftat cabte with bare cpc) New core colours
SingLc-core + bare
Brown or Blue
Trvo core + bare cpc
Bro$n, Blue
Alt. rw-o-core- barc cpc
Brorvl. Broun
Thrce-cole + bare
TABLE 7C
Rcd. Yeilow. Blue
-
Brown, Black,
Standard 600/1000V armoured cable BS 6346, BS 5467 or BS 6724
Cable type
Old core colours
Singlc-core
Red or
Tlvo-core
lted, Black
Brown. Blue
Three-core
Red. Yellou. Blue
Brown, Black. Crey
Four-cole
Red. Yellow. Blue. Black
Brcwn, Black. Grey. Blue
Five-core
Red, Yellorv. Blue. tslack, Green-and-
Blorvn. B1ack, Crey, Blue, Green-and-
veilou,
yellow
TABLE 7D
-
Black
Nerv core colours
Brown ol Blue
Flexible cable to BS EN 50525 series (supersedes BS 6500)
Cable tvpe
Old core colours
I$o-core
Bloun. Blue
No change
Three-core
Btou'n. Blue. Creen-and-vellorv
No change
Four-coLe
Black. Blue. Brorvn, Gr-ccn-and-yellotv
Brown. Black. Grev. Green-and-vellow
Five-core
Black. Blue. Btown. Black. Grcenand-yellou
Brown. Black, Gtey. Blue, Green-and-
New core colours
yellow
Addition or alteration to a DC installation Where an addition or all alteration is made to a DC ilstallation wired in the old core colours with cable to the new core coloLrrs, unarrbiguorLs identification is required at the interface. Cores should be rnarked as follows: Neulra I an d
m i dpoitlt
cotld Ltclors
OId and new conductors:
N{
Litte cotttltrttots OId and new conductols:
Brown or Grey. or
L,L+orL TABLE 7E
-
Example of conductor marking at the interface for additions and alterations to a DC installation identified with the old cable colours Ne\r conductor
Function
Trvo-wire unearthed DC power circuit Positive of two-wire circLril Nepative of two-wire circuit
Two-wire earthed DC power circuit Positive (of ncgatjvc cafi hed) circuit Negative (of negative eafthed) circuit Positive (of positive ealthed) cilcuit (of positivc carthed) circLril
Three-lvire DC Dorter circuit Outer positivc of t$o-$irc cilcuit deli\ed lionl thrcc \\ irc systcnl Outer negative oftrvo-wire circrLit derived from three-wire systenl
Positivc of thrcc-wire cir-cuit
Mid-wire of three-wire cilcuit Necative of threc-rvie circuit
r"*\ fi uenanv 3
APPENDTX 8 (tnformative)
CURRENT.CARRYING CAPACITY AND VOLTAGE DROP FOR BUSBAR TRUNKING AND POWERTRACK SYSTEMS
1
Basis of current-carrying capacity
The curent-carying capacity (I,o) of a busbar trunking or powertack system relates to continuous loading and is declared by the manufacturer based on tests to BS EN 61439-6 (busbar trunking) or BS EN 61534 series of standards (Powertrack). The curentcarrying capacity is designed to provide for sitisfactory life of the sysrem, subject to the thermal effects ofcanJing curent for sustaiued perioils in normal service.
I
Considerations affecting the choice of size ofa busbal tnnking or powertrack system include the requirements for protection against electric shock (see Chapter 4l), protection against thermal effects (see Chapter 42l, overcunent protection (see Chapter 43 and sec 4 below) and voltage drop (see sec 5 below).
2
Rating factors for current-carrying capacity
The curent-carying capacity (I..) can be aflected by the ambient temperature and the mounting conditions (for example the orientation ofthe conducton). Ine for Powertrack according to BS EN 61534 is defined as'The rated cu[ent value assigned to by the manufacturer and to which operation and pefonnance characteristics are referred.,
a
Powefirack svsrem
InA for a busbar trunking system according to BS EN 61439-6 is defined as'The rated curenr value decJared by the manufaaturer which can be carried without the ten'rperature rise of various parts ofthe busbar trunking system exceeding specified limits under specified conditions., InC for a busbar trunking systern according to BS EN 61,+39-6 is the value of the curent that can be carried by a circuit loaded alole, undcmonnal service conditions rvithout the temperature rise of the various parts of the ASSEMBLY excceding the lirnits spccified.
lnstallation ambient temperature For a busbar trunking system, ifthe a[rbient tempemture exceeds 35 'C the rating factor krA to be applied is obtained from the manufacturer ofthe busbar trunking system (k,^ : 1 for 35 "C). The effective curent-carying capacity (I"A) at the new temperature is kr^ x InA.
For a busbar trunki[g system the moullting factor k:c to be applied is obtained from the manufacturer ofthe busbar system.
The effective currenlcarrying capacity ([,,,6) under the new mounting conditions is k26 x 1.6.
In a typical installation, both facto$ may have to be taken into account and the effective current-canying capacity (I'"q) then becomes krc x hc x Inc where:
k,. k,.
is a temperature factor, equal to is a mounting factor, equal to
I
I
at an ambient air tempemture
of35
NOTE:
3
oC
in the reference mounting conditions.
For a powerhack system the effective cunent-canJing capacity maoufacturer in accordance with BS EN 61534 series undcr all normal conditiorrs.
is the rated curent
I,,A declared
by the
Effective current-carrying capacity
I. must be not less than
Ib, such that:
I, >
I
I
Mounting attitude
huking
I
Ih
where:
L
is the effective cunent-carrying capacity olthe busbar trunking (l'.. ) or po\\,ertrack system (1" \) tbr continuous serr,/ice under the paticular installation conditions. and
I
is the design currenr ofrhe crrcuit.
4
Protection against overload current
The minimur operating current ofthe protective device should l]ot exceed 1.45 I,. Where the protective der ice is a fuse to BS 88 series or a circuit-breaker to either BS EN 6094?-2 or BS EN 60898, this requirement is satisfied by selecting a value of[. not Less tl]an 1,,, where I,, is the mted curent or current setting ofthe device protecting the circuit against overcurrent.
5
Voltage drop
The voltage drop (V) for the busbar trunking or powefirack system is obtained from the manufacturer It is usually expressed as mv/ampere/metre, tabulated according to the value of the load-circuit power factor. The voltage drop given is calculated orr the basis ol a single load at the end of the run and, in this case, the total voltage drop : V6 x lr x L / 1000 volts, where L is the length olrun in mctres.
lu the case of an evenly distributed load (tapped off at intervals along the busbar trunkirg or powertrack system) then the voltage drop at the furthest tap-offpoint may be taken as 0.5 V6, and is calculated by the above method.
In the case ofan unevenly distributed load it will be necessaly to calculate the voltage dlop for each section between tap-offpoints and add them together to flnd the voltage drop at the fufihest tap-offpoint.
488
APPENDIX 9 (lnformative) DEFINITIONS
- MULTIPLE
SOURCE, DC AND OTHER SYSTEMS
Fig 9 - Explanation of symbols used within Appendix 9
,
T
Neutral conductor (N)t m dpoint conductor (M)
7
Protective conductor (PE)
r
7
7
Cornbined protective and neutral conductor (PEN)
NOTE 1: The dotted lioes iDdicate the pa s ofthc systen that ale not covered by the scope ofthe Standald. whereas the solid lines indicatc the pall that is covercd by the Standard NOTE 2: Forp vate systeins. the source and/or the distribution system maybe considered meaning
Fig 9A
-
oftlris Standard. For this
as
pafi of tl'te installation within the
case. the figures may be completely shorvn in solid lines.
TN-C-S multiple source system with separate protective conductor and neutral
conductor to current.using equipment
.,ffr .' ,oir.
,' ,o-m
j I
i-
so*."
or enerqy 2
a
I
L1
Source of
rf J Y A \-<'
'rru'.'
lva-'" | -----* .(
L2
..
L3 N
a)-)r '-
\
489
-4= I
Fig 98
-
TN multiple source system with protective conductor and no neutral conductor throughout the system for 2- or 3-phase load
L1
L2 L3
")
-+ rYr,,-t,' ,'
N
PE
I
t", I I
b)
I
I Exposed'conductive-parts
-
Equipment n nstalation
NOTES to Figures gA and gB
(l) (2) (3) (4)
No dircct cor[cction tiom cither tlle transtbmrer ncutml point or thc gencrator star point to Earth is permittccl. The interco.nection c.,rductol' bctween either tlre neutral poirlls olthe transtbnners or the generator srar. points is to be insulated. 'l-hc lunction of this concluctol is sirnilar to a pEN: horv.u".. ir,r*rinoit. .o,rn..,"a ro crrr.rertr-using equil,rncnr.
only one conncctioll belween the intcrcoDlected neutra] points ofthc
This connectioD is to be localed inside thc nraiu switchgear asscmbly. Additional earrhing ofthc pE in the installation may be provided.
(fcrR'br,r\ r,r**r 'd
,f=
,oo
490
T
sources anci the pE is to be pr.or,,idccl.
-
Fig 9C
lT system with
Source
l#r(---}r<
lla
ex c cs
ec'co n ductive-parts earthed in groJss
'
cr
ndividually
lnstallalion >
rrrr --
rrrr
I
f-----o
oN')
I I
lmpedance
,r l
'
I
ti
t-
J-
in instaliation
-.....\--.--,/
Source earth
\
Eadh
electrode-/
NOTES Additional earthing ofthe PE in the installation may be provided.
1) (2) (
The system may be connected to Eafih via a sufRciently high impedance. The neutral conductor may or may not be distributed.
Fig 9D
-
L- separated from the protective conductor throughout the installation
TN-S DC system with earthed line conductor
#
lnstallation
L+ PEL
L-
Opuonal application of a battery
Earthing of system
in installation
491
Fig 9E
-
TN-S DC system with earthed midpoint conductor M separated from the
protective conductor throughout the installation
Souace
#
PEM
--t
]
i
?1--i---:
Optional application of a battery
Equipment in installation Earthing of system
NOTE to Figures 9D and 9E Additional earthing ofthe PE in the installation may be provided.
Fig 9F
-
TN-C DC system with earthed line conductor L- and protective conductor combined in one single conductor PEL throughout the installation
I
Z upflonal application of
battery
L+
-r--i----
(PEL) Combined protective and
Ine conductor
a i i --r-i
Exposed-conductive-parts in installation Earthing of system
492
Fig 9G
-
TN-C DC system with earthed midpoint conductor M and protective conductor combined in one single conductor PEM throughout the installation
aour""
!<
>t<
lnstallation
> L+
(PEM) Combined protective and midpoint conductor
Optlonal application of a battery
,--_-t __.1__
in nstallation Earth ng of system
NOTE to Figures 9F and 9G Additional earthing ofthe PEL or PEM in the installation may be provided.
Fig 9H
TN-C-S DC system with earthed line conductor L - and protective conductor combined in one single conductor PEL in a part of the installation
-
A I
--{---
L+
,--i--
(PE) Protective conductor
I I
Optional applicauon of a battery
I
I
!
I
!
I
I
I I
! I
I
I I
I
Earthing of system
! I
I
!
I
I
I
TN-C system
i
TN-S system
i
493
Fig 9l
-
TN-C-S DC system with earthed midpoint conductor M and protective conductor combined in one single conductor PEM in a part ofthe installation
I
Optional applicalion of a battery
I ! I I
Earthing of syslem
TN-C-S DC system I
NOTES to Figures 9H and 9l Additional earthilg ofthe PE in the installation may be provided. Regulation 8(4) ofthe Electricity Saf'ety, Qualjty and Continuity Regulations (ESQCR) states that a consumer shall not combine the neutral and prctective functions in a single conductor in his consumer's installation.
Fig 9J
-
TT DC system
source
lnstallattor I
i
L+
-+-1-
L-
(PE) Protective conductor
application of a betlerv
i
I
Equipment in installat on
-:\ Earthlng of system
494
Earthlng of exposed-
conduclive-pafts
Fig 9K
Source
;
--1
-
TT DC system
lnstallation
ir--1--i
---+----t(PE) Protective conductor
application
f ---.,
of a battery - -.1_
_
ri
):
Earthing of system
{\ =\ Earthing
grpo""o-"onou"tiu"-purt" Equipment in installation
of exposed-
conductive-pa(s
NOTE to Figures 9J and 9K Additional earthing ofthe PE in the installation may be provided.
Fig 9L
-
lT DG system with earthed line conductor L- and protective conductor
-t-
- - - -
-i-{-I
t\
Protective conductor
I l1)
\'
iL-)
----Ji Exposed-conductive-parts
I
Equipment in installation eartrr]ng of system
--\-
Earthing of exposedconductive-parts
495
Fig 9M
-
lT DC system with earthed midpoint conductor M and protective conductor
lnstallation
i PEM -,- - a
Protective conductor
it it
+
Earthing
of system
:
Equipment in installation
Earthing of exposedconductive parts
NOTES to Figures 9L and 9M Additional eafihing olthe PE
(l)
iD the
installation tnay be plovided.
The system lnay be conncctcd to Earth via a stlt'1]ciently high inpeclance
APPENDIX 1 0 (lnformative) PROTECTION OF GONDUCTORS IN PARALLELAGAINST OVERCURRENT ,I
INTRODUCTION
Overcurrent protection provided for conductors connected inparallel shouldprovide adequate protection forall ofthe pamllel conductors. For two conducto$ ofthe same cross-seitional area, conductor matlrial, length and disposition aranged to carry substantially equal currents the requirements for overcurrent protection are stiaightforward. For more complex conductor arrangements, detailed consideration should be given to unequal current siraring between conductors and multiple fault cu[ent paths. This appendix gives guidance on the necessary considerations.
NOTE:
2
A more detailed method for calculating the curent between parallel conductors is given in BS 7769 (BS IEC 60287).
OVERLOAD PROTECTION OF CONDUCTORS IN PARALLEL
When an overload occurs in a circuit containing parallel conductors ofmulticore cables, the curent in each conductor willincrease by the same propofiion. Provided that the curent is shared equally between the parallet .orJu.torr. u single protective device can be used to protect all the conductorc. The cunent-carrying capacity 1Iz) olthe parallel conductors is the sum of the current-caIrying capacity of each conductor, with the-apfropiiate-grouping and other
factors applied.
The current sharing between parallel_cables is a function ofthe impedance ofthe cables. For large single-core cables the reactive component of the impedance is greater than the resistive component and will have a significant effect on the curent sha ng. The reactive component is influenced by the relative physical position ofeacil caute. lq tor example, a circuit consists of two large cables per phase, having the same lengih, construction and cross-sectional area and arranged in parallel with unfavourable relative position (i.e. cables ofthe same phase bunched together) the current sharing may be more like 70130 rather than 50/50. Where the difference in impedance between parallel conductors causes unequal current sharing, for example greater
than l0 % difference, the design cun ent and requirements for overload piotection for each"conductor should be considered individually.
The design current for each conductor can be calculated from the total load and the impedance ofeach conductor
For a total ofm conductors in parallel, the design current Ibk for conductor k is given by:
.I" "^ where:
(i 2, '+
Ib
is the current for which the circuit is designed
Ioo
is rhe design current lor conductor k
zk
is the impedance
?
,+. ,+)
ofconductor k
21, 22 and.2* are the impedances ofconductors 1, 2 and m respectively.
For parallel conductors up to atrd including 120 mm: cross-sectional area (csa) the design current Ibk for conductor k is given by: sk tbk
.L
- rbS;fSFl:l+S;
497
where: S,, ... S- is the csa ofthe conductors and
51
is the csa of conductor k.
In the case of single-core cables, the impedance is a function of the relative positions olthe cables as well as the design ofthe cable, for example, armoured or unarmoured. Methods for calculating the impedance are given in BS 7769 (BS IEC 60287). It is recommended that curent sharing between parallel cables is verified by measurement. The design cunent
[tt
replaces Ib in Regulation 433.1 .1 as follows:
Ibk
(i)
the continuous cuffent-carying capacity of each conductor, Izk,
for each conductor (see Figure
l0A),
if
an oyerload protective device is provided
hence:
T,-,,
(ii)
the sum of the current-carying capacities of all the conductors, ,Izk, is provided for the conducton in parallel (see Figure 10B), hence:
if
a single overload protective device
IbI,k where
I".
is the rated curent ofthe protective device for conductor k
t,t I.
is the continuous aurrent-carrying capacity ofconductor k
!I't
is the sum
NOTE:
is the rated cu-rent ofthe protective device
ofthe continuous curent-carrying capacities ofthe m conductors in parallel.
For busbar systems, infomation should be obtained either from the manufacturer or from BS EN 61439-6.
For powertrack systems, inlotmation should be obtained either from the manulacturcr or from BS EN 61534.
Fig 10A
an overload protective device is provided for each of the m conductors in parallel
- Circuit in which
Supply end
*
,.:j ,,a$
,l
498
Fig - 10B
-
Circuit in which a single overload protective device is provided for the m conductors in Parallel SuPPIY end I,,
Io,
>
1
I"l
l"
l,2
In,,
I
)
I.(
I,; m
k
3
< I" <
Il,u
.l
'l,k
+1..+ .... +
SHORT.CIRCUIT PROTECTION OF CONDUCTORS IN PARALLEL within the parallel section should be where conductors are cornected rn parallel, the possibility of a short-circuit considered.
protective device may not be effective. then If two conductors arc connected in parallel and the operation ofa single each conductor should have individual protection'
curent paths can occur and it ma1 where tkee or more conductors are connected in paraltel then multiple fault load ends of each parallel conductor. This b" ,l"cerra,1 to provide short_circuit protection at ioth the supply and situation is illusttated in Figures 10C and l0D'
Fig 10C
rr1l1
,*
-
Gurrent flow at the beginning of the fault
Fig 10D
-
Current flow after operation of the protective device cs
Figure l0C shows that, if a fault occurs in parallel conductor c at point x, the fault curent will flow in conductors 1, 2 and 3. The magnitude ofthe fault current and the propofiion ofthe fault curent which flows through protecti\e devices cs and ct will depend on the location of the fault. In this example it has been assumed that the highest proportion ofthe fault curent willflow through protective device cs. Figure 10D shows that, once cs has operated, iurrent will still flow to the fault at x via conductors I and 2. Because conductors 1 and 2 arc in paallel, the current through protective devices as and bs may not be sufficient lor them to operate in the required time. lf this is the case, the protective device cl is necessary lt should be noted that the current flowing through ct will be less than the curent which caused cs to operate. Ifthe fault was close enough to cl then cl would operate fiIst. The same situation would exist ifa fault occurred in conducto$ 1 or 2, hence the protective devices al and bl will be required. The method ofproviding protective devices at both ends has two disadvantages. Firstly, ifa fault at x is cleared by the operation of cs and cl then the circuit will continue to operate with the load being caried by conductors 1 and 2. Flence the fault and subsequent overloading of I and 2 may not be detected. Secondly, the fault at x may bum opencircuit at the ct side leaving one side ofthe fault live and undetected. at both ends would be to provide linked protective devices at the supply end (Figure l0E). This would prevent the continued operation ofthe circuit under fault conditions.
An altemative method to providing protective devices
Fig 1OE - Linked protective devices installed at the supply end ofthe parallel conductors
r"*\; f;
r-lemnv
APPENDIX 11: NOT USED APPENDIX 12:NOT USED
t
AppENDIX 13 (tnformative) METHODS FOR MEASURING THE INSULATION RESISTANCE / IMPEDENCE OF FLOORS AND WALLS TO EARTH OR TO THE PROTECTIVE CONDUCTOR SYSTEM GENERAL Measurement of impedance or rcsistance of insulating floors and walls should be carried out with the system voltage to Earth and nominal frequency, or with a lower voltage of the same rominal frequency combined with a measurement ofinsulation resistance. This may be done, for example, in accordance with the foliowing methods of measurement:
1
AC system
-
by measurement with the nominal AC voltage, or by measurement with lower AC voltages (minimum 25 V) and, additionally, by an insulation resistance test using a minimum test voltage of500 V DC for nominal system voltages not exceeding 500 V and a minimum test voltage of 1000 V DC for nominal sysrem voltages above 500 V The following optional voltage sources may be used: (a) The earthed system voltage (voltage to Eaflh) that exists at the measurjng point (b) The secondary voltage ofa double_wound transformer (c) An independent voltage source at the nominal frequency ofthe system.
In options b) and c), the measuring voltage source is to be eafihed for the measurement. For safety reasons, when measuring voltages above 50 V, the maximum output current should be limrted
to 3.5 mA.
2
DC systen
-
insulation resistance test by using a minimum test voltage of 500 exceeding 500 V
v
DC for nominal system voltages not
insulation resistance test by using a minimum test voltage of 1000 V DC lor nominal system voltages above 500
V
The insulation resistance test shourd be made using measuring equipment
BS EN 61557-2.
in
accordance with
TEST METHOD FOR MEASURING THE IMPEDANCE OF FLOORS AND WALLS WITH AC VOLTAGE
curent, I, is fed through an ammet to the test electrode from the output of the voltage source or from the line conductor L. The voltage (U.) at the electode to Earth or to the proteciive conductor ii measured by neans of a voltmeter with an intemal resistance ofat least I Mf). The impedance of rhe ffoor insularion willthen be;
Z.:+
The measurement for ascellaining the i[.rpedance is to be carried out at as many points as deemed necessary selected at mndom, with a minimum ofthree. The test electrodes may be either ofthe ioilowing types. In ca.. oiai.f*., ,rr" use oltest electrode 1 is the reference nethod.
TEST ELECTRODE
1
The electrode comprises a metallic t pod.ofwhich the parts resting on the floor fonn the poirts ofan equilateral triangle Each suppofting poirlt is plovided with a ffexibL base giviig, when loaded, close contact with the surface being tested over an area ofapproximatery 900 mmr and preseniing a-resistance ofless than 5000
o.
Belore measurements are made, the surlace being tested is cleaned with a cleaning fluid. while measurements are being made, a force ofapproximately 750 N for floors or 250 N for wa[s is applied to the tdpod.
502
Fig 134
-
Test electrode
't
fl+
ium
al'min
]l
erare--l
flt
R:20
prohle view
view from above section of a contact stud in conductive rubber
Din?e sions
i
nliIIimetl.es
view from below
4
TEST ELECTRODE 2
The electrode conlprises a square metallic plate with sides that measure 250 mm, and a square ofdampened, waterabsorbent paper, or cloth, from which surylus water has been removed, with sides that measure approximately 270 mm. The paper is placed between the metal plate and the surlace being tested.
Dudng measurement a force ofapproximately 750 N for floors or 250 N for walls is applied on the plate.
Fig 138
-
Test electrode 2
750 N
wooden plate
I
uetal plate damp cloth
floor covering
subnoor
---
VAI_V )r.21,\i.!) ;:(<'-(r)ri -,/,
\"/\'\
_\
^7.
)
-\\.\_)
PE
APPENDIX 14 (lnformative) DETERMINATION OF PROSPECTIVE FAULT CURRENT Regulation 434.1 requires the prospective fault current to be determined at evely relevant point of an installation. Relevant points are switchgear and protective devices that may have to operate and possibly disconnect a lault curent. The devices have to be able to withstand the fault currents safely and protect downstearn equipment from damage in the event of a fau1t. Fault curents can occur in the event ofinsulation failure between live conductors and between line conductors and Earth. Regulation 643.7.3.201 requires the prospective fault current to be measured, calculated or determined by another method, at the odgin and at other relevart points in the installation.
In a three-phase installation the highest prospective fault current occws with a sinrultaneous fault between all line conductors.
An approximation of the prospective fault culTent between line conductors can be determined by a measurement between a line conductor and neutrul multiplied by
!3.
An approximation ofthe prospective fault curent due to a siurultaneous shorl-circuit faultbetween all line conducto$ is determined by measurement between line and neutral multiplied by 2.
In a single-phase system the prospective fault curent is the greater of either the fault current between the line conductor and neutral or the fault current between line conductor and Eafih.
Othel methods of determining prospective lault curent are not precluded. For installations with multiple sources ol supply, measures should be taken to detemine prospective fault curent for all combinations of supply arangernerts, so that tl're contribution made by any privately controlled embedded generation or uninterrupted supply arrangements is included.
In domestic (household) or similar premises, where a consumer unit to BS EN 61439-3 is used and the maximum prospective fault current declared by the dist butor is I 6 kA, it is not necessary to measure or calculate prospecti\ e fault current at the origin ofthe supply. When measuring prospective fault cunent, the person carrying out the testing should be aware ofthe danger present when connecting test instruments to live parts, and take suitable precautions as required by the Electricity at Work Regulations 1989 (EAWR). The HSE publication HSR25 provides guidance on this.
The measurement should always be made on the output terminals of a suitably rated protective device. lf such a device is not present then a temporary one should be fitted. Measurement should never be made where overcuffent protection is not present between the point ofco[nection and the supply transformer. Fused test leads alone do not meet this requirement.
504
APPENDIX 1 5 (lnformative) RING AND RADIAL FINAL CIRCUITARRANGEMENTS, REGULATION 433.1 This appendix sets out options for the design ofring and radial final circuits for household and similar premises in accordance with Regulation 433.1, using socket-outlets and fused connection units. It does not cover other aspects
ofthe design ola circuit
-
such as:
Protection against electdc shock, Chapter 41 Protection against thermal effects, Chapter 42 Protection against overcurrent, Chapter 43 Selection and erection of equipment, Part 5.
Fig 15A- Ring final circuit arrangements, Regulation 433.1.204 The load current in auy part ofthe circuit should be unlikely to exceed for long periods the curent-canying capacity ofthe cable (Regulation 433.1.204 refers). This can generally be achieved by;
(i) (ii)
locating socket-outlets to provide reasonable sharing ofthe load around the ring not supplying immersion heaters, comprehensive electric space heating or loads ofa similar profile fron the ring circuit
(iii) (iv)
connecting cookers, ovens and hobs with a rated power exceeding 2 kW on their own dedicated radial circuit taking account of the total floor area being serued. (Historically, a limit of I 00 m] has been adopted.) stans and In shes at the d slrbLtion board, where it s connecled overcunenl proleci ve
NOTE: Corsideraiion
protection by an RCD Regulaiion 411 3.3 An unlused spur shou d feed one single or one twin sockel-oullet
522 6 242 and 2Q3.
An unfused spur may be connecl€d io the o.igin of ihe c rcuil n lhe dislribulion board.
Spur using an FCU not connected directly to the ring The number ofsockeroutets supp ed Jrom a fused conneclion unit s dependenl upon th€ load character stcs, having iaken diversly nto account
Spur using an FcU con.ected directly to the ring The number ofsocket-out els supplied from a fused conneclion unit s dependenl upor the oad characterislics having iaken diversity into accounl
Cables should, wherever practica ble beixed in a position such lhaitheywittnoi be covered by thermal nsulation. Wherc a cable is partiatty orcomptetety covered byrhemra insuraion, rcference should be made ro Regutation 523 9.
Fused conneclion unlt (FCU)supplying fixod equipment
Fused connection unit (FCU)to BS 1363.4 Maximum fuse 13 A
aJunction box to BS EN 60670-22. Junction boxes wilh screw terminals must be accessible for inspeclion, test ng & ma ntenance or allernatively use mainienance-free term nals/ connections (Regu ation 526.3).
IL
NOTE: Conductor size re ates to BS 6004
'flattwin &earth" cable andth€ minimum cross-sectional area for the live
conductors on y i.e. L & N. Reduced circuit protective conduclor srze is perm tted .e.: Live = 2.5 mm2, CPC = 1.5 rnm2 Live = 1.5 rnm2, CPC = .1.0 mm2
Fig 158
-
Radial flnal circuit arrangements, Regulation 433'1 A rad aLfina circuit starts at the distribution board, where lt is connecled to an overcurrent protecive device' NOTE: Consideralion must be g ven to the need for add uonal prolection by an RCD in accordance with ReguLatlon 411.3.3 and Regulaiions 522.6.202 and 203'
All live conductors 2
204
30Aor 32A
overcurreni proteciive
overcurrent proiective
5 mm2
Live conductors 4.0
Unfussd spur An unlused spur run n 2.5 mmz cable should feed one single orone twin socket-outletonly. An unfused spur may be connected io the origin ofthe circuil in the
Spur using an FCU The number of socket oui ets supp|ed from 3 fused connection unti is dependent uPon the load characterisiics havlng taken divers ty
1.5 mm2
Cables should. wherever practicable, be fixed in a poslt on such thatihey will y be covered by thermallnsu ation. Where a cable is partra ly orcompleie " covereo Oy rtrirmat insuratior, reference should be made io Regulation 523" 9'
Fused connection unit (FCU) to BS 1363-4 Maximum fuse 13 A
lDJunction box lo BS EN 60670-22. J-nctior bores with screw lermlnals must oe accessible for inspection, testing & maintenance or, alternatively, use maintenance-free terminals/ connections (Regulat on 526.3).
NoTE: Conductor size relaies to BS 6004 "flaftwln & earth" cable and the minimum cross-sectional area for lhe live conductors only i.e. L & N. Reduced circuit protective conductor size is permiited i.e: Lrve = 4.0 mm2, CPC = 1.5 mmz Live = 2.5 mm2, CPC = 1.5 mm2 Live = 1.5 mm2, CPC = 1.0 mm2
APPENDIX 1 6 (lnformative) Devices for protection against overvoltage l
Typical installation of a surge protective device (SPD) in a power distribution board for a TN-S system. Fig 16A1
-
SPD connected to the first overcurrent protective device (OCPD)
to the incoming supply
: 5
:
I I
SPD
=
I I I
=
I
:=
It H
I
[-
zl
lL_ -.=-T.rrnrr1 Protective conductor Key 1
L1
L2L3
N
:
Distribution board
2 Main switch 3 Earthing bar 4 Neutral bar 5 Enclosure for SPD
6 FiISt OCPD 7
Altemative first OCPD
NOTE:
L
The OCPD provides a convenient means to protect the SPD and a means of isolation. As there is insufficient room within the distribution board the SPD is mounted in a separate enclosure for electrical safety. This enclosure is mounted directly alongside the distribution board so that the connecting leads are kept shod. An additional local bonding connection is made to further miiimize voltage dtop on the connecting leads.
507
lnstallation of surge protective devices in TT systems, Connection Type 1 (CT 1) Fig 16A2
-
SPDs on the load side ofan RCD [according to Regulation 534.4.6(a)l
I I I I I I
Key I
Distribution board
OCPD
I
Overcurent protective devices at the odgir
ofthe installation 2
Main earthing terminal or bar OCPD 2 Overcunent protecti\ e de\ ices Surge protective devices ensuring a protection level itr accordance with
oveffoltage Category
II
4a, 4b Eafihing connection of surge protective devices, either 4a or 4b, whichever is the
shorter roufe
5
Current-using equipment
6
Residual curent protective device
(RCD) 7
508
\ lnstallation of surge protective devices in TT systems, Connection Type 2 (CT 2) Fig 1643
-
SPDs on the supply side of an RCD [according to Regutation 534.4.6(b)l
I I I I I I I
: , 3a r-j---iJ : I L _ :-: --: --- --- :_ :-: -_ _
Key
I
Distribution board
2
Main eafthing terminal or bar
OCPD 1 Overcurrent protective devices at the origin of the installation OCPD
3
Surge protective devices
3a
Surge protective device (SPDs 3 and 3a in series ensuring a
2
Or ercunenl pro(eclive devices
protection level in accordance with oveNoltage Category II)
4a,4b Earthing connection of surge protective devices, either 4a or 4b. whichever is the shofter route
Current-using equipment 6
Residual curent protective deyice (RCD) installed downstream ofthe surge protectiYe devices
SPD assembly
509
lnstallation of surge protective devices in lT systems Fig 16A4
-
SPDS on the load side of an RCD
I I I I I
I I I
Open or high impedance
I I I
_l
I
7l_-
= Key
I
Distdbution board
2 2
Main earthing terminal or bar
OCPD
I
Overcurrent protective dcvices at the
OCPD 3 3
Surge protective de\ ices ensuring a protection level in accordance with overvoltage Category II
4a,4b
Eanhing connecljon ofsurge prolective devices, either 4a or 4b, whichever is the shorter route
5
Cuffent-usil]g equipment
6
Residual curent protective device (RCD) installed upstream ofthe surge protective devices
7
SPD assembly
2
Overcunenl protectire dcr ices
f"'""\ f ,o
,
."a
I
origil of the installation
urenmv E
I
lnstallation of Types
1
,
Fig 16A5
SoLrrce
2 and 3 SPDs, for example in TN-C-S systems
-
lnstallation example of Types 1, 2 and 3 coordinated SPDs
lnslallation
oc"o
+
9
L1
L2 L3 N
OCPD
2
OCPD 3
Key
1
Distributiol board
7 Surge protective device, Tlpe 2
Distribution outlet
8 Surge protective device, Type 2 or Tlpe 3
Main earthing terminal or bar
9 Decoupling element or line length
NOTE: If the cable length between the SPD types is shofi (refer to manufacturers' data), a decoupling element is employed to provide inductance for corect SPD co-ordination.
Surge protective device, Type I
Earthing connection (earthing conductor)
of surge protective device OCPD 1,2, 3,4 Overcunent protective devices
Fixed equipment to be protected
NOTE 1: For further infomation reference should be made to DD CLC/TS 61643-12. NOTE 2: SPDs 4 and 7 (or 7 and 8) can be combined in
a
single SPD.
NOTE 3: SPDs may require additional modes ofprotection for serNitive equipment. NOTE 4: BS EN 62305-,1 covers the protection ofelectrical and electonic systems within structures against lightning. NOTE 5: Section 4,13 of BS 7671 deals \1ith the protection ofelectrical installations against transient overvoltages of atmospheric oligin. transmitted b) the suppll distribution system, and against switching overvoltages generated by the equipment
\\'ithii
the installation.
I SPDs are used at the origir ofthe installation, Type 2 SPDs are used at distdbution boards and Type 3 SPDs are used near terminal equipment. Combined Type SPDs are classified with more than one Type, e.g. Type l+2, Type 2+3. Ty2e 1 SPDs are only used where there is a risk ofdirect lightning curent. Typically, Type
The most impofiant aspect ir selecting an SPD is its limiting voltage performance (protection levet Up) during the expected surge event, and not the energy withstand (e.g. I;,,,,) which it can handle. An SPD with a low protection level will provide adequate protection olthe equipmelt, while an SPD with a high energy withstand may only result in a longer operating life.
TABLE 16A
-
lnformation on SPD classification
SPD
SPD
according to BS EN 62305
according to BS EN 61643-11
SPD tested with Ir.n
Type I
SPD tested with I"
Type 2
SPD tested with a combination u ar e
Type 3
SPD tested with Iimp (BS EN 62305-4) SPDs which withstand the partial lightning cun ent (with a typical waveform 10/350 impulse test cu[ent Iimp.
pLs)
require a coresponding
NOTE 1: For power lines, a suitable test cunent Iinp is defined in the Class I test procedure of BS EN 61643- I l. SPD tested with
In (BS EN 62305-4)
SPDs which withstand induced surge currerts with a typical waveform 8/20
curent
pLs
require
a
coresponding impulse test
Jnspd.
NOTE 2: .For power lines a suitable test cunent Inspd is deflned in the Class ll test procedure ofBS EN 61643-1
1.
SPD tested with a combination wave (BS EN 62305-4) SPDS that withstand induced surge curents with a typical waveform 8/20 ps and require a coresponding itnpulse test curent T,c. a suitable combination wave test is defined in the Class III test procedure ofBS EN 61643 ll, defining the open-circuit voltage Uoc 1.2/50 gs and the short-circuit current Isc 8/20 gs ofa 2 Q combination wave generator.
NOTE 3: Forpower'lines
Table of figures
- lllustration of earthing and protective Fig 3.1 - Single-phase 2-wire Fig 3.2 - Single-phase 3-wire Fig 2.1
conductor terms (see Chapter
54)
45 46
- Two-phase 3-wire Fig 3.4 - Three-phase 3-wire Fig 3.5 - Three-phase 4-wire Fig 3.6 - 2-wire Fig 3.7 - 3-wire Fig 3.8 - TN-S system Fig 3.9 - TN-C-S (PIVE) system Fig 3.3
46 46 46 47 47 48
48
system Fig 417 -Arm's reach Fig 3.'10
TT
-
39
49 76
Fig 44.1 - Representative diagram for connections to Earth in the substation and the LV installation and the overvoltages occurring in case of faults 98 Figure 44.2 Figure 44.3
-
Flash density map of UK
102
lllustration showing the lengths to consider for the calculation of
Lp
103
Fig 44.4 - Bypass conductor for screen reinforcement to provide a common equipotential bonding system
'108
Fig 44.5 - Avoidance of neutral conductor currents in a bonded slructure by using an installation forming part of a TN-C-S system from the origin of the public supply up to and including the final circult within a building
109
Fig 44.6 - Avoidance of neutral conductor currents in a bonded structure by using an installation forming part of a TN-S system downstream of a consumer's private supply transformer
110
Fig 44.8 -
lnstallation forming part of a TT system within a building installation
Fig 44.7
Example of a substitute or bypass bonding conductor in an installation forming part of
a TT system Fig 44.9
112
TN multiple-source power supply with single connection between PEN and earth
-
Fig 44.10
111
-
TN multiple-source power supply with unsuitable multiple connection between
PEN and earth
113
Example of protective conduclors in star network
Fig 4444.2 - Example of multiple meshed bonding star network Fig 4444.3 - Exanrple of a common meshed bonding star network Fig 4444.4 - Example of equipotential bonding neh,'r'orks in a structure Fig 4444.1
112
116 116 117
without a lightning
protection syslem
1'18
Figure 46.1 - Lamp control circuit with switching in the neutral conductor Fig 534.1 - Lightning Protection Zones (LPZ) concept
120 122
FiT534.2- Example of installation
162
Fig 4444.5
Example of cable separation distance
of Type
1,IypeZ and Type 3 SPDS
Fig 534.4 - Connection Type CT2 (e.9. 3+1-configuration) for a three-phase system with neutral Fig 534.5 - Connection points of an SPD assembly Fig 534.6 - Example of overcurrent protection in the SPD branch by using a
Fig 534.3
Connection Type CT1 (4+0-configuration) for a three-phase system with neutral
'160
toJ toJ 166
dedicated external overcurrent protective device
to/
- Connection of the SPD Fig 534.9 - Example of installation of an SPD in order to decrease
'169
Fig 534.8
lead length
of SPD supply conductors
170
Fig 536.2 -
Selectivity between OCPDs
172
Selectivity between RCDS in case of residual current
173
Fig 536.1
174
- Selectivity between OCPD and RCD using RCBOs Fig 536.4 - Selectivity between OCPD and RCD using RCCBS Fig 536.5 - Selectivity between upstream RCCB and RCBos Fig 536.6 - Typical configuration for combined short-circuit protection of OCPDs Fig 536.7 - Co-ordination between OCPD and contactor in case of short-circuit Fig 536.9 - Co-ordination between OCPD and switch Fig 536.10 - Co-ordination between OCPD and RCCB Fig 536.11 - Selectivity with oCPD and undervoltage relays
Fig 536.3
174
175 176 177
178 179 214
- Auxiliary circuit supplied directly from the main circuit Fig 55.2 - Auxiliary circuit supplied from the main circuit via a rectifier
Fig 55.1
214 214
Fig 55.3 -Auxiliary circuit supplied from the main circuit via a transformer Fig 55.4 - Configuration of an auxiliary circuit Fig 701.1 - Examples of zone dimensions (plan) Fig 701 .2 - Examples of zone dimensions (elevation) Fig702.1- zone dimensions for swimming pools and paddling pools
-
Fig 702.2
Fig702.4 Fig702.3
Fig 703
218 243 244
250 251
zone dimensions for basin above ground level 25m Example of zone dimensions (plan) with fixed partitions of height at least Example of determination of the zones of a fountain
zcz 253 255
zone dimensions for a sauna
-
- Example of supplementary equipotential bonding within a cattle shed the caravan Fig 708 - Example of a 2-pole and protective conductor supply system between caravan or motor
262
Fig 705
pitch
268
supply equipment and the caravan Figs 709.1 & 2 - Examples of methods of obtaining supply in marinas Fig 709.1 - Connection to a single-phase mains supply with RCD Fig 709.2 - Connection to a three-phase mains supply with RCD Fig 709.3 Example of an instruction notice to be placed in marinas
273
273 273
-
282
Fig710.1- Example of patient environment (BS EN 60601) F tg 710 .2 - fypical theatre layout
zoJ zoJ
- Typical medical lT system arrangement Fig 712.1 - PV installation - General schematic - One array
Fig 710.3
ao1
292
PV lnstallation - Example with two or more arrays =ig712.2generating set located inside the unit, =ig 717 .1- An example of a connection to a low voltage ,r th or without an earth electrode = .717 .2
-
301
302
Reserved for future use
==-'-3AnexampleofaconnectiontoaiowVoltageelectricalsupplyexternal'totheUnltinwhich installation or a
: : _:=:i ,,e measu res are effective, the supply derivld from either a fixed electrical 3o2 :---'=-.')set with or without an er.tn electiode at the unit . . .- : - -- :xample of a connection to a low voltage electrical supply externat to the unit, derived : - : - :- : ' , = I 3 ectrical jnstallation or a generating set with any type of earthing arrangement 302 ,
-
-;:
:: :-:.'.'.:'
*a;q*
r' .
,9lg '
--: :': -- ' .
-
'-
r:_
.
.-.
.-
'^. - svstem with an insulation
monitoring device and automatic with earth electrode trt the occunence of a first fault, -'=
303
a connection to a low voltage electrical supply external to the unit, with any 303 using an internal TN system with simple
separation
)=*:eni
e of a connection to a low voltage electrical supply external to the unit, with
- : - : a. s n installations - - - . -' ,. :- s in installations .'.
electrode
of a @nnection to a low voltage electncal supp/y externa/ to the unit using
''.- .: :' =" =-
lTsyitem, with an earth
'. ..-- -a arrangement using simple separation in m ttre occuirence of a second fault : - :: :-s for electrlcity supply --
'
:
aqd an internal
with an internal lT system with automatic.
with protection by barriers or enclosures
with protection by obstacles
304 308
32'l
areas
Examples of positioning of doors in closed restricted access Case Fig A72g.1- Minimum passing width in case of evacuation Case Fig 4729.2 - Minimum passing width in case of evacuation Fig A730.'1 - Direct connection to a single-phase mains supply with an isolating transformer on Fig A730.2 - Direct Gonnection to a singte-phase mains the Fig 4730.3 - Direct connection to a three-phase mains supply with an isolating transformer f ig RZaO.+ - Oirect connection to a three-phase mains the vessel Fig 753 lnformation for the user of the
Fig 729.3
-
1 2
supply
vessel
-
supply
installation Fuses to BS 88-3 fuse system C Fig 3A2(a) - Semi-enclosed fuses to BS 3036 Fig 3A2(b) - Semi-enclosed fuses to BS 3036 Fig 3A3(a) - Fuses to BS 88-2 fuse systems E and G Fig 3A3(b) - Fuses to BS 88-2 fuse systems E and G Fig 3A3(c) - Fuses to BS 88-2 fuse system E - Type B circuifbreakers Fig 3A5 - Type C circuit-breakers Fig 3AO - Type D circuit-breakers Fig 9
-
324
328 328 329 32g 338
364 365 366 367
368 369
to BS EN 60898 and RCBOs to BS EN to BS EN 60898 and RCBOs to BS EN to BS EN 60898 and RCBOs to BS EN
Explanation of symbols used within Appendix
324
on
3A1 Fig -
Fig 3A4
323
61009-1 61009-1 61009-1
9
370 371 372 489
protective conductor and neutral conductor to Fig 9A-TN-C-S multiple source system with separate 489 current-using equiPment and no neutral Fig 98 -TN multiple source system with protective conductor 490 load 3-phase or for 2co"nductor tnroughout the system 491 in groups or indlvidually Fig 9C - lT system with exposed-conductive-parts earthed L- separated from the protective conductor Fig 9D - TN-S DC system with earthed line conductor 491 throughout the installation M separated from the Fig 9E - TN-S DC system with earthed midpoint conductor pr6te"tiu" conductor throughout the installation protective conductor Fig 9F - TN-C DC system with earthed line conductor L- and 492 installation the in one sinile conductor PEL throughout
"o"rOin"O
M and protective conductor combined in Fig 9G - TN-C DC system with earthed midpoint conductor 493 one single conductor PEM throughout the installation
FiogH-TN-C-SDCsystemwithearthedlineconductorL-andprotectiveconductorcombinedinone 4e3
:;X##:;;;;nji",tn,jitr." instarration
Figgl-TN-C-sDcsystemwithearthedmidpointconductorMandprotectiveconductorcombinedin494
one single conductor PEM in a part of the
installation
494
-TT DC system Fig gK-TT DC system
Fig 9J
495 protective
conductor
- lT DC system with eafthed line conductor L- and M and protective conductor Fig 9M - lT DC system with earthed midpoint conductor is provided for Fig 10A - Circuit in which an overload protective device in parallel
Fig 9L
each ofthe m conductors is provided for Fig 10B - Circuit in which a single overload protective device the m conductors in Parallel Fig 1OC - Current flow at the beginning of the fault protective device c' Fig 10D - Current flow after operation of the end of the parallel Fig 10E Linked protective devices installed at the supply
Fig 13A - Test electrode 1
L-
ir'l
Fig 13B
-
Fig 1 5A
-
Test electrode
2
Ring final circuit arrangements, Regulation 433
495 496 498 499 499 500
conductors
500 503 503
1'204
505
Fig 158
-
Radial final circuit arrangements, Regulation 433.1
Fig 1641 - SPD connected to the first overcurrent protective device (oCPD) to the incoming supply
- SPDs on the load side of an RCD [according to Regulation 53a.a.6(a)l Fig 1643 - SPDS on the supply side of an RCD [according to Regulation 534.4.6(b)] Fig 1644 - SPDS on the load side of an RCD Fig 1642
Fig 16A5
-
lnstallation example of Types 1, 2 and 3 coordinated SPDS
5Ub
507 508
509 510 511
Table of tables
times
59
lvlaximum earth fault loop impedance (Zs) for fuses, for 0.4 s disconnection time with Ugof 230 V (see Regulation
61
TABLE 41 .3 - Maximum earth fault loop impedance (Zs) for circuit-breakers with U0 of 230 V, for operation giving compliance with the 0.4 s disconnection time of Regulation 411.3.2.2 and 5 s disconnection time of Regulation 411 .3.2.3 (for RCBOs see also Regulation
62
TABLE 41 ,4 - Maximum earth fault loop impedance (2") for fuses, for 5 s disconnection time with Uoof 230 V (see Regulation
63
TABLE 41.5 - lvlaximum earth fault loop impedance (Zs) for non-delayed and time delayed 'S' Type RCDS to BS EN 61008-1 and BS EN 61009-1 for Uoof 230 V (see Regulation
64
TABLE 41 ,6 - Maximum earth fault loop impedance (Zs) for 5 s disconnection time and (single-phase) and 63.5 V (three-phasexsee Regulations 411 .8.1 .2 and 411
68
TABLE 41 .2 TABLE 41.1
l\4aximum disconnection
411.4.201)
411.4-204)
411.4.203\
411.5.3)
.8.3)
U0
of 55 V
TABLE 42. 1 - Temperature limit under normal load conditions for an accessible part of equipment within arm's reach
85
TABLE 43.1 - Values of k for common materials, for calculation of the effects of fault current for disconnection times up to 5 seconds
93
*
TABLE 44.1 Power frequency stress voltages and power frequency fault voltage in the low voltage system
IABLE 44.2
-
Permissible power frequency stress voltage
'f ABLE 443.2 TABLE 443.1
Calculation of fen,
103
Required rated impulse voltage of equipment (Uw)
105
TABLE A444.1 - Summary of minimum separation distances where the specification and/or the intended application of the information technology cable is not available
-
TABLE 4444.2 TABLE 51
-
Minimum separation between power and signal cables (m)
ldentification of conductors
- Maximum operating temperatures for types of cable insulation TABLE 52.2 - Cable surrounded by thermal insulation TABLE 52.3 - l\,'linimum cross-sectional area of conductors TABLE 53.1 - Correlation between the maximum value of earth resistance RAand the maximum rated residual operating current lxnofthe
RCD
- Sizes of tinned copper wire for use in semi-enclosed fuses TABLE 534.2 - lvlinimum required U"ofthe SPD dependent on the supply system configuration Table 534.3 - Nominal discharge current (lnspd) depending on supply system TABLE 533.'l
Type
142
144 144 156 159
164 165 '165
TABLE 534.5
168 181
188 190 195
bunched with cables, or for seperate bare protective conductor in contact with cable covering but not bunched with cables, where the assumed initial temperature is 30'C
197
TABLE 54.3 - Values of k for protective conductor incorporated in a cable or bunched with cables, where the assumed initial temperature is 70 'C or greater
197
TABLE 54.5 TABLE 54.4
I
119
TABLE 534.4 - Selection of impulse discharge current (l;.0) where the building is protected against direct Iightning strike
- Connection of the SPD dependent on supply system TABLE 537.4 - Guidance on the selection of protective, isolation and switching devices TABLE A53.1 - Devices and associated functions TABLE A53.2 - Device co-ordination in a LV electrical installation TABLE 54.1 - Minimum cross-sectional arca of a buried earthing conductor TABLE 54.2 - Values of k for insulated protective conductor not incorporated in a cable and not
t""" |
119
131
TABLE 52.1
and connection
98 oo
Values of k for the sheath or armour of a cable as the protective conductor
197
Values of k for steel conduit, ducting and trunking as the protective conductor
197
.:. --,
TABLE 54.6 * Values of k for bare conductor where there is no risk of damage to any neighbouring material by the temperature indicated
198
TABLE 54.7 - Minimum cross-sectional area of protective conductor in relation to the cross-sectional area of associated line conductor
198
TABLE 54.8 - Minimum cross-sectional area of the main protective bonding conductor in relation to the PEN conductor of the supply
203
-
TABLE 55.1 TABLE 55.2 TABLE 64
-
211
l\4inimum cross-sectional area of copper conductors in mm2
216
Minimum values of insulation resistance
TABLE A710 TABLE 721
Plugs and socketoutlets for low voltage circuits
-
TABLE A721 con nectors
-
232
List of examples
284
Minimum cross-seclional areas of flexible cables for caravan connection
-
310
Functional allocation and cross-sectional areas of cores for caravan 313
TABLE 3A - Time/current performance criteria for RCDS to BS EN 61008-'l and BS EN 61009-1
363
- Voltage drop TABLE 4A1 - Schedule of lnstallation lvlethods in relation to conductors and cables TABLE 4A2 - Schedule of lnstallation methods of cables (including Reference N4ethods)
379
for determining current-carrying capacity
386
TABLE 483 -
TABLE 4Aa
Rating factors for triple harmonic currents in four-core and flve-core cables
TABLE 4Ab
oo.)
cot
TABLE 4A3
Schedule of cable specifications and current rating tables
5v5
TABLE 4B2
Rating factors (C") for ambient ground temperatures other than 20 'C
394
Rating factors (C") for cables buried direct in the ground or in an underground conduit system to BS EN 50086-2-4 for soil thermal resistivities other than 2.5 K.miW to be applied to the current-carrying capacities for Reference Method D 395 TABLE 484 - Rating factors (Cd) for depths of laying other than 0.7 m for direct buried cables and cables in buried ducts
395
- Rating factors for cables having more than 4 loaded cores TABLE 4C1 - Rating factors for one circuit or one multicore cable or for a group of circuits, TABLE 485
395
or a group of multicore cables,to be used with current-carrying capacities of Tables 4D'lA to 4J4A
396
TABLE 4C2 - Rating factors for more than one circuit, cables buried directly in the ground Reference lVlethod D in Tables 4D4A to 4J4A multicore cables
-
TABLE 4C3 - Rating factors for more than one circuit, single cables in ducts buried in the ground Reference N,4ethod D in Tables 4D4A to 4J4A (lVulticore cables in single-way ducts)
397
-
TABLE 4C4 - Rating factors for groups of more than one multicore cable, to be applied to reference current-carrying capacities for multicore cables in free air- Reference Method E in Tables 4D2A to 4J4A TABLE 4C5 - Rating factors for groups of one or more circuits of single-core cables to be applied to reference current-carrying capacity for one circuit of single-core cables in free air - Reference Method F in Tables 4D1A to 4J3A 399
- Rating factors for cables enclosed in infloor concrete troughs (lnstallation Methods 118 to 120 of Table 4A2)
TABLE 4CO
TABLE 4D1A - Single-core 70 'C thermoplastic insulated cables, non-armoured, with or without sheath (COPPER CONDUCTORS) TABLE 4D1B
-
VOLTAGE DROP (perampere per metre)
TABLE 4D24- Multicore 70'C thermoplastic nsulated and thermoplastic sheathed cables, non-armoured (COPPER CONDUCTORS) TABLE 4D2B
-
VOLTAGE DROP (per ampere per metre)
400 401
402 403 404
TABLE 4D3A- Single-core armoured 70 'C ihermoplastic insulated cables (non-magnetic armour)
405
TABLE
4D4A- Multicore armoured 7C 'C ihermoplastic insulated cables (copper conductors) TABLE 4D5 - 70 'C therrnop asr c -s- a:3d and sheathed flat cable with protective conductor
407
(COPPER CONDUCTORS
409 523
TABLE 4E1A - Single-core 90 "C thermosetting insulated cables. non-armoured, 411 with or without she5tn lcoeeen TABLE 4E24- Multicore 90 "c thermosetting insulated and thermoplastic sheathed cables, 413 non-ir.out"O (COPPER CONDUCTORS) TABLE 4E3A- Single-core armoured 90 "C thermosetting insulated cables (non-magnetic armour) 415
CoNDUCTORS) -
4E4A- Mutticore armoured 90 "C thermosetting insulated cables tcoFFen TABLE 4F1A- 60'C thermosetting insulated flexible cables with sheath, non-i*orreo (CoPPER CoNDU6ToRS)
TABLE
Conoucrons)
417 419
TABLE 4F1 B - VOLTAGE DROP (per ampere per metre): Conduclor operating temperature: 60
+tu
TABLE4F2A_g0.Candls0.Cthermosettinginsulatedflexib|ecablesWithSheath, non-irmoured (COPPER CoNDUCTORS)
421
'C
TABLE 4F3A
-
Flexible cables, non-armoured (COPPER
CONDUCTORS)
423
TABLE 4G1A- Mineral insulated cables thermoptastic covered or bare and exposed to touch
sHEATH)
rcoFFen ConoucroRsnND TABLE 4G2A- Mineral insulated cables bare and neither exposed combustible materials (COPPER CONDUCTORS AND TABLE 4H1A
-
Single-core 70
to touch nor in contact with
SHEATH)
"c thermoplaStic insulated cables, non-armoured, with orwithout
cououcrons;
.r,""tn lAruvrr.rruM TABLE 4H24- l\4ulticore 70'c thermoplastic insulated non-armoureo (ALUlVllNlUl\4
CONDUCioRS)
TABLE 4H3A- Single-core armoured 70
'c
and thermoplastic sheathed cables,
thermoplastic insulated cables (non-magnetic armour)
CoN"DUCToRS) TABLE 4H44 - Multicore armoured 70 'C thermoplastic insulated cables inlwrnruM coNDUCToRS) tn[wrnrurr,l
TABLE 4J1A- Single-core 90 sheath (ALUN4INIU-M
"c thermosetting insulated cables, non-armoured, with
CONDUCTORS)
427 429 431
4s3 435
or without
TABLE 4J2A- Multicore 90 'c thermosetting insulated and thermoplastic sheathed cables, non-armoured (ALUMINIUM CONDUCTORS) TABLE 4J34- Single-core armoured 90 'c thermosetting insulated cables (non-magnetic armour) ALUMINIUM CONDUCTOR
43t 439 441
CONCISE LIST OF EXTERNAL INFLUENCES
446
A ENVIRONMENT:
447
B UTILIZATION:
458 460
C CONSTRUCTION OF BUILDINGS:
TABLE 7A- Example of conductor marking at the interface for additions and alterations to an AC installation identified with the old cable colours TABLE 78 - Cable to BS 6004 or BS 72'11 (flat cable with bare cpc)
- Standard 600/1000V armoured cable BS 6346, BS 5467 or BS 6724 TABLE 7D - Flexible cable to BS EN 50525 series (supersedes BS 6500) TABLE 7E - Example of conductor marking at the interface for additions and alterations TABLE 7C
DC installation identified with the old cable colours
TABLE
524
425
l6A-
lnformation on SPD classification
4U 485 485 485
to a 486 512
INDEX
Abmsjon, damage to
to
due
wiing
systems
522'61 '/t'7 52.2(il)
721.522..1 Abbreviations used in the Standard Pafi 2 521 5'2 AC, types ofcable not suitable Accessibiliq/ -
-
accessibilitY bY livestock automaticdisconnection buried cables cattle sheds
1
for
connections and joints
526.3
enrelgency srvitching equipment
537 .3.3.6
off
Accessories concealed cables io selection and erection Accessory. delinition
-
emergency switching, siting devices for
543.3.2 Sec 410
Additional protection fault 410.1 2
outlets
i.411.3.3
'701.115.2 4r 1.3.3 701.411.3.3
4l
1.3.4
41 1.3.3
exhibitions. shol s and stands heating cables and embedded
711.411.3.3
heating svstenls mobile and transpoftable not as sole means rcsidLral oPerating culaent
753.415.1
u
ts
7
531.3.6 703.411.3.3
socket-outlets. mobile equipment ,111.3.3 outdoors 7t4.41!,.3.3 streel fumittue Sec 702 swimning pools socket-oLil1ets. mobile equipl1lent
d.i"ai," use ofRaDs
temporary installations at fairgrounds. etc. RCDs on llnal circuits
-
sUoDlemellIall' equipotelltiaL
bonding
rrhireiire.tock
verifi catior of effectiveness
411 .3.3
equipment in genelal
wiling ofcam\ans
Additior'ls to instilllations
firc see Firc alartfi sysIe}f,l.s installations .t€e fo lnge Band definition Alterations to installations
1,
Aitemative supplies, warning notice Aluminium conductors - as PEN conductor in cofltact with oiher metals
Pafi 2
I
132.16 641.5
I
644.1 .2 514. 15.1
543.4.201 522.5 524.1
702.415.2 Sec 702
740 415
Amendments to lhe Regulations Preface PaA2 Amusement device, deflnition
1
-40.415 2 643 8
t32.16 641 .5
641.t.2 Adr,erse condilions precautions in
socket-outlet qircuits to be protected 705.411.1(i), (ii) by RCD 705.553.1 - socket-outlets. selection Appx 2 ltem l(v) - statutory regulations - supplemenlary bondirg conductors, 705.544.2 protection of - supplementary bonding for 705.415.2.1 niotecton of livestock 105.522 - *iiing systems mam systems, Air conditioning 4| .3.1 .2 bonding of the ol equipment electrical Aircraft, 110.2(vi) Regulations not applicable to
neutral Ambient temperature - cables and conductors - cables, rating factors
where specified as part ofprotective 410.3.2 [leasure Additional protectior (lrechanical) -
-
105.422 705.414.4 705.411.1 705.422.7
protection bY SELV or PELV residual curent devices in
minimum cross-sectional area of
ol
neasures
5t2.) Sec
52:
Parl
7
1
Frq'05 105.522
overhead lines and cables plotection againsi fire
-
i7.415.1
415.1.I
outdoors swimming pools suoDlement3r! equiPotential
705'415'2
Alarm -
4t5.t.2
satlnas
-
ol
-
Sec 415 70
105.512.2
metallii erids - in floor", bondin!
Pan2
bathroons RCDs tbl all circuits - suPPlernentan equlPotential hondrns. alld omi!sioll of exception f;r cefiain socket-outlets RCD. protectiotl b) - bathrooms. all circuits - domestlc lighting circuits - exceptioll for certain socket-
705.53',7 .2
705.422.6 heating appliances, fixing of '7 05.537 .2 isolation. devices for 560 6 for705 life support oflivestock, systems
Sec 553
Drorectior '
of
equipment protection
522.6.202(t)
as addition to basic and 01
Fig 705 105.512.2 705.1
dwellings
513.1
of
705.411 705.522 '705.512.2
dairies
t32.t2
protective conductor con11ectiol1s Accessible conducti\e Parts. fundamental rnl"'
Table 4A2 (No 35) Sec 705 '705.513.2
Aerial cables Agricultural Premises -
A
- definition
522.1
Appx 4 sec 2.1 Pafi 2
Amusernent parks see Faitgrowtds
Appliance, definition Appliances flre hazard frorn
-
flexible cables for
Patt 2 Sec 421
521.9 53.1.7 701.55 553.1.7 5
-
in bathrooms mobile. connection of oorlable see l'lobile eqttiptnent
sledm 424'l 463'l suitchinp lor Arc fault ditection devices (AFDD) - coordiration with overcunent producing hol u ater or
protective
devices
512 6
i
I
recommendation for use
Alcing - injury from - ofswitchgear
Arc resistant material.
Llse
of
42t.1.'/
-
l3 t. t(vii) 421.1.3
-
12t.t.3
application
4t7
-
definition
Paft 2 F
-
electric dodgems Armoured single-core cables
1
-
is 411
Atmospheric origin protcction against over,,oltage due to Authorized peBons - access to switchgear, limited to
-
point
ll
Part
-
557.3
scope
557.1
deflnition
Pafi 2
requirements for
536.4.2.21o 4
I circuits defi i|ial1) -
Band
3
422.2.2 Table 4A2 (see m under)
4l
4t1.3.2.3 & 4 411.3.2.2 to 4
dlso Voltage
Part 2
definition)'
-
segregation of. flom other circuits Bare conductors as overhead lines cables connected to
-
Part 2 528.1
528.1
4l'7.3
eiecffomechanicalstresses
identification
Bare live parts placing out of reacl)
1.3.1 .1
disconnection times - dist bution circuits - final circuits
fsee
segregation of, from othel circuits Band II circuits /see also Voltage
Sec 443
devices for
hlghway porver supplies reduced low vollage systems where cannot bc achievcd
55 7.3.1
requiremenls fot
113.1
411. I 411.1 Sec 531
equipment allowed description of prctective measure
general
Back-up protection -
installation methods Automatic disconnectioo of supply - Sec 411 4 r0.3.3(i) - application of 411 .2 basic protection, requitements for circuit protective conductor to each Class
for measuelnent functional considerations
B
740.410.3.5 521 .5.2 523.201
Assemblies ofequiPment, to comPlY
with approp ate standards Assessment of general characteristics
551.4.1
Table 55.2 557 .3.201 557.5 557.6
control
Arm's reach
-
conductor crcss-sectional area for
-
4l'7.3.1 414.4.5 Part 2
SELV and PELV circuits Barrier, definition Barriers
-
Table 41.1
fire
521 .2
protection bY -
416.2 416.2.) 416.2.2
-
degrces ofprotection
-
inspection of intermediate" il1 enclosures
-
openings in
4t6.2.1
removal or opening of
4t6.2.4
-
securing
7t4.4tt.202 411.8.3 41 1.3.2.5
411.3.1.1
extmneous-conductive-Paft s, main 411.3.1.2
generating sets
551.4.3
highway powcr supplies in case of fault
'7
1
41t.3
4t1.3.2
4|.7
-
411 .3.1.2 equipotentialbonding 41 1 .8.3 rcduced low voltage systems socket-outlets, additional protection by RCD 411.3.3 exceptions permitted 4r 1.3.3(i) not exceeding 32 A special locations, particular
Automatic sources, safety seNices
of
Auxilialy battoies fot caravans
555.1 Sec 721 Aunex
Auxiliary circuit. def nition Auxiliary circuits -
Part 2 Sec 557
use
416.I
paint, vamish or lacquer, l1ot suitable as
41t.7.4
643.'7
supplies
-
-
street fumiture
Auto-reclosing devices Autotransfonners - FELV source, not for
416.2
basic insulation oflive parts
560.4.1 5 31.1.1
-
testing
14.411 .2.201
Sec 414 and SELV or PELV baniers or enclosur-es, Iequirements
- deflnition - fundamentalprinciple - genelal requircments - iD FELV systems - in rcduced low voltage systems - live pafis, basic insulation of - methods of. checking - non-conductinglocation - obstacles for, only where controlled
Paft 7 114.41r
.201
416.2.3 Part 2
for
]l.3.1.1
-
requirements for
.2
418.3.I
411.3.3(ii) 410.3.3 Note 4
of
14/|
Rasic insulalion. defi nitiol] Basic protection - and ar:tomatic disconnection of Sec 411 supply - and double or reinforced insulation Sec 412 Sec 413 - and electrical separation
t4.41L202
in FELV systems inspection of methods of protection 642.3(viii)
mobile equipment outdoors, RCD protection required most commonly used measure protective - earthing
416.2.1(111) 1
exposed-conductive-parts. earthing
bonding to fault protection. requireme[ts for
642.3(viiiXb) 4t)..2.2.3
Sec 419
of
526.4 521.5.201 514.4.2 514.4.6
A
4l6.1Note Part 2 t3 t.2.1 410.1
41t.7.2 4t 1.8.2 416.1
642.3(viii) 4t8.1.1
417.1 &2 or supervised placing out ofreach. brre lire psns 4 l7. r not io be $ ithin arrn ' rcdch Sec 416 - provisions for Basic protection and fal t protection -
-
cables, wiring systems
ptoviding
412.2.4.1
-
pro!iding
-
4
-
41t.3.1.2
Boxes - for connection ofluminaires - for use in hollow walls - junction. circuits terminated in Bleaking capacity - overload protective devices
-
559.s.l(viii) 422.5 Note 521.8.3
fault current protective devices 434.5.t
701.512.3
701.5t2.2
socket-outlets supplementary equipotential bonding
70t.512.3
switches
701.512.3
towel rails
701.55(ix)
zones
701.32 Fig 701.1 Fie 701.2
721AnnexA
560.6.10 560.6.1 I
stationary installations incorpoiating
as measure against
551.8 I,
Patt 2 522.8.3 7
09
.512.2(ii)
'702.11
415.2
705.1152.1 705.541.2 441.4.2 444.5
EMI
batfuoorns caravans
701.4t5.2
conductor'.dellnition conductors - main
Part 2
-
&3
70t.4 | 5.2
Sec
swimming pools Bonding /see a/so E4tipotentiol bondingl - additional protection - agriculturalpremises
-
sheath
702.4t5.2 702.55.t
533.3 536.4.2
-
-
telecomn)unication cable, metallic
523.201
70t.414
definitkrt
-
-
armoured cables
SELV or PELV used in SELV socket-oLrtlets shaver supply unit
Bends in wiring systems Body resistance, reduced marinas
-
-
supplenentary see Additional prolection ; SupplenentaD) ecl ipotet1tiaI bondij1g swimming pools
701.512.3
Bcll circuits see Lbltage Band
-
-
pull-cord switches
Battedes - auxiliary, fol caravans - for safety sen ices
-
single-core metal-sheathed or
r0.3.2(ii)
protective measures pro\ idtng both. for geltet al appltcatroD 410.3.3 BathoolDs- installatiors i11 Sec 701 - additional protection - by RCD fol all low voltage circuits 701.411.3.3 - suppiemeDtary equipotelltial bonding 70t.415.2 - controls 701.512.3 - current-usingequipment 701.55 - elect cal separation 701.413 - floor heating 10t.7 53 - heating appliances, water 701.55(x) - IP requiements 701.5t2.2 - lumi1laires 701.55(xi)
-
-
enhanced protective provisioll
121 .41 I .3 .1 .2
4t L3.t.2 544.t
protective selection and erection
of
Sec 544 Sec 544
supplemeDtary sizing 544.2 connections, wanling notice at 514.13.1(ii) eanh-free local 418.2 equipment in electrically sepalated clrcutts 418.3.4 instafltaneous watel heaters lighhing protection systems 4l 1.3. 1 .2 542.4.1(iv) local supplementary 4t5.2 mair1. to extraneous-conducti!e pads
network. dcfinitioll outdoor lighting insrallations. nrefallic structures need not be bond"-d
British Standards
- additional requirements ofother - conpliance with - exclusions from Scope - refe.cnce in this Standard, list B lding materials, fire hazard from equipment
assured
522.8.14
Building site.iee Corsttltction site
definitior
Bunched, Buried cables s€e Cables, btried, Undetgrtund cables
Bums, plotection
agaimt
Busbars and b sbar connections cables connected to b
-
sbars
Par,t 2
Sec 423
526.4
colour identilication of protective
conductor of
-
selection
514.4.2
52L4
Busbar trunkilg system, definition Part 2 Busbar trunl
-
oinent-carying capacity
Appx
e1tclosure as protective conductor
543.2.2
rating under fault conditions
43,1.5.3
standard for
voltage drop Bypass bonding conductor, definition
8
521.1
Appx
8
Pa\12
C Cable channel, definition cleat, definitiorl
-
-
concertric, installation of coupler, definition couplers FELV system reduced low voltage circuits selection covers ducting bends
-
definition erection of insulating, for electrical separation
Pan 2
-
714.411.3.1.2
ducts bends
4l 1.3.1.2
Appx I Sec 420 Sec 421 Sec 422
Building, nenciration of, load bearins ' integrrty to bc
110.1.3 Sec 511 110.2
-
Pafi 2 Part 2 543.4.7 Part 2 553.2
4tt.7.5 411.8.5 553.2.1 522.8.10 522.8.3 Part 2
52242 413.3.5
prctective coflductols formed by 543.2.7 sealing at fire barriers 52'7.2 selection of 521.6 522.8.3
3
-
, , -
-
ingress
ofwater
enclosur-es
-
s22.8.10
-
AC cir.clrits in steel
52L5.2
arection
522.8 543.2.10
prohibition as pEN conductor fle\ible. delinirioo lidder, deflnitiorl iuppofis irat,.
-
522..1.1
underground
Pan 2 Patt 2
s2t.10.202
-
separated circuits
Appx 4
-
use
Part 2
for life safety systems glouping
521 .5
-
heating
-
xt conduir aod ducting
5
Pafi 2
irLlnkitr! {er r7r,til7g n..vcrrr runnei. de6nirror)
aables -
705.r2 5)2
t
Appx 4 scc 2. I 52t3.2.5
113.3.4 418.3.6
of
-
delirition
- aI,]11our as protective condLlclol. - attack by fauDa - bends - btLrred.rr.e rrli.r L,rrlergrouttLl
559.5.2 Table 4FiA 528.1 521.9
floor-warming
&
522.'1.2
- nass supportable by pendant - segregatioD ofcircuits in - selection of
-
522.8.4
- AC. types for - agticultural installations - ambienl temperature
lurniDaires
521.9.1
554.4.4 753.511
560.lr 523.5
Appx 4 sec 2.3
idertificationofcores tnlonnatioD technology. millimum separation distances
5)2.10 522.8.3
-
4441.4
in ground 1.ree.rlv, Lhtdetgnuud
433.1.203 522.8.10
-
-
damage by -
-
Dechanical str-esses solar radiation \,ibration
conditions extemal influences erh.a-tow voltage systems
^ alanr - hre - nre bgrTter\
_ nre-sc!rceatcd
-
flexible
appliances. fbr
ceiling
rneral-shearhed, sinqle_core
-
bonding nethods ofinstallation
52t.5.1
noD-metal-enclosed. as basic
protection alld fault protection
52t.5.201 528.1 Note 2
Don-sheathed, to be enclosed oD construction sites overhead between bLiildings. etc.
522.4
parallel
Sec 522
-;2 8.
t \ore
52-.
L
52
2
-
- i.5
ratiDg factors reduced neutral
road-walming
- saf'ety services - sealing at fire baniers - segregatiojl ]r.orn other electrical
1 6
s)lo
-
i.7
atrd non-electrical services selcction and erection
559.5.1.201
Appx 4
equiplllcl1t, connections to
Tables 4FiA to Sec 526 521.9.1
522.t 709.s21 522.6 to
8
512.2.2(vr) 542.2.5
543.2.1(v) 543.2.5 523.201 Sec 521
Tabie 4Al Table 4A2 523.6 Sec 52,1
412.2.4.1 521.10.1 704.s2 417.3
Appx t 0
i
tbr nlobile or n.anspofiable unrts. supPt) COnnection 7t1.52.1 identification ofcores 5lzl.3
522.6.201 522.6.202 to 204 Sec 526 528.3.5
434.4
414.4
current-cal.rying capacity
fixcd wiring. use fol
-
neutrals
553. r.oses
metal co!eri,tgs as protective
522.8
521
-
joints
s22.)1
cornparrrrr..nt. u irnrn 517.
propagarron
e
uo ductors
s22.6
n\rngs ree si/pp.r/./r flarnc
-
s22.10
- elech.onragnetic effects - elect.omechanical stesses - enler-qency lightjng - enclosures! iD onerolls dust
-
522.5 Sec 523
Appx 4
irrpact
instllled rrnder.floors or abo!
- Iow teDrperatures, in - marinas - mechanical stresses - lnetal coverings as earth electrodes
core idcntiflcation 51,1.3 cOl'rosive Of pOljltttD-l.I SubstanCes ln
cu[ent-canyjng capacity
-
ccllrtrgs in walls or partitions
-
Sec 526
-
in saunas
522.8.10 523.3 703.52
lift welts
526.4
f'auna
-
522.6.202 to 104 132.6. Sec 524
l14.l.4
contact \t ith
-
708.s2t.7 Sec 514
bu\bars conDections
Table A44zt.l 433. t.203
523.3
- caravan parks - colour identificatioD - co ceclcd t ualls or partitiorr\ - rOUdLlctOrs, crOsq-\ectiOnal ateC of - connected to bare coltductors or
554.4 Scc 753 Sec 514 522.8
523.7
Appx 4 554.4.2 & 3 Sec 753 528.1 Note 2
521.t Sec 528 Chap 52
.ingle-corc rnerat-ihealhcd.
4FiA
bonding rfujpl0l - solr $arnlng 554.4.2 & J i - solar radiarion. exposcd to s!:.]I*." s22.ll . supnorts. gcncral g2.s_4
-
rctecon'IllLl11tcatlon .re.,
liil ecomm un i catIon c i-c u i ts
&
5
I
I
tenllreratures
fd
!olragc IirniiariL,rl
.!cd Ien4teratut'e
tenllinations
Sea 526
521.9
'table 4A2 (Nos 100-
-
thernlal irsulation. io
-
underground sae
-
vibration
-
voltdge drop
-
watel or nloisture in contact with
cr1L|gs. cablcs abore. nechanical
(
eil1u95.
clarnagc
/o
121.522.1 Sec 525 Appx 4 sec 6 522.3
Capacitor, Caravan.
conrpcNation
wamirg label
r'equiled
definition Calavan installations - accessoies - additional protectioD by RCD - bonding - cable suppor-ts - conlrcctol.s - extm-low voltage -
inlets
instluctiom lor use
462.4 559.7 559.7 116.2.5 Part 2 Sec 721
721.55.2 721.415.1 721.:t11.3.1 721.522.8.1.3
7)1.55.2.6 Fig 708 721.414 Scc 721 Arlnex A 721.55.I '/21.5).4.t F
-
isolation l-P(; compaftrrent
i,g'721
121.537.2 721 .528.2. r
A721.528.2.5
-
proteclion against elcct c shock scope
olapplication
wiring
'121.11
'72t.t 72).521.2 721.522 Pal1 2
iott
708.415.1
Caravan pitch. definilion Calavarl pitch electical supply
Part 2
de{inilion
arrlidge firse 1ink, dcfiuition f atenary wires Cathodic protection syslems, Rcgulatiolls not applicable to DC C
708.5r2.2 108.537.2 708.533
70E.4r0.1.5 & 6 708.1 7011.55.1
708.1r3 7013.521
Pa2 PlIft 2
lable 4A2 (No 35) I10.2(xiii)
side
enclosures nlultiple pendants pendant luminaires, suitability lbr'
of
nte
ol'
644.4.202 Scc 644
Charlgeo!er time.ree Jifetv tervircs general, ofinstallation Parl 3 Charactel islics, 1ir)re/cu[en1, 432.4 ovcrcrulent deviccs Ch aracter islic s.
Appx 3
Char!ing installatiolN, electlic vehicle tee Elechic |ehicle Charts .rcc -l)i.E/zr,r.!
CireDratograph irstallatioDs
Appx 2 lterr 1(iv)
Cilcuit, dcfiritiol Cilcuit arrangelllcnts - division ofinstallation
Pait 2
-
Sec 31,1
Appx l5
household and siurilar plemiscs
Clrcuit-brcaker'-
-
Parl 2
defiuiti,.rn linked -
Pa2
- dcfinitiol - i eanhod neutl.al
132.11.2
Crlcuit-breakels as laull protection
1|.4.202 ,11
-
1 .8.3 Sec 432
brcakrng capacity
434.5.1 4.15.1
-
Sec 536 co-or-dinarion ofseries devices elccuode $ater heateN and boilers, 554.1.2 tbr 554.1.7
-
emcrycrcy switching t'ault cul.lerlt
olf
537.3.1.4
plotcctiol by
432.1
412.1 414.5 Sec 435
-
Scc 435 536.,1.1.2
plecatllions to be taken, where or'dinoly pclson lnay operafe dcvice - ovcrload i)rotection by - rated c$uclt to be indicatcd CifcrLi! discoruection tincs .!ce Di\con ectian lines Cilcuit inpedances, fo1 automalic
533.
&
3
r.i
432.1
&
)
533.1.t
disconnection
411.4.4
4l 1 .5.3 Circuil protective conduct{rr, definjtionPalt 2 Circujt prorective coDductol, of ring
cilcuit
543.2.9 s43.7 .2.201(i)
Circuits
-
a
-
arixiiiary
416.2.4 Note 559.s.1 202
-
l
-
559.5
oletcunerrt scttinSs - co oldiDaliolrselecrivity
-
lgri.
trllt.i al prenises Ceiling heatirg syste s f.iee.rA.) Sec 751 Ett $edded hed tit g s'),s ten s ) Ceiling roses - application of 559.5.l - e\ernption fiorr Iequitenlents tbr Cattle slreds see
mass
ll/o t' k:i Cert ifi
Sec 708
- additional protection by RCD - exterlal inlluences - isolation - overcLulelrt protection, devices for - protective nreasurcs, prohibited - scope - socket-outlets - supplies - $ilillg systerr, types oI eeluipn1ent,
I-LcJriull IttstuI/Ltlio Ltle ; Mlt tol El ec tricLl
hts tul I tr
('ct'l ific
41 L3.1 .2
t(J
ree
supplies
Caravan park, deliritioll Caravan/camping park installations -
-
boDdulg
Ce iticale
72t.55.2.4
luminaires
721.55.2.5
-
l: I n1 to t eL hnia d I Si tt t tLlLt rLlt :tu icu t
Celliticalion.iritial
Sec 708 installation Capacitive electrical cnergy, dischalgc
Capacitols,
t
Ce ilicates. alLtherticity Pafi 2
of
521.9
( entral heatins slste ls- nuin
522.'7
delinition
cables
( ENELLC \e! I:uft)peo (:ol)tttIitlcc
erground
Carnpiog palk
-
522.6.201
lhrruully ilsulatcd.
abovc
103)
lli
559.5.1.201
(
'argenrcnts,
ho sehold aod sill)i1ar prcinises
Bands
T
Appx
15
Sec 557
and ll.ree
B.ittl I circuils:
)l circuits 'Class II', pr'olective collductors Bctud
in
412.2.2.4 412.2.3.2
contfol .\irc
aorr?/
aiTarli/.r
division of installatiorr rnto electrically separ rled. arrangetnent
of
3 14.1
-
,lt 3.3
-
-
41 8.3
-
final see I ttdlcitrttits isolation rrrrnrber
462.2
of S".c 314
- r;ig \ee Finul (.it(lits ring - sai'e!) services - segregation bctwecu -
-
560.7 51 5.2
separation
414.4 3t 4.2 4t 4.4 560.7.7 463. r.
of
switching of
-
III equiptrenr
- delinition
ambient temperatul.e
522.1.
-
bare. cablcs connected to bends boflding connections see Bo ding
526.4 522.8.3
-
2
Codes of Practice aplll-oVcd British Staudard Colour -
r t4.l Appx
conduckrs
53
I
7.3.3.5
Scc
5
l
i:
Sec 526 Sec 514
colo!r idertilication of exposue to
-
current-canying capacity
-
electromcchanical stresses extemal i[fluences heating identificatiorl
-
joints mechanical stresses
-
o\erhead see O|erheod parallel
52t.s.201 554.4 Sec 514 Sec 526 522.6 to 524.2
neutral. crOSS-sectional area
li
defi
rritiorr
pilr
2
applicabiliry of Regul.lio s Compatibility. clcctlontagnetic Conrpatibi liry ot cqLripnletlt
110.1.3(iv) Scc 332 311.1 5 12.1.5
Compliance rvith - Elecl ioity at Wbrk Regulations 1989. Nolc by HSE
Pretace (opp) Standards Sec5ll Concealcd cablcs in u,alls or partitions 522.6.202 to 204 Conccntlic cablc. instaliariolt 543.4.7
-
(orci((
I.sl ot'e\r
Coucrete- steel
{)1' l.t(ncc.
Apl)\
5
tel[forc!)nent.rc. S/c.,/
Condensation in rviril]g
syslerrs
522.3.1
522.3.) Condition rcport ser flrt.rric a/
( on,:l i t i ( ) n Rcpo ]. t Conditional shoft-rircuit cu ent. I ns tal I d tidl
definition
pafi
2
Conduclntg location \,u ith rcstl.i.ted pa 2 tuovemeut. dehnition Conducting locatiolls \! i1h r.slricted movement autoDatic disconneclion ol supPly 706.4ll
8
_
,
433.4 434.4
-
Corsu deiir
-
drainage
of
erection to be completed before drau ing in
-
Chap 52 526.2 522.8.4 & 5
flarne propagation r.equirements ffexib1e. prohibited as prorective
conductor
rlrc
C'oIl1iIU
_ dciini Coutinu;
522.8.3 522.8 Pafi 2 522.3.2
ContinLrr Corrrr-ol :
(01)lrol.
r
522.8.2
( oltfol. r ( onlr-ol cr
527.t.5
(irtnol .i,
543.2.3 413.3.5 543.3.6 521.6 513.2.7 521.6 527.2 543.2 &
-
collduct(
-
dc'sign.
of
-
icientilica l110tof. dc
-
sr.l
itchitrg
nlalllat
3
finrtlolgcar
522.8.10
Controls in
57)
1)
134.1.4
it
-
52'7.2
Connections. electrical general
d
Contact
lixing.iee &rppollr
- insulating. lor clectrical sepamtion - joints - naterials. British Standards - rnetallic. accessor-ics in - more thaD one circuit in - passing through floo.s and walls - protectivc coDductor fonned by - sealing - underground - watcr in -
_ lbr
protective.r?e Ptutectiye conductors
definition
I'N.
-
Appx l0
selection and erection soldercd suppod. general Condujt and conduit systems bends cables in
sup.
_ wili
es
Sec 526
530
-sE
523.',l
-
Corrbustible dust. fresencc of'.
- sa1 - sc(
Sec 522
512.1.1
Part 2
p l€
522.5 Sec 523 Appx 4
54r.5.1 Cornbined shon c ircu ll cun.eni capability. dcliniriorl Cofi bired shr,rr-citcrtit pturection.
l1
conosive or polluting substances,
Sec 514
Table 7D
Colnbincd protecti\ c ald t'unctional pulposcs - earthing arran{cntcnts fbr
Aluminiu
-
i4
Appx 7 identifi cation of llexiblc cables
(
(
4t2.2.2.4
-
553.1.5(i)
(
-
par12
-
cmergcncy s$itchrng de,viccs identi{ication olcables and
706.41t.t.1
alun;,inium.\ee
part
(
706.410.3.lo(ii)
jo6.4l
-
Clinics see Medicul locutiorts Clocks. plugs and sockerourlers fbl CNE conductor.rc,e PEN (otiductor
-
706.410.3.10(D
560.4.1 paff 2
r,l
-
706.4t 1.1.2
Conductors -
insu lation
Class
706.410.3.1o(iii)
706.1
enclostrles
influences Appx 5
sourc!'s dellnirio,l delinition
scope
'i06.413
cond ctire pdrts,- Exlra eousconduatia pdt.ts Conduclive parts in 'Class II'
r
saf'ety serviccs Class I eqLripmerlt. Class II equiptrent. Class II equipmcnt or equl\ xlent instLlation r.,.'D,,rrl,/c ol h.itn,11
ro
-
Circuses see Frzl-qrulrrrls
Classillcation ofexrer.nal
locarion
SELV and PELV requirements for circuits 706.414.4 sources for. to be outside location 706.41.1.3 Conductivc pafts ree ,_yposed-
528.1
SELV and PELV anangelllent of
electrical separation. source to be outside fixed equipmenr. supply functional earthing of equipment, protective bonding to be provided hand+eld tools, supply ro haridlanrps, supply to protection against electric shock protective measures pemitted
l:
( o-otdxta!tu - arc lault da
-
back-up
pl
-
heatjnE unit\. uold
-
ut,",. pr",..rr,
tajl\
-53.424.)ut
..t',,i"." " ' "'(
I'aft 2 ?21.i5.2 orrrr
curu".t,,.i.
"oruuu"o' ar,,,,,".,r.*..r,.li-"
('o.\(qLe,ce\olL,\rr1r)Jrnu/ a\ic\\rl
ter)l
('orr.rrur.rrr,n
)JJ.l.5rrl
.,-r
''l4i.
ro
or rrri r(egrrrariorr.
odu(r\
R({UlJtiL)rr ('or.rrucrru, .,,. ,,,.,,r r;;;,.":'"" - rsse,,bi) rb, .",,,;;;.;;,;]':,;-. (A( Si
IrJ.i Alp\ l.
C oLrr
ji;,
-
704.512.2
704.537.2 701.53
as.enrltv ti,.
Plugr llnLl \!,rker-outlcrs
- r.!'lated Blilish - restduai cuteutStandard der,ices
7
_
dorrrestic plcrnrs(s.
t-equrrel)c
cr.r
' \:i:1,,:,':,',", Cuntrul (irL L,u.L-ttit.\) -
"
r1rrs I
B,,, n t
\?t, ul \t).4 ]^ t t,,,,_
-
cut)durtots. Itj,tru]L
-
seLltOIal nt.ea ,,f d"irrg,r, ,rrnrrg.,,r"r.,t
I
and plotcction
JL,e Ji, /1( r!,?,,j io bathruurnr ( u-L,ldltdtluo r.r,r .rAu Sc_leetr rrr r _ -
-
I
L
Palt 2
ul]erIl-uan)
I D1_.
Cul.rellb,
-
557.3.201 Table 5 t 463.3.1
s37.3.2.2 7Cr
l.j
l2.3
tot.
132.6 Sec 5221
551.5.2 Sec 31
I
313.I (ii) 543.7 Sec
53i
512.1.2
433.t.203 Appx zl
Appx 8 Sec 523
Appx 4 Pan 2 cil.uutt
Appa 4 sec 5.4 s21.2.3(i) I
haruOnt.. stal1t g
CuDdU(tot.\
of
,tf Hdt.nbtti.
( urcnt-usltg equiptrlent
-
Llet
selectiott antl erectton tri.
Lychc lc,a(ls. o\ rrloi(lprulect,on for D
Dailcs rrs.1511.772a uantd-gc. t.Ecordtnc ut.
a/ pr
331.1(v) i
-552.1.
433.3.3(iii)
_
power demand
5i2.6
I
L,t .t.L,,t\
D[iu
536.4.1.2 to .l
523.8 3 12.1
( uu (nt traD\li,,.t)tcrs, umjssior,,1 ova' L'aJ pJOtE('tturr
-
I
Appx l0
alorrg route
luraugeorents
onruli
at'(. irUll dL.tcL ltotr back-up proteclioll
clt.Lrt.r.t iltg uJpaut\
-. r aliatron
143.4
Table 55.2
641.1
434.1 523.7
P,afi 2 .163.3
r1.oss
- identificatiol ol - JIut!)r. desiglcd r(, Dl.e!ent.irnu_r - su rtchirg uli lLr nriclani"rl " DlaItlcna cc b) n)tdruDtion i,f (..L,nrr()lgcur
L
652.2.
)
",,ppo,,
- delioition - eftlctive - lleutldl ot polyphas( - ptt'allcl cr,nduct(rt.s
643.2.l
ultrue c t u t r., ge
tottoL,r u,s
- busbat trunkxtg \ystems - cablcs and uo,Idttetur.\
121.1.201
Condtturtrs tnunrLut,xlc
t,/1,
u,,,,,.,,,,
r,nled r.ahl..
536.4.201 536.4.2.2 Chap 36 Pa1"t 2
( orrtrol anLl Il.(,lcchvc]s\\ irchiDu u(\ t(c. otrltntU()n Conttol. rnoioa
;,".,
5s4.4.2(ii)
-, strroorltty ol-equ4rt)]crt
t ln
Patt 2
tcsrs
u!ll,');
542.2.3
- datur". uf - ,)rul(rii\. L,uIdLr(rr,r. htth - rirrr.d. oj hr.es anJ ur.uiuor..ol,"."
701.313
t
522.5 512.2.1
('ul-reltt - cil.culalills, prccautions to Iilnil - IlatrtrtLln r]eltanrl
701.111.3.1 7t)4.52
elck,\rr"
701.512.i
p. 1").i
.3 .2.1
704.4|.3.2
Iyl)(- spc(r1lcr1toll
Cr'Dlrul. ur
1
701.410.3.10
L-onucrurl. bar k up plutcctrun oi ( ott tutt) ui \et\ lL. - defilrriorr
Contiruity
I
e R,L r i, tg
64t.l Clros$sectional arca of oonductors and
701.1.1 704.411.4.s
Coosumer.unit - deliuirion 1,-rr
04.4
s36.4.1.4
C)iteda, rclevant
"/04.537.2
- supplics - fN-Cl-S Dor to bc used - wIll1g systenrs -
'
704.522.8.11 Sec 70zl Note 701.410.3.10
- salctr .rnd srarrJb;. - \cofr ut al)phraLi)nsupplrcs - SEL\, rnd lrF.tV cl(Llr\ - srrclcl_uutl! t utefi1ts
c(rr RCD{ erlors. :,rafic \p1i7rr,.
Coupler: (ablc.\irL, (-,
704.511.t 701.110.3.10
reduec(llut{ !t,jr.r!( \}.\trnts
536.4.1.2 536.4. t.3
ber!-\
- earthing conductors - heatiDg cabies - q inrg systenrs
704.410.i.I0 Notes
i\olarion rrl nrcoltilt; suDDJ!
betwc,(lt or crcuneDt prutective ue\ lccs nl scfies
:,;,,1:ii::i_*.-.,. - cablcs, gen!,mi - eanh electrudes
704.531.2
srclDs
Seo zt.l5
CoId opcrrtcJ swit(h(s lD bathroohe
704. t. I
LurrdJanrp:, pr_rtlu[rlr. prcler.].srl
rnalD (list|1bL]ttoI
selectiviry -
|7
plyibrtr0lr^irr|i),r,
crteDlal iltllir!,nce\
-
-
-
exelJ]pl Iocatrons
:l
lnotor stalaterlj,,idt fault cul.retrt
_ rrcrn
nteulrllrre.ri darnugr.
, -
-
Paft 2
435.2
see )04 NL,re
.,,.r,, ;jl - lil,YI,lllil,:::.,^,.,,",, .-,,...,u uc prutected !gainsr ",
433.l
ot-uleuui(al
cquipnrcrr, Jef rrion urlvr:fload and fault culre]lr
s
704.511.1
-.ur."r"uring'"iii,i j,',i"nt,srft
betu cen uunJuct,rr cDd or,erlo,,J protccttl L_ dq\ l(e
-
r
-++j 4
efsq11p61.111.
L.oJtsrluL r]on pt "..lll],:19,1,,:
-
4:2.J 5rii)
( urrrcutrr. urtrr,rror,
Pan 2 133.2.4 512.1.4 Sec 554 533.2.1
etnist:
DaDger. delinilion
Danser Ioticc,s \ee Lhu.iitjg noti.es
653.2 Part 2
I
Danger offire. particular risks Dangcrous conditions. rccording of Data transfcr circuits. prevcntion of electrical interference iu DC systerns. tlpes Defccts - additions and alterations. in e\isting irstallation. recording of - durirlg periodic- recordirg of Dcfccts or- omissions. dulirrg initial vcr-ification
Definitions Deglee ofprotection (lP) - ag cultural. hofiicr.lltural prcmises - barr'iers and elclosures -
-
general
Direct contact, protection against Jee
Sec 422
Bctsic'pi-oleclion
653.2 528.2 Note I Appx 9
-
lhult cunent clearance llnal circuits highway supplies and equiprnent reduced 1ow voltage systems
1t4.4 t t.202
705.5 t2.2
-
434.5.2 411.3.2.2 to 4 Table 41.1
4t6.2.t
Disconnector
653.2
644.1.t Pafi 2
Appx
caravan parks
708.512 708.553.1.8
insulating enclosure, barier in intermediate barier in enclosure location with lisk offlre - ELV circLrit. live pafis of
4
I
-
where cannot be achieved
t2.2.2.3
-
422.3.r(i)
hrminaires
422.3.8(ii)
switchgear
422.3.3(1i) 7
09 .5 12.2.1
.I
521.10.I 417 .3.2
saulas
703.s t2.2
special locations, other
Paft 7
swirrming poo1s. fountains
102 .4 t4.4
wiling systen]s
702.5 t2.2 521.10.1 522.3.1
.5(il)
522.4.t
-see
TT systenl
Distribution code Distributor. defi nition Distributors - cut-orLt, for isolation ofhighway powcr supply - disputes with corsumers. procedure equiprrent. suitability for additions to installation - f'alrlt curent device. protection by - not compelled to give supply in certain circuI1lstances - overload device, protection by - to bc consulted Distributor's network isolation and switching an-angenelts lbr generatirg sets
527 .2.3
Demand. t1laximrun. detemrit1ation
of Demand. Lllaxinrunr. suitability of supply for' Departulc. dcllnition Dcpartulcs froir thc RcgulatioDs
Sec
3ll
313.1(v)
Pa2 I20.3 133. r.3 133.5
651 2 653.2
Design. econonlic and reliable Design curlent. definition Dete omtion. recording oI Deterurination of prospective f'ault culrent Device lbr connecting a lulninaire
(DCL). definition Devices lbr connecting lunrinaires fixed lighting point. usc at il1 FELV systenr in reduced low voltage system not in circuit reJying on double insLrlation Devices for protcction against
-
ovcnoltage
3l
1.1
653.2
Pafi
14
2.
559.5.1(ix) 411 .7.5 411.8.5
4t2.1.2 Sec 534
Appx Diaglaurs. provision of - for safcty services - medical locatiorls Dielectric. llamrrable Iiquid
411.8.3 411.3.2.5
Documentation to bc provided for every installation Donrestic.ree Horseloldor similar Doors - in Class II enclosutes - in stleet fumifurc Double insulation
42t.t.5 422.2.3
Part2 Appx 2 sec 2 Part 2 Pafi
4l
)
1.3.2.3
4) t.3.2.4 Appx 2 sec 16 Part 2
'7
t4 .53'7
.2
.l .202
Appx 2 sec 2 r32.16
434.3(iv) Appx 2 sec 2 433.3.1(iii) 331.1
551.6
definition ofcqriipment
]l0.2(i) 311.1 Sec 314 132.
t3
4t2.2.2.3 '714.4t1.20\ Pafi 2
4t2.2. I
Double or reintbrced insulation 412.1 application of coDductive pafis. connection to protective conductor prohibited 412.2.2.4 - conductive parts not to traveNe 112 .2.2.2\t) enclosure
-
16
514.9.1 560.7.9 710.514.9.1
4i9
55r.7 the Regulations not applicable to
Diversity, may take account of Divisior of installation
-
Palt 2
Appx
-
I
Isolator -
definition Discdminatior .rce Selectivity Disputes with distributors Distribution board. defi nition Distribution circuit - definition - discon[ection time for TN system
416.2.4(ii)
709.553.1.8
-
4tr.3.2.4
-
701.414.4.5(ii) 70t.5t2.2.
I
411.3.2.1
Sec
BS EN 60529 staodard tbr
flon-sheathed cables, tru[king co1ltaining obslacle. afln's reach tionl
I
-
644.t.2
642.3(viii)(b)
mariras
I
distributioncilcuits
inspection of bathrooms. showers
-
I
-
416.2.2
-
I
Discharge lighting, firefighter's switch tbr 537.4.2 Discharge olenergy. for isolation 462.4 Discollncction times -
-
degree
-
ofprorectior -
ban iers
rvithin cnclosures
enclosures
description of protective rlleasur-e enclosurcs of equipment equipment to be Class or equivalent exposed-conductive-pa s not to be conDcctcd to protective conductor identilicatiolr olClass II cquiprnent
112.2.2.3
1t2.).2.t 4t2.t 1t2.2.) 412.2.t.t 412.2.2.4 412.2.1.1 Note
inspeL.tion
642.3(\.iii)(a)
lids or door-s in enclosures
412.2.).3
I I I
not applicablc whcre cill.lLit iDcludes a socket-oLrtlet or sinilat
devicc
1l).1.2
to ,1i2.2.2.,1 r'eir1lbl..ed irrsulatioo duriDg clection zl12.2. L3 relnovable screws or lixings not pennited 11) .).2 .2(ti) solal photovoltaic powcr supplies, '7 t2.4t2 Class ll plefered on DC side supplerDerltarJ insulation during 4t2.2.t.2 erection 412.2.4 wiring systc[1s 522.3.2 Drainage of couduit systems 560.7. r 0 Drawings for safety installatio[s Part 2 Duct. delinitiol Drtcl see Cuble ducts Drctr]i.g see Cable dLtLti g 522.4.2 Dust, presence ol protecti!e couduclors iu lclatiol1
-
Harthed concentlic wi|ing, de{iuition ( see trlso PEN unchrtot) Eanhed equipoteutial bonding and autolrutic disconrrection rge AttIott1LtIic Lliscot rc(Iion of ):fippII E;rthing iflalgenlcrts assessnlent oftypc of scicctiolr and ercction
-
-
331.1(xi) 543.1 Part 2
delinition definition
Pal.t 2
foundation rrobile or transponable unirs [etwork, deli tion
717.411.6 Part 2
resistance alLowance for corrosion
51).2.1
-
-
allowancc tbr freczing
soild[
-
TT and lT s,vstems in general
41 1.5 .111 6
-
test of where consists o1'pars- conneclion
of
-
613.1.2 511.2.8
-
ol
defirition
Paft 2
-
fot EartL fauh loop impedance - definition - extemal to installatioL to be deten'lined - for automatic discoamc-!-rio[ lbr fault protection. -seri
r-educed
lol i..:-.- .
tesling
Ea h-tiee lo.xl ;.:protectiolr b\
Eafth-tice ltcil:,
:
-
:- ,
: - :
l.)q) itltl\.i... . Ea h rnonrtn: r::-
541.7
i I i.1(iv)
-
I'[ syste
figs 9C,9L,9M
')
tesistance -
-
ptulision lor mcasurelnent of varialions ilr
542.1.2 542.2.1 512.2.4
systelt) types
142.2.1
of 512.t.201 PaIt 2 542.4
plovision of ]rl(r'c tha[ ore souce ()1'energy 5t?. i .5
Economic desigr ol installation Fltlicieircy ree Erergl ef'cieac1, Electric l'e ce ilstallations, the Regulatio s not applicable to
ll1.4 -fl 1.5 .\ppri i 6.ri.7.3
3tl.l I10.2(xii) 705.1 Notc
Electlic shock - ourent ree,.t o.t
- deliDilion
6{i_7.3
ct re t, delinition P^tt2
e:nergency switchlug
olf f. tll p|otcclion
Pad 2 465.2
I
in case oflaul1.tcs irl nomral seNicc ree Bdric
-tl8_l
protcction against
:
satety serviccs Electric sult'ace heating systems
:
Chap 4l 560.7.6 Sec 753
Llcctric tlactioll equipnlcnt rcd
-
,-'-
1t1.4.2 411.5.r
iurpedance
-
-.
cttt url,rr ,:. Earth loof in-,f.,., .-
high protcclive coDductor currents
4l r.rJ.l
fillqe
No]1-tt)lklttL:.:Earth lcakagc' r-.::'-:
411.'/.)
4l t .3.I.l 4tt.6.2
tornrinal, marin - connectiorl to Eanh - clefinition
Pan 2
Jl1.8.i
-
542..3 5 14. I 1.1
- general reqllilemeits - I'f syslems - reduced low voltage systcm - 'fN systenls - Tl syslenls
' 542.1.3.1 to 3 Part 2
definition
554.l
-
global
Earth l'ault curent adequacy of eanhins aJransements
-
Pa2
411.6.1
Parl 2
Pa2
Eafih electrodcs. seloction
-
conductor', defillition conductoN. electrode boilcrs conductor's, selection and election cor1ncctiorN, wamillg roticc at
542.1.3.1 valuo o1 - neutral point or nlidpoint ofreduced 2111.8.4.2 low voltage source Deulral ofsLrppiy fiec./lro l'E-N 554.1.5 to 7 - prohibitecl. iu earth-fiee local 41823 bonded location - prohibited, in llon-couducting 418.1.3 location
arca, definilion re(, Resiltance
de{inition
r.l
-
ing and
area
-
542.
543.5.1
Sec 5,12
Earth electrcde -
-
542.1.3.1
exposed-conductive-palts - IF-LV systcns
Ealth - colnections to - necessity lbr addilional - curents, high
-
suitabllity of
Sec 312 Clhap 54
oonrbircd plotcclive aid functlorlal pLLlposcs
E
-
-
Pa2
:-t:,tl
Rl,ilrxirt lt Lt(Iion equipmettl Electric \ehicle (EV). delirlition Electdc lelicle chalgirlg irstir]iations
-
applicalioll, scope of chargirlg point ouldoors, IP rating
Palt 2 Sec 722 722.1 -122.512
712.55.
.2.201
r0l
-
dedicated final circuil requircd definitions relatins to electrical scpararion. limiration on
-
enlergenc) switching external influences
722.537.4 722.512.2
failure ofconsuner's installation to comply with Appx 2 sec 2 - relatioNhip ofthe Regularions to 114.1 Electrode boilers (and electrode water
maxilllum dentand ovclcurent protectiotl
122.3tt
heaters) -
use
of
7
22.31t
722.533.101 722.410.3.5 122.5 722.55.101
TN system
722.4t|.4
&
6
722.53t.2
PEN conductor pr-ohibited in llnal cll-cutt 722.3 t2.2.1
Electrical certificatior't. depa Llres fiom Regulations to be recorded
120.3
ril.5 Electrical conncctions ret, Co
n
n( I irts.
al &1 ]'i(
u
I
Electrical e.llipnlent. dcfi nitiorl Electr-ical equipructrt.\r e Eq u ipttl e Elecn ical EquipDtenl ( Safity) RegulatioDs 2016 ElectricaL installation. dehuition Elcctrical Installation Cefi iticarc,
-
authenticily of
-
fomr
Paft 2 t
I Pat
2
irl
ol issue of
Appx 6
schcdules to acconlpany
644.3
inspectiou scll!'dulc recording ofdefects. ctc rcquirernent lb.
, -
skillcd persorl(s) to sigr
lbnn of
schedules to accol]]pany
Electrical illtefelcncc Elect cal s.paration. prote.lior by
644.t
644.5 653.5
Appx 6 Appx 6 653.2 653.
r
653.2 653.5 528.2 Sec 413 ,118.3
application of basic protectiorl
4r3.1
botding olcqtLiprrent
t3.2 418.3.4
disconncction rvhcre two t'aults occur exposed rnctalwork of circuit
,l18.3.7 413.3.6
4
zl l
8.3.4
flexible cables tbr
413.3.4 418.3.6
fbl onc item ofcquipntcnt
,113.1.2
for several itelns olequiplnent
413. I.3
4l 8.3 plotective conductols tbr separ-ation of circLlit
4 18.3.6
41,3.3.2
socket-oullets tbr
418.3.5
supplies for
4t3.3.2
testing of voltagc limitation
643.4.3 413.3.2
wiring systcms for 4 t3.3.5 Electricitv at Work Resulations lgSg applicable to places oflvork activity Appx 2 Itern l(iii) conlpliarce of installatiotis with Note by HSE lurthcr guidance on Appx 2 sec ,1
- 184--
Part 2
sclection and erection of Electrodynatnic effects s"e E I ectronrccha n icct l ; EI ectrcmagfl etic Electrodynamic effects on protective
554.1
coDductols
543.3.I
Electrolysis. prccautions against - earthing alaangefients - marinas. waming to users - wiring system rnetalwork Electromagnetic compatibility - equipment - immunity lcvels of equipment Electromagnetic Compatibility Regulations 2016
542.1.3.2
Fig 709.3 522.s.2 Sec 332
515.2
Appx 2 sec
leasures against -
Appx 2 sec 8
644.4.202
-
definition
I
13
Electronagrctic distl'llbances,
departures fiom Rcgulations.r?e E I ?(. I t it'u I krt ill('Ln
Electlical lnstallation CoDditron Rcport - antherlticity ol'
Appx 2 Item l(i)
-
7)2.413.t.2
protective lreasures not perlnitted RCDs selection and erection sockeFoutlets tbr
-
Electricity Safery, Quality ard Continuity Regulations -
Part 2 EV
-
bonding networks cable segregation / sepamtion catlhing and equipotential bonding
444.5
EMI. measurcs to reduce 444.1.2 power supplies, multiple source TN
Tl
or earthiDg of scope segrcgation of circuits sources ofdisturbance TN system TT system Electromagnetic effects in cables Electromagnct jc inteference, [Ieasutes to reduce Electrornechanical stresses condLlctor and cables
-
Sec 444 Annex ,4444 4444.1 to 3 4444.4
444.4.6
444.t 444.6 444.4.t 444.4.3 444.4.4 521.5 332.2
-
521.5.201
eafihing arangements Electronic devices f.!ee a/so
542.1.3.1(ii)
Semicotdudor det)ices) - as safety source for SELV or PELV systems Embedded heating systems -
-
414.3(iv) Sec 753
additional prctection by RCD application, scope of automatic disconnection by RCD bums. plotection against documentation to be provided electrical separation. not for wall heating systems heating cables
heating-fiec areas, identification
753.415.t '753.t '7
53.423 753.514.1
153.413
of
Sec 753 '753.412 '7
-
mesh metallic
g
53.4t L3.2
7
7
d
7 7
overheating. protection against prevertion of hamful influences protection by double insulation protective measures not permitted
53.520.4 53.522.4.3
53.41t.3.2 53.424.102
753.424 '7
53.515.t
753.4t2 753.410.3
user infomlation Emergency control, fundamental
principle
132.9
Emergency lighting - segregation fi-om otlrer circuits
-
standards
lot
supplics for
110.1.3(ii) 528.I Note 2 560.9 Chap 35 Chap 56
I
Energcncy slopping -
-
Pafi 2
deii itioil
f'unctional testirg of Emcrgercy switchrng otT
-
643. r 0 -
Dachincs plug and sockct-otidel not to be plovided for provisiotl ot' selectiorl
ofdc!ir'cs fbr
E11closurc, deliniritll1
Elclosutcs -
-
acccssibilitl to equiplllent withi[ 1br corlsurl)er rlnit ill doDlcstic
prenrises tarjoiDts and tctnlinatiolls plotective coDduclor's lbrrned by EnclosLLres, pl'otection bY -
-
- arc-resisunl. lor llxcd equiplnent - Class ll ot equiralefi - degleas ofProleclil)i - fire-r-csistant. lor tixed equipnrent - ilspecdon ol - lids or cloorr iu -
openings
rrl
sccuritlg
-
ilsulation of
53r.3.1.3
detirition
Pafi 2
418.t.6
-
i11non conductiDg location outdooN, Protectior bY RCD
-
oil-fillecl
Sec
lll
Pafl
5
-
stationaly, dcfinition suitability ibr power detlland/d[Lty
Pa2
526.5
-
surl'ace tc
421.1 3(i) 412.).2
-
I
42r.1.201
116 2
&
1
2
'121.1.2(i)
6a2.3(viii)(b) 412 2 2 3 t4.4 .201
|
'7
416.2 4
APPX L7
tcmrs
delaiied reconnnendations scope ofrecomnlLlrdations lor Environutltal conditions. funda ental PrinciPle /!?e a/so
-
Eternal
inflienccst
EquipneDl - accessibility
Paft 2
Appx 17, ltcurs 17.2 Io 17.13 Appx 17.ltenr 17 1
l]2.12 Sec 5l
l
testiDg
'
-
additional proteclioll agricultural prcnliscs bathtoollls
-
slippleme lrrary, sizirg
-
-
swinrtrirg
Fscapo
6'13.10 Sec 133 423.1 417.3.1
'111.1.2(iii) 552 1'2
6112
r
'
)
643.2.1(i)
ol.rte (eMelgency)
P'fi
5
I 10.2(x)
_
in
4)2.2.1 Paft 2
EuroDcan
422.2.1
systelns
521.10.202 Note I
(lunmitec lbr
Electl'otetlrrrical Stirndlt'dizcti,rn
""i..iii.r,'"
ti|i'5,* ,'
EY see Eleclric vehicla Exciter circuits of rnacltil1cs, omission 431.3.3(j) ofoverload protection 110.2 ExcitisioN lionr Rcgulalions
Fxhibition. del'Luition F-xhibilions. slows and sta[ds -
-
-
accessiblc strLlcfuml parts.
tnaiI
boMirg of addilioral protcctior
bY
RCD
emergency switching hcat, guarding ofequipmert
ptoducitg rnsDec!loll
ar'l turllllA- dlt(r (aell
,i'..nrhlr
Sec 464 53 7.3.2 560.6.2
l-4
'7-O2-415
t02.55.i
cable malugclDelrt systenls
wirirg
Chap 46 Sec 5i7
rncelrrn,...
1 2
switchgear and controlgear located 422.2.2 in
515.2
Tables4l.2to4
4l8
- dellnition
Sec 312
1
in
pools
tcsring
Paft 2
Part 2 411.3.2.1
714.4113 L2
41 1'3'
of ofequiPnent Escalators. exclusion
-
-
Soulaa.:
418.2 4 r r.3.1.2
sal'ety sepa|ated circuits.
-'
- defirlirion - disco tection tim6 ibt - earth faulr loop tmpedances tbr - Ructional testing of - fundanrental requrrements - guar-ding, agailsr bums - lraving bare lire Pans - heat dissipation - incotporatrng motors - inspectior ol - isolatiol and ss itchrng of
I
llghtr g rrlsllllatiollJ. nrcrallic str'uctt[(s need not b(
5 12.1.5 .121.1.5
cnvironmental conditions- ixposed ll:.5 to PaIl 5 erection ot' fixed - accessibility for mailrenance 513
Sec 544 541.2 Part 2
ol
Dlailr oLrtduur
containilg flamrnabl. liquid cul.rerlt-usirg. dcfinilion
Part 2 Scc 554
I
earth-ftee locai
412.2.1.1
compatibility of
I
4l 1.3.1.2
delinilioll
Class
-
705.415.2.1 701.415.2 721.111 .3.1.2
conductols _ - rnain - sclection ar1d ereclitln of
Lrectiot
-
412 2.1.)
type-tested
1
cu1lc[t-using. rcquirenlenls electical, definition elecfiomagnelic cornPalibilit] of
Sec 702 Part 6
of
EqLlipoteDtial bond111g f-!c.'.r/so B ot tl i t tg; St4tplencn tu r.t' equipote lidl bo Llit|g)
applicabilit) of the Regulalions to
ll
423.1
sni:nming pools
-
11.1
I
t33.2.1 42t.1.2
Pelalue of
bonded - proteoti\c
132.5.1
I
512.1.4
416.2.3
-
421.1.5
selectioi of
i13
I
4r r .1.3(ii)
5I2.I
of
tlelluitions and rclated
416. l
operaliollal conditions pottable see ntr;/rlle
465.1 537.3.3 Part 2
of
Encrgy dliciencl
443.6.2 Table 443.2
-
Energy. discharge ofsloled slgclljq6l '16? 4
-
ol
mobile -
537.3.3.1Note
116')-l
removal ol operring
iilpulse carcgory
Pa2
definition
-
-
-
isolariorr. tbr each separate strLlctule
anddishib$tioucircuit
Paft 2 Sec
7l l
'7|.411.3.1.2 711.411.1.3
7l L559.4.4.3 T
|.422.4.2
-ll.o 711.537'23
535
-
lampholders. insulatiorl piercing. onlv noD-remolable allo\\ ed lighting installations motols. isolation of scope of rcquirenlents SELV or PELV sho\\,.
dcfinitiorl
socket-outlets. stand-
ffoor
711.559
ounted
delinirion
crhi - I at
7l
P rcte
l.l
'711.4t4.4.5
'71t.4tt.4
-
I a\r.
-
I
atr
S?pdt'1 t ed
exh d-lo\r \Dltage) application
4|.7.1 4t4.t
delinition
Paft 2
ExtraneoLrs-conductivL'-pa
7tl.l |.4t0.3.4
Po tent ia I h,
s
-
,115.2 - additional protection - agricultuml premises 705.415.2.1 - autofiatic disconnection ofsupply Sec ,111 - bathr-oonrs 71l.4l5-2 - bonding ol 411.3.1.2
415.2
exp los i \:e a I ntosp heres
Exposed conductive-pafi. defirition Exposcd-conductive-parts - additjonal pr otection agricLrltural and hor-ticultLn al ptemrses
Part 2 415.2 705.415.2.1
automatic disconnectioll in case
of 4t t.3.2
laLrlt
lrorerllcllt
-
systcms
4t],.6.2 4t r.6.5
prolecti\c caltl'iillg reduced lo\\, voluge systens TN systcrrs
ll
41 1.3.1
4
systems
construction sites earth-t'r'ee local bonded location elecl cal scparation embcddcd heating systerrs. provision to bc made on site
exenlptions fiom fault protection flinctional extra-low voltage systems
-
-
ofequipl[cnt- not
-
as protcctive conductor placing out ofreach protective conductorc fotmed by SELV or PELV circuits
-
slatic couvertors, on load side swin'iming pools ExteNioDS .\ee Additions to instaliations
-
l
of
-
eqlripment to bc suitable for outdoor lightiDg. street lirfllitutc
rot
be bonded
706..110.3.l0
418.1
'714.411.3.1.). 417 .3.
543.2.1(vii) 543.2.6
swinming pools
702.1ts.2.
F
4tI.5.I 7
04 .4 t L3
.2.r
4t8.2 4t3.3.6
structures. etc amusemenl device.
4l 8.3
-
153.411 .3.2
-
bonding wherc livestock booth. definition buried cables. protection and
-
calavans. PME prohibited dodgems. electric. voltage to be
-
cquiprnent, IP protection linal circuits. RCD protection of nle. protection against genemtoN inspectioll and testing after each
-
isolation required for cvcry installation IT system. not where altemative joints in cables lampholders. irsulation piercing, oDly non-removable allowed lighting installations
4
r0.3.g(iiD
543.7.1.203(v) 4t 5.2 717.52.1
418.1.2 418.1.4
417.3.1
543.3.5 414.1.1 414.4.4
551.4.3.3.I 702.4t5.2
542.1.3.
deinition
automatic disconnection of supply
,rarking
ELV
asserrrbly
543.3.5
-
Sec 740 Part 2
740.4r0.3 740.11I 140.415.2.l Paft 2 740.521.1
140.4tt.4 740.55.9 740.512.2
740.415.I 740.55.1.5 740.551.8 740.6 '7
40.537
740.1t1.6 7 40.526 740.55. r.2
740.55.l
lumiraires 740.55. L luninous tubes and sigDs 740.55.3 placing out ofreach. acceptable for
dodgems
5t2.2 '114.512.2
scope o1'requirements shooting galleries, laDrps to be
pr'otectcd
1
740.410.3.5
public supply, diffetent sources not lo be inlercollrlccti:d 740.1
r(iii)
)
4t8.1.7
Fairglound. deflnition Paft 2 Failgrounds- amusement palks and circuses, telnporary installations for
Extemal infl uence, definition Pan2 Extemal influences - classification of Appx 5 - ea hing alran,sen'lellts to be suitable
for
418.2 418.3.4
.8.3 411.4.2
41t.7.3
bigh protective conductor cu(ent equipmcnt local boilding of mobiic or transpo able units. pt ecautions against energizing non-conducting location
-
.
if
r1eccssary
-
121.4tt.3.t.2
conducting locations with rcstricted movernent- PELV circuits in earth-free local bonded location electrical separation ir non-conducting locations outdoor lighting, metallic shrctures placiug out ofreach propagatillg potential outside nonconducting Iocation protective conductors fomled by
706.41
connection, for earthing and automatic discouDection -
l
camvans
need
conductillg locations with restricted
l
Sec 414
i n s td I I o / i ons - extft !- lot\ \,o I ta ge Extra[eous-conductive-pafi, def,nition Pa.t 2
711.52 "^ee
er t n
insiallatiors.\ee Zlgrrll€
711.5t
7
: lt' u n c t i o nlt I et t ro
cti'e
provided by SELV or PELV Extr-a-low voltage lighting
711.313
wiring systems for
-
Parl2
switchgear a1ld controlgeal, access 1rl only by key or tool tempomry installations. requirerrents applicablc to temporary structures, supply cablc to. RCD protection requiled at orlgrn
sclection and erection ofeqtiprnent in relatiol'i to Sec 522 ExtraJorv voltagc /see ulro L|-)lxlge.
711.55.4.r
Part 2 111 .55.1
supplies supplv. TN-C'S prohibited
Explosive atmospheres
-
71 1.5 59.4.3
l3.l
740.r.1
740.5i.1.3
-
socket-oLltlets supply to t.nrpomry irstallation. RC'D protcctiorl switchgeiir und corrlrolgL'ar, access oDly by key or lool
740.55.1 740.410.3 740.51
740.5)
wil'ing svstenrs Fault. dclinitiou
Part
prospective /rcr a/lro P7o\'P(r( lAu I I
(:
,iIr)t'I1
-
ui't t,]t I )'. ( ! t:c it't
itit
a1tt
-
tll.
434.1 Sec 410 Scc 434
-
4)4.4
ronLluctors in palallcl dcvieos
lir
-
-
addilionalprotectiur
-
aLrtonratic
disconrtectiol in case of 4l r. r (ii) 4l 1.3.2
definition
Part 2
doublc or r-eil1f-orced ilrsulation
4
elec1,'icalsepal.ation
4
t2.2 t _l.l
4r 1.7.3
plinciple gcncrating sL'ts. \!hcrc instalialjon t'urdal11enlirl
includes
-
-
5s
Chap 64
equiPrncnt reduced lo\r rcltage s)stcnls
410.3.9
special neasrn'es Faulla, hazard Io wiring system Feedbaok. D(' FELY tee l-undiondl ertftrlorr
Ferronugnetic cnclosures Filters. prescnce of Final circuit, detiri(ior1 Firul circuits '
521.5.
Firc extinguishilg dcvices, orrission of orerload protectiorl in cirouits supplying Fire, protection againsl - agriculiural iDstallatiors
-
applicability ol Regulaiions to circuits fbr sataty services
-
equiplneut enclosurc constrLlcted duriug eleotiol cquipnlcnr, li\ed exhibitions fir'e hazatcl to ad.jacent matelials
-
5
5
1
.4..t .1 .2
Part
:
corltlol of
31,1.1
discolrnection tjrnes. for car'thing aod autonalic discomection .\de
r3r.r(ii) 560.7.2 421.1.201 Sec 532
42t.1.5
liquid
42t.1.6 421.1.2 to 4 711.422
42t. ). .t 42t.1.2
lirc hazard to lixed object or' 42t.1.4 building clernent llre-resislart scrccning ot enclosure 42.t.t.2 421.1.6
-
heating coDductors and cables sLl ace telnpcrfl lure of equipnrcllt
thelnlal ladiation \\ hcre particular-risks Firefighler's slvitch - provision ol
52'7.1
421.1.2(iiD 554.4 42).1.2 420.1(i) Sec 422
537.4.2
-
rcquirernents Firelightrng systetus. cables fbr serccns or cllclosures fo1
531 .4
560.
cqurlnent 421.1.2 42t .t.3
421.t.201 421.1.6
31,1.3 31,1.3
Appx l5
iigh prutcctive conductor
4-
705.122
F'irc-l'csisunt'
-
current ring -
Sec 527
ccluip rent coDtaining fliuntnablc
fire-segregatedcorllpa meul. prccautiolrs within hcal dissipalioD of eqLLiplncnt
Disconue(Iid1 titttcs
-
dcliccs for
433.3.3(iv)
421.l.201
I
Sec 314 314.4
earth fault loop impedances see Eart lt JLur I t kxtp itnpeda nt e Durnber of poil'Its supplied by number requircd radial a[angenents lbr household and siIr1ilar prenrises to supply ccluiprrrent producing
consunrer units. dolnestic
560.5.1 560.5.2 560.8.1
42t.t.3
522. r0.1 331. J(ix)
allallgc1lrerlt ot, gcnera] connection to sepamtc \!ays
-
saf'cty selvices lbt
41 1.8.3
410.1 of rcquiremcnls 114.2 SELV oI PELV s)stenls single l'ault conditions, provided lbr Sec 410 Pan 7 special locations
-
52'7.1
642.1(vii)
t ..1
inspcction and testing oniissioll oltbr ceflairr ilenls of
Sec 418
-
53't .4.2.2
Firc baniers
131.2.2
scoPe
-
of
t 4l I.1.3
|.52)
528.1Note 2 Chap 56
434.2 Ii
l10.1.3(v)
560.10
tbr
supplies fbr
llrclighter's switcll
linclional extra-lo\\ \ohagr'
-
314.2 314.4
lioln olher cilcuits
Fle corrdititlns,
l'ault
-
ol
7
segregation standarcl
543.2.9
543.7 .2.2011t)
scpar-atc contr'ol scpar-ation of
Fire a[thority, locdl. sitir]g
Scc 415
-
-
432.1
432.3 Sec 415
omission ofde!iccs lor position olrlevices for Fault protection /re. .t I to,4 utotnu di.tLlrtne(tit)tt r)/ tuppl-\') -
+il.l.to.r
systeir'l
.l so P t'o spe c I i |e
tc]1tl
protection agairtst
Pari
ovelload proteclion ol prolective conductor of to srpply elluiprrlrJnt pl'oduciltg high proteclive condlrctor
Fire alaul syslelns - cables 1br exhibitions whete no
Pafi 2
l
deiinilion
cu1'rent
-
2
IarLlt cuffent frd? .r1vt Shott tircuit dL'lilii1ion
-
541.7.2.201(ii) 4.11.r.204
auargements fbr household and siurilar premises
Appx
contilluil) t.sl
643.2.I
structurll elelncnts, cablcs passil1g 527.2 tlllouglr, sealirg alound Iixed equiprrsrt /rec dlso Equiplllent, /txetll -
-
tlclilitrort
Part 2
hcat di!sipation
421.1.2(iii)
Firlng ol luninaircs Flamurable licprrd, in eqtriptrent f lexiblc cable. cletinitiol
559.5.2 421.1.5
Pan2
15
537
553.1.3 Fused plugs Ftses (see also Oven:mtcl1t proleclive
Flexible cables sc'c' Cutbles. llerible Flexible conduits. ptohibitcd as
collductolS
543.2.3
nr-oteclive heating systenrs fsee d/so Embeddcd heatirg systems./ Floor-wannirg cable FlooN cables passittg thtor.rgh cables under conducti\c. in eafihJiec bonded
Iloor
Sec 753
554.4.4
-
527.2.t 522.6.201
4t8.2.4 4l 8.1.5
location
- irsulating. r'esistance ol - $irirg systefi btlricd in Flora. hazard to wiring sYstenr Fluct ating loads J.c a).ttlit louds Forced air heating systelns Foreign Standalds Foundation cafih elcctfodes Fountains i/tee d1s.r Srtinnning pools) - equipment. mechanical protectiorl
522.8.1 522.9 424.1
5
542.2.3
luminaires in zones protective measures scope
ofleqlire
ents relatillg to
702.32 Fig 702.4
-
702.32(iii)
zone 2 not applicable FleqLlcrcy -
o[ culTclt-canling capacity
-
supply. assessolenl of FLinctional bondlDg conductol.
Appx 4 sec 5.3 331.1(x) Sec 652
5l2.l.l 313.r(ii)
definition
Part 2
equipment with high protectivc conductor cuLrents protectivc earthing in relation to
5,13.7
542.1.1
s43.5.l
Funciional extra-low voltage FELV. Pafi 2 definition Functional cxtra-lo\\ voitage systel1N 4|.7.l - application ol 4lL.7.2 - basic protection i'or 4tt.7.3 - exposed-condtlctive-Pafis ol 411.7.5 - plugs. socket-oLltlets. etc. of 4|.'7 .3 - p mary circLlit of 4l L7.4 Note 411.3.3 - RCD not required 4tt.'7 .4 soulces for
-
iestiDg Fr.mctional srvitching -
643.3.2
-
Paft 2
definition plovision of sclectiot] ofdcvices tbr
463. r 53 7.3. I
Table 537.4
Chap
Fundarncntal ptirciples Fuse. dellnitiol] Fuse calrier. deinitioll Fuse element. dcfi nition Fuse elements. fbr selri-el1closcd fuscs Fuse lirk. dellnition Fuse links -
-
marking ofintendcd type non-intelchangcabilrtl ol r'cplaccable
bl oldinan
-
person
533.1.2.2(i) s33.1.2.2(ii) 432.t 533.) t32.14.2 533.1
.l
533.1to
3
533.1.2.3
433.t.202
overload protection bY shock ptotection by
41t.4.20t 4t1.4.203 t32.14.1 533.1.2.2(ii)
G Gangways see Opercting a t11oi tenalnce ga guaYs Gas installation pipe,
Gas meters Gas pipes main bonding
d
definition
Pa2 544.1.2
ofserice
4 t|
.3.t.2
544.t.2 542.2.6 prohibited as earth electrode - prohibited as protective conductor 543.2.3 General chamcteristics of installation, assess1nent
FunclioDal cafthitg -
-
semi-enclosed elements for
533.1.2.2 533.1.2.3 432.3 533.3 Table 537.4 553.1.3
of
Part 3
Generating sets f.!ee 4lso Standby Sec 551 sltpplies) - altemative to distributor's network, 551.6 additional requirements - disconnection to prevent danger or
Paft 2
deinition
-
prohibited in ealthed neutral rated currcnt to be indicated selection of
single-pole. in line only Fusing factor
'702.522.23
ofconductors high. oscillations ofperiodic inspeclion and testing sLritability ofeqLripl11ent lbr
-
0).4 10 .3 .4.2 102.1|
zones
-
functional switching. not for in plugs marking of non-irterchangeability of links overload and fault protection bY overload protection bY
-
wiring. additional rcquire]nents
etTect
-
cartridge typc, prefered fault protcction by
702.55.3 702.55.3 7
-
accessible to ordinary Persons
-Scc 102
of
-
.l
-
13
Part 2 Part 2
Pafi 2 533.1.2.3
Pafi 2 531.1.2.2(i) 533 1.2.2(ii)
5l l. L2.2
-
damage
551.2.3
551.4.3.2.1 eafthing arangements for extra-low voltage - self-contained equipment, section 551.1 not applicable to
-
systelns
551.3 551.4 551.2
-
fault plotection general requirements harmonjc curents. circulating, effects to be lir1lited
551 .5.2
-
isolation of overcuncnt protectioll parallei operation -
551.7.6 551.5
-
551.6.1 551.7 5 51.5.2 551.4.4 551.1.1
-
Precautions to Ptevent
with distributor's network
\!ith other generator(s) ponab]e or movable poweL sources lor scope static conveftorc" installations
incorporating stationary batteries, installations incorporating Global earthing system Glossdry s ee Defi t1i t io n s Good workmanship, fundamental princiPle Cround-recessed luminaires Guarding of equipment. against bums
551.1
551.4.3.3
-
551.8 442.2.1
Part 2
l34.l.l 559. t 0 123.1
H
I
Harrnonic eurrents cornf atibilll), ol c!]rLjpulcnt due to gcur'r-atirtr set etl'cc! of. iI billanccd three phase
Chap 33 551.5.2
Appx 4 secs 5.5, 5.6 neutralcorrductors
43).2.3 523.6.1 523.6.3 524.2.2
-
overload dc|ices. s..lection to take
-
plecaulionr
accoun101' 1()
limit
1 plen. sjzc ol'neulml tbr
Hannonic distor-riorr HanironiratriJn IJoctLlIe,tts Flanlolization. r oltagc Hamronized cablc eore colouls
due
-
551.7.3 Prefacc Appx 2 sec
421.1.2(iii) 554.i to 3
-
switehgeal, oper'artion of renlote
IndirccI contacr. prolcction agaiust ree
462.4
of
Appx 2 ltem l(vii)
['a(
Pa
2 2
132.
I[lbrmation technology. circuits for .,/
1t4.r 1r4.531 111.531.2.t.202
Part 2
t32.3
I10.1.1(xxvii)
supply t-or
Seo 730
lnlet, caravan lnspeclion l.!ed ah.)
-
'72t.55.1 fe r itic
ct
tb
n.
accessibility tbr
132.12(ii) Sec 513
-
detinition
Pafi 2 711.6 710.6 612.3 131.2.t
cxhibitions 1'airgr
oulds
iritial, checklist illitial, requircmenl ti)r
114.41t .202
553. 1.3
Sec 515
)
Ho[seboar ri]c rtrl./ri,,.rr dcilnition t{ousehold r.rr simial installations -
t t
of lndustr'ial plugs irnd socket-outlets Inllucncc. Dlutual detlinental.
lliland na\ igatiol vcssels. onshore
554.1.,1
5l4.l.l
Appx 4(6)
dlop
Pa2 .2(ii
1 L I 537.2.1 517.3.2.1 418.2.5 418.3
lndLLctive electrical e11etgy. discharye
Ingress ploteclrol -!cc Dagr?e
0. r
.1).2
5 1,1.
311.1(x)
111.514.t2.20t
t r
537
l-uult proletlio]) hductance, ellecl on cable voltage
pr-cvcntiorr 543.7 543.7. 1.205
notices- exernplioD lionr protection against electric sllock tcmporary supplies Hoist t\,c11. oabl,is irr Hor-ticnltural plemises rc,e, A gr ic I r ra I pret t r ; e:; Hospitalt ke lvlc.l ic-d I I a( Ltt i ol/s
-
Table 443.2
rrechanical rrainterrance switclring restricted areas, wara.ing notices
Il4.t
-
ilppli!'atiou of secrior) discolucctiolr time rsolation and switching isolatiolr bv distribulor"s cut-ou1. approval lccdcd
e
Impulse voitage, rating l dicators -
' -
4I0
Highway. clelinitiun Part 2 Highway distribution board. dcfinition Pat.t 2 Ilighway distr:ibruion circuit.
floltiutc )
.4.4
Appx 2
Sec
]l
Sttaet
t
533. r .2.2(i)
Sec 751
tliglrway porier supply. definiliorl Higlllvay po$,cr sr.Lpplics /sce alro
).
533.1.3
agricultural prcrrises 105.422.6 bathlooms, for water 701.55(x) whcrc ir)rr-cns.d lilc r isk. to bc fixcd 422.1.203 Hcaiing ooridLlclors and cables s54.4
deliDitior
i n t pedtu tc
4
lirelighter's switcll fuse link, type of isolatiol devices, operation oI
-
Higll voltdge rlecuode \rater heatels and boilels High r'oltagc ltuninours tubc signs. liccrNilg eorditions
cilcuit. for autonlatic drsconnection eardl tault loop rse Earth liult lrxtp
cir'crLit-blcakcr ovcrcur'l-er1t sdtir]gs
Hcaldrcarc ccntlcs :ee L\leditttl
inlonnation to be plor ided High flequency oscillations LIigh voltago kc li)ltLE(. tit)tninol
-
-
Parl 2
Patr2
-
52).6
tr.r
-. eaftlring.r.e tarlilng l5
7
Hazardous lrr e pan. dcfinJtion llazardous-live'pafls not 10 be accessiblc. turdaurmtal r-uie Healrh and Salely aI \!brk ctc. Act 197 4
High pioleclive conduclor cLlneDts - ear'!lling requircnrcnts
ldentificarion (\ee LtIso Noticcs) colour see (i)/oul' protective devices 514.8 IEC see htterndtitrlall ElectrcteL'ltnic.'l
-
Llpedauce
l l3.l (,
Hanronizcd Srandald. delinition
Heat dissipatron oi equiprleut Heatcrs t-or $atcr- elc. Heating :rppliauccs '
462.1.20t 553 r 20r
lrrrrleNiorr healers re? llater ltettters lrnpacl. darnage to wir-iirg systenrs
333.2.2 551.5.2
Appx
swltcli lb. socket-o tlets lb1, seleclion
1r]afu
6,11.
-
periodic altemative ar]'angeulelts - asscssmeni tbr maintainability - calavalls conditio[ teport
1t4.4tt 114.5t4.t2.202
examples, hst of
528.3.5
lieque cy ol'
iNpectiol
I
I
Chap 65
341.r Fig 721
Sec 651 Appx 6 items Appx 6 Sec 652
inspcction schedule lbr donestic etc plerDises
t
notice on
circuit arrangel)rellts
App\ l5
consunter' ulil, elclosur-e r-cquirclnent lunlinail'es !o bc R('D protected
,11l.1.201
Inspection aDd testiDg
I I .3.,1
5t1.t2.t
1econnlreodatiolr 1or, t'undamental
principle - requircltent lbl skilled pcrson(s), by
I
Appx 6 I
135.1
65r.1 Part 6
65
t.J
Appx 6
53S
Isolatiou
lnslallatio[ -
-
circuit afangements
132.3 Sec 314
-
ea ling anangcments
542.t.3
elecr cal, delinitior
Part 2
-
Pafi 2
-
134.1.1
410.3.6 Sec 418 560.6.3 560.7.5
safety seNices
Insulatiorl - applied during erection
-
co-ordination. deflnitioll
Pafi 2
definitiou double. definition
Part 2 Pafi 2 Sec 412
526.1
-
distibutor's cut-out
Pa2
i
-
off-load, securing against unwanted or uniDtentional opening selcction ofdevicc as sclniconduclor deviccs nol to be
as
autot.ansfonler'. step-up prohibited 555 1.2 to Eafih 5'12.1 2.3
-
SELV and PELV circuits supplenrcntary- applied during
13
.ie.t,on
412 2.1
supplementary, thermal. cables
Pafi 2
-
411.6.1 ,111.6.1
542.r.1.1(i)
-
APP\ q t ils qC'eL ql\4 4l l 6' l to 5 exposed-conductive-parts i11 740411-6 altemative not u'here fairgrounds, 411.6.1 to 4 lirst tault in
-
insulation ofequiprnent in insulation monitoting devices
on'cnqe,ir"n,. -
.2
523.9 528.2
551.6.1
416.2.4(ii)
isolation. where equipment supplied 5:17-1.2 by rnore than one circuit - sources. to prevent paralleling of 55161 International Electrotechnical Notes on Plar Comrrissiol (lEC) 511 1 APPX 4 sec I
for
5l2.l.l 411.6.1(i) ,111.6.4
532 4 Sec 518
between generating set and
ol'Prale(lion
4l L6.5
exDlanatory tlote\ otl AC and DC
Interlocking -
IP codes scc Degree
Part 2 41 1.6.1 Note I
eanhing ol live parts irl earlhing impedance
Sec 412
414.4
531.2.5
Tablc 537.4
531') 2
- connection ofinstallation - definition
Pa2
643.3 643.5
.2.l .202
531 .2.7
identificalion ofputpose
112.2.1.3
resistance" testil1g
enclosure oPenings
l
.
7 1 4 .53'7
used as
distribution of neutral in
-
-
I
IT syslem -
4t2.2.2.4
distlibutor''s network
5l4.
definition
used
conducto$
Appx
-
2'6
46l -2 ;3 7.2.8
551.,1.3.3.3
Isolator -
560.s.3 418.1 non-conducling locations 543.4.8 PEN protection by insulation of live palts 416.1 543.3.20 protective conductors
definition in lrterference. elcctrical
531
53'7.1.2
lbr mcasuing
-
462.2 537.2.7 462.1.201
537.2.2 537 .2.6
fof
wan]ing notice tequired
538.1
-
l
Tablc 517.4 plugs and socket-outlets for prevention of unintentional closure 537 .2.4 semicoDductor dcvices not to be
532.4
prctective measure resistance of floors/walls. methods
(l7
!sr.l.o
-
used
4tl.6.4
cleliritio[
132.15.201 Sec 461
- single-pole dcvices for - static convertors - lvlrere orc thal] one suPPlY,
- functional extraJow voltage circuits 41 L7.2 I34.1.4 - joints. tirndamenial principle 416. I - Iile parls 411.6.3 - morliloring. in IT systems
-
462'4
of'f-load. secuting against unwanted 537.2.5 or unintelltional opcning 46t.2 PEN conductor not to be isolated
ll
reinforced - applied during erectiol'l
537.2 Table 537.4
543.4.1
Part 2 416.1
-
Pafi2
4t2.2.1.3
basic, definition basic protection cablc. at connection to barc conductot or busbar
-
encrgy
findamental principle serreral requitemenl. fot
412.2.1.2
-
double, protective tncasurc equivalent to Class Il see Class
discharge of storcd
- generatjng sets - group ofcircuits - idertillcation oldevices for - main. at origin ofinstallation - nrultipole devices - neutral conductol
533.1.2.2
supcrvised by
705.517.2
462.1.201
- deflnition - de\ices for- selection and erection
IDStlucted perso11 (electicallY),
Instructed petso[s - fuses for operation bY - good workrnanshiP bY - measures penlissible where
ChaP 46 Sec 537
agricultural prenlises at o gin ofjnstallation
-
134.t.1 erection. good worklnanship lnstantaleous waier h eale$ see W/aler
deflnition
-
560'5
-
nrohile or uansDor_table units. pro\ i.lorr ol trcutrai distributiorl
in
overload protection shock protective devices in signals. audible and visual
3
7l - 41 I o
i
41 6.1 41 1.6.5
433.3.2 41 1.6.5
531.2.4 411 .6.4
Note I
I I
I
J
I
Jetties.ree,11Ll/'ilr./r Joints cable. accessibiliq ol cable and conductor
-
526.3 134.1.4 Sec 526 543.3.6
conduit s_!-sten1 earlhillg anrng!'1r1enls
542.4.2.
enclosure
of
526.5
pNlecti!
conductor
5,11.1.2
e
-ife crf installlltion assessn]ent uraintenance duri:rg
whL'ro pafiicrLhr risk oflire Joists. cables passing drrough Junction boxr's -
-
cilcuils telnliuaied 1n not pcrrnitlcd ilr zones 0 or I
s60.7.8 Lit'ting nlagrrets, olltission ol overload
Sec 559
.tpplication, scope of 559.I control of 559.5.1.207 domcstic, RCD protcction rcqLlired 4l 1.3.4
exhibitioru
522.6.201
102.522.24
-
FELV plohibitcd lile lisk, precautions
ol
rnirimurn
irsulating enclosures opening enelosur-cs bv
412.2.2.3
cilcuscs
L
outdoor 514.1i.1( i)
bonding conduclor connectiolls capacitor retailling ullarge nain carth tcrnrinal (shclc
514.
r
3.1(ii)
416.2.5
s1,l.ll.1(iii)
separatc)
PVjunelion boxcs
712.531.2.).5.1
7
r5.521.107 5.414
7t
715.525 71 5.52
aDd
740.55.1
rnedical locatirrns" sr.rpplics
llurking. llunting
at ealth electlode
715.530.3.104
fixcd llghtr11g pomt. colllrcclion to w inrrg systcrn 559.5.1 gcnclal rcqrLilcnrcnts 559.3 high vollago signs ootsidc scopc 559.1
702.55.4(ii)
()1'
t5.4t1 .1 .20]. 5.422.)06 7 t5.422.107 715.530.3.104 7 t
t)ilgrounds. arnrrsc[rcnt parks
4t6.2.4(i\
'715.524 7
- protective devices. locatior of - SE[.V sources, irlstallation of - susper'rded syste s - translblnieB, standard fbr - \,oltage drop. lmited to 5?; - wi ng syslenls
swimrning pools. equipnrent in zone
-
for
-
addrtiorlal prorcctiolr by RCD bonding oi nctallie structlfes not
-
distribuiol's cLll-out, approval
iLcccssrbilily
ol live
pnrts
Decessary
710.559 Scc 714 '711.411 2.201
7l,1.4ll.l.l 714.411.3.1.2
114.537.2.t.202.
require'd to use
-
bayo|et
559.5. L205 '72.t.55.2.4
- exteltal illfluenoes 114.512.2.t 114-537 - isolatioir and swilching - lloticcs, exelnptio11 liotl'r 7 r,1.5 r4.12.20r - prolection ol ecluipnrenl. lP rating 714.512.2.105 - slrope 7l,4.1 - lcnlpomry supply uni1.label 714.514.1).202 - poi t. fixed. connectio to wiring 559.5.1 - saLty, medical locations 710.560.9.1 - tenlporary lestool1, excluded 559.l(iii)
-
centre coDtact bayonet type Edisoll screw exerrptron tiour requirenrents lor cnclosures insulation piercing. to be non-
559.5. L206
wiring systenN
559.5
559.5.1.206
Liglrtl)ing prutectiorl, the Rcgulatio11s not applicable to LightninB protection systenl -
110.2(ix)
-
srvitchgcal and control_ecal 5 t,t.1.1 tcmpolaly supply unit on high\\,ay 111.514.]l2.202 Lacqucr', gcncr-ally not as insulatioD ,1i 6.I Note Lamp coDlrol circLril. suilclred neutral 463.1.2 Fig 46.I
irr
Lanrpholders - batleD, applicatiorl
-
rcurovablc typc
-
overcur-reot plotectiorl of pendallt. sr.Litabiliry f'or nlass suspcndcd temper--alure
voltage
rati[g
lirrit
Leakage cumcnt
lr.d./ l so P t'ote.l i v
559.5.
r
(iii)
,+16.2.4 Note
assesslllcnt
of
del'lnition Leakage (plotc'ctivc couductor) cumelits and lesidual cu[cnt deviccs
Licensing. prcrniscs subject to Lids in insulating crclosurcs
-
botding of
-
559.5.r.204
Light
559.5.2 559.5.1.205 559.5.1.201
41 t.3.
I
I
t.2
542.4.1(iv)
711.559.4.3 740.55.1.2
-
retelcr)ce fu staDdaad mg plotecdol zone
5,11 .3
-
corlcepl
delinition Lightnutg stlikes. direct Ltgl\ts .\ ce
(onchkttr' ('urrcnI) -
-
,^
715.52r.r06
conductor closs-scctional area,
in rclation to lirt'conductors Tablc 41.1 in telation to prorecrire conductors lables 5,1.2 to 6 Key l.\ee dl\t) Tu)l- li, ) '7 - fhirgrounds 40.5 )
-
bare corducto|s, requil enlents
-
-
Labels (vec ulso
extralor,v voltage -
71t.42.2.4.2 711.559 Sec 715
521 .8.1
-
I
433.3.1(ii)
Paotcclion
Lighting installatiots /sec.r/sr.r
K
-
560.11 52 8.3.5
422.3.5(ii)
swinmjn-c pool or' tountairl. except fbr SELV in zone l
k values
341.1
Lile salely systcrN Liit nclls, cables ir
541.3.3. l0t 541.1.6 543.3.201
-
of
Lu
t t I
i I 1 u i re
534.1 Part 2 443. t.1
,143.1.I Note I
s
Lin 331.1(vii) Purl 2
53
r.3.2
ll5.l 4r2.2.2.3
tatiorl of ovel'c urrerlt, protcction by sou.ce Lirnitations, peliodic inspectio alrd testiug, recording of LiDe sonductor. delinition Line conductoN -
-
cr-oss'sectional atea
idcmillcarior of
of
Sec 436
633.2
Pan 2 524.1
514.3
'lable 5l
541
-
number ofloadcd conductors overcunent dctection in Protectivc conductol- sizcd in relatiot'l to
43t.t 543.1.4 Table 54.7
singlc-pole deviccs
431.1.1
nuniber aDd typc L1\e pafi. definirion Lir e-par1. Haza|dous-. detiuition
Sec 312 Part 2
-
Livestock - protectjvc lreasures
I
414.1.1 4t 4.4.2 l11
silLLations for Scc 705
40.4t5.2.t 705.5) 7
-
wiring systenrs in locations lbr
Loads -
-
fluctuating.r?. a) ('/l( /o./.lt rapidly l]uctualirlg
unbalanced Local supplenrentaD, bordirg.rce BonLl i n g ; Eq u ipo trnt i t I bottcl i ng Locatio[s c'xposed to lirc r]sk. safeq/ servlces n1 Locatio1ls. speclal
331.1(iv)
range co!ered by RegLrlalions systenr. redLrced
0.r.2(i) ,111.8
(Safet],) Regulations 20 I 6
Appx 2 sec 8
Luminaire- delinition Luninaire suppotling corlPler ( t-SC).
Pafi
2
insulaiiol purpose
of
Lulninaire track svslctr l,-ee cleliltitiotl ol SoLke/-t)utlct iiPntt 2) Lunrinaircs -
-
bathrooms caravalls ceiling rose fbr colrpensation capacitors
59.5.
1(
fairgrouncls
fountains genelal requilemenls ground-lccessed eroups having conltloll ncutral for polyphase inslallations
in locations oiincreased fire risk
41t.1.5 .11
1.8.5
1t4.4.3
1t2.t.3
q42
mass susperded parts ofcable $ithio
543.2.2
643.10 412.2.1. r(iD
537.3.3.1Note 537.3.3.2
Regulations not applicable to
110.2(xi) rotating, excitcl circuits of, ornission oloverload 433.3.3(i) - rotating, selection and erection of Sec 552 Magnets, lifting, omission of overload protection 433.3.3(ii)
Main earthing temirral - connectior with Earth - definition selection and erection
of
542.1.201 Paft 2 542.4
59.5.1.203
5
59.3.,1
701.55(xi) 3
740.55.1.1 5 59.5.2 702.55.3 559.3
559.l0 59.5.5 422.3. t
5
122.3.8 122.4.2 559.5.2 522.2.201 559.5.3
544.1
4r 1.3.1.2
Maintainability. assessmellt of Maintenance. defi nition Maintenancc of equiplnent -
341.1
accessibility lbr
462.t.20t
Pafi2 L32.12 Sec 513
Malagcment of Health and Safety at
Sec 559
121.55.2.4 559.5.1 to 559.7
conductors. selection and erection
provision of Main linked switch for installation
-
5
422.3.2 Note
-
conductor functional testing having total insulation
-
ii)
domestic. RCD protection rcquired 4 n.1.,1 exlribilions 7rI.559.5 extla-lovv voltage 1t5.4t4
fixing of
-
Part 2
enclosure used as protective
Main protective bonding -
Luminair-e supporling couplcrs
-
definition
Paft 2 5
522.2.20t 559.4. r 5 59.5.3 559.3.4 559.5.2
asseDlbly -
-
-
s60.7.2 Paft 7
70,1.410.3.l0
- at llxed lighting poiots - in FELV systeln - in reduced low r,oltage systcnl - ir SELV or PELV slstcrlr - not in circLrit relyiug on doLtble
Table 4F3A 522.7.2 102.55.2 '102.55.4 559.5.1.207 559.3 Note Table 55.3
synbols
Machines (see also Motors) - emergency switching off
Low Vbltage Elcctrical Equipn]cl1t
dcfinition
559.5.2
M
l3 r .l(iii)
Low voltage f.tcc.rlr.) Litltuge lotr)
-
switching for
temperatule offlexible cable thennai effects. protection against through rviring in track system fol wiring to LV switchgear and controlgear
4t7.3.t
ofSELV or PELV circriits.
of
swinrrning pools
-
1t4.1.5 416.
suspelldcd cable connection
-
Part 2
553.1.7 559.9
Appx 4
-
pal1s -
baIe. in SELV and PELV circuits bare. placins out ofr-each basic insulation of separalion
of
132.t4.1
Line. loss ol Live conductors. dclerntinatioD of
Li\e
portable. collnection of stroboscopic elfecl, avoidance supported by flexible cables, maximum mass of
523.6
Work Regulations 1999 Marina. definition Ma nas a11d similar locations application. scope of equipnrent for extemal influences houseboats, supply to exclusion isolatior, provision for notice. instructions for connection to shorc supply overculaent protection PEN conductor prohibited socket-outlets height above high water level
-
overcunelrt protection RCD protection individually requirements for supplies - connections to mains. examples
of
Appx 2 sec
11
I
Pafi 2 Sec 709 709.1
I
I
709.512 709.55 709.512.2 709.1 '7
09 .537 .2 .I
.
t
Fig 709.3 709.533 709.411.4 709.553.1.13 709.533 109.53
t.2
709.553.1
Figs 709.1 &2
-
nonljnill\ollagc fol wirins systcnls -
- dis bulion circuits - not on ol abo\'ejetljes. etc. - ovcrhedd cables or condrLclors - Lr[dergrouDd cables
709.3 Ll. L2 709.521.1
-
109.52t.1.4
'RCDS
cablts
brLried
'7D9.52t.|.1
522.8.10
fuses
511.1.2.2(i)
isolalillg de\1ces
531.2.1 Table 55.1
lLrltlirtiulcs nreehanieal ruaintcnance su
itchirg
d.\'iccs
531.3.2..4
Mass- rDa\iruLrln supportable by
i59.5.2
flexib]t'cablur
Appx
zl
llble 4F3A Materials propcr'. usu
Maxiulrn
133.5 134.1.1
ol
clemand. assessrnent
Marimlrur d.rrra d. \uirability suppl) 1i[
of
3ll.r
()1'
I13.1(v)
Mc'asur'es aguirrst electr otrragnetic disturbunces r,:r, l./ct t t't)nllt!:t t( t i.
Mechanical nrainrrnancc. delinition Mechanical nrairrtcnancr' srr itchin-l: -
-
/r
10.3.3
Parl 2 531.3.2
reelutilenrtrrts
Sec 46,1
cables
bLLr
-
ied irr r:r'otrnd
522.tt.10
ealthillg irrritr]gcurcnts ea hins colr(luato15
542.1.3.1(iri)
protecti!c.onductrx\
513.2.2 ro 6 543.3
542.i
5,:l,l.l rvit-itrg systcnrs
McchaDicaL:[cs\cs
' -
cables
511.6 -
ald conrluctols
522.6 to 8
i.3.1(ii)
eafthilrg allangelncnls
5,12.
cafihirg conduel0r'\
512.3
external influenccs
132.7(vii) l.]2 7(v)
lault curre l
7
-
heiiting condualor5 ard cables
5
plLrgs and sockcl-outl(-ts
553.
protective corlduclols
513.2.
Medical location. clefirition Mcdical locatrons - autonintrr disco llectlolr - additionrl pr'otection. not in rnedical lT systenl
-
sc
ioes
Annex A7l0
scope
710. I
selectiolr al1d erection supple)nerltal'y bolding" recluircmcnts t'or supplies
710.5 7
bonding
ol
ofothcr
scl-\.iccs, prohibited as ear'th
-
wiling systeln,
-
wiring systerl, protection agairlst
4 t
elec[otle
-
-
prolective 543.2
conductor
522.5
IJ systcnr _lN
7t0.41i.6
s)slanr
1tn.4tr.4
TT sysrcll
710..111.5
- definitioos lelarurg ro Pa2 - diagrams and docrrluentalion 710.51.1.9 - inspectiern and testing 710.6 - lightirg. to be supplicd b1 at le-ast l0.5
I 10.2(vii)
open-cast
1
I0.1.3(viii)
C i t t u i t-
fblrn of
Appx 6
provision o1 Minor works. definition
644.1.201 Parr 2
Mobile eqriipDett -
' so lection - definition
()1'
553.1.7
Pafi 2
ill non-colducting locatiorl
418.1 .6
llsed ouldoors, additional protection
for 4 r 1.3.3(ii) Paft 2 Mobile home, deflnition Mobile soulce, SELV oI PELV circLlits 414.3 supplied by Mobile rurirs. installations ofSec 717 '/17.t - application, scope ()1' autonlatic discolnection of supply bonding. plotective equipotential conneclioll to srLpply, exarnples of exanples ofunils gerlerators,
7l1.4lt.l
'7t'7.4tL3.t.2 Figs 717.1,3 to
-
7
1t'/.t
additiolul rcquirencnts
l'l' systen, provisiol of
710.415.1
110.41t.1
I.3. L2
breltkcr uDLl ('it'( it bt edkcrs MlDor Eleohical hrstallation Wbr-ks Cefiificate -
522.8 Paft 2 Sec 710
FELV nor per-mittetl
L3.2
542.2.6 as
Mines, installatiurs 1br - exclusion
522.6.l
l
522.5.2
'7
t0.4|.3.).
t0.4t5.2
710.313
-
L6
7
lu,o:otLraa:
lighting, availability of
t0.4t1.4
Metalwort- f.ree .1Ao t\pr)re./co Ll uctire1)fi1,\ ; ExI rd oct ) tts co duclirel)Ltrtt) -
5,1..1
autundlic diseonlleclioll of lauh
6
710.41-L5 710.53 r.3 710.560.9.1 710.56
5.12.
541.3.1
iug syster1ls
salely
Metals, pre!eDtio of eleclrolytic actiorl
410.1
-w
saf'ety
&
710.41 1.3.2. t
Mrniatulc circuit-breake$ se?
dclices tor
Mechalical 1;r'otcctor
710.410.3.5
co1Tos1t)1l
Seo 4,14
Measrres of proteclron against electl'ic shoek Mechanical danagc rre .ller /rrarh d/
for use
709.521.1.5 709.521. L8
Markrng lrcu a/i
-
plotective measures l1ot pemritted
)'7.55
'71'7
.4|.6.2
I]oti0c, infornlation to bc displayed '7t'7.514 plugs and corurectors tbr supply cofilection 7r7.s5.1 PME eaflhnlg, linritatio1ls on Lrse of 1t7.4|.4 socket-outlets - additional protection by RCD 111.415.1 - located oulside rLnit. protection of 7l 7.55. I supplies wilirlg systelns -
-
corncction to supply. llexillle
-
cable to be used gas cylil1der compar'lment,
-
internal
lestictiolls
tiriug ofunit
7
I
t7.3t3
I
I
7t1.52.1 -1
I'7 .528 .3 .4
'117.52.2
Monitoring devices
Sec 538
-
538.1.1 to
r9 insularioi, 1or IT systenrs
3
-
safcty services
560.5.3
Monitoring. in lieu ofperiodic rnspectjolt and lesting Monitor ing systerrrs. eairh
652.2 543.3.4 s
Monitor. residual current Motor caravan. definition Motor caravan installations Cdt'41 ctfi
i
fuse prohibired in halmonic currents
13 .7 .1
isolation of
.20(iit)
-
Pafi 2
over'cu ent dctection in
r.ee
control circuits corrlrol cquiprnent directiorl ofrotation excess tempcraturc protection exhibitiorls. isolatiou frequent stafting functional testing line. disconnection of nechanical lnai tenance. switchins
offfbr
-
overload protection re\.e1se-cun-ent bmking stc leJ. {apabrllt} ot ernclgenc)
-
startc.s. co-ordination of ovcrload
-
'tt.telrirre orT lbr'
proiectioll
463.t.2
L3
530.3.3
552.
463.1.1 552.1.2 463.3.3
422.3.7 711.55..1.1
552.1.1
537.3.2. 552.1.2 463.3.2
L
525.101
530.,1.3
I0.2(x) Appx 9 I
132.1 515.1
r
410.3.8 528.1
Neutral
-
conrbined with protective conductor see Pt\ . or.1rarol,1. 543.4 corrmo1l. lor groups ofluminaires on polyphase conuection to. TN-C-S system cross-sectional area ol
I
559.5.5
542.t.2.2 542.2
cunent-carying capacity in polyphase
544
314.4
condLlctor -
-
cilcuit
524.2.3
-
definition
Pafi 2
disconnection, provision for
53'7.2.8
-
emergency switching
..lechode $,ater heatets and
boilers f'ullctional switching
554.1
otf of
-
distribution ot. in IT systems
-
earthing ofreduced low voltage
465.2 463.1.2
4l1.6.1 41r.6.5 131.2). I
source
-
411.8.4.2 537.2.8
link
I
I
-
catavans
721.313.1.2
-
caravan parks
708.313 Part 2
delinition of'supply reduced low voltage circuits
SELV or PELV circuits swirnming pools Non-compliance, defi nition Non-condLrcting locarion. protectlon
o)-
- application of - basic requirentents - exposed-corductivc-pafis - linited to special situations - mobile equipfiellt in - protective conductorsprohibited - resistance offloors and walls - tesiillg Non-fl ane propagating, defi nition Non-sheathed cables. to be enclosed Notices calavans
-
- firellghter's switch - high protective conductor curent - marinas - mobile or transportable units - periodic inspection and testing - residual curent devices. periodic -
testillg warning altemative supplies - earth-free locations
-
I
3 13.1( i) ,1tL8.1.2
4l4.l.l 702.4t0.3.4.t Paft 2 418.1
4l8.l.l
to 7
418. 1 .2
4r8.1
4t8.t.6 41 8. 1.3
418. 1 .5
643.5 13
Pa11 2
521.r0.r 7)L537.2.1.1.1
Fig 721 531.4.4 543.7. t.205
Fig 709.3 717.5t4 514.12.1 5
I
I
I
410.3.6
Appx
522.5.3
- segrcgation ofdifferent currents and voltages, where grouped 515.2 - wiring systems and non electrical services 528.3
-
t Note
6.,1.2.2
552. t.
-'bonowed'notallowed
I
New nrater-ials ard inventions. use of 133.5 Nominal voltage /se., also Voltage,
643.10 zl31.1.1
135.2.
materials. betwcel protective I11easures segreration bet[.cen circLtits
t32.t4 46).2
463.3.1
53
stn ing clLrtents
t.2
462.1.201
5l -. J.J.2
stafiing. voltagc drop Moulded casc circLlit-breakcr-s.ice Lit(ttit brc,:tker, (. ittuit lr.eokers Mouldings. equipurcnt fixed or or iu Movirlg \\ alk installations. cxclusion Multiple sources. DC systerns Mutual dctdtnental influencc - elcct(cal aud non-electrical cquipment. prevelltion bctween
-
switching of
I10.2(iii)
of
43
reduced size 52.4.2.3 single-phase two-wire circuit s24.2.1(i) single-pole devices prohibited in t32.14.2
463.3
units
autonlatic testarting. prevention
aDd t'.ru1t
461). 162.2 53 7.2.8
o1, Regulations applicable orlly ro
-
5 14.4. r
543.7.1.203(iv) 538.4
MotoI contr-o1 Motor vehiclcs. elcctrical eclulpment
-
52i.6.1 to 3
idcntification of
.tt0I Idtions
camvans aDd mobile Motors -
132.t4.2
t4.12.2
514. 15. I
418.2.5 514.11.2
earthing and boDding connections 5l4.l3.l isolation of equipment 514. r l. t non standard colourc 5 14. 14. l plotectior by elcctrical separation4l 8.3 514.t3.2 - voltages nominal exceeding 230 V to carth 514.10. l NulDbcring system of Regulations, Notes on plalr Prefacc (opp)
o Object ol the Regulations
Chap 12 Pafi 2
Obstacle. delinitior Obslaclcs. protcctiorl by -
applicatiorl
ol
4r 0.3.5
411.t
-
417.2
basie requircments
Oti\hore installatiors. Regulations not applicablc lo
oii
-
110.2(!) 42t.1 .5
nuin bonding of serr,ice
41 1.3. L2 544.1 .2
-
gal',anic scpalation isolation PM[. ealthiug plohibited protecti\ e rneasu-es uot pelnitted socket-outlels individural protcction by oveLculrenl protection. individual types. glouping. placing of
-
RCD
-
larnpholders
lfue conductols motors
43
-
[elrlral collductor. IT systens
43 t .2.2
neutral conductor. TN or TT pamllcl conductors
431.2.
-
selecti\i1y
536.4.I
settings ofadjustable circuitbrcakers sor.rce. by
53t.1.3
-
scope and asscssllrcllt
Operating instructioos. salety equipnent and seI!ices Opcratiorlal condiliolls. equipnrent Or-drnary per'son circuit brcakcrs. precautiolls
-
730.410.3.5
&
6
-
730.531.3 730.513 730.55. r
-
Figs A730.i to 4 730.521
-
dcfinition tises accessibl!'to. lype of
'729.3
533.2.) 559.5.1.204
560.7.
l2
512. l
513.1.3 Part 2 513.1.2.2
3
r.r
431.1.I
Part 2 462.1 .201
537.t.2 3 1 .1(x)
oigin. oigin.
Sec 436 536..1.3.2
Pafi
2
of 3 13.l(vi) ofdistributor"s device 433.3. r (ii0
assessment r.rse
co-o|dination of charactcristics. lbr overload and t'ault cur'r-ent Protection
omissior
Sec 435
ol
ovcrload and tault cunent protection overload proteclion only safcty ser.\,ices selection and creclioD of selectivity shock proleclion. as
432.t 432.) 560.7.3 to 4 Sec 533 536.4. r
4t 1.4.5(i) 4r
1.s.2(ii)
.111.6.3(iv)
-
531 .2
short-cir:cuit protcction only tirnc/cr.ll'IeDt chal'acter'istics 1br
432.4
Appx
-
insulator wall brackets. exemption f|om t)ult protectiorl o\,el\,oltage conttol
3
-
placing out of reach
Patt2 431.1 43 | .2.2
systenls Or ercr.rrrent. lirnitation by supply
43 r.2.1
4 10..1.9(i)
413.4 417.3 ,l l 7.3.1
Ovelheating. plotcclion against Overload - cunent. definition - protection against - application of
-
-
Sec 424
Part 2
co-ordiration with l'aulf currert protection
Parl 2
line conductols ncutral conducto-. IT systems neutral conductor. TN or TT
513.1.3
Annex 8443
411.3.1.2
deinition
characlclislics
r
433.4
560.7.3
-
O\,ercul.1cnt deteclion
OvercLurent- protectlon against basic requirelrenl
at at
breakers Overhead lines
Oscillatiolls. lrigh ticcluency Olher ser\ ices. bonding of Outdoor lighting installatiolN see L igh t i I tg i t ts ttl I ati onsl) u tLlaot
Orcrcurrcnt. defi nition
lrF \
431.2.3
Overcurrent settiugs of cir'cuit-
129.t
,162. 1.201
-
55r.5
2134.3(iv)
730.,1u.4
maiu switch Origir of ai irlslallatiol - definition - isolation at
-
generating set hannonics
t|anst'cl switching equipmenl Ovcrcurrent pr'otective device (OCPD). definitioo Overculrent plotective de! ices -
7i0.3 ll. t.l02 730.i17.2.I
r.r'iring systcns Operaling and lraintenance sangway, Part 2 definition Operating and maintcnauce sang\vays Sec 729 - iiccessibiliq 129.5 t3 - gangwa)5. access lo 729.s t3.2.3 - protection bv ba[icrs or 729.5t 3.2.1 clclosulcs '7 - protection by obstacles 29 .5 t 3 .2.2 - closr-d rcstrictcd acccss areas A729
-
fundanlertal principle
supplics
-
-
' -
554.1.2 554.1.1 t3 t.4
431.4
-
543.2.3 not as protective conductol' 528.3 serr ices. ploxirnity to Oishorc supplies 1'or inland navigation Sec 730 730.1 application. scope ol 730.531.3 ilLrtonlatic disconnection by RCD cables. cable nrar)ageDrent systems 710.521.101.3 730.512.2.101 eqLripment. lP protectio[
-
elechodc wat!'r heaters and boilers
552.1.2
-
1illed equiprrreut pipes -
-
-
lnotoLs
ornission of onlission. fbr safety scl_vices parallel cooductols position oidevices 1br' protective devices - lequirements lbr
-
Sec 436
selection of Ovenoltage. protcction against . alrnosph{rrc oflgir, or duc Lr
Chap 43 430.3
-
switching ofequ\)menl
categories
Scc 435
552.1.2 560.7.1
430.3 Secs 432 & 433 533.1 & 2
Sec.143 443.6 Table 443.2
-
-
deviccs (SPDs) -
-
Sec 514
oonneclion of rn eonjuncrion rvith RCiDs overcul'rent proiection of selccrior cliteda
E le.
534.,1.8
Reporl
fundanrcltal principle
534.1.7 534.4.5 534.4.1 131.6.2
risk assessment l[cthod
443.5
scope and objer'1
433.1
-
withstand values. eq pmcrlt OveNoliages.tl'a1lsrcnt assessrtlenl of couscqucncc of couhol agaiDst risk assessmel)! ltlethod -
-
-
Pipes -
33
4213.2
r.1(i)
443.4 443.4 443.5
Arnex A443
Parallel couductors - tauLlt crulent protection of - ovelload protection of I'aralLel operatio ot gcncutil]g slj1 -
-
ple!cotiou ol'!vith dislributor's
-
with distribLrlor's network.
,retwolk, precautions
,116.I Note 523.1
434.4
433.4
5
51 .6.1
requiremellls lbr Parallel opclation. sality scl\,iccs, sourccs for Patk. r:atavan sr,c CZa,ral pra* Palrial sLdcctivity, dciirlirion
551.7
llaltitions, cables in Pdrtitions lbr segregntion of circuils
5)).6.202 & )
PLLY sec Ptulccti'e etlru h^r rtllcge, clelinitron PEN conductor-,
560.6.9
Pafi 2 528.1(iv) 528.2(i) P'dn 2 Pafi 2
detiuitiol
PEN couductors oable enclosurc prohibited as
-
543.2.10
idcntillcation 5 t4.4.3 isolarior or swltcliDg ol', prohibitcd 411.4.1 461.2
nol pennitted {,here tir-e r'isk rcsidual cufent dcvicc with. prohibitcd
422.3.t2 411.4.5
543.4.20t selec!ion arld erection of I'endan! Iul1fluirc -
-
caravalls flexible cable lirr'. supportable by
543.4 721.55.2.4
rraxiruulr
rDass
tlrass sLLspendcd
Pcuetratior of buildiug, load beanlg intcgrity to bc assurcd Pe rrdic ilspection and tcsting /ree .tlio It$pection, pcrio.li() -
-
-
eafth electrodes Ibmred by
Appx 2 sec s(iii)
6zt3
I
542.2.2(i) 542.2.6
pipes oi1 see Oil pipes water see ll/ater pipes Placing out ofreach. prolection by - applicatiotl ol gas see Gas
410.3.5
4t'/.1
Pailrt, geneftlly not as insulatjo Parallel calllcs, selection and clection leqLlifcDents
-
see Authori:ed, Skilled, lnslIucted, Otdin0rl perso s
Persons
"fable
P
-
I ns tLl I L!t iafi Candit ia
Sec 442 Sec 431
exanlplecalculaiiuls
tt'i(ol
Petroleur) (Consolidaiioo) Regulatiors 2014 Plrase couductor see I he conducttt Phase, loss ofsee lile, 1r.,.sl orl Phase sequence, vcrifi calion Photovollaic r'ee sb/at phobtoltoiL-
tcnDoraly, due to t'auh m HV or LV systenl
Periodic lnspectior Repon.ree
Appx I6
Appx 4 'Iable 4F3A 559.5.2 522.8.14
341.1
by skillcd pclson(s) calavalls tiequerrcy ol
651.5
limitatious l[oniloli1'lg
653.2 652.2 514.12.1
nolice on
Fig72l Sec 652
reconlrendation lbr
r35.r
r'eqLrir'elnenls
Sec 651
-
411.3 Fig 417
arm's reach
-
bare live parts overhead liies with obstacle present PIan ofthc l8tll Edrtion. Notes
411.3.1
41-/.3 41'7.3.2 o11
Plug, definition Plugs -
-
Pari 2 121.55.2.6
clock corstILrctioi siles emergeucy
5s3.
switchilg otl
53
-
f:rurctional extm-low voltage systelus 1'unctional swilching by fused. selection of high plotective coDdLrctor curaerlt
equiplnent
-
7.3.3.3
140 55.1
clrcLlses
-
.5(i)
by,
prohibitcd l'airgrounds. anuscllrclrt palks aDd
-
r
704.511.1
-
-
Pretice (opp)
,11
1.7.5
-lable
537.4 553.1.3 543.7.1.201
s43.7.1.202(ii) ilNlantaleous water heaters nol to be supplied by isolators rnccharical n1airterlarce, ibr
switchirg otl'lbr
554.t.1
fablc 517.4 537.
rnobile or tlansportable urits rcduccd low voltage cir-cuits selection and erection of SELV or PELV circuits
shavers special cilcuits Plugs and Sockets etc. (Salety)
7
t.i
t'|.55.1
4tL8.5 5
53.1
414.4.3 553.1.5(i1) 553.
L5(iii)
Appx 2 scc 9 Regulations 1994 PME see Prctective ntultiple eu'thing Part 2 Poirt (in wirirg), dclinitioD
Pola
t),. rest of 643.6 Poles, rcinforced concrctc. cxerDption
from fault protcction Polluting substances, wiling systerns
410.3.9(ii)
exposed k) Pontoons see Mdl-irr.rs
522.5.l uncl
sitnilur Scc 709
Po(able equipDlent.ree MoDile eqnip ie t Portable g!-nerating scts Potentially explosivc atmospheres. installations irr applicability ol the Regulations to
-
eqlipmcit of statutoly regulations. etc.
551.4.4
I
lo.1.l(iii)
t32.5.1 Appx 2 sec
5
i Potentiometer, not as FELV source Power demand. suitability
equipment for Power factor Power sources lbr genemting sets Powefirack, definitior Powefirack system. def, nition Powefirack systcl]1s - curTeDt-carrying capacity - rating under lault conditions
-
standard
lbl
-
bonding, sclection and erection
.4
.1
512.t.4
'Class II'equipment in relation to
4t2.2.2.4
3
3 1.
l(xii) colour identification
Appx
continuity of
8
543.2.2(l)
cross-sectional arcas
5,13.1
electrically scparated circuits
411.3.3 418.3.4 543.3.s 551.4.4.1 513.1
543.2.2,4 & 6 544.t &2
-
521.201 I 15.1
of
1
1
-
134.1.1
Prospectivc fault curent Pafi 2
definition detcmination of
434.1
643.1.3.201 measurelDcni
of
-. suitability of protecti\
643.7
.3.20t
e derices
432.I to 434.5.
3
r
Prospective shoft-circuit culTent at
origin, dete dnation of
exposed-conductive Parts used as gencrating sets, Potlable higlr cuuents in identification of
-
422.4.2
-
inspection of installation of insulation of mobile urlits
-
preseNation ofcontinLlity PV installatiolls residual cu[ent device. to be outside lnagnetic clrcuil of ring lirrar
.11
-
-
Chap 41
protectivenleasLLres safety sen'ices
s60.6.8.2 560.6.9 560.7.6
Sec,12l
Protection againsl ll re
Sec ,122 Sec 527 Sec 532
642.3(viij)(c)(iv) 543.6.I 543.3.201 t7 .41t .3 .1 .2
1
in
circuit
selcction and erection
1.3.3
Sec 423
of
Protective devices.tee Ot pt'a tect
iv
derices
;
13 1.,1
(
-t|stet16: Una[e] \'oltage,
Protection againsl o1'en oltaces
ChaP '13 Sec 443 Sec 534
Protection against urlden oltage Protection for safet! Protective bonding corductor. definition Protective bonding conductors Prctective conductor'- defi nition
Chap 42 Scc 445 Pafi .1
-
Paft 2 Sec 544 PaIt 2
e\cessi!e
definitiofl
-
high, infomation lo be pro\ ided
-
ag culNral
Prcmises bet\\,een separaie inslallations
oleclion
position ol Protectivc earlhing.eee
514.1.1 514.8 132 14
ELt t l h i n g.
definition
Part 2
Protcctive equipotential bonding see ELluipotential bo di11g, defiIrition Part 2 Protectivc cxtla-low voltage (PELV).
definitiol
Part 2
- bathroorDs
5.i3.7.1.205
55.1. L,l boilers 53I .i.2 residual cu[ent de\ ices and suitability ol eanhing alTangements
Protective conductors - acccssibilit-\ of connections
y
543.7
HV electrode \ater heaters and
for
ute n t
Part 2
i31.1(viii)
equipment rtith high. requirements for-
543.2.1 714.411.203 102 415.2 543 3.3.101 543.2.4 643.2.1 543.2
Protective exralow voltage systems '705.414.1.5 agricultural pretnises - application as protective measure 410.3 3(ir')
Paotective colductor curent assessmeDt of etTects of
2X1rr.3.roU,
al
Protcctive dcvices al1d switches iderltification of
-
531 3.1
un?nl derices: Monik 'i|g
Protection agairst o\erculTent
Protection against thennal efl!cts
et c
Res idu
418.1.3 543.3 712.54
Sec 543 Sec 544
sepamtc - street clcctrical fixtrte - swiirring pools - switching prohibited iu - l0nnn: ol less to be copper - testing of - typcs ol'. descdption
Appx l6 1l I.3
t4.4.2 5t4.5.2
5
non-conducti11g location. prohibited
313.1(iii)
Protectiorl. additional Protection, against bums Protection agairst electlic shock -
-
412.2.3.2 514.4.2 Table 5l
of
543.2.5 to 9 543.3
434.5.3 521.4
1i2.
t.l
collrbined \\,ith neutral conductors
Projector. mininu:n distance of, fioin 422.3.t combustible IrlateriaL
-
721.4 t I.3.
551.1.1 Part 2 Paft 2
Sec 515
Proper materials. use
+1
133.2.4
Pafi 2
Premises s bject to liceflsing Prevention olmutual detrimental influencc
Sec
708.i)-r.l - l-l
$iring syslem -
defnition in flxed ilsta]lation
-
of
caaavan parks car'aval1s
Appx 8
voltage drop
Prefabricated
4t
of
-
l1]overre,1t
706.410
constructlon
5-+1.3.1
-
!:rhihitions- shows and
3.l0(iii)(e)
stands
704.410 3.10(iv) '7 01 .41 4.4.5 '711.114 4.5
exposed-conductive-pa1ts. earthing
ol
I
106.4t1
sites
-
05.5,1,1.2
701.55(vii)
414.4 circuits. requirements for conducting locations with restricted
rll. L3.l(i0
5-ll. I.3.3
414.1 '701.414.4.5
114 4.1
I
411.4.t
-
4t1.3
Reference Method 1br cable sizing Regulaliot1s, Statutoly -
-
live pafis of rnobile sources for no1ninal voltage
-
plugs and socket-outlets for
4t4.4.3
protection by use of
4t1.2
4t4.2(1)
-
414.4.5
-
-
4r0.3.6(ii)
elcctrical separation fol supply of more than one item ofcunentusing equipment
-
410.1.6(iii) 4r8.3
eftects of exclusions ti'onr scope of object of relationship Nith statutory regulatiorls
Chap
410.3.6(i) 418.1 410.3.5
obslacles
410.3.5
4t7.3 Protective multiplc earthing (PME) - cornpliancc with statutory regulations - construction sites - definition - elcctric vehicle chargjng irNlallalions Libitions
Appx 2 sec
3
704.4t1.3.1
722.4t t.4.t
r 10.
Part 2
412.2.t
341.1(iii) 31 1.1
I
164.2
I
ReportiDg
Sec 653 Part 2 708.1 Part 2
-
Pnfi 2 41 1 .3.-l
-
53r. r.l 701.41I.3.3
auto-reclosiog
batlrooms
ir walls or pa itiols protection by
I
cablcs
522.6.202 522.6.201(i)
'"ks
c.
708.415.1
721.415.t
con cablc an!
I
706.,110.3.10(iiD(b)
5l1.3.1
idcntillcatr
:
isolatron or
1.2.1
'riJ,,rii..r- .-.J{ - S+ 3 ^
r'."iduol .urrenr.l.
:-
-
i-i5: i tlurrblr cablr l.rr. ttt.rrittrt.tl titoc-oq ': b) --9.$:-'^r-v
i ,.
.l
rrras\ \u.perrJcd
.415.1
L410.3.4 I r .41
'i o) '-"sNS.d. -Y
,-t* . .. ES :, P..rrctrJtrUrtol,burldrrrg,loa.1b" *S j - rrunrrorirrg 6il.: o' - irS*i5:i 514.12.1 rl,riL(,rr , " 135.1 - rcconmendation tbr
1.3.3
/40.410.3 740.415.I
_E
!
:r.:.ror ;rr .u t.t
-o --S .I -:.,,
'"-.S^Si triS"Y-f \^ '_' v *\
,S
+1.5
eS
3
{
.rrppun:rbt<
I
'4t0.3.10(ii)
-
-
I
70s.41 l.l 105.422.1
PE\
-
r.2(i), (ii)
Reliable dcsign Remote switching fo| llrechanical nlairtellance Repoft see Electriccrl /ti.ttdllation Cotklitiot Report
PE,
PE\
I4,I
Chap I I
Residual current device. dcfi nition Residual cu ellt dcviccs (RCDS) - additional protection by - agriculturalprcnriscs
|.4|.4
140.4) I .4 544.1.1 109.111.4 111 .411.1 1t1/l
lor
I
of
Repoting. def,nition Rcsidertial park honcs Residual cunellt, definition
Part 2
'7
Chap 12
lit'e
4t7.2 placirg out ofreach
scope
12
110.2
voltage ranges dealt with Rcinlbrced concrete.\ee S1ee1 Reinlbrced insulation. defi nition Reirllblced insulation, of equipment Rcliability of equipme|rt for intended
410.3.3
for general application non-conducting location
l,rctors
120.l r3l. t.3 131.5
4t 4.3
eadh-free local equipotential bonding
ll4.l
depattures fiom
4t4.4.2
separation froDl other circuits sources tbr Protectivemeasures. shock
-
Appx 4 sec 7.1
list of relationship of the Regulations u,ith Regulations. The -
-
703.4t4.4.5
saLulas
4l 1.i.3
RCD nol re.luiled
532.2
;
7
02.4t0
.3
.4.2(ll)
554.1.4 Table 537.4
r
4t).3.1
,ts cssels
709.531.2
717.41Ll 7 17.,11 5. I
730.531.3
ts, prohibited 4t
Sec 651
t.4.5
543.4.201
lken, where r
nray op.'mte
5l L1.4.201
I
prclcrrcd. lbl shock prolection in
-
I
proteclion by. not recognized as sole
n'reans
-
Rotatirg machines /.!c., dk.) l4Llchincs. l4otot s) - emergency switchirg off fbr
415.1.2
protection against fault cunent, in
-
516.4.1.4
senes
protection against risk offire protective conductor still required reduced lorv roltage circuits with required. lbr certain socket-outlets r'equired. for mobile equipment
Sec 532 41
l.i.1.1
411.8.3
Safctylightirg.medicallocations
4l1.3.3(i)
Safety. object ofthe Safety service" Saf'ety
703.,1ri.3.3
531.3.I ro6
5i64I4
in lT s-vstem
Table 41.5 ,111.6.3(v)
in TN system
4l1.4.4 &
5
u.5.2 &
3
4r .4201
in TT s)'stem solal photo\olraic (P\') supply
4
537.1.3.1 Note I
Sec 552 I
selection and erection of selcctivit-v benr een sirock protection b-v eafih fault loop impedance
-
554.4.2 & 3 Scc 753
433.1.3(i)
of
S
saunas
-
exciter cir-cuits of selection and erectio[
415.1.)
4l r.3.3(ii)
ouldoors
-
Road-waflning. cables fbr
4t | .5.2
l_ svsiem
-
-
1t2.4t) .3.2.1.2
systems special locarions street fumiture
Part
swimming pools
702.4t0.3.4.t
7
71,1.411.3.3
Regulations definition senices -
710.560.9.l Chap 12 Part 2 Chap 35 Chap 56
560.1 application. scope ol automatic supply. availability o1' 560.4.1 chamcte stics ofsources ofsupply I32.4(i) 3 r3.2 circr-rits
-
560.7
ol 112.4(ii) fire-resistancc 560.7.2 - independcncc of 560.7.1 560.'7.6 - lifts 560.7.8 - segrcgation. recommendations for528.l Note 2 560.4.1 - classification ofsupplics lbr' -
-
deternination
contloigcal. location ol drawings of installations
560.7.5 560.7.10
equipment, fire protection
560.5.2(ii) 560.1 Note
-'testing
702.53 702.55 641.8
-
643.10 314.1(iv)
operatinginshuctionsfbr prefe ed plotective rncasurcs for
702.4t0.3.4.3
tripping. un$anted
5l1.3.2
-
types Residuai operating curent -
5i I .1.3
-
additional protection
41s.
definition
531 .1.6 Paft 2
-
l
.l
earth fauh loop impidaoce in
relation to
4t l'4.4 Tablc ,11.5 5I1 ..1.2
-
selection of Resistance area
(ofao eanh electrode),
delinition
Pafi
-
.l10.
flot a Protecti\e deri!_a Rewirable fuses see frri.:. ;erzr
13
-
arrangements f{x houiehold and similar premises circrLit protecrir e .to:hrtor of
defirition lbr high prorecdr
e
15
5,13.2.9 Part 2
54i.7.r
oi
lti.
560.5.3
1.204
6.+3.2.I
l10.i.l Ripple-tree \ oltage- deinfuioo Risk assessmeDt - documented ui.re RCD FoaeLrtion ..111.3.3 of socket-outlc nx prorrded - method. relatrag r) protection 1.11.5
560.6.5
low po*.er sLrpply
560.6.I l
&
1l I
I
nlonitoring
560.6.14
-
I
I
not capabie ofoperatron in operation in parallcl rccognized
-
Note
.-.:odrror
culrent equiprDe overload prorectioo test oicontmurr]
Appx
560-'1.),2
irldcpcDdcnl
parallcl
-
Ring final circuit -
-
560.7.3
-
-
L5
l.l
protectioD
required to operate in fire conditions 560.5.2
532.3 -.1I
oad
560.6.l3
53 8.,1
-
ofove
2
Appx placing out of reach Residual currenl rFoiror (RC\I) applicalion
omission
-
,118.1.5
Resricted accrss. oblaclas and
of
sources 560.6 accessible to skilled or inslrucled pcrsons only 560.6.3 as fixlrd equipment 560.6.2 560.6.10 batteries 560.6.10 central pou,cr supply 3 13.2 characteristics 560.4 classification of gencrating sei frcd dA_o Getleratitlg
Resistance of irsularing floors and
walls
examples
time. changeorer LmiDtcrruptiblc power supply (UPS) - usc lbr other purloses - ventilation ollocation switcllgear. localion of
wiring systenls
560.6.8 560.6.9 15 r.1 560.6.1
560.4 560.6.12 560.6.7 560.6.4 560.7.5 560.8
Salety signs r.,., IIo//.e.t - llurning Salety Signs Regulatiors 1996 Saf'ety sourccs tbr SELV ard PELV
Appx 2 sec 10 4\4.3
Sauna. dellnition Saunas -
Part 2 Sec 703
-
703.41 t.3.3
additionaL protection by RCDs equiprrent. selection aod ereclion heating appliances
lighting controls scope olapplication SELV or PELV shock protectioll rfi
703.51 703.55 '703.537.5 703.1
103.414.1.5 703.41
I
switchgear. loaalion
of
-
703.537.5 703.52 103.32
\\, iring syslctlls fin
Schr:dule rci: Di.rgrratt.r Scllcdule ol ilisPections
7()2.55
(lhap
36 Sorvice. coltiluity ol i t:es se tt Sit/ety Salety.!.'c Services, Shaver supply units itl balhrooms 701 512 2 & 551'15(ii) Shavers, plugs aod sockcr-oudels ShlDs. electric.tl equiplDellt on boarJ, llU'2rr\ I tire Rrgttlaliurrs rrut appri.abl< Purt 2 shock curent.
Appx 6 Chap I l
Scr',"'cnirrg nritterlals. lbl lixed cqulprnctll
Screus, irrsLLlating, irr Ciass
421.l .3(ii)
Ll!
I
fi
nd
I I
d
I i ] ilt
I
e
t
Pa[ 2 Shock. Shock. electlic, protectiul agairst Jee
6a2.3(vii)
B,lit
k'c )
515.2 52 ii.3
.'/rr?r/r,
Sec 536
bet\\'eell dcvices irl scrics cooldi1litlion rcquirelncnts 1or
Pafl 2 cielirition dolurrcntxtion lor der' ite selcction 536.5 Iiri|grourrds, R(lD protcclion of 740.410.3 cllcults lo frc\ida 36 r.1(i0 tor ctttrtilluity oi sel'r ice 705.s60.6(ii) livestocli ve tilation cir'ctliIs fo]'
SELV ree
5c7-.,rr;
i,,',,,i-.',
-
Scpa|ated cxtra-1o* \oltage (SLLV
r..
li'lnge
B,LuJ
I
Palt
41t.1.4 Fig A5 3.1
-
col1ducting looatjons. in
electrical separalioll. plotection by
413.l 4t3.3.2
-
FELV source tbr
411.7.4
mobrlc or transDortable units. IT rvsrenr lbr PV power systems
-
Part 2
706.4r3.1.2 Pnfi 2
defilrition
).
7l I
ugricuilur-rl Pr-enlisc\ application as Prolecli\'a llleasure
05
.4t
Simultaneously accessible parts -
4 .4 .5
- additional protcclio[ by bolding - definitiort - earth-flee local bondirlg locatiors - in lT system. precaltions - live, waming ofvoltage between - non-conducting locatjoDs
410.3.3(iv) 414.1
'70).414.4.5
batluc,otls
701.5 0t.'7 53
T
1t4.4 circuits. rcqlLirettlliDis lor conductillg locations \1i l reslrictcd 706.410.1.10 '7 06.414 704.4r0.3.10 sonstruction sites '7
04.414.4 .5
equipl erlt, protcclive scparatioll of 414.4.1Note '7 1t .4 14 .4 .5 crhibitiolls. shows and stands exposed-condLlclive+a s ol li-shtirg jnstallations. extl a-low
\oitago
lile parls ol mobiie sources t'ol' DoDlinal voltagc plugs and sooket-oullels lix' plotection bY usc
ol
414.4.4
fionl olhcr cilcLrits
t
414.4.5
4t4.4.3
&
2
03 .414.4 .5
414.4.2 114.3
.3
Part 2 418.2.2
suppleDlentary bonding between,
protectior by - with automalic disco lectioil Single fault in IT system ser' 1I q sten, rtrst./Ltt!lt in
4l1.6.1 51,1. I 0.1
4l
rJ.1.2
41 8.1 .4
411
.3
1
&
,115.2.1
.l
41 1.3.1
lil
in
524'2'
Skilled person (clectrically). defiflitioll Skilled pelsons - and saf'ely seNices sotuces - corltrol ofsaltty services by good workmanshiP bY - obstacles petmissible r'vhete access restricted to - Dlachu oul of rr'ach penl}issible
Part 2
-
551'8 1 Pafi 2
whe;c,l(ce..rc
stationarJ batteries, acccss Socket-outlet, de{initioi
rr
)
.2 I .2
415.2.1 & 2
placirg out ol reach
oiea of rreurrll
414.2(i)
553.1.1 414.2
I
12.4t1
Single insulatcd cables.sr:e Norrsheullted ccfiles Siucle-ohase crrcttit. cros\-scctional
115.4t4 4t 4.4. 414.3
'7
scparation
-
r.4l I b.ll
'712'3122
cxtlalou !ohage systenls '7
2
Simple separalioll -
531.2.2
d.tinillon
Pat't 2
Signs. electric rec /)rr.hatgc liglltirg Signs. waming rce Noli@-t lThrning
Parl 2
Senrictrnducttrt clovtces i.{)latidl. rlot lo be usad 1or uot xs FLI V sourec possibie lauh 0urrcnts Scmi clulosed tlrscs r,:r /lrr,:.r'
Sepalated
Siqrmllirle ciretLrts
raeil c\tt Lt lo.'\'\'olrLlgc
delinitioll
delifition
313.1(iii) installation Shofi-circuit cunert rating- defi rlition Part 2 Shoft -circuit prolcctive dcvice. Pmt 2 definition Part 2 Show iee f,\'rlriliol?J, defi nition Shower rooms r.rc 8rrllr?or?.t
536.4.2.2 to 1 536.4 53 6.3
back-Lrp proteulroll
tc,ttott.
Shofi -cilcuit current, pr-ospective, detennination ar origin of
Pafi 5
Sclectir'ity i\r'c rrlstr ( a4r'.linutkrt)
f.t lt P
ptt'rtLti,ttt;
P1\'tr'r'tiott Ltgltltttt L'lct-n'r. J*'t A Shofi-circLrit cul]eoi /see also FLnll
528.1
non-electl'ical selvices Sclection attd eretttoll of equipnlellt
-
dctirlilion electic, deflnitior
412.2 .2.2\i1)
cilauits ditlcrent cuncnts aod vohagcs
-
tU
Il
suitablc, Prcsetlue o1 Segl:gatrort lrce rrlv,, Matlal
l
fbr
421.1.2(i'
Sca1s.
I
Separation, sin1pl..tc.r Si/rPle
644.1 653 2
ol lhe Rcgulati0ns
I
Sepalrtiun. (jle(trtca[. it\ Prute(tion agairlst sho(L \L-L ElLLtl ttLll
Appx 6
Scope
.4
.3
102.414.4 702.51
644.1 653.2
Sclrcdulc ol'tcst rcJulls
'102.410
swil1nrinS pools
I
5m 6 3 560 7'5
I34.l l 410.3.5
4lU'l'5
2
Socket-outlets additional protection for ag cultural and horticlrltural prcmtscs
-
t.t
705.4r
't05.512.2 705.553.I
-
-
553.1
4l 1 .3.3
bathrooms
701.4t3
bonding to boxes, etc. caravan patk installations
701.512.3 543.2.1 708.553.1 '121.55.2.2
caravans. itt circuits lbr -
-
disconnection times earth fauit Ioop impedances for
clocks. for constructioli sites
1t1.3.2..2 Tables 41.2& 5s3.
3
-
r.s(i)
-
prohibired exhibitions. shows
-
emergenc], s\\.itchilg
-
-
onshore uDits to supply vessels
Protected Soldcred SoLu'ce
559.5.1(v)
provision of reduced low loltage circuits selection and erection of SELV sysrcms
730.55.1 zli r.3.3(ii)
<J".1.5
IZCJ
Spotlight
42).3.1
pa"]r
l
Spur'.
definition
Pafi 2
Stand see Exhibitiotls, definition Standards. British, rcfel.enced in tbe
I'aft 2
Regulations. list Stardards. compliance with
Appx I Scc 5l l
Standby supplies
3
ll.2
553.1
4t4.4.3
.l & 2
swilr'uning pools
'702.4 I0.3 102..53
8.3.5 553.1.5(
525
ii) .1.t
&
assessment
ofeffects
of
suitabilit), ofequipmenr for Static conve|tors Stationary equipnent, definition t
/ a ti
331.1(v) 552.t.1 551.4.3.3 part 2
ons,
reiDlorced concrcte poles, exernption fi'om fault protection - reilltbtcement ofconcrete. use as earth elcctrode - structural netalwork" bonding of Storage balteries for safety senices Stored clectrical energy Street i'umi1u.e /rec also Hightal,
-
)n)
Appx 4 sec 2.2 Table 483 554.4.2
-
Steel -
Soil warning. cables a1ld condLrctor-s 3
Solat gai[ see Soltr]. rodiotion Solar photovoltaic (PV) power supply systems -
-
appliances locations
Spacc heating Special Specifi cations see Stardar r/s
-
4 i 1.8.5
41
for
onc
526.2
wher'e more
Statutor'y regnlations.t ee Re gt
703.537.5 553.1.7
separated circuits shavers, for
voltage dlop at Soil themtal resistivity
ofenerel. earthmg
Startcrs. motor.rec Molol,J Staning cunents -
'/ t1 .1t 5
553.1
-
il3.?,1,^"t"
connections
Sec 551
537.1.3
locatiol
against
2.1
71t.42).1.2
outdoor equiprneltt. for. PELV systerns 4t4.4.3 prohibited - 'Class II'citcuits or installations 412.1.2 - emcrgency switching off 53 7.3.3.3 - instantaneous water hcateN/ boilers 554.3.3 sauna heater
Appx 4 sec
5s9.4.r(iii)
553. t.201
717.s5.1(ii)
-
of
4)2.1.2
709.533 109.531 709.553.1
offfbr
account
t2.522.8.3
543.1 .2
marinas
mobile or transportable units
7t)5t))l
s43.7.t
'109.531.2
-
-
553. r .6
Table 537.4
mechanical maintetlance. switchins
-
Table 537.4
household il1stallations. selection isolation. lbr' lighting points. ar fixed
-
712.522
7
lhil)
4lL.7.5
.l
'712.5
\\'iring systenls
waming iabel. live paffs
7l t.4t 1.3.3
I5.I
7 t 2 .537 .2.2.5
712.4
7.3.3.3
740.2t
2
712.t
\\ifing systen to be suitable for or
1.55.7
&
Figs 712.1
saftty. ptotection for selection and erection - equipmcnt
-
t2.5t3.1
712.433 712.54
of
-
53
functional extra-low voltage functional switching, for height of high protectile conductor current equipment
7
overload piotection on DC side protcctive bonding conductors PV arrays, exirnples of r'equircments. scopc
t2.522.8.3 t2.434.1
't 12.444 .1.4
fo.
rating f'afiors for cables. don't take
740.55.7
-
maintenance. access
-
7t
systems
712.537.2
lightrling iDduccd voltagesntinimization of
722.55.t0t
offby.
fairgrounds. etc.
isolation
7
-
704.5t 704.53
electric vehicle charging
7
Solar radiatioD PV po*cr supplies
704.41
-
cxtcnlal influerces. expected fault prorection. AC side
accessibility for $,ork on eqlripment 712.5 lj. I definitions associated uith Part 2 PV listing earthing of DC live conductor 1D.312
-
410.3.9(ii) 542.2.21,t) 41
1.3.1.2(v)
351.r(i) 462.4
potrer slpplies) -
definition Palt 2 doors in. barier or'enclosure to be provided 7t4.11]..2.20t extraneous-conductive-parts need rot be bonded to 7t4.1tl.3.t.2 isolation and switching, devices for 7 t4.537.2.1 scope
'714. t
Stroboscopic cfl'ect, avoidance of 559.9 Structural elemcnts, peretration of by wlllng system 522.8.t4 StructLrml metalwork. bonding of 41 1.3. r.2(v) Substatioos
S:rnlight see Solcu radiatiott
Sec 442
Super'\
ii.d
insrallations. protective
nr.iiuras applicable only in Supplemeniarl bondirg conductors, .elcction and erection of Supplementary protectivc equipotential bonding - additiol1al protcction by - ag culturalarld ho icultura] prclnlses
4 t
0.3.6
544.2 '705.544.2
4t5.2 '705.415.2.t 705.544.2
-
batlirooms and shower rooms 701.4t5.2 conducting locations. resfficted 706.410.3.10(ii0 conductors. coltinuity of, testing 643.2.1(i) conductors. selection a1ld sizing 544.2 disconDection time not ntet 4r9.3
-
inspcctior
6,12.3(viii)(c)(iv)
livestock, Iocations for
705.415.2.1
-
extr'aDeous-conductive-parl
used as
conductol lor
543.2.6
710.4t5.2.t swimming pools
702.415.2 702.522.21
702.55.I
-
where static convellor illstalled Supplerncniary insulatioD. appl ied cluIlD{I crectton
Suppiementary insulation, defi nition Supplier.rc., D/.ra7.irrtor
551.4.1.3.1 112.2.1.2 Part 2
Supplies -
-
-
-
marilus
Sec 730 709.311.1.2
rcduced low voltage circLlits
41i.8.4 Chap 56 4t 4.3
-
411.7.1 Sec 714
safcty se1-vices SELV and PELV
earfting
31i.2 542.1.2
asscssnlenr 3lj.l
effect of installation equiprnellt on switching arrcltgcments fol safety
supplies the Regulatiors not applicable to Supports lol cablcs for fixed uir.ing
-
Surge curent. definition Sulge protection, overvoitage
331.1
560.6
l10.2(i) 521.10.202 522.8.4 & 5
P^rt 2 Sec 443
Appx
16
Surge protective device (SPD),
definition Swin]ming pools - elect c floor heating - equipment enclosurcs, protectioll affor ded
by
Part 2 Sec 702
702.55.1(i) (iii) 702.512.2 702.55.1 102.55.4 702.55.4
equipment, cunent-using fixed equipment in zone l lighting in zone I protective measurcs, application of 702.410.3.1 scope
702.I
102.410.3.4 702.s3 '702.4t 5.2 702.51 702.55.2 702.52 702.32 PaIt 2 132.14.2 554.3.3
462.1.20t 530.1.2 55 5.1 .3
462.t.20t Pa112 526.4 r5.2
witllin
5
70 r .512.3 537.4 463.1.2 463.1.4
l_12.14
461
2
54i.4.1 prohibited in protective conductors 541.3.3.101 silgle-pole, prohibited in neutral t 32.14.2
L3
530.
step-up tEnsfb, Dlers- for Switchgeat assemblies, functional test
-
systelns
ol1
- bathrcoltls - lirefighter's - lamp coltrol circuit - mote than one source - position of, liDdamental principle - prohibited in PEN conductors
704.313 413.3.2
highlvay power inland navigatiofi vessels. wllen befihed
iustantaneous water heaters/boilers rnain selection oftype stcp-up transfonners
condlLctols segregation Switches -
-
740.113
dcfinition inserted in neutral
-
72t.3 t3.t.2 706.410.3.10
7ll.3l3
wiring systems zolles
Switch. mairl. lbr installation Switchboard. deliniriorl Switchboards -
caravans
conducting IocatioDS, restl icled construction sites electrically separated exhibitions. shows and stands fairgrounds, etc. functional ex[alow voltagc
of underwatcr luminaires
102.4t4.4.5
S!vitch, linked -
-
514.15.1
Supply, nature of, Supply systcms, prblic -
-
SELV circuits SELV supplles socket-outlcts - suppletncntary equipotential bonding required - switchgear and controlgear, locatioll
alternative, waming notice
standby. ass(]ssment Supply arrangemenrs a11d installation
-
-
definition diagmm lbr
I
555. L3
643.10 Palt 2
514.9.1(iii)
dillerent voltages. waming for isolatiot and switching
514. 10.1 Sec 537
for sa1'ety services labelling of nlarking of
51,1.l.l
560.1 .5
531.2.7 531.3.2.4
selection and erection Switclring -
of
Chap 53 Chap 46 Sec 537 517.1.5 463.1.3
- between earthing anangements - cuflent-usiltg equipment - devices. back-up protection required 516.4_2.3 - devices, selection and erection of Sec537 - electrode water hcaters and boile$ 554.1.2 - e erge[cy switclring otf Sec 465 - functional Sec 461 - tirndamental priDciples for 132.14 & 15 - generating set. standby 5 51.6. l '7I4.537.2.t.201 - highway power supplies - instantaneous uatel heaters/boilers 554.3.3 & 4 main switch for installalion lnechanical n'tainterlance. lbr
462.1.201
ofcircuits
463.
Sec 464 r
.l
overvollagc due to. protection
against
prohibited irl PEN
corductor
Sec 441
1
46ll.2 543.4.',l
prohibited in prorcctive conductoE 543. j.1. l0 I rcmote, fbr mechanical maintenance 464:2 single pole. prohibired in neutral 131.14.2
l
5t0.3.3 step-Llp
translb tlers
55 s.
I.3
tc
-_
Syrnbols lol. diagrirms
-
Tents. cilcuits tbr 514.9.1 Tablc 55.3 Part 2
lunrraircs
used rn the Standard Systcm -
-
of
Appx 9
-
,111.3.1.2
-
Iclcconrmunication cables. bonding of Telcconrnlunioation circuits -
-
definitioll oi \blracc Baod I
etc. Tenns. eafihing and protectivc
-
-
aonductor opelating connaclions bet$ cen co[ducto]-s and !qLripment
currenl can'r inv capacitv enelosuaes constr-ucled during er!-ctrOrl
lault cur'r-cnl Drolection lloor and ceilins hcating svstcms
ol firc
plotection asnitist burns protecti! c conduclors r\ iring svstems marking. luninaircs
tlating oflanpholders
643.
automatic disconnectionolsupply coolpctcncy
643.7
522.t
elect cal separation for
).t
512. L5
-
421 l6 431.s.2 .201
-
6sl.s
-
conlpetent person. by
licqucncy
ol
plinciple requilelnent tbr
6,13.7.3.201
9.5.1.2 Table 55.3 559.5. r.205 55
Appx
3
.t.2
-
-
559. 714.
I(
iii)
I(
iv)
Sec 442 527
.2.t.t
P.t1t 2
Pan
clrcuses
643.7.1
-
714.514.12.202 Part 2
Sec 740 Sec 704 S".c 7l I
Paft 2
643.2.1 Sec 6,14 Appr 6
Appx 2 lten1 7 4i0.3 434.5.2
Thennal effects. prote!^tion against -
2
emporalJ c,lectrical illstallations at t'airgroLulds. amusenlent palks,
constrrlction sites lbr exhibitions. shows and stands i. :nrporar'y olen oltaee. delinitiotr
64i.1
643.10 r'ing linal circuit continuity test ceftillcates
Tlreah-es. etc.. installations ill ThLrrnal el}'ccts offault cu[ent
Tenipomry elccffical irstallation. I
643.2.1( i)
643.8
labcl stating nlaxil]lun load
-
I 35.1 651.1
643.6
Ternporarv -
delinition
Scc 652
nolices oo 514.12 recommelldaiion lbr. f'undalnental
422.1.2
culTent
341.1 Fig 721
Prospcctive fault curreot prctective conductors. contiDuity repeat. at'ier rectifi raliotl ol fault residual cuffent devices
121
rlclirition
6.13.5.1
polarity
suftircc. ofequipnlcnt
-
641.l0
522.t
103.5t2.2.
o\ cr\'ollages- proteclioD oflow \oltagc irlslallations against seaiing arilngenlents. fi re baniers ilr.!lclurc. defi Ditiotl supply unit -
40.6 643.3.2 7
543.1.3
s0unas
lcstoon lighring. excluded
.)
643.3 643.4 I hap 65 652.2
-
Sec 422 Sec 423
,123.1
-
613.1
643.7.3 643.4.1
rcsistance SELV and PELV peliodic allel-llalivc arrangclnents assessment lbl. nlairtainability
rise i0 circuit condnctors. effect on resistallcc
I
7l t.6
fairgrounds FELV functional insulation non-conducting lloors al1d walls
523.1
53 .424
134.2. 64 t.6
cxhibitions. tempolary installations
PatI2
'7
t0
643.2 Paft 2
earth elechode resislance eafih thult loop impedarlce
Appx 8 sec 2
lloor-rvanrrrng cables 5 5.1.4.,1 or efcurrenl prolcclion 430.3 prccaulion5. \\ here pal.ticular risk
-
641.5
definition
433.1.203
522.2.201 526.21v) 526.4 Scc 523
Sec 6,13 132. r2(ii)
assernblies
conductors
linriting clcr iccs. licaters fot liquids 554
Fig 2.I
continuity ofring final circuit
Appx 4 sec 2. I clelinition
I
614.5 651.5 continuity ol protective conductors 643.2
inlcrlerencc. pre\ention of electrical 528.2 Note I sesrei:ntion fiom other ci|cuirs 528.2 Note 2
-
I
Sec 526
accessibiiity olequiprnenr tbl additions and alrerations to installations
Part 2
applicabrlityofdleRegulationsto ll0.l.3(vi) Tempcrature ambient buried cables busbar trunkire svstems cables aud collductors
ol
Testing -
T rrlctal]ic shcalh ot'
708.52 r.7.I
Tenninations of cables. conductors,
conductor. illustlation
Parl ) 312.2
dcfinition typcs
708.1
burns file caused by equipment
fire. whcrc particular risks of- equipnlent rcquirelrents
-
escaPc routes
1ll.l Chap 42 Sec 423 Sec 421 Sec 422 422.1
422.2
locations constlucted of conlbustiblc
-
materials
422.4
fire plopagating stllictlres 422.s of particular significancc 422.6 \a ith fire isks dLle to proccssed or stored malelials 422.3 fhemral insulation. cables in 523.9 Themal rcsislance of soil 523.3
I
Tilerllal
slrcsses trn
ca hing
Transient ovc-rvoltaocs
Tripler hanlronics. defi[itiofl free,rlro
Hor nni( cuttv
412.4
Appx '[imc dclay - elec!odc $,ater heater-oI boiler ploteciorr
lbl
l)
\c on neL:
i
I
itrl
I
l
-
-
554.1.4
560.,1 devices 145.1 .)
hl tc s
TN systenl - conrroctionofcxposcd'co ductivePdrts in - defirlitiorl dc\iccs lor f'ault protection
312.2.1
4l t.1.2
Pafi2 411.4.5
-
exhibitions
-
tairyroulds
110.4|.4
isolatiou arrd switching olrlcuual
16t.2 5l1.2.1
1t | .411 .4
detinition PEN conduclors prohibited lbr aglcuitural ard
ho(iculural pienrises
defillitiorl
cxplarutory Dotes on isolalioD aud switohing ofneuhal TN S systcrr - conlrcction of installatioll to earth - detinition - explanatory notes on - iscrlatiol and swirching ofncutml
fool, lbr
-
alee
aki)
2
543.4
-
521.2.t 4I 3.3.5
sealing at flooN, etc.
insulating, for'elect cal separation
pafiitions in protective colductor's lblmed by sclcction of socket-outlets iD
corld ctor
-
542.)..2.2 Pafi 2 Fig 1.9
16t.2 542.t.2.1 Pafl 2 Fig 3.8
46t.2
-
oi ()1'
511.3.4.201
542.t.2.3
dcfinition
Part 2 411.5.2
devices for fault protection
disconnection tilnes fbr
41t.3.2.)
eafihing resistance reqLrircnleots
41 1.5
RCDS
411 .5.3
t4.4lt
prrls
714.1|.2.201 412.2.1.1(ii) Patl 2
-
Sec 555 Scc 442
10.2(ii)
536.4.2.3 536.4.3.2
4\
.',7
.4
433.3.3(iii) 413.1.1(i0
4ll.1.4 41
5l L3.5.3 312.) 4t2.2.t.1
522.11.1
Ulrder$ound cables - caravan/ter1t pitch supplies installalion
-
prefened
curent-cafl ying capacity
L8.4
414.3(i)
108.s21.1.2 108.s2t.7.1 433.1.203 523.3
Appx 4
lbblc 4D4A Tablc 4E4A Table 4H,lA
.2.20),
inslLlation of cquiprDc t Total selectivity, delinition Traction equipruert, r'ailway, thc Regulalions not applicable to Transt'er switching equipneit - back-up plotectlo0 ol - o'ielload proteclion of Tmnslor0]ors rDh not t(n F'ELV - current. omission 0foverload ptotection - tor electr-ical scparatiol - f'or FELV syslem - reduced lorv voltagc circuJts - safely isolalillg. to] SELV a d PELV systclDs
r
5422.) &4 Fig 3.10
U
4t2.2.2.3 416.2.,1(iii) 416.2.4(t)
outdoor luminaircs siieel tumiture. access to live
ol
41t.5.3
eafihing resistaice var jations explanatorJ notes oll fa lt protectiolr
Type{ested equipment. Class Il
-
'7
]bul
&9
4n.5.1
702.55.i
intcranediate barier. re[roval crpening enclosurcs
3
Ultraviolet radi.rtion, wirilrg systeus
lburrtains, nlechanical proteclioD, insulating barrier', removal
528.1 543.2.5.',l 521.6 530.4.1 54 3.2.7
connection ofinstallatiol to Earlh
Tlpcs of systern earthing
542.4.2
lelnoval 0f
&
31).2.2 41 1.5 automatic discon[cction ir] connection olcxposed-conductive-
and
ol RCDS disconlcctiol ol main eathi]rg
s.rl.r(:tion an(l erectiorr
fre
522.3
52',t.2.2 527.1.5
542.1.3.1(i)
scxings 5l3.l.i
adjustrDcnt
Transiomler substation
510.4.1
4) 1.3.2.4
-i(d,r,i -
adjustn)cnt ol'o\crcurrcul
Sec 521
equiprrent fixcd on or in exposed to water oL high hunidity lire bal iels il flarnc propagation rcquirenrcnts
parts in
705.41 1.4
TN-C-S sysle l - coDrlection of irNtallatiolr eanhing tcrmilal to supply neutial
-
Part
itl
cables and coDduclors
Part 2 Pan 2
TT system -
-
l-N-(l syslem -
-
ts) delidtion
Tmnking (foi cables). TrLlnkil1g systcl11s -
3r3.2
salety serrices srpplies
- tbr u clenoltago plotcctivc 'l-ime\. disco nectiorl r,rc
Sec 443
Transportable ullits ree Mt)bile uDits
Iil1le/current character'islic\. overcurlent dc\iccs
-
331.1(i)
i,12.1.3.1(ii)
aIIaDgemeDls TlluDdel stol l)ls -rcd 0\ er\ oltagaplote0tio1r agail]st
Table:U4A
-
depth, aglicuJtural installations depth, gereml fairgrounds
-
ilstallation methods
-
marinas, distribution
705.522 522.8. i0 740.521.1 Appx 4 Table 4A2 (Nos 70.
72.'.|3) marking
circ[its tbr
ol
709.521.1.7 522. iJ.10
740.521 .t
-
mting factors for soil themal rcsistivity type, protection aDd idcntiiicatiorl UndeNoltage, assessDclt ol Undervoltage, protcctio11 agairlst
Appx 4
Appx 4 sec 2.2 522.8.10
l3
r.
r(ii)
Sec 445 Sec 5.15
Underwater lumillaires, swilxring
pools
702.55.2
Urintenuptiblc po\\,er supplics (UPS) 560.6.12 Unwanted tripping of RC
Ds
3 14.
1(iv)
531 .3.2
v Values
ofk
Table 43.1 Tables 54.2 to 6
Variation of installation conditions along route 523.8 Vamish. generall-u" not as insulation 416.1Note Vehicle. electric. charging installations see Electric rehicle
-
Water appliances producing heate$ and boilels. electrode
-
-
certification for examples
Palt 2 t34.2
bands. definitions drop -- busbar trunking systems
-
extra-lo\\ \oltage lighting limits porvenrack srstems tabulated r alues. for cables
exceeding
lor
r oltage.
8
-
Drairl bonding
-
public. prohibited as eafth
-
wjring system in proximity to
watcr
543.2.6
heaters ofinstallation
554.3.2 411.3.1.2
of
'1
512.2.6 528.3
514.t.2 52).3
Sec 521
Part 2
agriculturalpremiscs
105.52. 52.2_.t
-
ambient temperature fol bu ed in floor camvan parks calavans
-
condensation in construciion sites
522.8.7
708.52t.7 '721.5)1
12t.5)2 522.3.) '704.s2
corrosive or polluting substances, exposed to damage by launa damage by- flom or mould
522.10
harmonization high see High rolrage
Appx 2 sec l5
erectiou of
522.8
escape rourcs in
limit -
-
ceiling roses and Iampholders separated circuits deflnitlon
Pafi 2
reduced nominal assessmenl
,111.8
-
deflnition exceeding
rnechanical stresscs
ol
313.1(i)
-
eafih.
waming of ranges covcrcd b) lhe Regulations rcduced lo$ \,ohage circrits SELV and PELV
suitabilit) oieqLriprnent for
reduced, delinition
5 1,1.
r0.l
1r0.1.2(i). (ii) 41 1.8. L2 1)
1.2\i\
5r
2.l.l
Paft 2
ripple-free. definition
410.1.1 segregation ofdifferent voltages 515.2 within assemblies tolerances sec./er,,ition oJ Lbltage,
Pafi 2
Voltage disturbances. proteciion against
mctalwork of. as protective conductol'
Pafi 2
lio \'to
ChaP,14
-
lrlobilc
5D.9
7t |.52 710.52 702.522.23 521.1 to 3 Sec 529 709.521.1 522.6 to 8 522.15 543.2 '717.52
Lrnits
pcnetration of load-bearing element 522.8.14 presencc ofdust safcty seNices
560.Ii
saLrnas
sealing of pcnetrations sclcction and election solar. etc. radiation. precautions irgainst
suppon of
\'ibratioo water in Worknranship. erection by skillcd or instructcd persons
x
Walls -
\-r'a1 equiprrrerrt. R( D pr'otcctic,n in Crolrp 2 iledical
703.52 527.2 Chap 52 522.11
521.10.202 '702.5)
suirrming pools
w 512.6.202 to 204 cables concealed in fire resistant. cables passing through527.l .1r E.1.5 insnlatins. resistancc oi
522.5
buildi[gs
exhibitions lairgrounds. etc. tbrultairls. additional reqLliremcnts installatioD methods rnaintainability lnarinas
559.5.1.201 413.3.2
low -
-
3
109-512.2.1.1
Wiring systenr, definition Vy'iril'rg systems -
applicability
nomital, nole
-
&
for instantancous
6.4
111.4.5
-
551.2
701.55(x)
I10. r .2(ii) Part 2
-
-.
as bonding bonded n-rctal.
-
7I 5.525 Sec 525
Appx Appx
conductols
-
-
Appx 8
,1 sec
554.1
ofthe Regularions to extra-lo\\. de6nition for insulation resistance testillg
-
-
rrarinas.selectionofequipment
424.1
pipcs -
clcction
Part 2 Sec 525
Appx
clcmcnls bathrooms
seryice. main bonding to wiring systerns exposed to Weight.iee Mass wirirlg nuterials. selection and
522.10 705.522.10
5)2.7
-
in
-
Appx 6
721.522.1.t
type
electrodes
643.9
wiring slstems subject to
-
-
Appx 6
camvan wiring
523.9
544.t.2
Voltage -
-
ha\ing ilnmelsed heati[g
6,1
Vibration -
-
-
Sec 6,14
phase sequence schedule tbr dornestic and similar Vermirl. \\ iring s!'stern exposed to
in
hot
ol items requiring
inspection. lists of
-
-
705.560.6
4)2.5
Chap
tlrcnnally ilsulating, cables
Waming notices see Notices - Wdnli]19
Yelticles ;ce ntotor vehicles Ventilation - livestock. lile support of - systern. forced Verificatiorl. dellnitiorl Verification. initial -
socket-outlets on. urou[ting height 553.].6
locations
522..7
522.3 134.1.1
7l0.4ll.4lo
6
Y No entries.
Z Zones bathrooms, showels
-
10t.32 Fig 701.1
Fig 701.2
-
556
cables in walls and partitions
fountains
-
saunas
-
swimning pools
522.6.202 702.32 Fig 702.4 703.32
Fig 703
-
102.32 Figs 702.1-3