Substation Spec

2 Volume

EQUIPMENT SPECIFICATIONS Damodar Valley Corporation, PSR Section, Electricity Dept.

Tender Specification E DCON / EHV/BURNPUR EXTN./220 KV

1

DAMODAR VALLEY CORPORATION

Tender specification EDCON/EHV/Burnpur Extn. /220KV PSR Section, Electricity Department DVC TOWERS VIP Road Kolkata - 700054 Phone 033 2355 6043 • Fax 033 2355 9618

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

2

Table of Contents SPECIFICATION FOR CONTROL AND RELAY PANELS ..........................................................3 SPECIFICATION FOR METERING EQUIPMENT.....................................................................26 SPECIFICATION FOR CIRCUIT BREAKERS ...........................................................................38 SPECIFICATION FOR ISOLATORS..........................................................................................50 SPECIFICATION FOR INSTRUMENT TRANSFORMERS .......................................................59 SPECIFICATION FOR LIGHTNING ARRESTERS....................................................................68 SPECIFICATION FOR LT (FRLS) CABLES ..............................................................................72 SPECIFICATION FOR ALUMINIUM TUBES .............................................................................79 SPECIFICATION FOR CONDUCTOR ......................................................................................83 SPECIFICATION FOR CONNECTOR .......................................................................................88 SPECIFICATION FOR HARDWARE AND ACCESSORIES......................................................92 SPECIFICATION FOR SOLID CORE POST INSULATORS ...................................................103 SPECIFICATION FOR DISC INSULATORS............................................................................107 SPECIFICATION FOR LIGHTING ...........................................................................................122 SPECIFICATION FOR JUNCTION BOXES & OUTDOOR PANELS.......................................134 SPECIFICATION FOR SAFETY EQUIPMENT ........................................................................138

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

3

SPECIFICATION FOR CONTROL AND RELAY PANELS DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1

Scope

The specification covers the design, manufacture, assembly, testing at manufacturer’s works, packing and delivery of control and relay panels for 220KV/ 33KV substations.

2

Standards

Equipment covered by this specification shall conform to latest issues the following Standards: IS:1248

Direct Acting Indicating Analogue Instruments and their Accessories

IS:6236

Direct recording electrical measuring instruments.

IS:13703

Low voltage fuses.

IS:5578

Guide for Marking of insulated conductors.

IS:694 1100V.

PVC insulated cables for working voltages up to and including

IS:11353

Uniform system of marking and identification of conductors and apparatus terminals.

IS:3231

Electrical relays for power system protection.

IEEE C37.90

IEEE Standard for Relays and Relay Systems Associated with Electric Power Apparatus.

IEEE C37.90.1

IEEE Standard Surge Withstand Capability (SWC) Tests for Protective Relays and Relay Systems Associated with Electric Power Apparatus.

IEEE C37.90.2

Electrostatic Discharge Tests for Protective Relays

IEC 60688

Electrical Measuring Transducers for converting a.c electrical quantities to analogue or digital signals.

IEC 60255-5

Electrical Relays- Part 5 : Insulation co-ordination for measuring relays and protection equipments-Requirements and tests

IEC 60255-6

Electrical Relays-Part 6: Measuring Relays and protection equipments.

IEC 60255-22-2

Electrical disturbance tests for measuring relays and protection equipment, Electrostatic Discharge Tests

IEC 60255-22-3

Electrical disturbance tests for measuring relays and protection equipment, Radiated Electromagnetic Field Disturbance Tests

IEC 60255-22-4

Electrical disturbance tests for measuring relays and protection

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

Electrical

Measuring

4

equipment, Fast Transient/burst immunity Tests IEC 60255-22-6

Electrical disturbance tests for measuring relays and protection equipment - Immunity to conducted disturbances induced by radio frequency fields

IEC 60255-25

Electrical relays - Part 25 : Electromagnetic emission tests for measuring relays and protection equipment

IEC 61850

Communication networks and Systems in Sub-station – all relevant latest versions and editions.

Where the equipment offered conforms to any other standard, the salient points of difference between the standards adopted and IEC recommendation shall be clearly indicated and the English version of the proposed standard shall be furnished.

3

Function

Control : The panels shall be used for switching in and out transmission lines, power and auto transformers, feeders with adequate indications depicting the status of each equipment. Protection : The panels shall also provide adequate relays for protection of transmission lines, power and auto transformers, feeders as detailed in section 5.2. Protection Transfer : For 220 KV 3-bus and 132 KV 2-bus layouts, there are no provision of CTs in the Bus Coupler as the CTs are located on the Line side of the bays. In the case of 33 KV 2-bus layout, for the transformer bays only, CTs are located on the transformer side. For 33KV feeders bays, CTs are located on the Main bus side. For transfer of 33 KV feeder bays one set of CTs are located in the 33 KV Bus Coupler. In the event of transfer of a 220 KV / 132 KV Line / Transformer bay to the bus coupler bay, all protective commands are to be diverted to the bus coupler breaker through a protection transfer switch. During transition it should supervise both the breakers. Necessary mechanical interlock (key operated) shall be provided so as allow the diversion of one bay to Bus Coupler at a time. Interlocks

4

: Adequate interlocks to be ensured between breaker and isolators.

Construction

The panels shall be of Duplex or Simplex type as indicated in the Specific Requirements. The panels shall be sheet steel enclosed, dust and vermin proof with minimum degree of protection not less than IP-31. The panels shall be floor mounting freestanding type mounted on a supporting structure so as to form a rigid enclosure suitable for the application. The panels shall be fabricated out of CRCA sheet steel of minimum 3 mm thickness for the front and back covers, doors and load bearing members and 2 mm for the rest. All doors and openings shall be provided with neoprene gaskets. The panel shall be provided with integral base frame. The integral base frame of panels shall be suitable for directly bolting with the help of foundation bolts and shall also be suitable for tack welding to the control room floor embedded insert plate/ flat/ channel. Amply dimensioned oblong holes shall be provided at the bottom of all panels for bolting on to the embedded insert channel.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

5 The height of the panels shall not exceed 2400 mm and the bottom of the panels shall have a 100 mm thick plate all around. Cable entry shall be from the bottom unless specified otherwise. A suitable removable undrilled gland plate shall be provided for cable entry. Suitable compression type cable glands as required for cable termination in the control panel shall be supplied. The control panels shall be matched with other panels in dimension and colour wherever specified. Simplex type panels shall be with equipment mounted on the vertical front and access to wiring from rear. Door at the rear shall be provided with handles and locking facility. Duplex panel shall consist of a front and a rear panel connected back to back with a walkway in the central corridor having width not less than 800 mm. There shall be complete access through the corridor to the terminal blocks, internal wiring and components mounted on the panel. Separate cable entries shall be provided for front and rear panels. Interconnection between front and rear panels shall be by inter-panel wiring (through the corridor) at the top of the inside of the panel. Adequately sized hinged type access doors shall be provided at both ends complete with door handles, lock and latching facility.

4.1

Component mounting

In case of Simplex Panels, all controls, indications, meters, annunciations, mimic diagram, protective relays having operations indicator and lock out relays requiring hand reset shall be mounted on panel front. However auxiliary relays can be mounted inside, if the space on panel front is limited. All components shall be neatly arranged in a matching manner. In case of duplex panels, controls, indications, meters, annunciations and mimic diagram shall be mounted on the front panel and relays shall be mounted on the rear panel. All equipment mounted on front/rear panels shall be flush mounting type. All meters/ components shall be suitable for vertical/horizontal mounting. All control gear, switches, push buttons etc. shall be within easy reach for proper operations. The meters shall be so located as to enable easy observations of readings. Checking and removal of individual components shall be possible without disturbing the adjacent equipment. It should be possible to test all the protective relays ‘in-situ’. The internally mounted components, auxiliary equipment such as transducers, interposing CTs etc. shall be mounted in such a way as to be readily accessible without impeding the access to internal wiring and other components. All control and supply cables will be laid in distributing trenches running under the control panel. Necessary drawing showing cable entry positions and foundation bolt locations shall have to be supplied by the successful Bidders. The control panels shall be supplied complete with channel base grouting bolts, nuts, washers etc.

4.2

Wiring

The wires shall conform IS:694. All wiring shall be done with PVC insulated 1100V grade, single core multi-strand (minimum 3 strands) annealed copper conductors. The wires shall be flame proof and vermin proof. The minimum size for different circuits shall not be less than those as specified below : 1)

Current Transformer Circuit

: 1 X 2.5 sq. mm. Copper

2)

Voltage Transformer Circuit

: 1 X 1.5 sq. mm. Copper

3)

Other Circuit including Control wires : 1 X 1.5 sq. mm. Copper for fuse rating of 10 Amps or less.

Each wire shall be identified at both ends with wire numbers by means of PVC ferrules.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

6

Ferruling of wires shall be as per relevant IS. All control wiring shall be enclosed in plastic channels. The terminal blocks shall be located so as to ensure easy access. Split type terminal blocks shall be provided for all CT terminals. The terminals screws shall be of the Washer type and long enough for connecting following type conductor on each side. Each terminal block shall be capable of terminating the following no. of wires: CT circuits PT/CVT circuits AC/DC supply circuits All other circuits

2 nos 10 mm sq. copper 2 nos 2.5 mm sq. copper 2 nos 2.5 mm sq. copper 2 nos 2.5 mm sq. copper

Each terminal block shall be provided with a wire-marking strip and shall be shrouded by easily removable shrouds moulded of transparent dielectric material. Provision shall be made on each pillar for holding 20% extra connections both for incoming and outgoing. The terminal blocks shall be suitable for 660 V,10 A rating. There shall be a minimum clearance of 250 mm between the front row of terminal block and the associated cable gland plate on panel side wall. The clearance between two rows of terminals block edges shall be a minimum of 150 mm. All inter-panel wiring within each shipping section shall be the vendor’s responsibility. Wiring between panels shall be routed through PVC sleeves. For wiring between shipping section, vendor shall provide terminal blocks on adjacent shipping sections and supply suitable jumpering wires.

4.3

Earthing

A continuous 25mm X 3mm copper (tinned) earth bus shall be provided along the full length of the panels. Suitable arrangement shall be provided at the two ends for connection to the plant grounding system. Each panel and the equipment mounted on each panel shall be securely connected to the grounding bus. For this purpose the ground wire shall be looped from equipment to equipment and both ends of the ground wire shall be connected to the ground bus. All doors and movable parts shall be connected to the ground bus with flexible copper connections. Current free metallic parts or metallic bodies of equipment shall be earthed with soft drawn single conductor bare copper. Tail connection shall have minimum area of 16 sq. mm and main connection 60 sq. mm. These wires shall be connected by Ross-Courtney terminals and clamp junctions. Soldered connections shall not be employed. The main earth connection for each panel shall be brought out to terminals for connection to the station earthing system.

4.4

Illumination & Space heaters

Incandescent or fluorescent lamps working on 240V AC, operated by door switches shall be provided for internal panel illumination. A 240V, single phase, 5A, 3 pin socket shall be provided in the panel corridor or interior of each cubicle with on-off switch for connection of hand lamps. This socket shall be metal clad type with a spring loaded flap. Panel space heaters shall operate on 240 V±10% AC and shall be supplied complete with onoff switch, fuse and thermostat. A common thermostat shall be provided for the entire panel. The thermostat shall maintain the internal temperature above the ambient temperature to prevent moisture condensation. The watt loss per unit surface of the heaters shall be low enough to keep surface temperature well below visible heat.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

7

4.5 Painting All metal surfaces shall be thoroughly cleaned and degreased to remove mill scale, rust, grease and dirt. Fabricated structure shall be pickled and then rinsed to remove any trace of acid. The under surface shall be prepared by applying a coat of phosphate paint and a coat of yellow zinc chromate primer. The under surface shall be made free from all imperfections before undertaking painting coat. After preparation of the under surface, the relay and control panel shall be spray painted with two coats of final epoxy paint or shall be powder coated. Colour shade of final paint shall be 631 (light grey) as per IS:5 unless otherwise specified. The spray painted finished panels shall be dried in stoving oven in dust free atmosphere. Panel finish shall be free from imperfections like pin holes, run-off paint etc. All hardware parts shall be cadmium plated or suitably treated to prevent rust and corrosion. If these parts are moving elements these must be greased.

4.6

Mimic diagrams

Mimic diagram shall be provided on all panels. The mimic diagram shall be screwed on to the panels and shall be made of anodised aluminium or plastic of approved fast colour. The mimic shall be 10mm wide for horizontal run and 5mm wide for vertical run. If semaphore indicators are used for indicating isolator position, they shall be automatic type and shall be mounted in the mimic in such a way that isolator closed position shall complete the continuity of the mimic. Alternatively red and green lamps may be used for indicating the Closed and Open position of the isolators. In such cases the isolator control switches shall be placed at appropriate positions in the mimic diagram. The mimic diagram shall also incorporate lamps and control switches for all the breakers. Alternatively discrepancy switches with in-built semaphore and position indication lamps may be provided for breaker control/indication. The discrepancy lamp shall perform the following functions: • The breaker on-off control shall be through this switch. • The lamp will remain steady when the semaphore position corresponds with the breaker position. • The lamp will flicker if the semaphore position does not correspond with the breaker position. The colour code for the various voltages shall be as follows: • 220KV - Golden Brown to shade 414 of IS : 5. • 132 KV - Signal Red to shade 537 of IS : 5. • 33KV - Brilliant Green to shade 221 of IS : 5. • Earth – Black

5 5.1

Instrumentation Control

5.1.1 Bay Control Units The Bay Control Units (BCU) shall have, but not limited to, the following in-built functions : • Mimic to display graphically the bay configuration, status, analogue measurands, alarms and bay level control. •

Status supervision of switchyard equipment.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

8 •

Switching of equipment depending on conditions such as interlocking, synchrocheck, control mode or external status condition.

•

Interlocking function to prevent unsafe operation of equipment. Interlocking shall be implemented through the configuration software of the BCU. Bypass capability shall be provided at appropriate security level for maintenance or emergency conditions.

•

Analogue measurements of bay voltage, current, frequency, MW and MVar. These measurements shall not require the use of any intermediate transducers.

•

Event and Alarm handling with a resolution and time tagging of 1ms and onward transmission to operator’s workstation. Generation of commands for accepting and reseting annunciations in the conventional annunciation units.

•

Synchronisation check feature to determine difference between the amplitudes, phase angles and frequencies of two voltage vectors. Checks shall be provided to detect a dead line -live bus or live line-dead bus . The connection between the BCU and Protection units for achieving the auto-reclose function shall be achieved with the communication LAN at the bay level.

•

Features such as pole discrepancy detection and trip circuit supervision shall be available.

5.1.2 Indicating Instruments All instruments shall be of switchboard type, back connected, flush mounted, dust proof and tropicalised. The instruments shall be of digital or analogue type. The analogue indicating meters shall be of size 96 X 96 sq.mm. These instruments shall have a scale covering 0-240o and a minimum accuracy class of 0.5. Zero adjustment for pointers must be accessible from the instrument front. Digital panel meters may be used provided they conform to relevant national and international standards. All auxiliary equipment such as transducers, interposing CT/PT, shunts etc that may be required shall be included in the scope of supply. Frequency meter shall preferably be of digital type. Alternatively they may be of analogue type calibrated for 45-0-55 Hz.

5.1.3

Indicating lamps

Super bright LEDs shall be the preferred means for indication. The LEDs shall be suitable for 220 ±10% volt DC supply.Lamps shall be provided with screwed translucent lamp covers to diffuse light. The lamp covers shall preferably be unbreakable, moulded, heat resistant material and shall be provided with chromium plated bezels. The following color scheme shall be followed for indicating Lamps : SIGNALS FOR

COLOUR

Circuit breaker closed Circuit breaker open Circuit breaker auto trip Circuit breaker trip circuit healthy Circuit breaker spring charged Isolator Closed Isolator Open Transmission Line Potential ( For 220 KV and 132 KV only) Carrier protection in service ( For 220 KV and 132 KV only) Auto Reclose in service ( For 220 KV and 132 KV only) CB drive ready Main Protection Healthy ( For 220 KV and 132 KV only) Back up Protection Healthy ( For 220 KV and 132 KV only)

Red Green Amber White Blue Red Green White White White White White White

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

9 Protection Healthy ( For Transformer and 33 KV Feeder) Bus Potential indication ( All Phases, for 220 KV,132 KV and 33 KV)

White White

Colour of lenses for other functions would be indicated during detailed design stage.

5.1.4

Control Switches

The control switches shall be of rotary back connected type, having cam operated contact mechanism. Contact mechanism stages shall be protected by transparent noninflammable cover of moulded dielectric material. The number way indicated is approximate one and will be finalised after detailed design keeping sufficient spare (at least 20%).

Type of Switch

Specific Requirement

Circuit breaker Control Switch

1) 3 position with spring return to ’Neutral’ from both ’ Close’ and ’Trip’ positions. 2) Shall have pistol grip handles and the handle shall turn clockwise for closing operations and anticlockwise for tripping operations. 3) Red and Green escutcheon plates shall be provided to indicate ”ON” and ”OFF” operations of the switch even when the handle has returned to the normal position after the operation has been carried out. 4) The control springs shall be strong enough to prevent any inadvertent operation due to light touch. 5) The switches would be provided with lost motion and sequence device. 6) The number of ways shall be such as to leave at least 20% spare contacts of each type.

Isolator Control Switch

1) 3 position pistol grip type with spring return to neutral and lost motion device. 2) Escutcheon plates shall be provided

Protection Transfer Switch (for 33KV also)

1) Stay put ganged type with 20% spare contacts but at least 48 ways spade handled (lockable) 2) Key to be disengaged only in normal position.

Auto Reclose Cut Off Switch

4 position, oval head, stay put type having Single Phase, Single and Three Phase, Three Phase and Non Auto positions.

Carrier Cut Off Switch

2 position (On and Off) oval head, stay put type

Bus PT selector switch

3 position, oval head, stay put type

Parameter Selection Switch

4 position, oval head, stay put type

The rating of all switches shall not be less than 10 amps continuous and 150 amps momentary direct current.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

10

5.1.5

Annunciation Unit

Solid state type alarm annunciation system shall be provided in each control board by means of visual and audible alarm in order to draw the attention of the operator to the abnormal operating conditions or the operation of some protective devices. The annunciation equipment shall be suitable for operation on the voltages specified. The details of inscriptions for the window block for different panels will be intimated at the time of approval of drawings. The annunciation shall be of visual and audible type. The visual annunciation shall be provided by annunciation facia flush mounted on the top of the control panels. The audible alarm shall be provided by alarm buzzer or bell. Preferably sound of bells/buzzer shall be matched with existing sound of 220 KV system. The annunciation facia shall be provided with translucent plastic window for alarm point with minimum size of 35 mm x 50 mm. The facia plates shall be engraved in black lettering with respective inscription which will be approved by the Purchaser. Alarm inscriptions shall be engraved on each window in not more than three lines and size of the lettering shall not be less than 5 mm. Each annunciation window shall be provided with LEDs in parallel to provide safety against lamp failure. Long life LED shall be used. The lamp circuit shall include series resistor of adequate rating. The cover plate of the facia windows shall be flush with the panel and shall be capable of easy removal to facilitate replacement of LED. The transparency of cover plates and wattage of the lamps provided in the facia windows shall be adequate to ensure clear visibility of the inscriptions in the control room having high illumination intensity (500 Lux), from the location of the Operator’s desk. TRIP AND NON-TRIP facia shall be differentiated. ALL TRIP facia shall have red color and all NON-TRIP facia shall have white color. Sequence of operation of the annunciator shall be as follow : Alarm Condition

Fault Contact

Visual Ann.

Audible Ann.

Normal Abnormal Accept PB pressed

Open Close Close Open Close open Open

Off Flashing Steady On Steady On On Off Steady on

Off On Off Off On Off Off

Reset PB Lamp test

Visual and audible annunciation for the failure of DC supply to the annunciation system shall also be provided and this annunciation shall operate on 230 Volts AC supply with separate fuses. On failure of the power supply to the annunciation system for more than 2 or 3 seconds (adjustable), a facia shall light up and a bell shall sound. A separate push button shall be provided for the cancellation of this audible alarm alone but the facia window shall remain steadily lighted till the supply to the annunciation system is restored. The sound of the audible alarm (bell/buzzer) provided for this annunciation shall be different from the audible alarm provided for the annunciation system. A separate voltage check relay shall be provided to monitor the failure of AC supply (230 V AC) to the scheme mentioned in the above Clause. If the failure of supply exists for more than 2 or 3 seconds this relay shall initiate visual and audible annunciation (bell/ horn) which shall have distinctly separate tone than that of DC fail. The annunciation system described above shall meet the following additional requirements: • The annunciation system shall be capable of catering to at least 30 simultaneous signals at a time. • One self-resetting push button shall be provided on each panel for testing the facia

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

11 window lamps. Push buttons for testing flasher and audible alarm circuit of annunciation system and for testing the annunciation supply failure monitoring circuit shall also be provided. These testing circuits shall be so connected that when test is being done it shall not prevent the registering of any new annunciation that may land during the test. One set each of the following push buttons shall be provided on each panel as shown in the front view drawing: • Reset push button for annunciation system. • Accept push button for annunciation system. • Test push button to check the healthiness of the annunciation system. The annunciation shall be repetitive type and shall be capable of registering the fleeting signals. Auxiliary relay for annunciation system shall have adequate auxiliary potential free contacts for use in event logger. The annunciation shall be suitable for operation with normally open fault contacts which closes on the occurrence of a fault. For fault contacts which open on a fault, it shall be possible at site to change annunciations from ‘close to fault’ to ‘open to fault’ and vice versa. Special precaution shall be taken by Contractor to ensure that spurious alarm condition does not appear due to influence of external electromagnetic/electrostatic interference on the annunciation wiring and switching disturbances from the neighbouring circuits within the panels.

5.1.6 Transducers Transducers shall in general conform to IEC 60688. The transducer characteristics shall be linear throughout the range of measurement. The transducer output shall be load independent and suitable for load resistance of 1000-1500 ohms. The transducer shall derive its auxiliary supply from the panel DC source.The voltage, frequency and current transducers shall have an output of 4-20 mA and the active and reactive power transducers shall have an output of 4-12-20 mA. Voltage and Current transducers shall be of accuracy class 1.0 or better, Watt/ Var transducers shall be of accuracy class 0.5 of better, and frequency transducers shall be of accuracy class 0.2 or better. Galvanic isolation shall be provided between input and output circuits. The transducer shall have a response time of less than 1 second and its output AC ripple shall be less than 1%.

5.1.7

Name and identity Plates

All instruments, relays and other electrical devices mounted on the control panel shall be provided with identity plates bearing the Manufacturer’s name, Serial number, Model number and the electrical rating data. Ten (10) mm wide plastic plates bearing suitable identification marks shall be fixed in the interior of the switchboard, at the test blocks, at the fuse blocks and at the cable terminals. Similar plates shall be fixed to indicate functions of control switches, push buttons, indicating lamps, relays and other equipment not incorporated in the mimic diagram etc. Suitable identification marks shall be provided for other instruments as well. Fifty (50) mm brass or plastic plates bearing respective circuit designation (which will be furnished later) etched in 30 mm letters and mounted suitably on the top of the front side and back side of each panel shall be supplied and fixed in such a way that these can be removed and refitted when desired.

5.1.8

Synchronising Trolley

Wherever called for in the approved specification, swinging type synchronising panel/ synchronising trolley complete with running and incoming voltmeters, running and incoming frequency meters, syncroscope, synchronising check and guard relays, synchronising switches, lamps etc shall be provided. Automatic synchronising device with

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

12 inputs to speed and voltage control shall be provided if additionally asked for. The swing type panel shall be mounted on the main panel with hinges and shall be so located as to enable easy operation of all breakers provided with synchronisation facility. Synchronisation trolley shall be provided on wheels with multipin plug and flexible lead. Sockets shall be provided on main panel wherever required for synchronising.

5.2

Protection

(Note: IED : Intelligent Electronic Device) Description / Configuration

Feature

220KV Type-I

Type-II

5.2.1 Line Protection 5.2.1.1 Main Protection IED(s)

5.2.1.2 Backup

Distance ProtectionTwo IEDs for each Line. 1) Main-I 2) Main-II – of make other than Main-I protection IED. Not required

Protection IED (Type-III)

Pilot Wire Current Comparison Differential Protection – One IED for each end of the Line.

One Directional O/C and E/F IED for each Line/Line end (Type-III) of make other than Main Protection IED.

5.2.1.3 General Description (For all IEDs) Type –I Numerical, fully discriminative, 3 phase, 3 steps directional distance protection, nonswitched IED with 6 independent impedance measuring loops, for phase to phase, 3 Phase, double phase to Ground faults and single phase to ground faults. Type-II Numerical, fully discriminative, 3 phase Pilot wire current differential protection non-switched IED with 6 independent impedance measuring loops, for phase to phase, 3 Phase, double phase to Ground faults and single phase to ground faults. Type-III Numerical, fully discriminative, 3 phase directional over current and earth fault protection IED. 5.2.1.4 General Requirement (For all IED Types) The features described under this section shall conform by all the IEDs. 1 2 3

Construction Mounting Type

4

Measuring Unit

Modular Flush Mounted Back connected draw out type or plug in type modular cases, suitable for rack/panel mounting. For Draw out type, the provision of CT shorting shall be available when the IED is drawn out. Shall be able to measure true RMS values up to 10th harmonic with an accuracy of 0.1% under normal conditions. The metering accuracy shall be well within 0.2% for direct measurement. Measurement functions shall comprise of power system measurement, supervision and reporting to the local HMI, monitoring software and to station level (i.e. IEC 61850). Continuous monitoring of active power, reactive power, currents, voltages, frequency, power factor, detailed fault data etc. shall be present.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

13

Description / Configuration

Feature

220 KV Type-I

Type-II

Type-III

Accuracy class of the measuring unit should be equal to or better than class 0.5. Test blocks/Test Plugs for ‘in-situ’ testing of the IEDs shall be incorporated in the IEDs. Insertion of the Test Plug shall cause: 1) Shorting of CT Circuit 2) Opening of VT Circuit (Applicable for Types I and II only) 3) Opening of Tripping Path The line differential IEDs at both ends of the line shall be able to be tested from one end.

5

Test Block/Test Plug

6

I/O Device

¾ Adequate number of inputs/outputs (I/O) to comply with the I/O list indicated in this specification. These I/O shall be freely configurable. ¾ Shall be provided with one extra isolated I/O module, exclusively for Purchaser’s use.

7

Rating

8

Communicatio n Port

¾ Auxiliary Supply : 220 ± 20% V D.C ¾ Current coil : 1A/5A depending on relevant CT secondary current . The permissive thermal withstand(rms) on the current inputs shall be – a) 2 times of rated current – continuous. b) 100 times of rated current for 1 second. 1) Rear Ethernet port for station level communication (IEC 61850).

IEC 61850 Compatibility

2) RS 232/RS 485 /LAN port in the IED front for communication with Base computer/Laptop IEC-61850 compliant in all respect and interoperable with IEDs of other manufacturers.

9

10 Self Monitoring

Shall comprise of Self Monitoring Feature.

11 Display

Shall facilitate displaying of the system parameters without the need for any deciphering and changing the required parameters through its front panel. However, such changes should have a password access control.

12 IED Front Panel LED

Fixed and User configurable to allocate it for any critical fault / event at site. Indications for “Relay Healthy” and “Relay Faulty” shall be present. Number of User configurable LEDs shall be such that to accommodate at least the following eventsFor 220 KV Type-I For Type-II 1) R-Phase Trip 1) R-Phase Trip 2) Y-Phase Trip 2) Y-Phase Trip 3) B-Phase Trip 3) B-Phase Trip 4) Z1 operated 4) LBB operated 5) Z2 operated 5) Pilot Fail 6) Z3 operated 6) Power Swing 7) Backup Directional Protection operated Block 8) LBB operated 7) SOTF 9) VT fuse Fail operated 10) Power Swing Block 8) Auto Reclose 11) Carrier Protection Operated

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

14

Description / Configuration

Feature

220 KV Type-I

Type-II

Type-III

12) SOTF operated 13) Auto Reclosed For 220 KV TypeIII ( to be used with Type-II) 1) R-Phase Trip 2) Y-Phase Trip 3) B-Phase Trip 4) Backup Non Directional Protection operated 5) LBB operated 6) VT fuse Fail 7) Power Swing Block 8) SOTF operated

All the above configuration shall be changed as per site requirement. 13 Fault Data Download

Downloaded fault data shall be possible to save in ‘COMTRADE’ format from a remote location with playback facility of the downloaded waveform.

14 Distance to Fault Locator

i) The fault locater shall be microprocessor based ’On-line’ type. ii) It shall be suitable for breaker operating time of 2 cycles. iii) It shall have built-in display unit. The display shall be directly in percent of line length or kilometers with out requiring any further calculations with an accuracy of 3% or better for all type of faults and fault levels. The above accuracy shall not be impaired under the following conditions a) presence of remote end in feed b) predominant D.C. component in fault current c) high fault ARC resistance d) severe CVT transients. iv) It shall have facility for remote data transmission. v) It shall have mutual zero sequence compensation unit if fault locater is to be used on double circuit transmission line.

15 IRIG-B / equivalent Input

Shall be provided with time synchronising inputs (IRIG-B or equivalent) for receiving GPS UTC signal.

16 IED Case

Case of the IEDs shall be so constructed and arranged that any non-permanent deformation cannot prevent satisfactory operation of the IEDs.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

15

5.2.1.5 Specific Requirement 5.2.1.5-A Main IEDs 1 Type I Distance/Differentia Shall have Polygonal and circular characteristics (offset mho l Protection type). It should cover at least line sections completely with 20% in hand margin. The Characteristic should be compatible to the line length with provision for independent reactance setting, phase to phase fault and phase to earth fault resistance setting. The circular characteristic shall have the provision for Arc Resistance Compensation. i)

The IED shall operate at maximum fault current of 40 KA and a minimum fault current of 20% of rated current.

ii) Shall have residual compensation variable from 30-150%. iii) Adjustable Forward & Reverse Offset feature shall be provided in Zone-3 setting. iv) The measuring unit shall not become inoperative even under very severe close in system fault conditions where the potential may collapse to zero. Sound phase polarization and directional voltage memory should provide dynamically unlimited directional sensitivity. v)

The protective IEDs shall be suitable for use with electromagnetic Instrument Transformers.

Type-II i) Shall have phase segregated high impedance current differential protection suitable for EHV Overhead Transmission Lines and Cables in solidly or impedance grounded networks. ii) The protection shall be of unit type and shall cover 100% of the Line length. iii) A restrained dual biased operate characteristic shall be used and the highest phase current in any line shall be utilized as bias current. iv) Charging current compensation for increased sensitivity for long lines or cables shall be included. v) The IED shall be able to communicate with the remote end IED. vi) The communication channel shall be continuously monitored and an automatic switchover to a redundant channel shall be possible. vii) For line differential communication it shall be possible to select between a master-master system or a master-slave system depending on the functional or economic requirements. viii) An automatic switchover to master-slave communication shall take place if an interruption occurs in one communication channel in a master-master

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

16

communication system.

2

Zone Switching

3

Zone selection

4

Zone Timer

5

Offset Feature

6

Residual Compensation Memory Circuit

7

8

Power Swing Blocking

9

VT Fuse Fail

10 Auto Reclose

ix) Communication modules for dedicated communication for short and long distances (>60 km) shall be available. Zone switching to extend the reach of the measuring elements is not allowed. The reach of each zone shall be independently and individually adjustable and shall have setting in steps of 1% . Selection shall be so that the first zone of the IED can be set to about 80% - 90% of the protected line without any risk of nonselective tripping. Two independent continuously variable time setting range of 0 – 3 seconds for zone 2 and 0 – 5 seconds for zone 3. Shall have adjustment upto 20 % of Zone – 3 setting.

-

-

Shall have Residual compensation variable from 30 – 150%. Memory circuits with defined characteristics shall be provided in all three phases to ensure correct operation during close in 3 phase faults and other adverse conditions. Power Swing Blocking feature having suitable setting range to encircle the distance protection zones with an inbuilt timer having continuously adjustable time delay on pick up .The IED shall block tripping during power swing conditions. Shall have the provision to detect Single phase/Two Phase/Three Phase VT fuse failure. In case of VT fuse fail, the protection shall inhibit tripping by distance protection / Backup directional Protection. The IED shall be configured in such a For VT fuse fail of If a single set of VT either Main-I or fuse is used for Not applicable Main-II IEDs , supplying potential automatic switching to Main and Backup to Non-directional IEDs ,the protection Protection shall shall automatically inhibit. switched to Non directional protection for both the IEDs. Single and Three Pole High Speed Auto Reclosing feature selectable by external ARCO switch. Configuration : Configuration : Configuration : Three Pole High Single Pole High Three Pole High Speed Auto Speed Auto Speed Auto reclosing in the reclosing in the reclosing in the event of tripping by event of tripping by event of tripping by main Zone-1 distance Zone-1 distance protection. protection. protection.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

17

a) Configuration of the IED shall be such that, Autoreclose should not operate in case of tripping through – i) Zone-2 and Zone-3 Distance Protection (For Type-I and Type- II only) ii) Backup Directional Over Current and E/F Protection iii) Backup Non-Directional Over Current and E/F Protection iv) v) vi) b)

11 Switch on to Fault (SOTF)

12 Carrier Protection

Switch On to Fault Protection (SOTF) Local Breaker Backup Protection (LBB) Bus Differential Protection Variable Dead time range of 0.1- 60 seconds (minimum) with maximum step size of 0.01 sec. c) Variable Reclaim Time of 1-600 seconds (minimum) with maximum step size of 1.0 sec. d) In case of PLCC ‘Out of Service’, the IED shall be able for Auto Reclose. e) IED shall have multi shot auto reclose feature but shall be configured with single shot auto reclose. The IED shall comprise SOTF feature with an internal timer having variable time delay. For configuration of SOTF feature, contact of the TNC switch shall be used in such a fashion that at the time of closing the circuit breaker the feature shall initiate and remain active for the set time delay. Any further close pulse/holding the TNC switch in Close condition for more than the Set time of the feature, shall not affect the feature. In case of any fault irrespective of Zone during the set time of SOTF, the IED shall trip in Zone-1 time. Selection of the feature Not applicable shall be done by external CCO switch. The IED shall be configured in accordance with the principle of PUTT (Permissive Under reach Transfer Trip) Scheme. Configuration shall be such that in case of Zone-2 fault with receive of carrier signal from the remote end IED , the IED shall trip in Zone-1 time.Zone-1 shall be used as carrier starter. Zone-1 extension facility shall be available in case of PLCC is out of service. The IED shall be able to discriminate between Carrier Channel Fail and Carrier Out of Service.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

18

13 Local Breaker Back Up /Circuit Breaker Fail Protection

The protection shall deal with a situation where a circuit breaker fails to trip following receipt of trip command from associated tripping relays. All the protections that trip directly or indirectly the circuit breaker shall initiate the local breaker back up protection which after a suitable time delay shall initiate busbar clearance. The protection would trip all circuit breakers connected to the bus to which circuit with failed breaker is connected through the associated protection DC trip bus wires and the isolator auxiliary switches / switching relay contacts. Suitable arrangement shall be provided to short the bus bar protection check relay contact at negative side of the bus bar protection scheme. The protection shall not operate during the single-phase auto reclosing period. Separate alarm and indication from the local back up protection shall be provided for each circuit. The protective scheme shall include the necessary auxiliary relays etc. required for the above tripping functions. The LBB protection function for each circuit breaker shall be connected through the communication LAN and also with the bus bar protection at the bay level.

14 Parameter Group Selection

Shall have Four(4) parameter group having individual group setting of parameters for protection.

15 Check Synchronising / Dead Line Charging

Check-synchronising and Deadline Charging Feature shall be selectable by software. The check synchronising feature along with a timer having variable time range shall be inbuilt in the Main Distance IEDs.

16 Inbuilt Directional O/C and E/F Protection

Shall consist of back-up Directional O/C and E/F feature having IEC Definite Time, Normal Inverse, Very Inverse, Extremely Inverse Characteristics selectable by software. Provision of keeping the feature OFF shall also be present.

Not Applicable

17 Inbuilt Non Directional O/C and E/F Protection

Shall consist of back-up Non Directional O/C and E/F feature having IEC Definite Time, Normal Inverse, Very Inverse, Extremely Inverse Characteristics selectable by software. Provision of keeping the feature OFF shall also be present. The feature shall The feature shall be not be activated activated automatically in the automatically in the event of VT fuse event of VT fuse failure of only one failure of the Main Main protections. IED(Type-II) and Back Up IED (if one set of VT fuse is used for both the IEDs)

Not applicable

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

19

5.2.1.5-B

Backup Protection IEDs

All features detailed above for the Main IEDs except the features under section 5.2.1.5A(1)-(6),(15) shall be available in the Backup protection IEDs. Additional Guideline

The maximum fault current could be as high as 40 KA but the minimum fault current could be as low as 20% of rated current. The starting and measuring IEDs characteristics should be satisfactory under these extremely varying conditions. The protective IEDs shall be suitable electromagnetic Voltage Transformers.

for

use

with

Insulation barriers shall be provided to ensure that transient present in CT and VT connections due to extraneous sources do not cause damage to IED circuits. The circuits must comply with IEC recommendation for impulse withstand values. Adequate measures shall be taken to ensure that equipment is protected against voltage spikes occurring in Aux. DC supply. Disturbance Recorder, Fault Locator and Event Logger function may be an integral part of line protection IED, provided these meet specification requirements of the respective clauses of these equipments.

5.2.2

Auxiliary Relays and Tripping Relays (Applicable for all scheme)

5.2.2.1

Tripping Relay

Trip function shall be through a high speed tripping relay of the instantaneous type (operating time not to exceed 10 ms) and shall reset within 20 ms. It shall be D.C. operated and have adequate contacts to meet the requirement of scheme, other function like auto-reclose relay, LBB relay as well as cater to associated equipment like event logger, disturbance recorder, fault locater etc. It shall be provided with operation indications for each element coil.

5.2.2.2

Trip Circuit Supervision

The relay shall be capable of monitoring the healthiness of each ’phase’ trip-coils and associated circuit of circuit breaker during ’ON’ and ’OFF’ conditions. The relay shall have adequate contacts for providing connection to alarm and event logger. The relay shall have time delay on drop-off not less than 200 ms and be provided with operation indications for each phase.

5.2.2.3

DC Supply Supervision

The relay shall be capable of monitoring the failure of D.C. supply to which, it is connected. It shall have adequate potential free contacts to meet the scheme requirement. The relay shall have a ’time delay on drop-off’ of not less than 100 ms and be provided with operation indicator / flag.

5.2.2.4

Auxiliary relays

Auxiliary relays may be electro-mechanical or static as deemed appropriate. The auxiliary relays shall be designed for continuous operation at 220 VDC and shall withstand ±10% variation in rated voltage continuously. These shall generally be used for inter-locking and contact multiplication.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

20

5.2.2.5

Communication accessories

At least two numbers of compatible communication cables for communication of the respective IEDs with Laptop/Base Computer, all necessary software for communication, configuration, setting calculation(with setting calculation guide) of the IEDs shall be provided without any additional cost implication to the purchaser .

6

Additional Equipment

In addition to the requirements stated herein the following shall be an integral part of the protection system.

6.1

Time Synchronisation

One time synchronisation equipment shall be supplied which shall be located in the control room and shall receive Coordinated Universal Time (UTC) transmitted through GPS for time synchronisation of DRs, static energy meters, numerical protections and master clock. Shall be complete in all respects including antenna, all cables, processing equipment, etc. All auxiliary systems and special cables required for synchronisation of the various equipment shall work from the plant UPS system or from substation 220V DC supplies only and the bidder shall clarify if any built in battery backup is provided in which case same shall be of long life lithium batteries. It shall be compatible for synchronisation of Event Loggers, Disturbance recorders and SCADA at a substation. The synchronisation equipment shall have 2 micro-second accuracy. Equipment shall give real time corresponding to IST (taking into consideration all factors like voltage, temperature variations, propagation and processing delays etc). Shall be immune to hostile electrical environment. Suitable protections are to be provided against lightning surges and over voltages in power supply systems. The system shall be fully tested to the relevant international standards such as IEC:60255. One copy of all the test reports shall be enclosed with the bid. The synchronisation shall have one millisec accuracy. Shall give real time corresponding to IST (taking into consideration all factors like voltage, temperature variations, propagation and processing delays, etc.). The system should be able to track the satellites to ensure no interruptions of synchronisation signals. The output signal from each port shall be programmable at site for either hour, half hour, minute or second pulse as per requirements. The equipment offered shall have 6 output ports. Various combinations of output ports shall be from the following: • voltage signal: 3-5V continuously variable with 50ms minimum pulse duration. • potential free contact (minimum pulse duration of 50ms) and voltage rating of the contact shall be 250VDC/240VAC max. • IRIG-B • RS232C/RS485 These output ports shall be compatible with the requirement of the equipment to be synchronised i.e. numerical relays. The master clock in the control room shall also be

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

21

synchronised with the time synchronisation system. The equipment should have a periodic time correction facility of one second periodicity. The equipment shall also have real time display in hour, minute, second (24 hour mode) and have a separate time display unit to be mounted on top of control panel having display size of approx 100mm height.

7 Tests 7.1

Type Tests

Complete Type Test Reports from NABL accredited laboratory / Equivalent laboratory abroad in respect of the following aspects shall be submitted with the offer. The following type tests shall be conducted on the Protective relays. 1.

High Voltage Withstand – As per IEC-60255-5

i)

Dielectric Withstand

ii)

Impulse withstand

iii)

Insulation resistance

2.

Electrical environment -

i)

Auxiliary supply test,dc interruption- as per IEC 60255-11.The relay or its associated power supply is required to operate satisfactorily with a DC supply voltage range of 220V ± 20%. The performance shall not be affected due to - an interruption to the DC auxiliary supply of duration up to 10ms. - AC component (ripple) in the DC auxiliary supply up to 5% of rated value.,

ii)

High frequency disturbance – as per IEC 60255-22-1

iii)

Fast Transients – as per IEC 60255-22-4

iv)

Conducted electromagnetic field disturbance– as per IEC 60255-22-6

v)

Radiated electromagnetic field disturbance - as per IEC 60255-22-3

vi)

Radiated emission – as per IEC 60255-25

vii)

Conducted emission - as per IEC 60255-25

viii)

Electrostatic discharge – as per IEC 60255-22-2, (Class III and IV)

ix)

Surge immunity – as per relevant IEC

x)

Power frequency magnetic field – as per IEC 61000-4-8

3.

Atmospheric Environment-

i)

Temperature – as per IEC 60068-2-1-cold IEC 60068-2-2- dry heat

ii)

Humidity – as per IEC 60068-2-3,IEC 60068-2-30

iii)

Enclosure protection – as per IEC 60529

4.

Mechanical environment-

i)

Vibration – as per IEC 60255-21-1

ii)

Shock and bump- as per IEC 60255-21-2

iii)

Seismic – as per IEC 60255-21-3

5.

Relay characteristics, performance and accuracy test as per IEC 60255

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

22 • Steady state Characteristics and operating time. • Dynamic Characteristics and operating time for distance protection relays and current differential protection relays. 6.

Tests for rated burden as per IEC 60255-6

7.

Conformance Testing as per IEC 61850-10

7.2

Routine Tests

During fabrication, the panels shall be subject to inspection by the Purchaser to assess the progress of work as well as to ascertain that only quality raw material is used. Minimum three weeks notice shall be given to the Purchaser for witnessing the final testing of the complete equipment. The manufacturer shall furnish all necessary information concerning the supply to the inspectors. Routine test as per relevant BSS/ISS/IEC shall be carried out on each equipment, wiring in the presence of Purchaser’s representative if so desired by the Purchaser. All test reports shall be submitted for approval. Testing and commissioning of the panels at site shall be carried out by the manufacturer at no extra cost.

8

Co-ordination

The Bidder shall co-ordinate with the manufacturer/supplier of transformer, circuit breaker, disconnecting switches and PLCC equipment for co-coordinating the control, protection and inter-locking scheme of these equipments at no extra cost.

9

Documentation

The manufacturer shall develop the necessary general arrangement and schematic drawings adding necessary auxiliary devices, accessories, components etc which are required for safe, efficient and proper operation. The contract drawings shall cover but not be restricted to the following: 1. Dimensioned detail drawings of the panels showing front view, rear view and side view. 2. Template for foundation and details of cable trench and cable holes in the foundation platform. Elementary diagrams of all control, metering, protection, annunciation and other circuits. All devices shall be numbered according to ASA or international usage, which shall be separately coded. 3. Cabling and wiring diagram of the front and rear cubicles and interconnections between them, ferrule number, device numbers, grouping for cable take off etc. shall be distinctly shown. 4. Inter-connection diagram between switchboard and gear equipment, power transformers, instrument transformers etc. showing clearly the connection between the terminal blocks of the switchgear and control panel. 5. Dimensional outline, drilling diagram and special mounting arrangement, if any, of each type of various devices on the switchboard. 6. Internal wiring diagram of all devices and elementary wiring of relay where internal wiring is intricate. 7. Construction details of control switches, terminal block, test blocks etc.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

23 8. Dimensioned details of each unit cubicle complete assembly of panel. 9. Dimensioned front and rear view of the panels with instrument and device position marked. 10. List of all equipments and devices. 11. Pictorial views of control switches, indicating instruments, test blocks, terminal blocks and exploded views of draw out type instruments and fuse blocks. 12. Schematic and wiring diagram of the protection scheme, synchronising circuit, annunciator circuit. 13. All drawings shall also be submitted in reproducible format (preferably in AUTOCAD) without any additional cost implication to the purchaser. 14. Illustrative and descriptive literature, general technical data and specifications of each and every type of relays, meters, instruments and other devices offered. 15. Literature describing construction, operation adjustment and rating specifications of all the protection IEDs and auxiliary relays, recording instruments, metering instrument, control switches etc. 16. List of spare parts, identification number of renewable parts of relays, instruments and switches to enable the Purchaser to procure spare parts correctly at a later date.

10

Packing and Forwarding

The control panels shall be shipped to site packed in wooden crates. All equipment shall be divided, if required, into several sections for protection and ease of handling during transportation. They shall be wrapped with polythene sheets before being placed in the crates to prevent damage to finish. Crates shall have skid bottom for handling. Special notations giving details regarding the Purchase Order, weight and handling symbols shall be marked on the package. PTO for specific requirements.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

24

11

Sl.no.

Specific Requirements DUPLEX PANEL - FOR 220 KV LINES Instrument

CONTROL PART 1 Strip Mimic 2 36 way microprocessor based annunciator with repeat alarm contact and auxiliary relay 3 Semaphore indicators for earth switch 4 Control switch for circuit breaker 5 Control switches for isolators 6 Indicating lamps 7 Push buttons 8 Ammeter with transducer 9 Line voltmeter with transducer (from 1-ph CVT) 10 Wattmeter with transducer 11 Varmeter with transducer 12 Synchronising switch (lockable key type) 13 Synchronising socket 14 Protection transfer selector switch 15 Auto-reclose selector switch 16 Carrier selector switch RELAY PART 1 Main-I : Multifunction Distance Protection IED complete with test blocks, trip relays, auxiliary relays to complete the scheme 2 Main-II : Multifunction Distance Protection IED complete with test blocks, trip relays, auxiliary relays to complete the scheme 3 AC line under voltage relay for earth switch interlocking 4 DC supply supervision relay 5 Circuit Breaker Trip circuit supervision relay 6 Trip relay circuit supervision for above 7 High Speed Master Trip relay circuit for overall protection. 8 Set of test terminal blocks for protection CT

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

Quantity (For each Bay)

1 set 1 set 1 no. 1 no. as per scheme as per scheme as per scheme 3 nos. 1 no. 1 no. 1 no. 1 no. 1 no. as per scheme as per scheme 1 no. 1 set as per scheme 1 set as per scheme 1 no. 1 set 6 nos. 1 no. 1 no. 1 set

25

DUPLEX PANEL - FOR 220 KV LINES (PILOT DIFFERENTIAL REAYING) Sl.no. Instrument Quantity (For each Bay)

CONTROL PART 1 Strip Mimic 2 36 way microprocessor based annunciator with repeat alarm contact and auxiliary relay 3 Semaphore indicators for earth switch 4 Control switch for circuit breaker 5 Control switches for isolators 6 Indicating lamps 7 Push buttons 8 Ammeter with transducer 9 Line voltmeter with transducer (from 1-ph CVT) 10 Wattmeter with transducer 11 Varmeter with transducer 12 Synchronising switch (lockable key type) 13 Synchronising socket 14 Protection transfer selector switch 15 Auto-reclose selector switch RELAY PART 1 Pilot wire current Differential Protection IED complete with test blocks, trip relays, auxiliary relays to complete the scheme. 2 Numerical, fully discriminative, 3 phase directional over current and earth fault protection IED complete with test blocks, trip relays, auxiliary relays to complete the scheme. 3 4 5 6 7 8

AC line under voltage relay for earth switch interlocking DC supply supervision relay Circuit Breaker Trip circuit supervision relay High speed trip relay . Trip relay circuit supervision for above Set of test terminal blocks.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

1 set 1 set 1 no. 1 no. as per scheme as per scheme as per scheme 3 nos. 1 no. 1 no. 1 no. 1 no. 1 no. as per scheme as per scheme 1 set as per scheme 1 set as per scheme

1 no. 1 set 6 nos. 1 no. 1 no. 1 set

26

SPECIFICATION FOR METERING EQUIPMENT DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1

Scope

This specification covers (A) Design, manufacture, assembly, inspection and testing at original manufacturer’s works, supply on door delivery basis of Composite metering panels comprising : i) Microprocessor-based CT/PT operated,3-phase, 3-wire unbalanced load, 0.2S Class HT metering equipment for 220KV/132 KV Lines, HV/LV side of Power transformer. ii) Microprocessor-based CT operated, 3-phase, 4-wire unbalanced load,0.5S Class LT metering equipment for single-station auxiliary / grounding transformer feeder. iii) Test terminal blocks for in-situ testing of the meters. iv) All accessories including Networking and software as detailed in the subsequent paragraphs of this specifications. B) This specification also covers the followings: • Establishment of communication setup for Remote Meter Readings. • Setting up of Central Computer system with well proven software and protocol for data communication/processing. • Data collection from the energy meters and energy accounting and audit and MIS reports generation. • Training of DVC Engineers on the project and take over the meter reading activities and energy accounting and audit and MIS reports generation.

2

Standards

Equipment covered by this specification shall conform to latest issues the following Standards: 1. IS 14697 : AC static Transformer operated Watt-hour and VAR-hour meters, class 0.2S and 0.5S 2. IS 9000 : Basic environmental testing procedures for Electronic and Electrical Items. 3. IEC 62052-11 : Electricity Metering Equipments (a.c)-General requirements, tests and test condition. 4. IEC 62053-22 : Static meters for active energy (classes 0.2S and 0.5S) 5. CBIP Technical Report : 88 - Specification for AC static electrical Energy Meters. 6. CBIP Technical Report :111 - Specification for common meter reading Instrument.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

27 7. CBIP Technical Report: 93 - Study on tamper-proof methods for Energy meters. 8. CEA Regulation : 2006 - Installations and Operations of Energy meters. 9. IPC-A-610 : Acceptability of Electronic Assemblies Meters conforming to other international Standards which ensure better performance than the standards mentioned above shall also be considered. Salient points of difference between standards adopted and standards specified in this specification shall be clearly indicated in the relevant schedule and copy of such standards along with their English translation shall be furnished with the offer.

3 Function The metering equipment shall have at least the following functional features: 1. The energy accounting and audit meters shall also have the facility to measure, record and display with date and time at least the following parameters. All electrical parameters shall also be stored in a non volatile memory. (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m) (n) (o)

Serial Number of the Meter(Display only) CT ratio (Display only) PT ratio (For HT Meter only) Cummulative Active Energy Cummulative Reactive Energy Cummulative Apparent Energy Phase wise active power at peak KVA Phase wise reactive power at peak KVA Phase wise voltage at peak KVA Power down time Average power factor Line currents Phase voltages Date and time Tamper events

2. The energy accounting and audit meter shall have data storage capacity for at least 35 days in a non-volatile memory. 3. Energy accounting and audit meters shall have facility to allow download of parameters to Laptop/Desktop by suitable password protect software as well as transmission of data over communication network to a local and remote computer. 4. The meters shall be totally sealed and tamper-proof, with no possibility of any adjustment at site, except for a restricted clock correction.

4

Panel

Simplex Metering Panels shall be of size approximately 2200 mm (height),700 mm(depth),800 mm(width) fabricated from minimum 2(two) mm thick steel sheet(CRCA) totally enclosed , dust proof, weather proof and vermin proof, floor-mounted and self supported vertical front , indoor type cubicle provided with an access door in two halves at the back side with latch and locking arrangement . The bottom of the panel frame shall be about 100 mm high tie space all around, shall be erected by means of evenly spaced grout bolts projecting through base channel (MS) members of the frame, the panel shall be provided with suitable cable entry arrangement through bottom plates. Panel inside shall be painted with two coats of white enamel glossy paint and outside shall be painted with two coats of light grey shade-631 of IS: 5 or equivalent international standards. The degree of protection of panel shall be IP: 52. Panel wiring shall be standard switch board type, single core (stranded, minimum 7 conductor) annealed copper wires, PVC insulated suitable for tropical climate, FRLS type 1100 V grade.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

28 Wiring of PT circuit shall be with 1.5 sq. mm Cu and CT circuit with 2.5 sq. mm Cu respectively with standard ferrules and ring type Cu lugs. Panel shall be provided with common earthing rail that shall be connected with flexible GI strips with substation earthing. Ground bus of galvanized iron bar not less than 5 mm by 25 mm shall be provided along the back of panels, the ground buses shall be bolted to the frame of the panel in such a way as to make good electrical contact with the panel. Hinged doors and all equipment on the metering cubicle shall be connected to the frame with braided copper strip. Each metering panel shall contain the items and accessories listed at the end of this specification. Glass front panels with European standard swing frames and 19 inch rack mounting are also acceptable.

5 General Requirement Sl.

Requirement

HT Meter

1

Type

3 phase, 3 wire static energy meter with measurement (active, reactive, apparent energies), calculation, recording, printing, communication, tamper recorder modules in a single unit.

CT operated 3 phase, 4 wire static energy meter with measurement (active, reactive, apparent energies),calculation, recording, printing, communication, tamper recorder modules in a single unit.

2

Accuracy Class

0.2S The Meter shall start and continue to register the Energy flow at current value of 0.01 (1.0%) In and unity power factor. When the voltage is applied with no current flowing in the current circuit, the test output of the Meter shall not produce more than one pulse.

0.5S The Meter shall start and continue to register the Energy flow at current value of 0.01 (1.0%) In and unity power factor. When the voltage is applied with no current flowing in the current circuit, the test output of the Meter shall not produce more than one pulse.

3

Rated Current(In)

1 A and 5 A

5A

4

Rated Maximum Current

1.2 In

1.2 In

5

Reference Voltage(Vref)

110 V AC

Pressure Coil Voltage: 415V AC (4 wire directly fed) /240 V AC (Single phase directly fed)

6

Auxiliary Supply Dual supply. DC supply : 220 V ± 20% AC supply : 110 V AC For AC supply, auxiliary power shall be drawn from the three phases equally and the meter shall be able to remain powered up with availability of any two phases.

Sl.

Requirement

HT Meter

LT Meter

Dual supply. DC supply : 220 V ± 20% AC supply : From Pressure supply 415V / 240V. For AC supply, auxiliary power shall be drawn from the three phases equally and the meter shall be able to remain powered up with availability of any two phases. LT Meter

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

29

7

Power Consumption

As per indicated IEC

8

Internal Battery

9

Influence of supply voltage

As per indicated IEC

10

Voltage dips and short interruptions

As per indicated IEC

11

Influence of Short Time Over current

As per indicated IEC

12

Influence of self heating

As per indicated IEC

13

Influence of heating

As per indicated IEC

14

Immunity to Electromagnetic disturbance

As per indicated IEC

15

Radio Interference suppression

As per indicated IEC

16

Insulation

As per indicated IEC

17

Temperature range

As per indicated IEC

18

Clearance and creepage distances

As per indicated IEC

19

Starting and running with no load condition

As per indicated IEC

20

Accuracy Requirements

A

Limits of error due to variation of current

As per indicated IEC

B

Limits of error due to other influencing quantities

As per indicated IEC

C

Limits of error due to ambient temperature variation

As per indicated IEC

21

Data Storage

Shall be present for running internal calendar, clock and other important functions, whose life shall be at least 3 years. There shall be provision to indicate the health of the Battery.

Non volatile memory having a minimum retention time not less than 5 years.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

30

Sl.

Requirement

HT Meter

LT Meter

22

CT Ratio

User programmable.

User programmable.

(For calculation purpose, use of any multiplication factor is not permissible)

Minimum Available Range : Minimum Available Range : A) For 5 A Meter : 50/5, 100/5, 150/5, 200/5, 50/5, 100/5, 150/5, 200/5, 300/5, 400/5, 600/5, 300/5, 400/5, 600/5, 750/5,800/5, 1000/5, 750/5,800/5, 1000/5, 1500/5,1800/5 and 2000/5 1500/5,1800/5 and 2000/5 B) For 1 A Meter : 200/1,400/1,800/1,1500/1, 1600/1,1800/1and 2000/1

23

PT Ratio

User programmable.

(For calculation purpose, use of any multiplication factor is not permissible)

Available Range :

Not Applicable

33000/√3/110√3, 132000/√3/110√3 and 220000/√3/110√3

24

Communication port

a) Galvanic/ Optical Isolated Communication Port for connecting the Laptop/Desktop for data transfer. b) Pulse Output Front Port (for Active and Reactive) for calibration purpose c)

Remote communication port both programming and Data collection.

25

Method of calculation of Apparent Power/ Energy

TVM method

26

Integration period

15/30 minutes-user programmable.

27

Billing Period

The Billing Period shall be 24=00 hours of the last day of the month. However, this shall be user programmable for TOD Metering.

28

CT/PT error compensation Shall have the facility to compensate CT/PT Ratio and phase angle errors at different load points.

29

Display

for

Meter

Not Applicable

Shall have the facility to compensate CT Ratio and phase angle errors at different load points.

The Meter shall have at least 8 digit LED/LCD display. The different parameters shall be cycled by a Push Button. Push Button operation shall have the higher priority over the Auto Display. The display shall revert back to Auto Mode after a certain time after the last push button operation. The display shall contain at least the parameters as stated in Section(3) .The display shall have adequate resolution depending upon the load. For a lower value of CT ratio and/or low load, the unit of active reactive / apparent energy shall be selectable accordingly ,e.g for a low CT

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

31

Sl.

Requirement

HT Meter

LT Meter

ratio the measurement unit for active energy shall be in KWh and for a moderate to high CT ration the same shall be in MWh. 30

Billing report generation

Suitable software shall be Not Applicable provided for generation of billing report. If generation of billing report takes place as a result of resetting the Maximum demand , that shall take place automatically on the last day of the month at 24:00 hrs. For calibration and configuration purpose, provision of forced reset of maximum demand by password protected software and subsequent generation of part bill by billing software shall be present. Generation of billing report in other suitable way (except resetting the maximum demand) shall also acceptable. Collection of billing data and generation of billing report shall also be possible by the Central Computer through communication links.

31

Software and security of software

All software shall be compatible with latest version of Windows Operating System and shall be password protected. Provision for change of password by purchaser shall be available. The software shall be considered as integral part of the metering equipment. The software shall be considered as integral part of the metering equipment. Details of software packages to be supplied is detailed as follows : 1.Reading Software This Package shall consist of all necessary Software to perform the following functions: [A]

Collection of Billing Data(For HT Meter), Load Survey Data, information from the Meter after identifying the make of the Meter and Meter Sl. No. and store all the above data against each Meter Sl. No. and Make.

[B] Display any of the above data collected on its screen. Processing the above data for preparation of Bill(For

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

32

Sl.

Requirement

HT Meter

LT Meter

HT Meter), Load Survey Curve, Load Survey Chart (with Numerical Value), and Calculation of Average Power Factor etc. [C]

Printing of Bill and Billing Data(For HT Meter), Load Survey Curve, Load Survey Chart (with Numerical Values) etc. that has been processed in (C) above. This Package shall also consist of Operating System Software, Anti-Virus Software, Self-monitoring Software and driver Software necessary to install in the Base Computer/ Laptop. 2.Configuration Software This Package shall consist of all necessary software to configure the Meter to perform the following functions : [A] To programme the Meter Unit to act as Energy accounting and Audit meter as per CEA regulation: 2006. [B] To programme the Meter to operate as a TOD Meter or a non-TOD Meter(For HT Meter). [C] To Change number of TOD Time Zone and its timings (For HT Meter). [D] To change the Integration Period. [E] To change the CT ratio and PT ratio(For HT Meter). [F] To change the Billing Period(For HT Meter). [G] To incorporate any change of the Name of the consumer against Sl. No. of the Meter (if this facility is available). [H] To adjust the time of Internal Clock in case of drifting. [I] To perform any other special task, if any, available in the offered meter. 3.Remote Communication API (Application Programming Interface) to ensure that the meter data is compatible with the software for Energy accounting/Audit and MIS report generation installed at a remote server. Meter shall support IEC 62056-21/DLMS protocol. 32

Meter Sealing

Provision to seal the meter with all individual modules in their working position shall be available, so that it is not possible to draw out any of the modules without breaking the seal (s).

33

Front Cover

Preferably transparent with sealing facility. No internal part of the meter shall be accessible without breaking the seal.

34

Meter Case

Case of the meter shall be so constructed and arranged that any non-permanent deformation cannot prevent

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

33 satisfactory operation of the meter. The meter shall Sl.

Requirement

HT Meter LT Meter conform to the degree of protection IP 51.

35

Terminal Block

36

Clearance and Creepage Distances

As per indicated IEC

37

Connection Diagram

The connection diagram shall be marked on each Meter in an indelible and durable manner. The diagram shall indicate the marking of Meter Terminals as well as phase sequence for which the Meter is intended.

38

Nameplate

Following information shall be printed in an indelible and durable manner:

The Terminal Block of Meter shall be provided with a separate cover that can be sealed independently. This cover shall enclose the actual terminals, Conductor fixing Screws, a suitable length of the external conductors and their insulation and access to the terminals shall not be possible without breaking the seal(s) of Terminal Cover. The cover shall not, in any way, touch the Terminal fixing screws or bare portion of external conductors. Material of the terminal block shall comply IS:11731, Part-I.

1. Manufacturer’s Name and Type designation 2. Place and Year of manufacture. 3. Serial Number of Meter 4. Rated Voltage 5. Rated Current 6. Rated Frequency 7. Number of Phases and Number of Wires for which the Meter is designed. 8. Meter Constant and Transformation Ratios of CT, PT if included in Meter Constant. 9. Accuracy Class. 10. Auxiliary Supply Voltage 39

Time Synchronisation

Synchronisation of time shall be possible from an external source like GPS receiver/Central computer. The Internal Clock Shall feature 24 hours display with all consideration of a perpetual calendar.

40

Self Diagnostic feature

The meter shall be capable of performing complete selfdiagnostic check to monitor the circuits for any malfunctioning to ensures integrity of data memory location at all time. The meter shall have indication for unsatisfactory/nonsatisfactory/malfunctioning of the following: [A] Time and date on meter display. [B] All display segments on meter display

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

34

Sl.

Requirement

HT Meter

LT Meter

[C] Real time clock (RTC) status in meter reading prints out at the Central computer station in management information system. [D] Non volatile memory (NVM) status in meter reading prints out at the Central computer station in management information system. [E]

41

The meter shall have self diagnostic feature to indicate healthiness or any disorder of different modules. Configurable pulse outputs shall be provided for operation during any abnormal system condition or abnormal device condition causing ’alarm’. Such alarm events shall be indicated on front panel by LED’s and shall also be recorded and stored in non-volatile memory for retrieval through local or remote communication.

Tamper Recording Device Following Tamper Data shall be recorded by the Tamper Recording Unit to detect Tamper which can be down loaded to Base Computer/Laptop. 1. Current reversals and outages. 2. Unauthorised M.D. reset other than at the end of Billing Period (if MD reset feature is provided). 3. Removal of P.T. circuits in 1-Phase / 2-Phase / 3-Phase. 4. Removal of current in 1-Phase / 2Phase. 5. Unauthorised Programme Operation. 6. Individual Phase Power Losses in case of any Tamper. 7. Total Power Interruption. 8. Date and Time of last Tamper Reset and Total Number of Tampers. Snapshots of voltage, current, power factor and energy readings as well as date and time of logging of occurrence and restoration of all the above anomaly events shall be logged into meter memory which shall be available for retrieval through Base Computer/LAPTOP. This retrieval shall also be possible by the Central Computer through communication links. However, for total power interruption, the power ‘off’ and subsequent ‘on’ time should be logged with date and time. Maximum number of tampering events that can be stored in the meter shall be indicated.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

Not Applicable

35

6

Inspection & Testing

The equipment shall be tested at original manufacturer’s works in accordance with the relevant Indian, International standards in presence of Purchaser’s representative(s). The Supplier shall give Purchaser at least fifteen days’ notice of the equipment being ready at works for inspection. Routine test reports for all the equipment shall be submitted before inspection. Additional Tests which are felt necessary by the Purchaser’s representative(s) for checking of satisfactory operation/ functioning of the meter under different system/site conditions, but not included in the relevant standards may also be carried out during inspection. In case, inspection / test is carried out abroad at OEM works, then to and fro journey etc for at least two engineers shall be borne by the contractor.

7 7.1

Documentation Proof

The Bidder shall furnish proof of being the original manufacturer of the metering equipment.

7.2

Type Test Reports

Complete Type Test Reports from NABL accredited laboratory / Equivalent laboratory aboard in respect of the following aspects shall be submitted with the offer for the offered type of meter : a) Standard Electrical Values as per IEC 62052-11/ IS 14697 b) Accuracy requirements as per IEC 62053-22/ IS 14697 c) Electrical requirements as per IEC 62052-11/ IS 14697 d) Climatic Influences as per IS 14697. e) Mechanical requirement and tests including Vibration Test, as per IEC 62052-11/ IS 14697 f) Type test certificate of remote communication standards. The above type test reports shall be complete in nature including drawings and diagrams of the test meter.

7.3

Drawings, Literature

The manufacturer shall provide the following drawings and manuals along with their equipment. The number of copies required and mode of submission are covered in the SCC. All the routine and acceptance test reports shall be submitted to the appropriate authority for scrutiny and approval before issuance of dispatch clearance. Detailed dimensional drawings showing overall dimensions of each unit along with their mounting arrangement, layout and panel cut-out details. Schematic wiring diagrams showing in detail the connections to be made between different units. Instruction manuals of each of the equipment(s) and supplied software shall be provided by the bidder.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

36

8

Specific Requirements METERING EQUIPMENT PANEL

Sl.

Instrument

Quantity

TYPE - 1 01

Microprocessor based static CT/PT operated, 3 phase 3 wire unAs per quantities balanced loaded, HT Energy meters, class 0.2S with associated given in price test terminal blocks installed in the front side and mounting of the schedule meters and TTB shall be panel flush type.

02

Terminal Boards, CATD M4 (disconnecting type) or equivalent for CT/ PT circuit.

03

Terminal Boards stud type CATM6 or equivalent for other circuits As per requirement except CT/PT. plus 20% extra

04

Potential supply complete fuse assembly, (3 fuses + 1 link) HRC 2A 4 nos for each meter rating.

05

Complete fuse assembly :

i)

Panel LTAC incoming single phase 240 V, 50 HZ supply complete fuse assembly, 2 nos (1 fuses + 1 link). HRC 16A rating.

02 nos.

ii)

Panel Space Heater supply single phase 240 V, 50 HZ supply complete fuse assembly, 2 nos (1 fuses + 1 link). HRC 2A rating.

02 nos.

iii)

Panel illumination single phase 240 V, 50 HZ supply complete fuse assembly, 2 nos (1 fuses + 1 link). HRC 2A rating.

02 nos.

iv)

Panel socket single phase 240 V, 50 HZ supply complete fuse assembly, 2 nos (1 fuses + 1 link). HRC 6A rating.

02 nos.

06

Panel space Heater: 240V, 50 Hz, 100 W, of any reputed make.

01 no.

07

Thermostat (30 - 110 ºC), of any reputed make.

01 no.

08

Piano type switches , 240 V, 50 Hz , 6A

As per scheme

09

Power supply socket(3 pin type) , 240 V , 50 Hz, 6A

01 no.

10

Panel florescent type illumination fittings, 240 V, 50 Hz, 20 W.

01 set.

11

Door limit switch. 240 V, 50 Hz, of reputed make.

01 no.

12

FRLS, PVC insulated, annealed Cu flexible panel wires, minimum 1(one) lot 7 strands (2.5 sq.mm for CT and 1.5 sq.mm for PT circuit) as per requirement.

13

Lugs, nuts, bolts, washers, spring washers, channels, rails, and PVC type perforated Cable dressing enclosures etc as per requirement.

1(one) lot

14

Panel Earthing Rail and flexible GI strips for substation earthing connection.

1(one) set.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

As per requirement plus 20% extra

37

Sl.

Instrument

TYPE - 2 01 Microprocessor based Static CT operated, 3 phase 4 wire, Direct potential supply fed, LT Energy meters, class 0.5S with associated test terminal blocks installed in the front side and mounting of the meters and TTB shall be panel flush type. 02 03

Quantity

As per quantities given in price schedule

Data concentration unit, desktop/Laptop computer, power supply 1 set units and networking equipment if any Terminal Boards, CATD M4 (disconnecting type) or equivalent for As per requirement CT/PT circuit. plus 20% extra

04

Terminal Boards stud type CATM6 or equivalent for other circuits As per requirement except CT/PT. plus 20% extra

05

Potential supply complete fuse assembly, (3 fuses + 1 link) for each meter. HRC 2A rating. Complete fuse assembly : Panel LTAC incoming single phase 240 V, 50 HZ supply complete fuse assembly, (1 fuse + 1 link). HRC 16A rating.

4 nos for each meter

ii)

Panel Space Heater supply single phase 240 V, 50 HZ supply complete fuse assembly, (1 fuse + 1 link). HRC 2A rating.

02 nos.

iii)

Panel illumination single phase 240 V, 50 HZ supply complete fuse assembly, (1 fuse + 1 link). HRC 2A rating.

02 nos.

iv)

Panel socket single phase 240 V, 50 HZ supply complete fuse assembly, (1 fuse + 1 link), HRC 6A rating

02 nos

07 08 09 10 11 12 13

Panel space Heater: 240V, 50 Hz, 100 W, of any reputed make. Thermostat (30 - 110 0C), of any reputed make. Piano type switches , 240 V, 50 Hz , 6A Power supply socket(3 pin type) , 240 V , 50 Hz, 6A Panel florescent type illumination fittings, 240 V, 50 Hz, 20W Door limit switch. 240 V, 50 Hz, from Siemens or reputed make FRLS, PVC insulated, annealed Cu flexible panel wires, minimum 7 strands (2.5 sq.mm for CT and 1.5 sq.mm for pressure circuit) as per requirement. Lugs, nuts, bolts, washers, spring washers, channels, rails, and PVC type perforated Cable dressing enclosures etc as per requirement. Panel Earthing Rail and flexible GI strips for substation earthing connection.

01 no. 01 no. As per scheme 01 no. 01 set. 01 no. 1(one) lot

06 i)

14

15

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

02 nos.

1(one) lot

1(one) set.

38

SPECIFICATION FOR CIRCUIT BREAKERS DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1

Scope

This specification covers design, manufacture, assembly, testing at manufacturer’s works, supply and delivery of 245 KV, 145 KV SF6 and 36 KV SF6/Vacuum Circuit Breakers with all accessories, auxiliaries, terminal connectors, galvanised supporting structures and spares.

2 Standards The Circuit Breakers shall comply in all respect with the requirements of latest issue of following: 1. IEC 62271-100, High voltage alternating current circuit breakers. 2. IEC 62271-001, Common specifications. 3. IS 13118 Where the equipment offered conforms to any other standard, the salient points of difference between the standards adopted and IEC recommendation shall be clearly indicated and the English version of the proposed standard shall be furnished.

3

Function

Circuit breaker shall be totally restrike free under all duty conditions and shall be capable of performing these duties without the use of a opening resistance. The breaker shall withstand high stresses during fault clearing, load rejection and reenergisation of lines with trapped charges. The circuit breaker shall be capable of auto-reclose operations. The breaker shall be capable of interrupting rated power with recovery voltage equal to the rated maximum line to line service voltage at rated frequency and at a power factor not exceeding 0.15. The breaker shall be capable of satisfactory operation ever under condition of phase opposition that may arise due to faulty synchronizing. The maximum power, which the Breakers can satisfactorily interrupt under phase opposition, shall be stated in the tender. The circuit breaker shall be capable of interrupting line charging currents without undue rise in the voltage on supply side and without any re-strike and without showing signs of undue strains. Rated line charging breaking current shall not be less than 50 Amps. The guaranteed over voltage caused while interrupting the above charging current shall be as per the relevant IEC Standards.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

39 The breaker shall be capable of interrupting small inductive current also such as those occurring while switching off unloaded transformer without restrikes as indicated in the relevant IEC Standards. The breaker shall be capable of interrupting – (a) the rated power with restriking voltage having a frequency of not less than 400 c/s and (b) 50% of nominal breaking capacity with restriking voltage at freq. of 2000 c/s. Complete data for the frequency amplitude factor etc. for the rate of rise of restriking voltage shall be furnished. The maximum rating of single bank of shunt capacitors which can be switched by the Circuit breakers without re-strikes shall be as per IEC Standards. The interrupting capacity of the breakers for kilometric faults (short line faults) shall be equal to its interrupting capacity as earlier specified.

4

Operating Mechanism

Closing circuits - shall operate correctly at all values of supply voltage between 85% and 110% of the rated voltage. Trip circuits - two independent tripping circuits, valves, pressure switches and coils per pole to be provided for connection to different protection systems in the case of 245 KV breakers. 145 KV and 36 KV breakers will be provided with two independent tripping circuits, valves, pressure switches and coils per operating mechanism. The circuits shall operate correctly under all operating conditions and at all values of supply voltage between 70% and 110% of rated value. There shall be provision for trip circuit supervision for both pre and post close positions. Operation - shall have both remote and local operation provision with each mode selectable with a remote/local selector switch. Pressure switch and Densimeter - contacts suitable for direct use as permissive in closing and tripping circuits to be provided. DC supply monitoring - to be provided for all auxiliary circuits. Provision for remote annunciation and back-up capacitor trip shall be provided. Operating mechanism - shall be pneumatic, electro-hydraulic or spring charged type or any combination of these.

4.1

Pneumatic

1. Shall operate at air pressure limits of 85% to 110% of rated pressure. At these limits the specified make/break times shall be met. 2. The compressor shall be automatic start-stop type. Manual control shall also be provided. Pressure lockout device to be provided with remote alarm indication for trip lockout for both coils, close lockout and auto reclose lockout. 3. On failure of power supply, at least 2 CO operations should be possible at the lowest for auto reclose duty without refilling.

4.2

Hydraulic

1. On failure of power supply and pressure equal to the lowest pressure of auto reclose duty, at least two CO operations should be possible. Also complete duty cycle of breaker to be possible when oil is at its lowest permissible pressure before make up. 2. Provision for monitoring pressures of oil, nitrogen, reservoir to be kept both at local

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

40

and remote ends.

4.3

Spring charging

1. Motor shall be rated to fully charge the closing springs in less than 30 seconds and shall have adequate thermal rating for repeated sequence of closing and opening operations of breaker. 2. In the event of failure of power supply, at least one CO operation should be possible. Breaker operation should not be possible when spring is in partially charged condition.

3.

5

Construction

Outdoor type - The circuit breakers shall be of outdoor SF6 gas single pressure type for 245 KV,145 KV and SF6 / VCB for 36 KV mounted on steel structures. Operating mechanism for 245 KV Circuit Breaker - The 245 KV circuit breakers shall have individual discrete single pole units for each of the 3 phases along with separate motor operating mechanism/ unit compressor pneumatic mechanism/ Electro hydraulic mechanism for each pole, suitable for single/ three phase rapid auto-reclose operation in the rated operating duty cycles as specified in respective clause where applicable. Operating mechanism for 145 KV & 36 KV Circuit Breaker - The 145 KV and 36 KV circuit breakers shall have three separate but identical single pole units operated through a common shaft (gang operated) with single motor operating mechanism / unit compressor pneumatic mechanism/ Electro hydraulic mechanism. The 145 KV CB shall also be suitable for three phase rapid auto-reclose operation in the rated operating duty cycles as specified in respective clause where applicable. Gas leakage – The design and construction of the Circuit Breaker shall be such that the gas leakage will be limited to 1% per year. No condensation of SF6 gas shall take place on internal insulating surface. Interrupting chambers - Inside the interrupting chambers, there shall be an absorbent to eliminate SF6 gas decomposition products and moisture. The Breaker poles should be so arranged that individual breaker poles can be removed without leakage of SF6 gas. Gas density monitor - A suitable gas density-monitoring unit (temperature compensated) shall be provided to automatically block the operation of the circuit breaker on the loss of gas pressure. Upon loss of pressure the gas between open contacts shall be suitable to withstand at least the rated voltage at zero gauge pressure of gas. Special seal - Special seal shall be provided to restrict the SF6 gas inside the insulator column. The position of vents, diaphragms and pressure relief devices, if required, shall be so arranged as to minimize danger to the operator in the event of gas or vapor escaping under pressure. Main contacts - The main contacts shall have ample area and contact surface for carrying the rated current and the short time rated current of the circuit breakers without any excessive temperature rise. The main and arcing contacts shall be adjustable to allow for wear and shall be easily replaceable. Arc-quenching The arc-quenching device shall be of robust construction and shall not require any critical adjustment. The device shall be easily removable for access to the Breaker contacts. It shall be so designed as to satisfactorily interrupt low value low power factor inductive and capacitive currents at the rated voltage plus ten percent. If multibreak interrupter are used they shall be so designed and augmented as to ensure a fairly uniform voltage distribution across them. Sealed units - For sealed units of 36 KV VCB, contact erosion indicator shall be provided.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

41

Mechanism housing - The operating mechanism and all accessories shall be enclosed in a weather proof sheet steel mechanism cabinet. Hinged door shall provide access at least from the front. The mechanism housing shall be padlocked and lock with duplicate keys has to be furnished. Suitable space heaters with automatic thermostatic control shall be mounted in the housing to prevent condensation. Terminal blocks - Terminal blocks shall be furnished inside the mechanism housing or in a separate enclosure. A minimum of ten spare terminals for control wiring shall by provided. All wiring in the housing shall be flame proof and vermin proof. All terminals and end connectors shall tinned. Suitably rated switch shall be provided to enable the control supply of the Breaker to be cut off from the mechanism housing. Local and remote operation - There shall be provision for both local and remote electrical operation. Safety precaution - There shall be suitable protection to prevent breaker operation under low gas pressure. Cable glands - Requisite number of cable glands shall be provided at the bottom of the operating cabinet to receive the Purchaser’s control cables. The number and sizes of the cable glands will be intimated to the successful Bidder. Illumination - A suitable lighting point with its associated control switches and socket pin plug outlet shall be provided inside the mechanism housing or enclosure for use in emergency. Auxiliary contacts - An adequate number of breaker auxiliary contacts shall be provided to suit control, interlock and auto-reclose schemes. There shall be at least 12 nos. of auxiliary contacts of each type (NO and NC) for 245 KV breaker and 8 nos. of spare auxiliary contacts of each type (NO and NC) for 145 KV and 36 KV breakers to incorporate, if so required, additional features in the control schemes. The contacts may be called upon to break the opening and closing inductive coil current rated 2 Amp at 250/220 VDC. At least two limit switches for each spring charging mechanism shall be provided. All Breaker auxiliary contacts and limit switch contacts should be terminated in terminal blocks. At least ten spare terminals should be provided per pole. Meters and guages - The operating mechanism box shall be provided with adequate number of gauges and meters for monitoring the pressure density of SF6 gas. Interlock - Electrical and mechanical interlock shall be provided. The circuit breakers shall be suitable for interlocking with their associated isolators. Low gas pressure alarm and indication shall be provided. Very low gas pressure lockout with alarm and indication shall also be provided. Electrical clearance - The clearance between the live parts and grounded structure shall not be less than those specified in the relevant International or Indian Standards. Quality and Storage of gas - The SF6 gas used shall conform to IEC 60376, ed-2. Bidder should indicate the method of storing of the CB and SF6 in stores till erected and commissioned. Support structure - The circuit breakers shall be supplied with steel supporting structures. These shall be galvanised and shall be designed to allow a minimum factor of safety of 2.5 with respect to the yield point under conditions for maximum loading, allowing for wind pressure of 200kg/sq.cm on 1.25 times the projected area of such member of one face and taking into account the dead and the stock loads of the circuit breaker. Terminal connectors - Each circuit breaker shall have expansion type terminal connectors both for incoming and outgoing terminals suitable for 3/2.5/ 1.5 inches IPS Aluminium tube as indicated in the schedule of rates. Each terminal connector should be suitable for both vertical and horizontal connection. Marshalling Kiosk – Shall be made of at least 2 mm thick sheet steel and properly illuminated.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

42

Earthing - Each Circuit Breaker pole and Control Cabinet shall be provided with a minimum of two grounding pads/ terminals and clamps for grounding connections. Paint - All interiors and exteriors of mechanism housing and enclosure cabinet/marshalling kiosk and other metal parts shall be thoroughly cleaned to remove all rusts, scales, corrosion, grease or other adhering foreign material. All steel surfaces in contact with insulating oil as far as accessible shall be painted with not less than two coats of heat resistant, oils insoluble insulating varnish. Steel surfaces exposed to the weather shall be given a primer coat of zinc chromate and two coasts of weather resistant paint. All metal parts not accessible for painting shall be made of a corrosion resistant material. All machines finished or bright surface shall be coated with suitable preventive compound and suitably wrapped or otherwise protected. All paints shall be carefully selected to withstand tropical heat and extremes of weather. The paint shall not scale off or crinkle or be removed by abrasion due to normal handling. Adequate quantity of spare paint for retouching at site shall be furnished. Erection & Maintenance Tools - Any special tools required for SF6 Circuit Breakers for initial erection and subsequent maintenance of the Circuit Breakers shall be indicated.

6

Fittings and Accessories

The following fittings and accessories shall form a part of each circuit breaker: 1. SF6 gas pressure gauge and gas density temperature compensated pressure switch. 2. Provision for replenishing SF6 gas 3. Lockout Device. 4. Mechanically operated tripping and closing Device. 5. Local/ remote/ off Changeover Switch. 6. Local electrical closing and tripping push buttons/knobs. 7. Operation counter. 8. Interlocking device. 9. Terminal Connectors. 10. Supporting frame. 11. Earthing terminals. 12. Name Plate. 13. Foundation bolts. 14. Mechanical ON and OFF position indicator. 15. Capacitor tripping device along with a circuitry for testing its health. 16. Anti-pumping device. 17. Pole discrepancy unit (for 245 KV breakers). 18. Handle for manual charging of Closing Springs. 19. Isolating Switches/MCB to cut-off control power supply (220 ±20% DC) 20. Fuses. 21. Space heater 22. Operating mechanism either pneumatic or hydraulic or motor operated spring. 23. Arc quenching devices and contacts,completely sealed into the insulated interrupting chamber. 24. Contact erosion indicator (for VCB). 25. All erection and maintenance tools for breakers and also for compressor of pneumatically operated breaker.

7

Design Rating

The rating of the Circuit Breakers covered by this specification are detailed in the section - Tender Specific Requirements.

8

Insulation

The insulation to ground, insulation between open contacts and the insulation between

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

43

phase of the completely assembled Circuit Breaker shall be capable of withstanding satisfactorily dielectric test voltages corresponding to BIL specified herein. The level of insulation shall be as follows: 1. One minute power frequency withstand voltage - 460KV/ 275KV/ 70KV for 245 KV/ 145 KV/ 36 KV breakers respectively. 2. Impulse withstand voltage of positive and negative polarity - 1050KV/ 650KV/ 170KV for 245 KV/ 145 KV/ 36 KV breakers respectively. The clearances in air viz. minimum clearance between phases and that between live parts and grounded objects on the basis of the BIL specified shall be specifically mentioned in the tender in case the apparatus is not impulse tested after complete assembly. The clearances shall be in line with the indicated standard. The external insulator supports shall be designed for BIL as indicated above and shall be suitable for installation in contaminated atmosphere. Bushing shall conform to latest issue of BS 3297 or IS 2099 or equivalent. The porcelain used shall be homogeneous and free from cavities and other flaws. They shall be designed to have ample insulation, mechanical strength and rigidity for satisfactory operation. All bushing of identical ratings shall be interchangeable. The insulation of the bushings shall be coordinated with that of the Circuit Breakers. The puncture strength of the bushing shall be greater than the dry flash over value. When operating at normal rated voltage there shall be no electric discharge between the conductors and bushings, which would cause corrosion or injury to conductors, insulators, or supports. The bushings shall be free from radio disturbance when operating at a voltage upto 10% above rafted voltage and shall also be free from external and internal corona. All iron live parts shall be hot dip galvanised. All joints shall be the SF6 gas/ air/ oil tight. The surface of the joints shall be rued up. The design of the bushing shall be such as to ensure a uniform compressive pressure on the joints. Table: Insulation Level for Bushings (Withstand Values). 1. Voltage level - 245 KV Insulation classification Low frequency withstand voltage, 1 min. dry (KV RMS) Low frequency withstand voltage, 1 min. wet (KV RMS) Impulse voltage (1.2x50 microsec impulse) Creepage distance minimum (cm/KV)

: : : : :

245 KV 460 KV 460 KV 1050 KVp 2.5

2. Voltage level – 145 KV Insulation classification Low frequency withstand voltage, 1 min. dry (KV RMS) Low frequency withstand voltage, 1 min. wet (KV RMS) Impulse voltage (1.2x50 microsec impulse) Creepage distance minimum (cm/KV)

: : : : :

145KV 275 KV 275 KV 650 KVp 2.5

3. Voltage level – 36 KV Insulation classification Low frequency withstand voltage, 1 min. dry (KV RMS) Low frequency withstand voltage, 1 min. wet (KV RMS) Impulse voltage (1.2x50 microsec impulse) Creepage distance minimum (cm/KV)

: : : : :

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

36 KV 70 KV 70 KV 170 KVp 2.5

44

9

Temperature Rise

The temperature rise and the maximum temperature attained by any part of the equipment other than coils but inclusive of contacts when in service at site under continuous full load conditions and exposed continuously to the direct rays of the sun shall not exceed the permissible limits fixed by approved standards. When the standards specify the limits of temperature rise, these shall not exceed when corrected for the difference between ambient temperature at site and the ambient temperature specified in the approved standards.

10

Tests

Each Circuit breaker shall comply with type test carried out at NABL accredited laboratory / Equivalent laboratory aboard and shall individually be subjected to routine tests prescribed in indicated standard. Reports of all type tests as stipulated in indicated standard and the line charging current and transformer charging current interrupting tests shall be furnished along with the tender. Routine tests and acceptance tests as per the referred standard including speed tests shall be carried out on each type of Breaker in presence of the Purchaser’s representative if so desired by the Purchaser. A millivolt drop test shall be made across the Circuit Breaker contacts and between terminals for comparison with the type test for temperature rise at rated normal current. A dielectric power factor test shall be carried out on the bushing and detailed test result shall be furnished. The operating motors shall be tested in accordance with the relevant BS or equivalent. The Contractor shall give Purchaser at least three weeks notice of any equipment being ready for testing. After the inspection and testing the Contractor shall forward to the Purchaser six certified copies of the test results and certificate for approval of the Purchaser. The equipment shall be despatched only after the test certificates have been approved by the Purchaser in writing and despatch clearance is issued.

11

Spares

Manufacturer shall guarantee that he will supply spare parts if and when required on agreed basis for the life of the supplied items. The agreed basis shall be the published catalogue prices at the time of supply of the Spare Parts. The manufacturer shall provide adequate advance notice before phasing out any spare part from their product line. The following shall constitute the set of mandatory spares: 1. Complete set of SF6 gas filling unit for SF6 Circuit Breaker including its suitable carriage. 2. Complete set of SF6 gas evacuating Unit. 3. SF6 gas leak detector Unit. The Bidder shall guarantee that before going out of production of the spare parts , he will give prints,drawings of spare parts and specification of materials at no cost to the purchaser,if and when required to enable the purchaser to fabricate or procure spare parts from other source.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

45

12 Drawings & Documentation The manufacturer shall provide the following drawings and manuals along with the circuit breakers. The number of copies required and mode of submission is covered on the SCC. 1. General outline drawings showing dimensions, clearance and other details, net weight and shipping/ transportation weight etc. Sectional views showing general constructional features of the Breaker and operating mechanism. 2.

Foundation drawings of all component parts of the equipment including structure mounting and structural drawing clearly showing details of the foundation required for these parts foundation loads and details of all ducts, trenches etc. required for pipes cables and other accessories.

3.

Type test reports of similar rated Circuit Breaker conforming to the indicated standard to be submitted along with the offer.

4.

Any other relevant drawings and/or literature which the Bidder might decide to be necessary for explaining the constructional and operational features of the Circuit Breakers.

5.

General outline drawing.

6.

Assembly and sub-assembly drawings of the Breaker. All parts shall be labeled and numbered to enable the Purchaser to order for spare parts if necessary.

7.

Detailed dimensions and assembly of Bushings.

8.

Detailed dimension and assembly of important auxiliaries.

9.

Wiring and control schematics diagram with ferrule numbers, kiosk terminal numbers and interlock system.

10. Interlock system. 11. General outline drawing of piping. 12. Bill of Materials with make,rating and quantity of each component. 13. Details of Terminal Pad. 14. Nameplate 15. Sectional Views showing general constructional features of the breaker and operating mechanism. 16. Interrupter assembly drawing. 17. Details of spare contacts of different relays/contactors/sensors with Circuit Breaker kiosk terminal numbers. 18. Wiring/interconnection diagram for each equipment and terminal block. 19. Test report of terminal connectors with detailed drawings is to be submitted by the successful Bidder for technical approval. 20. Erection, operation and maintenance manual of the equipment before effecting delivery of the Breakers. The instruction Manual shall include a list of spare parts.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

46

13

Specific Requirements CIRCUIT BREAKERS

Sl.

Description

Parameter

1

2

3

245KV CIRCUIT BREAKER 1 Rated voltage 2 Interrupting medium 3 Type 4 5 6 7 8

245KV SF6 Restrike free, without PIR 3 2000 50 17000 17000

9 10

No. of Poles Rated normal current in Amps Frequency (cycles per sec) Symmetrical Breaking Capacity in MVA - 1st Break Symmetrical Breaking Capacity in MVA - 2nd Break after auto reclose Symmetrical Breaking current at rated voltage (kA) Max. Capacity peak current during first half cycle (kA)

11

Short time current (3 sec)

12

Operating duty

13

19 20 21

Auto-reclose time (cycle from instant of trip coil energizing to the instant of contact fully closed) Latching requirement Interrupting time (cycles) Ambient Temperature Temperature rise above ambient under continuous full load operation - For current carrying parts in SF6 including contacts (in o C) Temperature rise above ambient under continuous full load operation - For all other parts in direct contact with insulation other than SF6 gas (in oC) Over voltage factor consequent to low inductive current switching Basic Insulation level (KVp) Insulation level - 1 min power freq withstand voltage (KVrms)

22

Insulation level - 1.2 / 50 micro-sec Impulse withstand (KVp)

1050

23

Operating Mechanism

24 25

Restriking Voltage Rate of rise of restriking voltage

Motor operated Spring or pneumatic or hydraulic with anti-pumping and trip free features As per IEC As per IEC

14 15 16 17

18

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

40 100 Not less than rated symmetrical breaking current. (O - 0.3sec - CO 3min - CO) 12 - 20 cycles adjustable Trip free operation Less than 4 cycles 50°C As per IEC:62271-100

As per IEC:62271-100

Not less than 2 1050 460

47

Sl.

Description

Parameter

1

2

3

26

Power supply for operating mechanism

11

Short time current (3 sec)

12

Operating duty

13

19 20 21 22 Sl.

Auto-reclose time (cycle from instant of trip coil energisation to the instant of contact fully closed) Latching requirement Interrupting time (cycles) Ambient Temperature Temperature rise above ambient under continuous full load operation - For current carrying parts in SF6 including contacts (in oC) Temperature rise above ambient under continuous full load operation - For all other parts in direct contact with insulation other than SF6 gas (in oC) Over voltage factor consequent to low inductive current switching Basic Insulation level (KVp) Insulation level - 1 min power freq withstand voltage (KVrms) Insulation level - 1.2 / 50 micro-sec Impulse withstand (KVp) Description

1

2

Single phase AC 240V 50Hz / 3-phase AC 415V 50Hz 27 Radio interference voltage at 156 KVrms in microV < 1000 28 Minimum creepage distance in mm 6125 29 Closing and trip coil voltage 220V DC 30 Number of trip coils Two per pole 31 Number of closing coils per pole One 32 First pole to clear factor 1.3 33 Clearances As per indicated Std. 34 Noise level at base and upto 50 meters distance from the base of 140 dB 35 Rating of auxiliary contact 10A,220V DC 36 Breaking capacity of auxiliary contact 2A DC with time constant not less than 20ms 145KV CIRCUIT BREAKER 1 Rated voltage 145KV 2 Interrupting medium SF6 3 Type Restrike free, without PIR 4 No. Of Poles 3 5 Rated normal current in Amps 2000 6 Frequency (cycles per sec) 50 7 Symmetrical Breaking Capacity in MVA - 1st Break 10000 8 10000 Symmetrical Breaking Capacity in MVA - 2nd Break after auto reclose 9 Symmetrical Breaking current at rated voltage (kA) 40 10 100 Max. Capacity peak current during first half cycle (kA)

14 15 16 17

18

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

Not less than rated symmetrical breaking current. (O - 0.3sec - CO 3min - CO) 12 - 20 cycles adjustable Trip free operation Less than 4 cycles 50°C As per IEC:62271-100

As per IEC:62271-100

Not less than 2 650 275 650 Parameter 3

48

23

Operating Mechanism

1

Rated voltage

36KV

2

Interrupting medium

SF6/ Vacuum

3

Type

4

No. Of Poles

Restrike free, without PIR 3

5

Rated normal current in Amps

2000

6

Frequency (cycles per sec)

50

7

Symmetrical Breaking Capacity in MVA - 1st Break

1500

8

1500

9

Symmetrical Breaking Capacity in MVA - 2nd Break after auto recluse Symmetrical Breaking current at rated voltage (kA)

25

10

Max. Capacity peak current during first half cycle (kAp)

62.5

11

Short time current (3 sec)

12

Operating duty

13 14

Auto-reclose time (cycle from instant of trip coil energisation to the instant of contact fully closed) Latching requirement

Not less than rated symmetrical breaking current. (O - 0.3sec - CO 3min - CO) NA

15

Interrupting time (cycles)

Less than 4 cycles

16

Ambient Temperature

50°C

Sl.

Description

Parameter

1

2

3

Motor operated Spring or pneumatic or hydraulic with anti-pumping and trip free features 24 Power supply for operating mechanism Single phase AC, 240V 50Hz / 3-phase AC, 415V 50Hz 25 Radio interference voltage at 156 KVrms in microV < 1000 26 Restriking Voltage As per IEC 27 Rate of rise of restriking voltage As per IEC 28 Minimum creepage distance in mm 3625 29 Closing and trip coil voltage 220V DC 30 Number of trip coils Two 31 Number of closing coils One 32 First pole to clear factor 1.3 33 Clearances As per indicated Std. 34 Noise level at base and upto 50 meters distance from the base of 140 dB 35 Rating of auxiliary contact 10A,220V DC 36 Breaking capacity of auxiliary contact 2A DC with time constant not less than 20ms 36KV CIRCUIT BREAKER

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

Trip free operation

49

17

Temperature rise above ambient under continuous full load operation - For current carrying parts including contacts (in oC)

As per IEC:62271-100

18

As per IEC:62271-100

19 20 21 22

Temperature rise above ambient under continuous full load operation - For all other parts in direct contact with insulation other than SF6 gas (in oC) Over voltage factor consequent to low inductive current switching Basic Insulation level (KVp) Insulation level - 1 min power freq withstand voltage (KVrms) Insulation level - 1.2/ 50 micro-sec Impulse withstand (KVp)

23

Operating Mechanism

24

Power supply for operating mechanism

Motor operated Spring anti-pumping and trip free features Single phase AC 240V 50Hz / 3-phase AC 415V

25

Restriking Voltage

As per IEC

26 27 28 29 30 31 32

Rate of rise of restriking voltage Minimum creepage distance in mm Closing and trip coil voltage Number of trip coils Number of closing coils First pole to clear factor Clearances

As per IEC 900 220V DC Two One 1.5 As per indicated Std.

33 34 35

Noise level at base and upto 50 meters distance from the base of 140 dB Rating of auxiliary contact 10A,220V DC Breaking capacity of auxiliary contact 2A DC with time constant not less than 20ms

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

Not less than 2 170 70 170

50

SPECIFICATION FOR ISOLATORS DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA – 700054

1

Scope

This specification covers the design, manufacture, testing at manufacture’s works, packing and delivery of motor/ manually operated isolators of the following types: 1. Single pole, outdoor, central post rotating, double break, 245 KV, 1050 KVp BIL, motor operated isolator (normal/ tandem type), 3 single pole units to be operated as complete set/ unit for 3-phase operation suitable for horizontal upright mounting with all accessories, motor driven mechanism, electrical and mechanical interlocks, 2 unit solid core post insulator stack with and without earth switches. 2. Single pole, outdoor, central post rotating, double break, 145 KV, 650 KVp BIL, motor operated isolator (tandem type), 3 single pole units to be operated as complete set/ unit for 3-phase operation suitable for horizontal upright mounting with all accessories, motor driven mechanism, electrical and mechanical interlocks, 2 unit solid core post insulator stack with and without earth switches. 3. Triple pole central post rotating, double break, low level, normal, outdoor type, 145 KV, 650 KVp BIL, motor operated isolator suitable for horizontal upright mounting with all accessories, motor driven mechanism, electrical and mechanical interlocks, 2 unit solid core post insulator stack with and without earth switches. 4. Triple pole central post rotating, double break, outdoor type, 36 KV, 170 KVp BIL, manually gang operated, low level, isolators suitable for horizontal upright mounting with all accessories, manual operating mechanism, electrical and mechanical interlocks, 2 unit post type stack insulators with and without earth switch.

2

Standards

The equipment shall conform to the latest edition of the following standards: 1. IS: 9921(Part-I to Part-V)- Specification for Alternating Current disconnectors (Isolators) and Earthing Switches for voltages above 1100V. 2. IS: 2544, Porcelain post insulators for systems with nominal voltage greater than 1000 Volts. If standards other than those specified above are adopted than the same shall be stated. The performance and operation of the equipment in such case shall be equal to or better than the specified standards.

3 3.1

Construction General

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

51 All 245 KV and 145 KV tandem isolators shall comprise of three, single pole units, each with its own operating mechanism box complete with motor and control circuits. These single pole units (for R, Y, B) shall be electrically ganged to perform the three phase service requirements stated herein. There shall be no sharp corners or points on the live parts. Shields shall be furnished wherever necessary. The fixed and moving contacts shall be made of hard drawn electrolytic copper. The terminal pads shall be made of copper with tin plating. All ferrous parts shall be corrosion protected by hot dip galvanizing to conform to IS : 2633. All fasteners shall be locked in position. The design of mechanism shall be such as to prevent over travel of contacts when operated manually or electrically. The operating rods or pipes shall preferably be provided with universal coupling to account for angular misalignment. No moving parts shall require lubrication at intervals of less than one year. The equipment shall be designed to withstand the electrical and mechanical stresses imposed by system fault conditions. There shall be no harmful rise in temperature due to flow of short circuit current for time period indicated in the rating requirements.

3.2

Support structure

The isolators shall be mounted on a supporting structure. The details of the supporting structure shall be obtained from the Purchaser. All design data including base channel’s mounting holes are to be matched with the above structure.

3.3

Operating mechanism

3.3.1 245 KV & 145 KV Isolator Each pole of a 245 KV isolator / 145 KV tandem isolator shall have its own mechanism box motor drive unit. The individual mechanism boxes shall be connected to a master kiosk. The master kiosk shall incorporate pole discrepancy units besides other functions. All local/remote electrical operations shall be performed via the common kiosk. There shall be provision for local manual operation also. The torque required for local manual operation shall not be more than 30 Kg. Meter. 145 KV normal isolator shall be 3 pole mechanically ganged with motor operating mechanism. All bearings shall be heavy duty, lubricated for high life and sealed against dust and moisture. Suitable guides shall be provided for operating drive of earthing switch. The mechanism shall ensure simultaneous and identical operation of the speed of the blade during make and break will be such that there should not be any perceptible vibration of the stack. The whole mechanism of Make/ Break shall conform to stringent quality control of production. The rated peak withstand current and the rated short time withstand current, carried by an isolator in the closed position during the rated duration of short circuit, shall not causei) Material mechanical damage to any part of the isolator. ii) Separation of the contacts iii) A temperature rise that added to the maximum temperature obtained when carrying the rated normal current continuously, is likely to damage the insulation. After the passage of these currents, the isolator shall be able to carry its rated normal current without its temperature rise exceeding the values specified in IS:9921.

3.3.2 36 KV Isolator Operation shall be easy for any normal person without much effort and the torque required should not be more than 30 kg-meter. The mechanism shall ensure simultaneous and identical operation of the three poles. All bearings shall be heavy duty,

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

52

lubricated for life and sealed against dust and moisture.

3.4

Motors

Operating motors shall be totally enclosed, weather proof, outdoor type insulated for tropical service and suitable for continuous operation on 415 ±10%, 3 phase, 50 Hz, A.C. supply. Motor starters shall be automatic contactor, direct-on line type fitted with magnetic/thermal overload trip devices and HRC fuses. The motors should be electrically reversible type with high starting torque. Motor space heaters at 240 ± 10% single phase, 50 Hz are also to be provided.

3.5

Contacts

Contacts shall be high-pressure self-aligning, self-cleaning adjustable type made of corrosion resistant hard drawn electrolytic copper. Full contact and current carrying capacity shall be secured with a lateral travel allowance. The high pressure type contacts shall wipe the contact surface while opening and closing. The contacts shall be so designed that wiping action shall not cause scouring and abrasion on the contact surfaces. The wiping action shall be sufficient to remove any film of oxide which may be formed during the operation of the switches.

3.6

Switch blade & Jaws

The switch blades shall be corrosion resistant of hard drawn electrolytic copper and capable of withstanding all conditions of operation including specified short circuits without distortion. Fixed guides wherever necessary should be provided. The switch contacts shall be capable of isolating power transformers generators and overhead lines at no load from the system and also be capable of interrupting charging current mentioned earlier. All movable parts in the current path shall be shunted by flexible copper conductors of sufficient length to prevent breaking due to repeated closing.

3.7 Operating kiosk Shall be made of sheet steel of thickness not less than 2mm. Weather and dust protected control cabinet shall be provided for housing the operating motor control equipment and interlocks for the mechanism. The degree of protection shall be IP - 55. All wiring for the motor and associated controls shall be terminated in this cabinet. It shall be complete with hinged door and padlock with duplicated keys, thermostat controlled space heaters, cubicle light switch, utility outlets and cable terminal glands for the Purchaser’s cables. The equipment to be supplied with the control cabinet shall include the following : 1. Supply cut-off switch backed up by air circuit breakers. 2. Push button reversible starters with magnetic thermal over load tripping device for the motors. 3. Local/ remote change over switches. 4. Auxiliary switch contacts. 5. One utility outlet for hand lamps. 6. Necessary terminal blocks with ten percent spare terminals. 7. Cable glands for PVC armoured cables. The wiring in the control cabinet near the isolators shall be made with 1100V grade, PVC insulated copper conductors. It shall be grouped, cleated and finished at numbered terminal blocks with cable lug type terminals and numbered terminal ferrules the space

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

53

heater connections shall be insulated with porcelain beads over a safe distance.

3.8

Auxiliary switches

Sixteen, single pole, auxiliary contacts, which can be adjusted to be in the normally close or normally open position as required shall be furnished in the case of 245 KV and 145 KV isolators. Six, single pole, auxiliary contacts which can be adjusted to be in the normally close or normally open position as required shall be furnished in the case of 36 KV isolators. For earthing switch, six auxiliary contacts are to be supplied. The contact rating shall be at least 10 Amps. As per IS:9921(Part-III).

3.9

Interlocks

Interlock shall be provided to prevent the isolator the being operated on load i.e. opening and closing of isolator can be done only when the circuit breaker is open. Manual operation of isolator shall only be possible when the breaker is open and the supply to control circuit for isolator operation is off (handle interlock). Interlock shall also be provided so that electrical operation of the isolator from local/ remote is only possible when the operating handle for manual operation is not in use. The isolator should be manually operable in case of aux. supply failure. Pole discrepancy shall provided for a 245 KV and 145 KV isolators with single units operated as one unit for 3-phase operation. Earth switches wherever provided shall be mechanically and electrically interlocked so that they can be operated only when the isolator is opened or vice versa.

3.10

Insulators

Solid core insulators are to be used for 245 KV and 145 KV isolators. Pedestal post type insulators are to used for 36 KV isolators. The details are indicated in the respective specifications for solid core and pedestal post insulators.

3.11

Arching Horn

Suitable adjustable arcing horns made of tinned electrolytic copper or G.I. shall be provided on the contacts where required.

3.12

Protective Coatings

All ferrous parts shall be corrosion protected by hot dip galvanized to conform to IS:2633 or equivalent. All non-ferrous fasteners should be heavily tinned.

4

Operational Requirements

Isolators and earth switches shall be capable of withstanding the dynamic and thermal effects of the maximum possible short circuit of the system in the closed position. The earth switches wherever provided shall be interlocked so that they can be operated only when the isolator is open. The earthing switch shall be capable of discharging trapped charges of the associated lines. Isolators and earth switches shall have provision to prevent their electrical and manual operation unless the associated interlocking conditions with other equipment in the bay are met. All these interlocks shall be of fail safe type. The isolators and earth switches shall be able to bear on the terminals the total forces on the attached conductor without impairing reliability or current carrying capacity.

5

Material & Workmanship

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

54 All materials used in the manufacture of the equipment shall be new and shall conform to requisite design features like strength durability etc. Liberal factors of safety shall be used throughout the design and specially in the design of all parts subject to alternating stresses or shocks. Casting shall be free from blowholes, flaws, cracks or other defects and shall be smooth close grained and of true forms and dimensions. No plugged or filled up holes or other defects will be normally allowed.

6

Tests

Operation of the isolators shall be tested at manufacturer’s works. Demonstration at site also is to be carried out by supplier’s representative. Tests shall be made in accordance with the indicated standards. The following are the minimum tests required to be carried out on the offered isolators.

6.1

Type Tests

Complete Type Test Reports from NABL accredited laboratory / Equivalent laboratory aboard shall be submitted along with the offer. The following constitute the type tests: 1. Lightning Impulse voltage dry tests. 2. Power frequency voltage dry tests on main circuits. 3. Power frequency voltage wet tests on main circuits. 4. Power frequency voltage on auxiliary equipment. 5. Temperature rise on main circuits and auxiliary equipment. 6. Test to prove the capability of carrying the rated peak short circuit current and rated short time current. 7. Satisfactory Operation and Mechanical endurance test.

6.2

Routine Tests

The following constitute the routine tests: 1. Power Frequency voltage dry tests of the main circuit 2. Voltage test on the control and auxiliary circuit 3. Measurement of resistance of the main circuit 4. Mechanical operation test 5. Temperature rise test on main circuit.

6.3

Acceptance Tests

Each completely assembled unit shall be operated at least fifty times and all adjustments made before dispatch. All routine tests constitute the acceptance tests also.

7

Documentation

The following shall constitute the documentation required for the specified equipment. The submission and approval procedure is indicated in the SCC. 1

General outline and dimensioned drawings depicting the net and shipping weights.

2

Detailed drawings of the operating mechanism, auxiliary switches, earthing switches etc.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

55

3

Detailed drawings of the contact assembly.

4

Detailed drawings of terminal pad where the connector is to be mounted.

5

Detailed diagrams of the interlock schemes.

6

Details of mounting for the isolators.

7

Schematic and detailed wiring diagrams for the motor control circuit.

8

Arrangement drawing of the operating kiosk.

9

Fixing details of the base on structure.

10

Earth operating mechanism and foundation details.

11

Foundation details of operating mechanism.

12

Fixing details of earth operating mechanism with base channels.

13

Instruction manual for erection, operation and maintenance.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

56

8

Specific Requirements ISOLATORS

Sl.

Parameter

Value

1

2

3

245 KV ISOLATOR 1 Rated voltage 2 Number of poles 3 Type 4 Rated normal current a For terminal height 5.75M & phase spacing 4M b For stringing height 10.5M & phase spacing 4M 5 Rated frequency 6 Rated short time current(rms) 7 Rated peak withstand current 8 Type of Break 9 Basic Insulation level 1.2/50 microsec Impulse test voltage (KVp) To earth and between poles a Across the isolating distance b 10 One minute power frequency withstand voltage (KVrms) a To earth and between poles b Across the isolating distance 11

Operating mechanism

12 13 14 15 16

Interlock Temperature rise of current carrying parts Short time rating Mechanical Terminal Load Earthing Switch

17 18 19 20

245 KV Three As per spec. 1250A 2000A 50 Hz 40kA for 1sec 100 kA Double, horizontal

1050 1200 460 530 Motor operated, one unit for each pole. Control voltage 415 V, AC, 50Hz

Electrical As per IS:9921 As per IS:9921 As per IS:9921 Independent manual drive mechanically interlocked with main blades. Mounting Horizontal upright with horizontal break. Minimum clearance for isolator between phase and earth 2208mm Maximum charging current to be interrupted 2 Amps Insulators Solid core post type as per spec.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

57

Sl.

Parameter

Value

1

2

3

145 KV ISOLATOR 1 2 4 5 a b 6 7 8 9 10 a b 11 a b

Rated voltage Number of poles Type Rated continuous current For terminal height 5.3M & phase spacing 2.7M For stringing height 9M & phase spacing 2.7M Rated frequency Rated short time current Rated peak withstand current Type of Break Basic Insulation level 1.2/50 microsec Impulse test voltage (KVp) To earth and between poles Across isolating distance One minute power frequency withstand voltage (KVrms) To earth and between poles Across isolating distance

12 a

Operating Mechanism Tandem type

b

13 14 15 16 17 18 19 20

145 KV Three As per spec. 1250A 2000A 50 Hz 40 KA for 3 secs. 100 kA Double, horizontal

650 750 275 315

Motor operated, one unit for each pole Motor operated, 3 phases Normal type mechanically ganged, Control voltage 415 V, AC, 50Hz Interlock Electrical As per IS:9921 Temperature rise of current carrying parts Short time rating As per IS:9921 Earthing Switch Independent manual drive mechanically interlocked with main blades. Mounting Horizontal upright with horizontal break. Minimum clearance for isolator between phase and earth 1472mm Maximum charging current to be interrupted 2 Amps Insulators Solid core post type as per spec.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

58

Sl.

Parameter

Value

1

2

3

36 KV ISOLATOR 1

Rated voltage

36 KV

2

Number of poles

Three

3

Type

As per spec.

4

Rated continuous current

a b 5 6 7 8 9 a b 10 a b 11

For terminal height 4M & phase spacing 1.5M For stringing height 6.75M & phase spacing 1.5M Rated frequency Rated short time current(rms) Rated peak withstand current Type of Break Basic Insulation level 1.2/50 microsec Impulse test voltage (KVp) To earth and between poles Across isolating distance One minute power frequency withstand voltage (KVrms) To earth and between poles Across isolating distance Operation

12 13 14 15

Interlock Temperature rise of current carrying parts Short time rating Earthing Switch

16

Mounting

1250A 2000A 50 Hz 25kA for 3 secs 62.5 kA Double, horizontal

170 195 70 80 Manual, three phase mechanically ganged Electrical and mechanical As per IS: 9921 As per IS: 9921 Independent manual drive mechanically interlocked with main blades.

17

Horizontal upright with horizontal break. Minimum clearance for isolator between phase and earth 508mm

18 19

Maximum charging current to be interrupted Insulators

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

2 Amps Pedestal post type as per spec.

59

SPECIFICATION FOR INSTRUMENT TRANSFORMERS DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1 Scope This specification cover the design, manufacture, testing at manufacture’s works, packing for road transportation and delivery at site of 220 KV, 132 KV, 33 KV outdoor type current transformers and 220KV/√3 110V/√3,132KV/√3 110V/√3,33KV/√3 110V/√3 outdoor type, electromagnetic potential transformers for relaying and metering purposes in 220 KV,132KV solidly grounded and 33KV ungrounded system. The Current and Potential transformers shall be complete with all accessories including secondary terminal boxes.

/

/

/

Current transformer shall hereinafter be referred to as CT and potential transformer as PT.

2

Standards

The equipment covered by this specification shall conform in all respect to the latest version of the following standards: • IEC : 60044-1 • IS : 2705(Part I, II, III, IV) • IS : 5621-Specification of Hollow Insulators for Use in Electrical Equipment. • IEC : 60044-2 • IS : 3156 (Parts I,II,III) Wherever the stipulation in this specification are at variance with the standard, the stipulations made herein shall be binding.

3

System Data

220 KV and 132KV systems are effectively earthed. 33 KV system is Grounded through ZigZag Star Grounding Transformer. The system frequency is 50 Hz. The three-phase unit vector rotates anti-clockwise in the order - Red - Yellow - Blue - Red.

4

Construction

The outdoor type single phase current transformers shall be of Dead tank design for 220 KV and 132 KV CT and of dead / live tank design for 33 KV CT. The design and construction

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

60 shall be such as to enable ease of handling during repair and maintenance ‘at site’. The CT shall be structurally stable. The common features shall be as follows:

4.1

Tank and Fittings

All 220 KV and 132KV instrument transformers shall be hermetically sealed. Nitrogen may be used for hermetic sealing. The tank as well as other metallics exposed to the atmosphere may be hot dip galvanized or painted and shall be designed to withstand internal pressures developed due to symmetrical short circuit values stated elsewhere in this document. The tank shall be hydraulically tested for oil tightness and all cover seals flanges joints, threaded connections and pipe- fittings shall be properly machined and provided with gaskets where necessary to ensure oil tight fitting. Compensation arrangements for oil volume variation in tank shall be ensured. The tank shall be fitted with oil sight gauges and cocks for convenient filling and draining of oil. Pressure relieving device capable of releasing abnormal internal pressures should also be provided. The bushing shall be of oil filled porcelain type suitable for outdoor use and mounted upright on Steel Structure. The porcelain shall be made by wet process, and shall be homogeneous thoroughly vitrified and impervious to moisture. The glazing shall be uniform brown color, free from blisters, burns and other similar defects. The oil filled bushing shall have ample insulation and mechanical strength for the duty involved and shall be designed to prevent accumulation of explosive gases and to provide adequate oil circulation to remove internal heat. There shall be no undue stressing due to temperature changes and adequate means shall be provided to accommodate conductor expansion. The Bushing should conform IS 5621. The insulation of the bushing shall be co-ordinated with that of the current transformer such that the flash-over will occur externally.

4.2

Mounting

The Instrument Transformers shall preferably have universal base for mounting on steel structures.

4.3

Connectors for earthing

Suitable connectors for earthing connections of the equipments to ground bus shall have to be supplied with the equipment. Each current transformer shall have two grounding pads.

4.4

Secondary Terminal Box

The secondary terminals shall be housed in a weather proof chamber for receiving Purchaser’s PVC insulated, PVC sheathed, armored power / control cables. The number of opening in the tank for bringing out tapping should be kept to a minimum. The secondary terminal compartment shall have a removable cover. The terminal box, with the cover closed and tightened and the cable/conduit in position when supplied shall have degree of protection conforming to IP 55 of IS : 13947, Part-1.The secondary terminals of CT shall be suitable for lugs of 6 sq.mm. Copper for 1A secondary and 10 sq.mm. for 5A secondary. In the case of 220 KV and 132KV CTs, the primary winding power factor tap shall also be terminated in the secondary terminal box through proper bushing.

4.5

Terminals

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

61 CT primary terminals shall be made of Copper. PT primary terminals shall be made of non-ferrous corrosion resistant material.

4.6

Painting

All interiors or exteriors of tanks, secondary box and other metal Parts shall be thoroughly cleaned to remove all rust, scales, corrosion, grease or other adhering foreign matters. All steel surfaces in contact with insulating oil as far as accessible shall be painted with not less than two coats of heat resistant oil insoluble insulating varnish. Steel surface exposed to the atmosphere if not hot dip galvanized shall be given a priming coat of Zinc Chromate and two coats of light grey paint. All metal parts not accessible for painting shall be made of a corrosion resisting material. All machine finished or bright surfaces shall be coated with a protective compound and suitably wrapped or otherwise protected. All points shall be carefully selected to withstand tropical heat and extreme weather conditions. The paint shall not scale off or crinkle or be removed by abrasion due to normal handling and for a reasonable period of life.

4.7

Name Plate and Markings

Each current transformer shall carry rating and diagram plate giving particulars as per IS 2705. The terminal markings shall also be in according with the specification mentioned above.

4.8

Oil

The oil shall be un-inhibited conforming to IS-335.

5

Instrument Specific Features

Apart from the above constructional requirements each type of instrument transformer shall comply with the following additional features:

5.1

Current transformer

The current transformers shall have a ring type or hair pin type primary designed in such a manner as to bring of the secondary terminals in a weather proof terminal box at the bottom. The secondary terminals shall be terminated to stud type terminals inside the terminal box.

5.1.1 Temperature Rise The temperature rise of current transformer winding when carrying continuous thermal current at rated frequency with rated output shall not exceed the following values above the specified ambient: • 40oC in all parts by thermometer • 45oC in the winding by resistance

5.1.2 Core Construction The core shall be of high grade, non-aging, electrical silicon laminated steel of low hysteresis loss and high permeability to ensure high accuracy at both normal and overcurrent. The core shall be mechanically strong and all core-clamping bolts shall be effectively insulated. The core to be used for metering and instrumentation shall be of accuracy class specified. The saturation factor of the core shall be low enough not to cause any damage to measuring instruments in the event maximum short circuit current. Tariff metering cores shall be made of mumetal.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

62

Cores to be used for protective relaying purpose shall be of accuracy class specified.

5.1.3 Windings Primary shall be made of Copper only. Cross-section of the winding shall be chosen to suit the specified continuous and short-time current carrying capacity .The different ratios specified shall be achieved by secondary taps only and primary reconnection shall not be accepted in any case. The rating of the secondary windings shall be as indicated in the design requirements. The secondary terminals shall be provided with short circuiting arrangements. The secondary taps shall be adequately reinforced to withstand normal handling without damage.

5.1.4 Protective device Secondary protective device shall be provided, if necessary.

5.1.5

Insulation

The current transformer shall withstand satisfactory the dielectric test voltages corresponding to basic insulation level of 1050 KVp, 650 KVp and 170KVp for 220 KV, 132 KV and 33 KV C.T.s respectively.

5.2

Potential transformers

The potential transformer shall be outdoor porcelain type, oil immersed self cooled, single pole, single phase, electromagnetic type for 220 KV and 132KV effectively earthed system and 33 KV non-effectively earthed system. PT shall be conforming to IS : 3156 in all respect. PT shall be used as potential source to protective relays, indicating instruments, tariff metering equipment and for obtaining voltage reference for synchronizing purpose. Primary & Secondary winding shall be made of Copper only.

5.2.1 Temperature Rise The temperature rise of voltage transformer at the specified voltage, rated frequency and rated burden at any power factor between 0.8 lagging and unity shall not exceed the following values above the specified ambient: • 40o in oil by thermometer. • 45o winding by resistance. • 55o of winding by resistance at rated voltage factor. The voltage transformer shall be designed to prevent accumulation of explosive gases and to provide adequate oil circulation to remove internal heat. There shall be no undue stressing due to temperature changes and adequate means shall be provided to accommodate conductor expansion. The bushing should conform to IS : 5621.

5.2.2 Core Construction The core shall be of non-ageing silicon laminated steel of the highest quality. Laminations shall be coated on one side with approved insulating materials and shall be inter-leaved. The core shall be mechanically strong and all core clamping bolts shall be effectively insulated. The core shall be so designed that no saturation takes place when 1.73 times normal voltage is applied to the windings for a period of 15 minutes.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

63

5.2.3 Winding The Primary VA capacity should be sufficient to deliver the summation of rated burdens of all secondary windings. The Potential Transformer Core to be used for metering and instrumentation shall be of specified accuracy class as per IS : 3156. The PT core to be used for protective relaying purpose shall be of specified accuracy class as per above mentioned IS.

5.2.4

Insulation

The PT shall withstand satisfactorily the dielectric test voltage corresponding to basic insulation level of 1050 KVp, 650 KVp and 170 KVp for 220 KV, 132 KV and 33 KV voltage levels respectively.

6

Tests

6.1

Current Transformers

6.1.1 Type Tests Complete Type Test Reports on each type of current transformer shall be submitted with the offer as per IS 2705 / IEC 60044-1 from NABL accredited laboratory / Equivalent laboratory aboard. The following constitutes the type tests : 1. Short time current test. 2. Temperature Rise test. 3. Lightning Impulse test. 4. High voltage power frequency wet withstand voltage test. 5. Determination of errors and other characteristics specific to a particular accuracy class.

6.1.2 Routine Tests The following constitutes the routine tests: 1. Verification of terminal markings and polarity. 2. Power frequency dry withstand tests on primary winding. 3. Power frequency dry withstand tests on secondary windings. 4. Over-voltage inter turn test. 5. Partial discharge tests as per IS 11322/IEC 60270 (on CTs with highest system voltage level of 72.5 KV and above). 6. Determination of errors and other characteristics specific to a particular accuracy class.

6.1.3 Acceptance Tests

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

64

All tests indicated in the list of routine tests shall constitute the acceptance tests. In addition to the above, Temperature Rise Test shall be carried out on one CT of each lot offered for inspection. The tests shall be carried out in the presence of Purchaser’s representative if so desired by the Purchaser. All test reports should be submitted and subsequently got approved in writing from the Purchaser before dispatch of the equipment is effected.

6.2

Potential Transformer

6.2.1 Type Tests Complete Type Test Reports for each type of potential transformer shall be submitted with the offer as per IS 3156 / IEC 60044-2 from NABL accredited laboratory / Equivalent laboratory aboard. The following constitutes the type tests : 1. Temperature-rise test 2. Short-circuit withstand capability test –as per IEC 60044-2 (optional-as per Purchaser opinion) 3. Lightning impulse test 4.

High voltage power frequency wet withstand test.

5. Determination of errors and other characteristics specific to a particular accuracy class.

6.2.2 Routine Tests The following constitutes the routine tests: 1.

Verification of terminal markings and polarity.

2.

Power frequency dry withstand tests on primary winding.

3.

Power frequency dry withstand tests on secondary windings.

4.

Over-voltage inter turn test.

5.

Partial discharge tests as per IS 11322/IEC 60270

6. Determination of errors and other characteristics specific to a particular accuracy class.

6.2.3 Acceptance Tests All tests indicated in the list of routine tests shall constitute the acceptance tests in the presence of Purchaser’s representative if so desired by the Purchaser. All test reports should be submitted and subsequently got approved in writing from the Purchaser before dispatch of the equipment is effected.

7

Documentation

The following shall be submitted: 1. Detailed dimensional drawings and drilling plan, list of fittings and details of terminal pads, net weight of the instrument transformer complete with oil and fittings and weight and volume of oil. 2. Diagram of connections, name plate and rating plate.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

65

3. Sectional view showing internal arrangement of Core and Windings and connections. 4. Magnetisation curve and other electrical data. 5. Manuals if any. The number of copies required and procedure for submission are indicated in the SCC.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

66

1 Specific Requirements 220 KV Current Transformer Sl.

Parameter

Type 1

Type 2

1

2

3

4

1 2 3

Nominal System Voltage in KVrms Highest System Voltage in KVrms Lightning Impulse withstand voltage in KVp One minute power frequency wet withstand voltage in KVrms Rated frequency in Hz Rated short time current for 1 sec in kA Rated dynamic current in kAp Rated primary current in Amps. Rated continuous thermal current in Amps. Rated secondary current in A Minimum creepage distance (phase to ground) in mm Class of insulation One minute power frequency withstand voltage between secondary terminal and earth in KVrms Partial discharge level Type Extended current rating Core Ratio Class Minimum knee point voltage (Vkp) Excitation Current (Iex) Rct

220 245 1050

220 245 1050

460

460

50 40 100 800 960 1-1-1

50 40 100 800 960 1-1-1

6125

6125

A

A

3

3

10pC max Dead tank 120% (for Core-3) Core 1 800-400/1A PS ≥ 1600/800V

10pC max Dead tank 120%(for Core-3) Core 1 800-400/1A PS ≥ 1600/800V ≤ 15/30 mA at Vkp/4 ≤ 10/5 ohms Core 2 800-400/1A 5P 20 Core 3 800-400/1A 0.2 ≤ 5 15/10 VA

4 5 6 7 8 9 10 11 12 13 14 15 16 17 17a 17b 17c 17d 17e 18 18a 18b 18c 18d 18e 18f 19 19a 19b 19c 19d

Ratio Class Minimum knee point voltage(Vkp) Excitation Current (Iex) Rct ALF Ratio Class ISF Burden

≤ 15/30 mA at Vkp/4 < 10/5 ohms Core 2 800-400/1A PS ≥ 1600/800V ≤ 15/30 mA at Vkp/4 < 10/5 ohms Core 3 800-400/1A 0.2 ≤ 5 15/10 VA

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

67

220 KV Electromagnetic Potential Transformer Sl.

Parameter

Type 1

Type 2

1

2

3

4

1

Nominal System Voltage in KVrms

220

220

2

Highest System Voltage in KVrms

245

245

3

Lightning Impulse withstand voltage in KVp

1050

1050

275

275

50 1.2 continuous 1.5 for 30 secs A

50 1.2 continuous 1.5 for 30 secs A

6125

6125

3

3

10pC max Dead tank ≤ 1.4 Winding 1 220KV/√3 110V/√3 3P 100 VA Winding 2 220KV/√3 110V/√3 0.2 50 VA Winding 3 220KV/√3 110V/√3 0.2 50 VA

10pC max Dead tank ≤1.4 Winding 1 220KV/√3 110V/√3 0.2 50 VA -

5

One minute power frequency wet withstand voltage in KVrms Rated frequency in Hz

6

Rated voltage factor

7

Class of Insulation Minimum creepage distance (phase to ground) in mm One minute power frequency withstand voltage between secondary terminal and earth in KVrms Partial discharge level Type Earth fault factor

4

8 9 10 11 12 13 13a

Ratio

13b 13c 14

Class Burden

14a

Ratio

14b 14c 15

Class Burden

15a

Ratio

15b 15c

Class Burden

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

-

68

SPECIFICATION FOR LIGHTNING ARRESTERS DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1

Scope

This specification covers the design, manufacture, testing and supply of 198 KV, 120 KV, 36 KV heavy duty station class Zinc Oxide gapless Lightning Arresters for 220 KV, 132 KV AC neutral grounded and 33 KV AC ungrounded system complete with insulating base, surge monitors, surge counters, current meters and other connecting accessories.

2

Standards

The equipment shall conform to the latest edition of the following standards: 1.

IEC 60099-4, Metal-oxide surge arresters without gaps for A. C. systems.

2.

IS : 3070(Part-III) - Metal-oxide surge arresters without gaps

Wherever the stipulations in this specification are at variance with the standards, the stipulation made herein shall be binding.

3

System Data

• Nominal System Voltage (KV rms)

- 220 / 132 / 33 KV.

• Highest system voltage (KV rms)

- 245 / 145 / 36 KV.

• No. of Phases

- 3.

• Operating frequency (Hz)

- 50.

• System neutral connection

- a) 220 KV and 132 KV - solidly earthed b) 33 KV - earthed through a grounding transformer

• Isocraunic level

- 70.

• Shielding

- Overhead ground wires provided.

• Shield angle

- 30.

• B.I.L. of the equipment to be protected (KVp) - 1050 KVp for 245 KV system, 650 KVp for 145 KV system and 170 KVp for 36 KV system.

4

Construction

Construction requirements shall conform to Section 5 of IEC 60099-4.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

69

All cemented and detachable ferrous hardware shall be hot dip galvanised. Galvanising shall conform to IS:2629. Each Lightning Arrestor shall be complete with all fittings and accessories like grading rings, discharge counter, leakage current detector, connecting conductor, clamp type terminal connectors, porcelain base, two (2) clamp type ground terminal connectors suitable for G.I. Strip (50mm x 6mm) and necessary hardware such as nuts, bolts, spring washers etc. with 20% spare hardware.

5

Tests

Type Test -

Complete Type Test Reports for each type of Lightning Arresters shall be submitted with the offer as per IEC 60099-4 from NABL accredited laboratory / Equivalent laboratory aboard.

The design test shall include ‘Radio interference’ on the complete arrester. Routine Test -

Routine tests as stipulated in IEC 60099-4 shall be carried out by the manufacturer on all complete arrestors and also on each section as per their standard practice. The resistive current drawn by the arrestor at rated voltage shall be indicated in the routine test report. A schedule of the standard tests carried out by the manufacturers shall be submitted along with the tender.

Acceptance Test - All acceptance tests stipulated in IEC 60099-4 shall be performed during inspection to be carried out by the Purchaser’s representative.

6

Documentation

Documentation shall include the following: 1. Dimensioned drawing of complete arrester and fixing details. 2. Sectional view of the arrester. 3. Diagram of minimum clearances in relation to adjacent grounded metallic structures. 4. Dimensioned drawing of terminal and ground connector giving details of materials used. 5. Dimensioned drawing of the surge monitor and counter and current meter. 6. Dimensioned drawing of the insulating base.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

70

7

Tender Specific Requirements

The specific technical requirements for lightning arresters are as follows: LIGHTNING ARRESTERS Sl. Instrument 198KV LA 1 Type of installation 2

Arrester type and class

3 4 5 6

Rated voltage in KV Maximum continuous operating voltage at 50 oC (MCOV) Nominal discharge current in kA with 8/20 µsec wave Insulation withstand voltage (Dry, Wet and Impulse)

7

Steep current impulse residual voltage at 10 KA of 1 µsec front time Lightning Impulse residual Voltage (KVp) (8x20 µsec wave)

8

i)

5000 A

Value

Outdoor, pedestal mounted Metal oxide, heavy duty, gapless, single column, single phase, station class 198 168KV 10 Test as per IEC 60099-4 Test as per IEC 60099-4 Test as per IEC 60099-4

ii) 10000 A 8 9

iii) 20000 A Long duration discharge class Switching impulse withstand voltage of arrester

10 11

High current impulse withstand value (4x10 µsec) Pressure relief rated current i) High Current ii) Low Current 12 BIL(KVp) 13 Minimum creepage distance 120 KV LA

Class 3 Test as per IEC 60099-4 100kA peak As per IEC 60099-4

1050 25mm/KV

1

Type of installation

Outdoor, pedestal mounted

2

Arrester type and class

3 4 5

Rated arrester voltage in KV Maximum continuous operating voltage at 50 oC (MCOV) Nominal discharge current in KA with 8/20 µsec wave

Metal oxide, heavy duty, gapless, single column, single phase, station class 120 102 KV 10

6

Insulation withstand voltage (Dry, Wet and Impulse)

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

Test as per IEC 60099-4

71

Sl.

Instrument

Value

7

Steep current impulse residual voltage at 10 KA of 1 µsec front time

Test as per IEC 60099-4

8

Lightning Impulse residual Voltage (KVp) (8x20 µsec wave)

Test as per IEC 60099-4

i)

5000 A

ii) 10000 A iii) 20000 A 9

Long duration discharge class

Class 3

10

Switching impulse withstand voltage of arrester housing

Test as per IEC 60099-4

11 12

100 KA peak As per IEC 60099-4

13

High current impulse withstand value (4x10 µsec) Pressure relief rated current iii) High Current iv) Low Current BIL (KVp)

14

Minimum creepage distance

25mm/KV

36 KV LA 1 Type of installation

650

Outdoor, pedestal mounted Metal oxide, heavy duty ,gapless, single column, single phase, station class

2

Arrester type and class

3 4 5 6

Rated arrester voltage in KV Maximum continuous operating voltage at 50 oC (MCOV) Nominal discharge current in KA with 8/20 µsec wave Insulation withstand voltage (Dry, Wet and Impulse)

36 30 KV 10 Test as per IEC 60099-4

7

Steep current impulse residual voltage at 10 KA of 1 µsec front time Lightning Impulse residual Voltage (KVp) (8x20 µsec wave)

Test as per IEC 60099-4

i)

Test as per IEC 60099-4

8

5000 A

ii) 10000 A iii) 20000 A 9

Long duration discharge class

Class 3

10 11 12

As per IEC 60099-4 100 KA peak As per IEC 60099-4

13

Switching impulse withstand voltage of arrester housing High current impulse withstand value (4x10 µsec) Pressure relief rated current v) High Current vi) Low Current BIL (KVp)

14

Minimum creepage distance

25 mm/KV

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

170

72

SPECIFICATION FOR LT (FRLS) CABLES DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1 Scope The specification covers design, engineering, manufacture, testing at the manufacturer’s works and delivery of the following: 1. AL. CONDUCTOR (FRLS TYPE) : 1.1 KV (E) circular/shaped stranded Aluminium conductor, extruded PVC insulated, extruded PVC innersheated, GI. round/flat armoured, overall served with PVC suitably compounded to ensure specified fire retardant low smoke properties, heavy duty power cable conform to IS:1554(Pt.I) and meeting type and special test requirements detailed herein. 2. CU. CONDUCTOR (FRLS TYPE) : 1.1 KV (E) stranded plain (untinned) annealed high conductivity copper conductor, extruded PVC insulated, extruded PVC innersheathed, Single layer GI round/ flat armoured, overall served with PVC suitably compounded to ensure specified fire retardant low smoke properties, heavy duty control cable conform to IS : 1554 (Pt. I) and also meeting type and special test requirements detailed herein.

2 Standards Cables specified in this specification shall conform to latest version of the following International/Indian standards. 1. IS:3961

-

2. IS:1554 (Pt. I) upto

Recommended current ratings for cables. PVC insulated (heavy duty) electric cables for working voltages and including 1100 V.

3. IS:5831

-

PVC insulation and Sheath of electric cables.

4. IS:8130

-

Conductors for insulated electric cables and flexible cords.

5. IS:3975

-

Mild steel wires, strips and tapes for armouring of cables.

6. IEC 60811

-

Common test methods for insulating and sheathing materials of electric cables and optical cables

7. IEC 60332

- Tests on electric and optical fibre cables under fire conditions (all relevant parts)

8. IEC 60331

-

Tests for electric cables under fire conditions (all relevant parts).

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

73

9. IEC 60754

-

Test on gases evolved during combustion of materials from cables – Part 1: Determination of the amount of halogen acid gas Part 2: Determination of degree of acidity of gases evolved during the combustion of materials taken from electric cables by measuring pH and conductivity.

10. IS:694

-

PVC insulated cables for working voltages upto and including 1100 V.

If any better standards other than those specified above are adopted than the same shall be stated and latest revision of the English version of the same shall be submitted. The performance and operation of the equipment in such case shall be equal to or better than the specified standards.

3 Operating Conditions Cables shall be used for rated system voltages 415 V / 240 V (neutral solidly grounded), 50 Hz, AC and 220 V / 250 V DC. Voltage variation shall be ± 20%. Frequency variation shall be ± 5%. Combined voltage and frequency variation shall be ± 10%. For purpose of this specification ambient temperature shall be 50 oC peak and 45 oC average.

4 Design Requirements 4.1

Aluminium Cables (FRLS)

1. Designation : 1100 V (E) grade, multi-core, Aluminium conductor, PVC insulated, GI flat/round armoured overall served with PVC suitably compounded to ensure specified fire retardant low smoke properties heavy duty power cable. 2. Reference : IS 1554 (Pt. - I); IS 8130; IS 5831; IS 3975, other applicable standard and test requirements as subsequently specified. 3. Conductor : Compact circular/sector shaped stranded H2 or H4 Aluminium conductor Class 2 Table 2 of IS:5831. 4. Insulation : PVC Type-A, to IS 5831. 5. Innersheath & filler : PVC Type ST-1 of IS 5831. Inner sheath shall be extruded. 6. Armouring : GI Wires/Strips to IS 3975 and IS 1554 (Pt. - I). 7. Outer sheath : PVC type ST-1 to IS 5831 suitably compounded for FRLS properties and with suitable additives to prevent attack by rodents and termites and passing test requirements specified here in after. 8. Factory test : As specified hereinafter.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

74

4.2

Copper Cables (FRLS)

1. Designation : 1100 V (E) grade, multi-core copper conductor, PVC insulated GI flat/round armoured, overall served with PVC suitably compounded to ensure specified fire retardant low smoke properties heavy duty control cable. 2. Reference : IS 1554 (Pt. I); IS 8130; IS 5831; IS 3975, other applicable Standard and test requirement as subsequently specified. 3. Conductor : Standard plain ( untinned) annealed high conductivity copper conductor Class 2 table 2 of IS 8130. 4. Insulation : PVC Type-A of IS 5831. 5. Innersheath and filler : PVC Type ST-1 of IS 5831. Inner sheath shall be extruded. 6. Outer sheath : PVC type ST-1 of IS 5831 suitably compounded for FRLS properties and with suitable additives to prevent attack by rodents and passing test requirements specified hereinafter. 7. Armouring : GI Wire/strips to IS 3975 and IS 1554 (Pt. I). 8. Factory test : As specified hereinafter.

5

Identification Marks

Throughout the length, cables served with FRLS PVC outer sheath shall be identified by surface marking by embossing/ machine printing giving : 1. Name of manufacturing and year of manufacture: 2. Cable description e.g. 1100 V 4C x 10.0 Sq. mm Cu PVC FRLS Type cable etc. 3. Name of customer e.g. CUSTOMER: DVC 4. Embossed length measure in Meters at every meter interval. 5. Core identification shall be done by colours as per IS 1554 (Pt. I).

6 Drumming, Reeling & Marking The cables shall be supplied in non-returnable wooden drums in 500M ± 5% reel lengths for power cables and 1000M ± 5% for control cables unless otherwise specified. The cable drums shall be suitable for taking round spindle and shall be suitably logged with strong 5cm thick wooden battens so as to prevent damage to the cable. A minimum clearance of 15cm shall be allowed between the outer layer and the inside of logging. Cable ends shall be properly sealed and made water tight so as to prevent ingress of moisture during transit/storage in the open cable yard. The drums shall be suitably reinforced with hoop iron to withstand transit hazards. Each drum shall have a distinguishing number. On outside of the flange particulars of the cable viz. voltage class, length, cable description, project reference and order details, finished gross weight and net weight and direction of reeling shall be clearly stated on the flange of the drum. The wooden drum shall conform to latest IS. Non-standard lengths are not acceptable.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

75

7 Tests Following type tests including special tests, acceptance and routine tests as per requirements of relevant standards mentioned shall be carried out on conductors, cores and finished cables in the works premises of the manufacturer.

7.1

Type tests

Complete Type Test Reports shall be submitted with the offer as per the indicated standards from NABL accredited laboratory / Equivalent laboratory aboard.The test of one drum out of every 10 drums or less on each type and size of the cable shall be conducted as per IS:10418. A)

Test on Conductor

1. Tensile test (for Aluminium)

: As per IS 8130.

2. Annealing test (for Copper)

: As per IS 8130.

3. Wrapping test (for Aluminium)

: As per IS 8130.

4. Conductor resistant test ( for Aluminium and Copper) :

As per IS 8130.

B) Test for armouring wires

:

As per IS 3975.

C) Test for thickness of insulation and sheath

:

As per IS 1554(Pt.I)

D) Physical test for insulation and outer sheath

:

As per IS 5831

:

As per IS 5831

a) Tensile strength and elongation at break b) Ageing in air oven c) Shrinkage Test d) Hot deformation e) Loss of mass in air oven f) Heat Shock Test g) Thermal Stability h) Cold Bend Test (for diameter ≤ 12.5 mm) i) Cold Impact Test (for diameter > 12.5 mm) E) Insulation resistance test F) High voltage test (water immersion test ) G) High voltage test at room temperature H) Flammability Test

:

As per IS 1554(Pt.I) :

As per IS 1554(Pt.I)

: As per IS 1554(Pt.I)

7.2 Special Tests These tests will be conducted on any two drums of each group as per Purchaser’s choice. 1. Water absorption test for insulation as per IS 5831 2. Oxygen Index test as per ASTMD-2863. Minimum guaranteed value shall be 29. 3. Temperature Index test to ASTMD-2863. Minimum guarantee value shall be 250.0. 4. Acid gas generation test as per IEC 60754. Maximum guaranteed value should be 20

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

76

5. Smoke density test as per UTTD test method F4 of ASTM-D2843.

7.3 Acceptance Tests 1. Tensile test (for aluminium) 2. Annealing test (for copper) 3. Wrapping test (for Aluminium) 4. Conductor resistance test 5. Test for thickness of insulation and sheath 6. Insulation resistance test 7. High voltage test at room temperature 8. Dimensional check.

7.4

Routine Tests

These tests will be conducted on each drum of FRLS cable. 1. Conductor resistance test 2. High voltage test at room temperature Existence of facilities for carrying out all the routine tests in manufacturer’s works shall be specifically confirmed. Dates of installation and commissioning and details of make, year of manufacture etc. for machines/test apparatus for carrying out ’special tests’ shall be furnished. The purchaser at his discretion may call for additional tests not included here, as may be required to ensure that all materials are satisfactory and in accordance with the specifications. All tests shall be carried out be the manufacturer expeditiously free of cost. Report for Type tests including special tests shall be furnished with the Routine test certificates for the first lot of each type/group of cable in the event of order. Reports for Acceptance tests shall similarly be furnished along with the Routine Test Certificates for all individual lots beginning with the first batch. Routine test certificates for all drums shall be furnished. Special tests shall be carried out on any two drum length of Power and control Cables at Purchaser’s choice. All test certificates shall be submitted to the Purchaser for approval before despatch. Approval of test certificates by the Purchaser must precede despatch of the cables. The Purchaser reserves the right to witness all tests, for which at least 3 weeks advance intimation for inspection, will be required. Under armour and overall diameters of cables (average values) shall be recorded on each Routine test certificates.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

77

8

Documentation

As part of the offer, the tender shall furnish relevant descriptive and illustrative literatures on cable and also the drawings and technical data for the following besides other : 1. Descriptive literature/manufacturer’s leaflets giving construction details cross-section dimensions and characteristics of different type of cables offered. 2. Current rating of cable including derating factors due to grouping, ambient temperature and type of various installations. 3. Table for short circuit withstand capacity of cable and armour material indicating time duration. 4. Write-up, sketches, other details illustrating manufacturer’s recommendation for splicing jointing and termination. 5. Table of voltage drop per ampere meter duty considering impedance at 50 Hz at maximum conductor operating temperature. 6. Tables giving mechanical constructional details including weight, diameter etc.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

78

9

Specific Requirements CABLES Sl.

1 1 2 3 4 5 7 8 1 2 3 5 6 7

Description

Type

2

3

Aluminium Cable 1.1KV grade, FRLS, LT cable 1.1KV grade, FRLS, LT cable 1.1KV grade, FRLS, LT cable 1.1KV grade, FRLS, LT cable 1.1KV grade, FRLS, LT cable 1.1KV grade, FRLS, LT cable 1.1KV grade, FRLS, LT cable Copper Cable 1.1KV grade, FRLS cable 1.1KV grade, FRLS cable 1.1KV grade, FRLS cable 1.1KV grade, FRLS cable 1.1KV grade, FRLS cable 1.1KV grade, FRLS cable

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

3.5C x 300 sq.mm 3.5C x 95 sq.mm 3.5C x 50 sq.mm 3.5C x 25 sq.mm 4C x 16 sq.mm 2C x 16 sq.mm 2C x 10 sq.mm 4C x 2.5 sq.mm 7C x 2.5 sq.mm 12C x 2.5 sq.mm 19C x 2.5 sq.mm 4C x 6 sq.mm 4C x 10 sq.mm

79

SPECIFICATION FOR ALUMINIUM TUBES DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1

Scope

This specification covers the basic technical requirements of seamless extruded Aluminium tubes of different lengths and sizes. These Aluminium tubes will be used as busbars in 220 KV, 132 KV, 33 KV, 3-Phase AC, outdoor switchyards.

2

Standards

The Aluminium tubes covered by this specification shall conform to the latest edition of IS : 5082. In the event of the Bidder offering the equipment conforming to specifications other than the above mentioned standards, an English translation of the specification shall be submitted with the tender stating the relevant advantages. The Aluminium tubes shall have ISI standard mark. Grade of Aluminium material is 63401 - WP. In the event of a conflict between the above standards and the stipulations laid down in this specification, the decision of the purchaser shall be final and binding.

3

Operating Conditions • Nominal System Voltage (KV rms)

-

220 / 132 / 33 KV.

• Highest system voltage (KV rms)

-

245 / 145 / 36 KV.

• No. of Phases

-

3.

• Operating frequency (Hz)

-

50.

• System neutral connection

-

a) 220 KV and 132 KV - solidly earthed b) 33 KV - earthed through a grounding transformer

• Clearance between phases

-

a) 220 KV System - 4000 mm b) 132 KV System - 2743 mm c)

4

33 KV System - 1220 mm

Guarantee

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

80 The performance and test figures given with the tender shall be guaranteed and the tolerance applicable shall be stated. The items not conforming to the guaranteed figures shall be liable to rejection by the Purchaser. Any item found not satisfying the above performance characteristics or not conforming to the specification shall be replaced at site, free of the cost within a reasonable time but not later than three months from the date of reporting the defect to the supplier. The Purchaser reserves the right to call for samples if considered necessary and the same shall be submitted by the Bidder free of cost without any obligation.

5

Completeness of Offer

The materials offered, shall be complete with all components and accessories which are necessary or usual for their efficient performance and satisfactory maintenance. Such parts shall be deemed to be within the scope of the contract whether specifically included or not, in this specification and tender schedule. The contractor shall not be eligible for any extras in respect of such accessories etc.

6

Tests

The Bidder shall also submit full particulars of testing facility available at the manufacturing plant or the manufacturing quality plan. The following tests shall be carried out in presence of the Purchaser’s representative on the required number of samples of Aluminium tubes as stipulated in this or any other approved standard : 1. Chemical composition of Aluminium. 2. Ultimate shearing strength. 3. Ultimate tensile strength. 4. Electrical resistivity or conductivity.

7

Packing

The Aluminium tubes shall be packed in such a manner that they do not suffer cut marks or bend during transit.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

81

8

Specific Requirements

Aluminium tubes shall have the following parameters: AL. TUBES Sl.

Parameter

3inch

212inch

1

2

3

4

1 2

Outside dia (mm) Wall thickness (mm)

88.90 5.49

73.03 5.17

3

Unit length (meter)

As per unit length specified in price schedule

As per unit length specified in price schedule

4 5

Weight/Meter in (kg) Min. ultimate tensile strength (kg/sq mm)

4.00±2% 20.5

3.00±2% 20.5

6

0.2% Proof stress Yield strength (kg/sq mm)

16.6

17.34

7 8

Modulus of Elasticity (kg/mm) Minimum Elongation on 50.8 mm (%) Max. DC resistance/meter run at 20 degC (microohm) Temperature coefficient of resistance/ degC Minimum electrical conductivity at 20 degC (% IACS) Current carrying capacity outdoors at 50 Hz continuous (Amps)

6700 10

6700 10

60.7

26.08

0.00364

0.00364

55

55

2350

1950

13

Temp. rise over an ambient of 50 degC (degC)

35

35

14

Electrical resistivity (Max) at 20 degC (microohm cm)

3.133

3.133

15

Chemical Composition (in %)

Cu - 0.05 max, Cu - 0.05 max, Mg Mg - 0.4 - 0.9, Si - 0.4 - 0.9, Si - 0.3 - 0.3 - 0.7, Fe 0.7, Fe - 0.5 max, 0.5 max, Al Al -%Remainder Remainder

16

Thermal conductivity (Cal./Sec./Sq.cm/cm/degC) at 0.52 100 degC

17

Tolerance on wall thickness and diameter

9 10 11 12

shall conform to IS 2673 (latest version)

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

0.52 shall conform to IS 2673 (latest version)

82

AL. TUBES Sl.

Parameter

112inch

1

2

3

1 2

Outside dia (mm) Wall thickness (mm)

48.26 3.68

3

Unit length (meter)

As per unit length specified in price schedule

4 5

Weight/Meter in (kg) Min. ultimate tensile strength (kg/sq mm)

1.40±2% 20.5

6

0.2% Proof stress Yield strength (kg/sq mm)

16.5

7 8

Modulus of Elasticity (kg/mm) Minimum Elongation on 50.8 mm (%) Max. DC resistance/meter run at 20 degC (microohm) Temperature coefficient of resistance/ degC Minimum electrical conductivity at 20 degC (% IACS) Current carrying capacity outdoors at 50 cps continuous (Amps)

6700 10

0.00364

13

Temp. rise over an ambient of 50 degC (degC)

35

14

Electrical resistivity (Max) at 20 degC (micro-ohm 3.133 cm)

9 10 11 12

55.68

55 1160

15

Chemical Composition (in %)

Cu - 0.05 max, Mg - 0.4 - 0.9, Si - 0.3 0.7, Fe - 0.5 max, Al -%Remainder

16

Thermal conductivity (Cal./Sec./Sq.cm/cm/degC) at 100 degC

0.52

17

Tolerance on wall thickness and diameter

shall conform to IS 2673 (latest version)

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

83

SPECIFICATION FOR CONDUCTOR DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA – 700054

1

Scope

This specification covers the design, manufacture, testing, supply and delivery at destination/site of the following conductors at 220/33 kV Burnpur sub-station: • ACSR MOOSE conductor (size - Al-54/3.53 mm, St-7/3.53 mm) Hereafter ACSR shall mean “ Aluminium Conductor Steel Reinforced “.

2

Standards

ACSR conductor shall conform to the latest edition of IS - 398 (PART-2), (PART-3) & (PART-5) . The conductor shall have ISI standard mark. If the materials conform to a standard other than the Indian Standard specification then an English version of the standard in addition to the original standard if written in a language other than English, should be submitted indicating clearly the advantage, if any, that would be obtained by the purchaser by adopting this standard instead of the said Indian Standard. The standard proposed to be adopted shall clearly be stated in the tender papers. Any deviations from this specification will be considered provided they are necessary either to improve the utility, performance, efficiency and / or durability of the equipment or to secure an overall economy consistent with the purchaser’s requirements hereinafter specified.

3

Manufacturing Requirements

The ACSR conductors shall consist of hard drawn aluminium strands and galvanised steel strands. The aluminium strands of the ACSR conductor shall be drawn from electrolytic aluminium rod having purity of not less than 99.5%. The steel strands of the ACSR conductor shall be drawn from steel produced by either acid or basic open-hearth process or by the electric furnace or basic oxygen process. No steel produced by the Bessemer process shall be used for drawing wires. All strands of ACSR conductors shall be reasonably uniform and shall be free from all defects, die marks and scratches after drawing and also after stranding. The length of any piece of finished conductor shall not vary from the standard length guaranteed in the Schedule of Technical Particulars. Galvanising shall be uniform, free from blisters and shall not peel off due to abrasion. Zinc coating

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

84 shall be thick and uniform enough to withstand the requirements stated in the indicated standards.The zinc used for galvanizing shall be electrolytic high grade zinc not less than 99.95% purity.

4

Tests

All the tests shall be carried out on the required number of samples as stipulated in the IS-398 IS398 (Part - II) or any other approved standard, in presence of purchaser’s representative. Selection of samples, conditions of repetitive tests and rejection of materials if any shall strictly be in accordance with the requirements of the approved standard or as per the standard practice of the manufacturers and in the later case full details of the standard practice shall be stated in the tender. The relevant test reports for the repetitive tests including the results of the tests in which the equipment failed to satisfy the requirements of the approved standard, shall also be submitted in triplicate. All costs for tests / retests shall be borne by the manufacturer. The manufacturer shall submit full particulars of the testing facilities available at its laboratory and shall confirm that the laboratory will be readily available, when required, for testing of all the equipment offered by it. The Purchaser may choose to conduct any or all of the tests stipulated in the indicated standard be carried out in a Govt. laboratory. The manufacturer shall arrange to carry out such tests expeditiously and at its own cost. Test reports in triplicate for such tests shall be submitted to the Purchaser for approval.

5

Packing

All cable reels shall conform to relevant IS and be of dimensions approved by the purchaser and made of seasoned wood sufficiently strong to ensure arrival at site intact, withstanding normal handling and hazards inland and ocean transit. The reels shall be of such size as to provide at least 0.5” (half inch) clearance at all points from the cable to the inner surface of the lagging. All reels shall have two coats of aluminium paint on both inside and outside surface and shall be fitted with malleable iron hub-bushings each having a 2.75” (inch.) diameter hole. All reels shall have a layer of waterproof paper around the hub under the cable and another layer over the outermost layer of the cable, that is, next to the lagging. The reels shall be properly reinforced with galvanised steel wires or iron strips over the lagging in two places in an approved manner. The wooden drums shall preferably be given protective coating of a reliable organic wood preservative before painting with Aluminium paint and the lagging shall also be given a similar treatment before being fixed on the drum. There shall be one specified length of conductor in each drum.

6

Marking of Drums

Each drum shall be marked on the sides as follows : 1. Name or designation of the consignee to be furnished by the Purchaser.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

85 2. Ultimate destination and / or the port of discharge as required by the Purchaser. 3. The items and the respective quantities contained in it e.g size and type of conductor,length of conductor in meter etc. 4. The net and gross weights of the materials. The markings shall be stencilled in indelible ink on each drum.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

86

7

Specific Requirements

ACSR conductors shall satisfy the following parameters: CONDUCTORS Sl.

Parameter

ACSR MOOSE

1

2

3

1

Physical constants for hard drawn Aluminium wires shall be as follows:

a

Maximum Resistivity of Al wire

0.028264 Ohmmm2/m

b

Density of Al. wire(at 20°C)

2.703 g/cm3

c

Coefficient of linear expansion

23.0 X 10-6/°C

d

Wires

EC grade Aluminium of purity ≥ 99.5%

2

Physical constants for galvanised steel wire shall be as follows:

a

Density(at 20°C)

7.80 gm/cm3

b

Coefficient of linear expansion

11.5 X 10-6/°C

3 a b 4 5 6 7

Stranding and wire diameter Aluminium Steel Nominal Sectional area of conductor Approximate total mass Calculated equivalent Al area Overall diameter of the conductor Calculated resistance at 20oC (corrected to standard weight) Ultimate tensile strength of conductor

54/3.53 mm 7/3.53 mm 597.0 mm2 2004 Kg/KM 528.5 mm2 31.77 mm 0.0555 Ohm/KM 161.20 kN

8 9 10

11

Outside Aluminium layer (24 wire layer) Intermediate Aluminium layer (18 wire layer) Intermost Aluminium layer (12 wire layer) Final modulus of elasticity

Max : 28 Min : 13 Max : 14 Min : 10 Max : 16 Min : 10 Max : 17 Min : 10 69 GN/m2

12

Final Coefficient of linear expansion

19.3 X 10-6/°C

13

Normal length without joint, weld

1200 Mtrs. Or higher

a b c d

Steel core

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

87

Sl.

Parameter

1

2

14 a b c d e f 15 a b 16 a b 17 a b

Diameter of each strand : Standard - Steel Standard - Aluminium Maximum - Steel Maximum - Aluminium Minimum - Steel Minimum - Aluminium Sectional area of each strand: Steel Aluminium Weight of each strand Steel Aluminium Minimum ultimate tensile stress Steel Aluminium

18 A

Minimum breaking load of each wire before stranding

18 B

Minimum breaking load of each wire after stranding

19 a b

Zinc coating No. and duration of Dips Minimum weight of Zinc coating

ACSR MOOSE 3 3.53 mm 3.53 mm 3.60 mm 3.57 mm 3.46 mm 3.49 mm 9.787 mm2 9.787 mm2 76.34 Kg/Km 26.45 Kg./Km 134 Kg/mm 16.59 Kg/mm Steel : 12.86 kN Aluminium : 1.57 kN Steel : 12.22 kN Aluminium : 1.49 kN 1 min. 3 dips 250 gm/m

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

88

SPECIFICATION FOR CONNECTOR DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1 Scope This Specification covers design, manufacture, assembly and testing at manufacturer’s works before dispatch, followed by supply and delivery of Clamps and Connectors for 220KV/ 132KV/ 33KV substations.

2

Standards

The Clamps and Connectors under this specification shall conform strictly to the latest version of the following standards as amended except where specified otherwise: 1. IS-5561

: Electrical Power Connectors.

2. IS-10162 : Spacers and spacer dampers for twin horizontal bundle conductors. 3. IS-617

: Aluminium and Aluminium Alloy ingots and castings for general engineering purposes .

4. IS-5082

: Wrought aluminium and aluminium alloy bars, rods, tubes and sections for electrical purposes

5. IS-1285

: Wrought Aluminium and Aluminium Alloys - Extruded Round Tube and Hollow Sections for General Engineering Purposes – Specification

6. IS-2629

: Recommended practice for Hot Dip Galvanising of Iron and Steel.

7. IS-2633

: Method of testing uniformity of coating on Zinc coated articles.

The materials conforming to any other standards will also be acceptable if 1. the salient points of these standards and points of differences between these and the above standards can be clearly brought out. and 2. it can be proved to the satisfaction of the Purchaser that adoption of the proposed standard would ensure equal or better performance.

3

Functional Requirements

The functional requirements may be enumerated as follows:

3.1

Electrical rating

Short time rating for 220KV and 132KV shall be 40 kA for 1 second and 25 kA for 3 seconds for 33 KV. The rated current of the connectors shall be governed by the item description of connectors

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

89

indicated herein. However, rating and type of the clamps and connectors shall be finalized after detail engineering.

3.2

Temperature Rise

The limits of temperature rise shall be as indicated in Clause 6 in IS: 5561.

4

Construction

The connectors shall be extruded type of best quality and workmanship and in line with all the requirements laid out in the adopted standards. The thickness and contact surface should be maintained in such a way that the connector conforms to IS: 5561. All bolts, nuts and washers should have a bright finish. The holes of plain washers shall be reasonably concentric with the outer periphery. All sharp edges should be rounded off. Spring washers shall be supplied in natural finish and conforming to relevant IS specification and shall be Electro galvanised. Suitable size Aluminium braids are to be provided at each bolt points between upper and lower half of the connector to by-pass the bolt. Whenever copper to aluminium joints are required, 2 mm thick cold rolled aluminium copper bi-metallic strips shall be used between aluminium connector and copper terminal of the equipment as a sandwich plate between flat surfaces or as a sleeve around the circular studs to prevent galvanic corrosion. The current carrying parts shall be so designed, manufactured that contact resistance is reduced to the minimum. The resistance shall be as specified in IS: 5561. All connectors should be so designed and manufactured so as to offer ease of installation as these are to be used in overhead installations. Design should be such that full tightening of nuts and bolts is possible with the ordinary tools. The connectors shall be designed so as to avoid local corona, sound and visible discharge. Corresponding parts for each type of connector should be made to gauge or jig and should be interchangeable in every respect. The connectors should be legibly and indelibly marked with trademark of the manufacturer.

4.1

Materials

1. For connecting equipment terminal and conductors: Extruded Aluminium Alloy grade 63400 of IS 1285 2. For connecting equipment terminal of copper or brass : Extruded Al. alloy grade 63400 of IS 1285 with 2 mm thick bimetallic liner 3. Strain and PG clamps for GI shield wire : Dip forged steel 4. Earth clamps, earth strip supporting clamps, cleat clamps on wall and structures : MS hot dip galvanised 5. For bolts, nuts and plain washers of all clamps and connectors and spacers : Hot dip galvanised mild steel for size M12 and above. Electro galvanised mild steel for size below M12 6. Springs : Electro galvanized

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

90

5

Tests

There must be adequate testing facilities at the Works to conduct all acceptance and routine tests referred to in the above standards. A sample of each type of clamp and connector selected at random by the Purchaser shall be tested for Aluminium purity from any Govt. recognised Test House and the report submitted to the Purchaser prior to despatch of materials. The following acceptance and routine tests shall be carried out on the connectors as per IS: 5561 and IS: 2633

5.1

Acceptance Tests

1. Verification of dimensions. 2. Tensile Test. 3. Resistance Test. 4. Galvanising Test (when applicable).

5.2

Routine Test

1. Visual inspection. 2. Verification of dimensions.

5.3

Type Tests

The following tests shall be constitute type tests for clamps and connectors: 1. Tensile test. 2. Resistance test. 3. Temperature rise test. 4. Short time current test. The following tests shall be constitute type tests for spacers: 1. Resilience test. 2. Vibration test. 3. Short circuit current test. 4. Magnetic power loss test.

6

Documentation

The following shall constitute the documentation for the specified items: 1. Dimensional drawings of each item with mention of tentative weight and material of each item 2. Tests reports.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

91

7 Specific Requirements CONNECTORS Sl.

Type Description

1

2

220KV BAY (2 BUS SYSTEM) 1 Pipe bus support connector for 2-1/2” IPS Al. tube suitable for 127 mm PCD 220 kV solid core post insulator (a) Rigid Type

Continuous Current Rating 3 1250A

(b) Expansion Type (c) End (free) type 2

220 kV CT Connectors suitable for

1250A

(a) Rigid type suitable for 2-1/2” IPS Al. tube (b) Clamp type suitable for ACSR Moose/Zebra Conductor 3

220 kV Normal Isolator

1250A

(a) Rigid type suitable for 2-1/2” IPS Al. tube (b) Expansion type suitable for 2-1/2” IPS Al. tube 4

Expansion type connector for 220 kV SF6 breaker and 2-1/2” IPS 1250A Al. tube 1250A Tee Connector

5

(a) 2-1/2” IPS Al. tube to ACSR Single Moose (b) 2-1/2” IPS Al. tube to ACSR Double Moose 6

Guide pipe support clamp for 220 kV side 127mm PCD solid core 1250A post Insulator (a) Suitable for 2-1/2” IPS Al. tube for TB side (b) Suitable for 3” IPS Al. tube for MB side

7

9

PG clamp suitable for ACSR Moose / AAAC Zebra Conductor ( Extruded Al.) Spacer suitable for double ACSR Moose Conductor (spacing 330 mm center to center) U-Bolt 22diaX150mm for Gantry

10

U-Bolt 25diaX275mm for A Frame

8

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

92

SPECIFICATION FOR HARDWARE AND ACCESSORIES DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA – 700054

1 Scope This specification covers design, manufacture, testing at manufacturer’s works before despatch, supply and delivery of Hardware and accessories for 220KV, 132KV, 33KV substations.

2

Standards

The materials covered under this specification shall comply with the requirements of the latest edition of the following standards. 1. IS 2486, (all relevant parts) : Metal fittings for Insulator for overhead power lines with nominal voltage greater than 1,000V. 2. IS 2629

: Recommended practice for hot dip galvanising of iron and steel.

3. IS 2633 : Method of testing uniformity of coating of zinc coated articles. 4. IS 6745 : Method for determination of mass of zinc coating on zinc coated iron and steel articles 5. IS 5561

:

Specification for Electric power connectors.

The materials conforming to any other national standards which ensure equal or better performance shall also be acceptable. The salient point of these specification and points of difference between these and the above specification shall clearly brought out in the bid and English version of the standard shall be submitted.

3

Construction

The material offered shall be of best quality, workmanship, well finished and of approved design. All casting shall be free from blow-holes, flaws, cracks or other defects and shall be smooth, close grained and of true forms and dimension. All mechanical surface shall be true, smooth and finished. Metal fittings of specified materials for string hardware are required to have excellent mechanical properties such as strength, toughness and high corrosion resistance and free from corona formation. All current carrying parts shall be so designed and manufactured that contact resistance is reduced to the minimum.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

93 Compression areas shall be clearly marked on each accessories designed for continuous die compression shall bear the word ‘COMPRESS FIRST’ near the point of each Accessory where the compression begin. Accessories designed for intermittent die compression shall bear the identification marks ‘COMPRESSION ZONE’ and ‘NON COMPRESSION ZONE’ distinctly of compression. The letters, numerals and other marking on finished accessories shall be distinct and legible. All bolts, nuts, bolt-heads shall be white worth standard thread. Bolts heads and nuts shall be locked in an approved manner. The threads in nuts and tapped holes shall be cut after galvanising shall be well lubricated or greased. All other threads shall undercut to take care of increase in diameter due to galvanising. Bolts and nuts should be of approved make. 2.5% extra bolts, nuts, washers shall be supplied. The general design of Hardware and Accessories shall be such as to ensure uniformity, high strength, free from corona formation and high resistance against corrosion even in high level of atmosphere, pollution. All hooks, eyes pins, bolts, suspension clamps and other fittings for attaching insulator to the tower or to the line conductor, shall be so designed as to reduce damage to the conductor, insulator or the fitting arising from the conductor vibration. Special attention must be paid to ensure smooth finished surface throughout. Adequate bearing area between fittings shall be provided and ‘point’ or ‘line’ contacts shall be avoided. All fittings shall be free from cracks, shrinks, slender, air holes, burrs or rough edges. All current carrying parts shall be designed to have minimum contact resistance. The design of the fittings shall be such as to avoid local corona formation or discharges that likely to cause interference to tele-transmission of signals of any kind. The tenderer shall offer tinned copper bonding pieces for connecting the ground wire suspension and tension clamp with tower body suitable for earthing. Each bond pieces shall have suitable compression type connecting leg or thimble on either side for making connections to clamps and tower body. The connecting socket should be made of tinned copper.

3.1

Galvanisation

All ferrous parts of hardware shall be galvanization in accordance with the latest edition of IS-2629 or any other equivalent authoritative standards. The weight of zinc coating shall be determined as uniformity of coating of hot dip galvanized articles or any other equivalent authoritative standard. The zinc used for galvanization shall conform to grade Zn 99.95% of IS-209. The galvanized parts shall withstand six(6) dip for 1 minute each time while testing uniform of Zinc coating as per IS-2633. Spring washers shall be electro galvanized.

4

Hardware Requirement

Materials for the various components of the Hardware shall be as follows:

4.1

Single tension set for conductor

1. Anchor Shackle 2. Ball eye, ball link (H.H) 3. Tower side arcing horn (for line hardware only)

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

94

4. Socket clevis, socket eye with R type security clips 5. Line side arcing horn (for line hardware only) 6. Compression type dead end clamp with jumper for 132KV and 220KV or bolted type dead end clamp for 33KV 7. Bolts, nuts, washers, spring washer and split pin for the above

4.2

Double tension set for conductor

1. Anchor Shackle 2. Chain link 3. Yoke plate 4. Tower side arcing horn 5. Ball clevis 6. Socket clevis with R type security clips 7. Line side arcing horn (for line hardware only) 8. Compression type dead end clamp with jumper for 132 KV and 220 KV or bolted type dead end clamp for 33KV 9. Bolts, nuts, washers, spring washer and split pin for the above

4.3

Single tension set for twin conductor

For 220 KV and 132 KV substations only. 1. Anchor Shackle 2. Ball eye, ball link (H.H) 3. Socket clevis, socket eye with R type security clips 4. Yoke plate 5. Turn buckle 6. Compression type dead end clamp with jumper for 132 KV and 220 KV or bolted type dead end clamp for 33KV 7. Bolts, nuts, washers, spring washer and split pin for the above

4.4

Single suspension set for conductor

1. Ball hook 2. Tower side arcing horn 3. Socket clevis, socket eye with R type security clips 4. Line side arcing horn (for line hardware only) 5. Anchor shackle 6. Armour grip suspension clamp with armour rods (for 33KV without armour rod)

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

95

7. Compression type dead end clamp with jumper for 132KV and 220KV or bolted type dead end clamp for 33KV 8. Bolts, nuts, washers, spring washer and split pin for the above

4.5

Double suspension set for conductor

1. Ball hook 2. Yoke plate 3. Tower side arcing horn (for line hardware only) 4. Socket clevis, socket eye with R type security clips 5. Ball clevis 6. Line side arcing horn (for line hardware only) 7. Anchor shackle 8. Armour grip suspension clamp with armour rods (for 33KV without armour rod)

4.6

Suspension set for earthwire

1. Eye hook 2. Suspension clamp 3. Flexible copper bond 4. Bolts, nuts, washers, spring washer and split pin for the above

4.7

Tension set for earthwire

1. Anchor Shackle 2. Compression type dead end clamp with jumper sleeve with Aluminium casing 3. Bolts, nuts, washers, spring washer and split pin for the above

4.8

String set details

1. 33KV single suspension set Number of discs per string

:

3

Electro-mechanical strength

:

70 kN

Ball diameter

:

16 mm

Spacing between discs

:

145 mm

Number of discs per string

:

2x3

Electro-mechanical strength

:

70 kN

Ball diameter

:

16 mm

Spacing between discs

:

145 mm

2. 33KV double suspension set

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

96 3. 33KV single tension set Number of discs per string

:

4

Electro-mechanical strength

:

70 kN

Ball diameter

:

16 mm

Spacing between discs

:

145 mm

4. 33KV double tension set Number of discs per string

:

2x4

Electro-mechanical strength

:

70kN

Ball diameter

:

16mm

Spacing between discs

:

145mm

Number of discs per string

:

9

Electro-mechanical strength

:

70kN

Ball diameter

:

16mm

Spacing between discs

:

145mm

Number of discs per string

:

2x9

Electro-mechanical strength

:

70kN

Ball diameter

:

16mm

Spacing between discs

:

145mm

Number of discs per string

:

10

Electro-mechanical strength

:

120kN

Ball diameter

:

20mm

Spacing between discs

:

145mm

Number of discs per string

:

2 x 10

Electro-mechanical strength

:

120kN

Ball diameter

:

20mm

Spacing between discs

:

145mm

Number of discs per string

:

14

Electro-mechanical strength

:

70kN

5. 132KV single suspension set

6. 132KV double suspension set

7. 132KV single tension set

8. 132KV double tension set

9. 220KV single suspension set

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

97 Ball diameter

:

16mm

Spacing between discs

:

145mm

Number of discs per string

:

2 x 14

Electro-mechanical strength

:

70kN

10. 220KV double suspension set

Ball diameter

:

16mm

Spacing between discs

:

145mm

Number of discs per string

:

15

Electro-mechanical strength

:

160kN

Ball diameter

:

20mm

:

170mm

Number of discs per string

:

2 x 15

Electro-mechanical strength

:

160kN

Ball diameter

:

20mm

Spacing between discs

:

170mm

11. 220KV single tension set

Spacing between discs 12. 220KV double tension set

4.9

Mechanical Strength

The ultimate mechanical strength of the hardware should in no case be lower than the following: 1. 33KV suspension set for AAAC Panther

:

45 kN

2. 33KV tension set for AAAC Panther

:

45 kN

3. 132KV suspension set for AAAC Panther

:

70 kN

4. 132KV tension set for AAAC Panther

:

120 kN

5. 132KV tension set for twin Panther / single Moose

:

120 kN

6. 220KV suspension set for ACSR Zebra

:

70 kN

7. 220KV tension set for ACSR Zebra

:

160 kN

8. 220KV tension set for single Moose / double Moose

:

160 kN

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

98

4.10

Material

1. Anchor Shackle

: Forged steel

2. Chain Link

: Forged steel

3. Ball hook or ball hook (HH) : Forged steel 4. Socket eye (HH)

: Forged steel

5. Ball clevis

: Forged steel

6. Socket clevis

: Forged steel

7. Yoke plate

: Mild steel

8. Arching horn

: Mild steel

9. Suspension clamp

: Aluminium alloy

10. Dead end/cross-arm strap

: MS Flat

11. Tension clamp (compression)

: Aluminium alloy (steel for ACSR)

12. Tension clamp (bolted type)

: Aluminium alloy

13. Tension clamps and sleeves for earthwire : HDG steel with Aluminium encasing

5

Dimensions

The minimum length of the different hardware string sets shall be as detailed below : 1. Single Suspension set for ACSR Panther

: 2350 mm for 220 KV 1600 mm for 132 KV 690 mm for 33 KV

2. Single tension set for ACSR Moose

: 2900 mm for 220 KV 1800 mm for 132 KV 935 mm for 33 KV

3. Single tension set for ACSR Zebra

: 2900 mm for 220 KV 1800 mm for 132 KV.

4. Single tension set for ACSR twin Moose with turn-buckle - length variation from : 3300mm to 3600mm for 220 KV, 2000mm to 2500mm for 132 KV. 5. PG clamp for ACSR Moose conductor(4 bolted Type): (220 x 110 x 60)mm for 220 KV 6. PG clamp for ACSR zebra conductor (3 bolted Type): (180 X 95 X 54)mm for 132 KV 7. PG clamp for AAAC Panther conductor (3 bolted type): (1500 X 85 X 15)mm for 33 KV

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

99

6

Suspension assembly

6.1 Tension clamps Compression type tension clamps shall be made of high strength extruded Aluminium alloy and suitable for ACSR Moose / Zebra / Panther conductor in 220 KV and 132 KV system. Bolted type hardware (4 bolts type) shall be used in 33KV system suitable for AAAC Panther Conductor. The clamps shall also be designed, manufactured and finished to have a suitable shape without sharp angles at the end and to hold the respective conductor properly. It should however have sufficient contact surface to minimise damage due to fault current. The clamp shall have slipping strength of not less than 95% UTS of respective conductors. Compression type tension clamps shall be made of high strength aluminium alloy and suitable for respective conductor. The tension clamps shall not permit slipping of or damage to or failure of the complete conductor at any part thereof at a load less than 95% of the ultimate strength of the conductor. The electrical conductivity of tension clamps shall have the same value as the conductor and shall be of such design as will ensure unrestricted flow of current without use of parallel groove clamps.

6.2

Suspension Clamps for conductor

Suspension clamps for 220KV line and 132KV system shall be suitable for supporting the respective conductor wrapped with armour rods. Suspension clamp for 33KV shall be without armour rods. The clamp body and keeper shall be high strength aluminium alloy. The suspension clamp shall consist of neoprene insert for armour grip. The suspension clamp shall be provided with galvanised steel U bolt, nut, washer etc. The suspension clamp shall be so designed manufactured and finished to have a suitable shape without sharp angles at the end and to hold the respective conductor properly. It should however have sufficient contact surface to minimise damage due to fault current. The clamp for 33KV shall be of envelope type (SALVI design) and shall have ease of oscillation around the horizontal axes passing through the center line of Conductor. The suspension clamp shall permit the conductor to slip before failure of the conductor occurs and shall have sufficient slipping strength to resist the conductor tension under broken wire condition. The conductor should not slip at a load of 8% of the breaking load of the conductor. The slip strength shall not exceed 15% of breaking load of the conductor. For 33 KV suspension string the clamp shall be of envelope type suitable for AAAC Panther/ twin Panther with 3 Nos. Disc Insulators.

6.3

Suspension clamp for ground wire

Suspension clamps of suitable size are required for holding the galvanised stranded steel wire at suspension points. The suspension set shall be suspended from tower hanger. The clamp shall be so designed that the effect of vibration both on ground wire and the fitting is minimum. The clamp shall permit the ground wire to slip before the failure of ground wire occurs. One leg of the U-bolt holding the keeper piece of clamps shall be kept sufficiently long and shall be provided with threaded nuts and locking nut for fixing the flexible earthing bond between the suspension clamp and the tower structure.

7 7.1

Dead end assembly Dead end assembly for conductor

Compression type dead-end assemblies for galvanised stranded steel wire shall be required for use on

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

100

tension towers. The dead end assemblies shall be supplied complete with jumper terminals, nuts, bolts, suitable bind pieces between the steel clevis and tower strain plates so as to provide sufficient flexibility to the attachment. Dead end assembly shall have conductivity not less than GSS ground wire and tensile strength not less than 90% that of the UTS of the ground wire. The tension clamp should be made of forged steel with Aluminium encasement over it. One of the bolt holding jumper terminal of dead end assemblies shall be kept sufficiently long and threaded and shall be provided with washers, nuts and locking nuts for fixing the flexible earthing bond between the dead end assembly and tower structure. The earthing bond shall be made of tinned copper having at least 500mm length and should be compressed with two sockets made of tinned copper at both ends. All ferrous parts shall be hot dip galvanised.

7.2

Dead end assembly for earthwire

All tension towers shall be fitted with suitable compression type tension clamps to support 7/3.15mm earthwire. Anchor shackle shall be supplied which shall be suitable for attaching the tension clamp to strain plates. The clamps shall have adequate area of bearing surface to ensure positive electrical and mechanical contact and shall not permit any slip to the earthwire under working tension and vibration conditions. The angle of jumper terminal to be mounted should be 30 deg from the vertical. The complete assembly shall be so designed as to avoid undue bending in any part of the clamp and shall not produce any hindrance to the movements of the clamps in the horizontal or vertical directions. The slip strength of the assembly shall not be less than 95% of the ultimate strength of the earthwire. The clamps shall be complete with all the components including anchor shackle, bolts, nuts, washers, split pin, jumper arrangement etc.

8 8.1

Requirement of accessories Mid-span straight joint

Material: Aluminium alloy for AAAC conductor, Mild steel for steel wire in ACSR conductor, HDG steel with Aluminium encasing for earthwire. Minimum failing load: 95% of UTS of conductor or earthwire. Electrical resistance at 20oC: 75% of measured resistance of the equivalent length of conductor or earthwire. The mid span joints for conductor and earthwire shall be of compression type. The mid span joints for ACSR shall comprise of outer Aluminium sleeve made of Aluminium (99.5% purity), inner sleeve of HDG steel and two filler plugs. The mid span joints for AAAC shall comprise of Aluminium sleeve made of Aluminium alloy. The ground wire mid span joints shall be of HDG steel with aluminium encasement over it. The sleeves shall be of circular shape suitable for compression into hexagonal shape. The inner and outer diameters and lengths of these joints before and after compression shall be clearly shown on the drawing.

8.2

Repair sleeve

Material: Aluminium alloy for conductor and HDG steel with Aluminium casing for earthwire. Minimum failing load: 95% of UTS of conductor or earthwire. The repair sleeve of conductor shall be in two halves (one body and one keeper) and this should be extruded Aluminium (99.5%) purity. The repair sleeve of ground wire shall be of HDG steel with Aluminium encasing. The repair sleeve shall be of curcular shape suitable for compression into hexagonal shape.

8.3

Vibration damper

Clamp shall be made from gravity die cast Aluminium alloy, messenger cable from high strength galvanised stranded steel wire and weight from galvanised cast iron. The 4R (4 frequency) type vibration dampers shall effectively damp out the vibrations of the conductors and galvanised stranded steel wire. The tenderers shall give full details of damping

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

101

characteristics and energy dissipation curves of the dampers and guarantee their effectiveness. The number of vibration dampers required to damp out the conductor vibration effectively and their points of fixation shall be indicated. The clamp of vibration dampers shall be made of Aluminium alloy. The clamp shall have sufficient grip to maintain the damper in position on the conductor without damaging the strands, premature fatigue of the clamp body and clamp cap shall be smooth, free of projection, grit or other material which could cause damage to the conductor when the clamp is installed. The messenger cable shall be made of high strength steel galvanised strands and preformed in order to prevent subsequent drop in weights in service. Clamping bolts shall be provided with self locking nuts designed to prevent corrosion of the threads or loosening durin service, ensuring that no slippage occurs. All ferrous parts shall be hot dip galvanised. The spring washers should be electro galvanised. The ends of the messenger cable shall be effectively sealed to prevent corrosion and also to ensure that the balancing weights of the damper can stand mechanical fly off pull of 500 kgs. The vibration damper shall be capable of being installed and removed from energised line by means of hot line tools without completely separating components. In addition, the clamp shall be capable of being removed and reinstalled on the line of the design torque without shearing or damaging bolts, nuts or capscrews. The damper assembly shall be electrically conductive.

9

Tests

The bidder shall clearly state the testing facilities available at their works to conduct all acceptance and routine testing of materials before finalization and also after acceptance of the tender. The successful tenders shall have to carry out all the tests, such as type test, routine test, acceptance test, as per relevant standard on samples of ordered quantities. The samples for acceptance and type tests quantities by IS will be selected by the purchaser during inspection from offered lot. All the type tests on those samples as per IS shall have to be carried out at NSIC, Baltikuri, Howrah, or ERTL (East) Salt Lake City, Calcutta – 91, in presence of DVC Engineers even if the tenderers submit the test reports of similar samples done earlier. Materials shall be dispatched only after approval of test certificate and granting of dispatch clearance. The test shall be carried out with no additional cost to DVC.

10 Packing and Marking All accessories shall be supplied in strong wooden boxes or crates of approved design with steel loop and band for strength and durability to withstand rough handling during storage. Each package shall be marked on the sides as follows: 1. Name or designation of the consignee to be furnished by the Purchaser. 2. Ultimate destination as required by the purchaser. 3. The items and the respective quantities contained in it (packing list in weatherproof envelope). 4. The net and gross weights of the materials. The marking shall be stenciled indelible ink on each package.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

102

11

Specific Requirements

Sl.

HARDWARE Type Description

Data

1

2

3

Single Tension Hardware for Twin ACSR MOOSE Conductor with Turn Buckle Single Tension Hardware for Twin ACSR MOOSE Conductor without Turn Buckle Single Tension Hardware for single ACSR MOOSE Conductor with Turn Buckle Single Tension Hardware for single ACSR MOOSE Conductor without Turn Buckle Single Suspension Hardware for single ACSR MOOSE drop type 220 KV Rigid Spacer For Twin MOOSE Conductor 25 Dia x 275 mm U-Bolt for swing bus 22 Dia x 76 mm U bolt for gantry side

1250A

220KV 1 2 3 4 5 6 7 8

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

1250A 1250A 1250A 1250A 1250A -

103

SPECIFICATION FOR SOLID CORE POST INSULATORS DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1

Scope

This specification covers design, manufacture, testing at manufacturer’s works and delivery of solid core post insulators for use in 220KV, 132KV and 33KVsystems.

2

Standards

The Insulator covered by this specification should conform to the latest Indian Standard specification IS:2544, IEC-60168,IEC 60273 and IEC-60815. The Standard adopted should be clearly stated in the tender. Where the equipment offered conforms to any other standard, the salient points of difference between the standards adopted and IEC recommendation shall be clearly indicated and the English version of the proposed standard shall be furnished.

3

Manufacturing Requirements

Solid core post type insulators shall consist of a porcelain part permanently secured in a metal base to be mounted on supporting structures. They shall be capable of being mounted upright. They shall be designed to withstand any shocks to which they may be subjected to by operation of the associated equipment. The design of the insulators shall be such that stresses due to expansion and contraction in any part of the insulators shall not lead to deterioration.

3.1

Porcelain

The porcelain shall be of the best electrical quality, homogeneous, free from any laminations, cavities, flaws or imperfections and shall be vitreous and impervious to moisture. Glazing shall be uniform brown colour, smooth surface, free from any blisters, burns or other defects. Its co-efficient of thermal expansion shall be identical with the porcelain body. The glaze shall not crack or chip due to aging under weather conditions or while handling during shipment and creation. The insulator shall have alternate long and short sheds with aerodynamic profile. The shed profile shall also meet the requirements of IEC 60815 for the specified pollution level.

3.2

Cementing

The quality of cement and cementing shall ensure exact spacing, alignment and free from cracks and deterioration due to chemical action. The co-efficient of expansion shall be very near that of porcelain.

3.3

Galvanising

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

104 All ferrous parts shall be hot dip galvanised in accordance with the latest edition of IS: 2633 and IS: 4579. Zinc should be of quality Zn - 99.95 and shall conform to the latest edition of IS - 209. Zinc coating over galvanising surface should not be less than 610 gm/Sq.m and the minimum thickness of coating shall be 85 microns for all items thicker than 6mm. After galvanizing no drilling or welding shall be performed on the galvanised parts. Sodium dichromate treatment shall be provided to avoid formation of white rust after hot dip galvanization.

3.4

Casting

All castings shall be true to pattern, free from defects and of uniform quality and condition. The surface of castings, which do not undergo machining, shall be free from foundry irregularities. The casting shall be tested for NDT, chemical, mechanical and metallographical tests. Iron casting material shall be in accordance with ASTM A 126 class B.

3.5

Nuts, bolts

Every bolt shall be provided with a steel washer under the nut so that part of the threaded portion of the bolts is within the thickness of the parts bolted together. Flat washer shall be circular and of diameter 3.5 times that of bolt and of suitable thickness. Where bolt heads / nuts bear upon the beveled surfaces they shall be provided with square tapered washers of suitable thickness of the parts bolted together. All bolts and nuts shall be of steel with well formed hexagonal heads forged from the solid and shall be hot dip galvanised. The nuts shall be a good fit on the bolt and two clear threads shall show through the nut when it has been finally tightened up.

4

Tests

Quality control of the insulators supplied shall be as per the latest edition of IS:2544, IEC 60168 or any other equivalent International/Indian standard with regard to selection of samples, numbers to be tested, and the tests to be carried out. The tests on individual Unit and also Stack including potential distribution test with the hardware fitting shall have to be carried out. The extent of tests, which will be made shall be stated in the Schedule of Technical Particulars and no departure from this shall be made. Ten(10) copies of certified test certificates that the full supply conforms in materials and workmanship to the specimen tested shall be furnished. Purchaser’s written approval of tests made shall be obtained prior to dispatch. The purchaser may at any time call for optional tests so specified in the standards. The contractor shall arrange such optional tests such as partial discharge test, expeditiously at his own cost. Test reports for such tests shall also be submitted. High frequency electrical routine test on all insulator shells and assembled units shall be performed as per relevant IS or IEC.

4.1

Type Tests

All the type tests are to be carried out in NABL accredited laboratory. The following constitute the type tests : 1 Visual examination 2 Verification of dimension 3 Visible discharge test 4 Impulse voltage withstand test(dry). 5 Wet and dry power frequency voltage withstand test

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

105 6 Temperature cycle test 7 Test for mechanical strength 8 Puncture test 9 Porosity Test 10 Galvanising test

4.2

Routine Tests

The manufacturer shall have the all the Routine Test facilities at his works. The following constitute the Routine tests : 1 Visual examination 2 Mechanical routine test (for Unit and Stack) 3 Electrical routine test.

4.3

Acceptance Tests

The following constitute the acceptance test : 1 Verification of dimensions 2 Temperature cycle test 3 Mechanical strength test 4 Puncture test (for Stack and Unit) 5 Porosity Test 6 Galvanising test

5

Documentation

The following constitute the documentation. 1 Submission and approval procedure is detailed in the SCC. Test reports. 2 Guaranteed technical particulars. 3 Dimensional drawings.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

106

6.Tender Specific Requirements The specific technical requirements for solid core post insulators are as follows: SOLID CORE POST INSULATOR Sl.

Parameter

Values

1 2 220KV SOLID CORE 1 Voltage class in KV 2 Dry and wet one minute power frequency withstand voltage in KVrms 3 Dry impulse withstand positive and negative (KVp)

245 460 1050

4

500 at 146 KVrms

Maximum RIV (in microV) at 1000 Hz phase to ground voltage in KV

5 Minimum visible discharge voltage in KVrms 6 Total minimum cantilever strength in KN 7 Minimum torsional moment KN-m 8 Minimum tensile strength KN 9 Total height of insulator in mm 10 PCD - top in mm 11 PCD - bottom in mm 12 Diameter of holes - top in mm 13 Diameter of holes - bottom in mm 14 Pollution level as per IEC-60815 15 Minimum creepage distance in mm 132KV SOLID CORE 1 Voltage class in KV 2 Dry and wet one minute power frequency withstand voltage in KVp 3 Dry impulse withstand positive and negative (KVp) 4 Minimum visible discharge voltage in KVrms 5 Total minimum cantilever strength in KN 6 Minimum tensile strength KN 7 Minimum torsional moment in KN-m 8 Total height of insulator in mm 9 PCD - top in mm 10 PCD - bottom in mm 11 Diameter of holes - top in mm 12 Diameter of holes - bottom in mm 13 Pollution level as per IEC-60815 14 Minimum creepage distance in mm 33KV SOLID CORE 1 Highest System Voltage in KVrms

3

154 6 4.5 110 2300 127 225/254 M16 18 Heavy (III) 6125 145 275 650 105 6 80 4.5 1500 127 184/200/254 M16 18 Heavy (III) 3625 36

2

Dry and wet one minute power frequency withstand voltage in KVrms 75

3 4 5 6 7 8

Dry impulse withstand positive and negative (KVp) Minimum visible discharge voltage in KVrms Total minimum cantilever strength in KN Minimum tensile strength KN Pollution level as per IEC-60815 Minimum creepage distance in mm

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

170 27 6 50 Heavy (III) 900

107

SPECIFICATION FOR DISC INSULATORS DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT KOLKATA - 700054

1

Scope

The specification covers the design, manufacture, testing at manufacturer’s works and delivery for at work site.

2

Standard

The insulator strings and its components shall conform to the latest edition of the following lndian/International Standards. Where the equipment offered conforms to any other standard, the salient points of difference between the standards adopted and IS/IEC recommendation shall be clearly indicated and the English version of the proposed standard shall be furnished. Sl. No. 1.

Indian Standard

2.

IS:2486

3.

Part- I Part- II Part-III Part-IV IS:2629

4.

IS:2633

IS:731

5. 6.

7. 8.

IS:8263

Title Porcelain insulators for overhead Power lines with a nominal voltage greater than 1000 V Specification for Insulator fittings for Overhead Power Lines with a nominal voltage greater than 1000V General Requirements and Tests Dimensional Requirements Locking Devices Tests for Locking Device Recommended Practice for Hot, Dip Galvanising of iron and steel Methods for testing uniformity of coating of zinc coated articles Thermal Mechanical Performance test and mechanical performance test on string insulator units Residual Strength of String Insulator Units of Glass or Ceramic Material for Overhead Lines after Mechanical Damage of the Dielectric American National Standard for Insulators wet process porcelain and toughened glass suspension type Methods of RI Test of HV insulators

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

International Standard IEC:60383

IEC:60120 IEC:60372

ANSI C29.2 IEC:60437

108

3

String Insulator Requirements •

132 KV : Insulator string suitable for 132 KV voltage shall consist of standard (255 mm x 145 mm) discs & (255 mm x 145 mm) discs ball and socket type, for suspension & tension string respectively. The exposed porcelain parts shall be glazed brown. Unless otherwise specified in the case of special assemblies, 10 Units shall be used on all 132 KV strain string and 9 Units for suspension having ultimate tensile strength of 120 KN and 70 KN respectively.

•

220 KV line : Insulator string suitable for 220 KV voltage shall consist of standard (255 mm x 145 mm) discs & (280 mm x 170 mm) discs ball and socket type, for suspension & tension string respectively. The exposed porcelain parts shall be glazed brown. Unless otherwise specified in the case of special assemblies, 15 Units shall be used on all 220 KV strain string and 14 Units for suspension having ultimate tensile strength of 160 KN and 70 KN respectively.

•

33 KV : Insulator string suitable for 33 KV voltage shall consist of standard (255 mm x 145 mm) discs & (255 mm x 145 mm) discs ball and socket type, for suspension & tension string respectively. The exposed porcelain parts shall be glazed brown. Unless otherwise specified 4 units shall be used for 33KV strain strings and 3 units for 33KV suspension string having ultimate tensile strength of 70kN. Strain insulator discs shall have suitable differentiating marks from suspension discs to facilitate easy identification and to ensure against wrong use. Such marks shall be permanent and either glazed or stamped on insulator discs or embossed on cemented hardware. To ensure against spot loading cap-sockets shall be machined properly for correct ball stud seats. “W” or “R” shaped security clip for locking the ball head of the stud in the socket of the cap conforming to relevant B.S. or I.S. specification shall be supplied. Ball and socket parts refer to 20 mm designation conforming to specification No. BS-137-1960 (Fig. No. 14 to 17) or IS-2486 (Part – II) – 1974 (Fig. No. 10 to 19) or IEC-120.

4

Design ratings

Type

: Conventional ball and socket type.

Diameter

: 255 mm (for 70 KN Disc) – for 132 & 220 KV 255 mm (for 120 KN disc) – for 132 KV 280 mm (for 160 KN Disc) – for 220 KV

Spacing

: 145 mm (for 70 KN Disc) – for 132 & 220 KV 145 mm (for 120 KN disc) – for 132 KV 170 mm (for 160 KN Disc) – 220 KV

Color

: Brown

Surface

: Glaze.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

109

5

String arrangement

No of Discs (for 132 KV)

Electromechanical strength (for 132 KV)

No of Discs (for 220 KV)

Electromechanical strength (for 220 KV)

a)

Suspension Strings for normal suspension locations suitable for 16 mm B & S dia.

9

70 KN

14

70 KN

b)

Tension Strings for normal tension locations suitable for 20 mm B & S dia.

10

120 KN

15

160 KN

c)

Double suspension for special location (crossing) suitable for 16 mm B & S dia.

2x9

70 KN

2 x 14

70 KN

d)

Double tension for special location (crossing) suitable for 20 mm B & S dia.

2 x 10

120 KN

2 x 15

160 KN

e)

Minimum failing load

6

Electrical system data

Shall be equal to electromechanical strength as stated above

132 KV system

220 KV system

a.

Nominal Voltage

:

132 KV

220 KV

b.

Maximum system voltage

:

145 KV

245 KV

c.

BIL (Impulse)

:

650 KV (Peak)

1050 KV (Peak)

d.

Power frequency withstand voltage (Wet)

:

275 KV (rms)

460 KV (rms)

e.

Corona extinction voltage at 50 Hz AC system under dry condition Radio interference voltage

:

105 KV(rms) Phase to earth.

154 KV(rms) Phase to earth.

:

500 Micro volts

Less than 1000 Micro volts at one MHz & 154 KV under dry condition

f.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

110

7

Detailed design requirements

Only porcelain insulator will be acceptable.

7.1

Porcelain

The porcelain shall be of the best electrical quality made by wet process, homogeneous, free from any laminations cavities, flaws or imperfections and shall be vitreous and impervious to moisture. Glazing shall be uniform brown colour, smooth surface, free from any blisters, burns or other defects. Its co-efficient of Thermal expansion shall be identical with the porcelain body. The glaze shall not crack or chip due to ageing under weather conditions or while handling during shipment and erection.

7.2

Cementing

The quality of cement and cementing shall ensure exact spacing, alignment and free from cracks and deterioration due to chemical action. The co-efficient of expansion shall be very near that of porcelain/steel.

7.3

Galvanizing

All ferrous parts shall be hot dip galvanized to conform to IS-2633.

8

Tests

Quality control of the insulators supplied shall be as per the latest edition of IEC 60383 / IS-731 or any other equivalent authoritative standard with regard to selection of samples, numbers to be tested, and the tests to be carried out. The test on individual disc and also string including potential distribution test with the hardware fitting shall have to be carried out. The extent of tests to be conducted, shall be stated in the schedule of Technical particulars and no departure from this shall be made. 10 (ten) copies of certified test certificates that the full supply conforms in materials and workmanship to the specimen tested shall be furnished. Purchaser’s written approval of tests made shall be obtained prior to shipment. The purchaser may at any time call for any optional tests so specified in the standards. The contractor shall arrange such tests expeditiously for which payment will be made. Test reports for such tests shall also be submitted to the purchaser for approval. High frequency electrical routine test on all insulator shells and assembled units shall be performed as per relevant IEC/IS . The bidder shall submit full particulars of the testing facilities available to him. Results of following type tests already carried out on similar supplies shall be furnished in the tender together with copies of Type Test Certificates of a NABL accredited laboratory on similar items. The following constitute the type test: i) On unit disc Insulators a)

Verification of dimensions

:As per IEC :60383

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

111 b)

Thermal mechanical performance test

:As per Annexure-A

c)

Power frequency voltage withstand and flashover test under (i) dry & (ii) wet condition

:As per IEC : 60383

d)

Impulse voltage withstand and flashover test (dry)

:As per IEC : 60383

e)

Visible Discharge test (dry)

:As per IS:731

f)

RIV test (dry)

:As per IEC:60437

g)

Residual strength Test

:As per Annexure-A

h)

Steep wave front Test

:As per Annexure-A

i)

Impact Test

:As per Annexure-A

ii) On the complete Disc Insulator String with Hardware Fittings a)

Power frequency voltage withstand test with arcing horns under wet condition

:As per IEC : 60383

b)

Impulse voltage withstand test under dry condition

:As per IEC: 60383

c)

Impulse voltage flash over test under dry condition

:As per IEC : 60383

d)

Voltage distribution test

:As per Annexure-A

e)

:As per Annexure-A

f)

Corona and RIV test under dry condition (for 220 KV only) Mechanical Strength test

:As per Annexure-A

g)

Vibration test

:As per Annexure-A

For Type Tests which involves the tests on the complete insulator string with hardware fitting, the bidder shall supply the necessary number of sets of hardware fittings at the place of testing free of cost. In case of failure in any type test the bidder is either required to modify the design of the material and successfully carryout all the type tests or to repeat that particular type test at least three times successfully at his own expenses. The following constitute the Acceptance Test : a)

Visual examination

:As per IEC : 60383

b)

Verification of dimensions

:As per IEC : 60383

c)

Temperature cycle test

:As per IEC : 60383

d)

Galvanising test

:As per IEC : 60383

e)

Mechanical performance test

:As per IEC: 60383

f)

Test on locking device for ball and socket coupling

:As per IEC:60372

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

112 g)

Eccentricity test

:As per IEC:60383

h)

IR Measurement

:As per Annexure-A

i)

Electro-mechanical strength test

:As per Annexure-A

j)

Porosity test

:As per IEC : 60383

k)

Puncture test

:As per IEC : 60383

The following constitute the Routine Test : a) Visual Examination

: As per IS: 731

b) Mechanical routine test

: As per IS: 731

c) Electrical routine test

: As per IS: 731

9

Documentation

1) Detailed dimensioned drawings and 2) Guaranteed technical particulars shall constitute the documentation for the specified material.

10

Marking

Each Disc Insulator shall be legibly and indelibly marked with the name of the manufacturer, name of the purchaser i.e ‘DVC’ and month and year of manufacturer. The guaranteed Electromechanical strength shall be indicated in Kilo Newton followed by the word ‘KN’ to facilitate easy identification and to ensure proper use.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

113

Annexure – A 220 KV line 1.

Tests on Complete Strings with Hardware Fittings

1.1

Voltage Distribution Test The voltage across each insulator unit shall be measured by sphere gap method. The result obtained shall be converted into percentage. The voltage across any disc shall not exceed 13% for suspension insulator strings and 14% for tension insulator strings.

1.2

Corona Extinction Voltage Test (Dry) The sample assembly when subjected to power frequency voltage shall have a corona extinction voltage of not less than 154 KV (rms) line to ground under dry condition. There shall be no evidence of corona on any part of the sample. The atmospheric condition during testing shall be recorded and the test results shall be accordingly corrected with suitable correction factor as stipulated in IEC 60383.

1.3

RIV Test (Dry) Under the conditions as specified under (1.2) above, the insulator string along with complete hardware fittings shall have a radio interference voltage level below 1000 micro volts at one MHz when subjected to 50 Hz AC voltage of 154 KV line to ground under dry condition. The test procedure shall be in accordance with IS:8263/IEC 60437.

1.4

Mechanical Strength Test The complete insulator string along with its hardware fitting excluding arcing horn, corona control ring, grading ring and suspension assembly/dead end assembly shall be subjected to a load equal to 50% of the specified minimum ultimate tensile strength (UTS) which shall be increased at a steady rate to 67% of the minimum UTS specified. The load shall be held for five minutes and then removed. After removal of the load, the string components shall not show any visual deformation and it shall be possible to disassemble them by hand. Hand tools may be used to, remove cotter pins and loosen the nuts initially. The string shall then be reassembled and loaded to 50% of UTS and the load shall be further increased at a steady rate till the specified minimum UTS and held for one minute. No fracture should occur during this period. The applied load shall then be increased until the failing load is reached and the value recorded.

1.5

Vibration Test The suspension string shall be tested in suspension mode, and tension string in tension mode itself in laboratory span of minimum 30 metres. In the case of suspension string a load equal to 600 kg shall be applied along the axis of the suspension string by means of turn buckle. The insulator string along with hardware fittings and single conductor tensioned at 35 kN in case of ACSR Zebra conductor and 24 KN in case of ACSR Panther conductor shall be secured with clamps. The system shall be suitable to maintain constant tension on the conductor throughout the duration of the test. Vibration dampers shall not be used on the test span. The conductor shall be vertically vibrated at one of the resonance frequencies of the insulators string (more than 10 Hz) by means of vibration inducing equipment. The peak to peak displacement in mm of vibration at the antinode point, nearest to the string, shall be measured and the same shall not be 1.8 less than 1000/f where f is the frequency of vibration in cycles/sec. The insulator string shall be vibrated for not less than 10 million cycles without any failure. After

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

114 the test the insulators shall be examined for looseness of pins and cap or any crack in the cement. The hardware shall be examined for looseness, fatigue failure and mechanical strength test. There shall be no deterioration of properties of hardware components and insulators after the vibration test. The insulators shall be subjected to the following tests as per relevant standards: Tests Percentage of

Percentage of units to be tested

a)

Temperature cycle test followed by mechanical performance test

60

b)

Puncture test/steep wave front test

40

2.

On Disc Insulator Units

2.1.

Steep Wave Front Test Test following test shall be performed on 10 insulator units in case of disc insulators selected at random from the lot offered for selection of sample for type test. a)

Each insulator unit shall be subjected to five successive positive and negative impulse flashovers with a wave having minimum effective rate of rise of 2500 KV per microseconds.

b)

Each unit shall then be subjected to three dry power frequency voltage flashovers.

Acceptance Criteria An insulator shall be deemed to have met the requirement of this test if, having been successfully subjected to the ten impulse flashovers, the arithmetic mean of the three subsequent dry/power frequency voltage flashover values equals or exceeds 95% of the rated dry power frequency flashover voltage. An insulator shall be deemed to have failed to meet the requirement of above testing if, (a)

It has not flash over when the oscillogram or peak voltage indicator shows a marked reduction in voltage. or

(b)

2.2

Any one of the subsequent three dry power frequency voltage flashover value is less than 80% of the value specified.

Failure of any one unit either in the steep wave front or subsequent low frequency voltage test shall cause for testing on double number of units. Thermal Mechanical Performance Test Thermal Mechanical Performance Test shall be performed in accordance with IEC60383-1 Clause 20 with the following modifications : (1)

The applied mechanical load during this test shall be 70% of the rated electromechanical or mechanical value.

(2)

The acceptance criteria shall be (a)

X greater than or equal to R + 3S.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

115 Where X = Mean value of the individual mechanical failing load. R = Rated electro-mechanical / mechanical failing load. S = Standard deviation.

2.3

(b)

The minimum sample size shall be taken as 20 for disc insulator units.

(c)

The individual electromechanical failing load shall be at least equal to the rated value. Also puncture shall not occur before the ultimate fracture.

Electromechanical/Mechanical Failing Load Test This test shall be performed in accordance with clause 18 and 19 of IEC 383 with the following acceptance (i)

X greater than or equal to R + 3S Where X = Mean value of the electro-mechanical/mechanical failing load. R = Rated electro-mechanical / mechanical failing load. S = Standard deviation.

2.4

2.5

2.6

(ii)

The minimum sample size shall be taken as 20 for disc insulators units. However, for larger lot size, IEC 60591 shall be applicable.

(iii)

The individual electro-mechanical/mechanical failing load shall be at least equal to the rated value. Also electrical puncture shall not occur before the ultimate fracture.

Residual Strength Test The above test shall be performed as per clause 4.4 and 4.5 of IEC 60797 preceded by the temperature cycle test of porcelain disc insulators. The Sample size shall be 25 and the evaluation of the results and acceptance criteria shall be as per clause No. 4.6 of IEC 60797. IR Measurements IR measurement shall be carried out by the instrument operating at 1 KV DC. IR value when measured under fair weather condition, shall not be less than 1000 Mohm. Impact Test The Impact Test shall be carried out in accordance with ANSI-C-29.2 Clause 8.2.8 with the following modification. The breaking point of the pendulum shall be so adjusted that, when released the copper nose will strike the outer rim of the shell or the most protuded rim of the shell squarely in a direction parallel to the axis of the unit and towards the cap. The test specimen shall receive an impact of 7N-m for 120 KN & 10N-m for 160 KN Disc by releasing the pendulum.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

116

ANNEXURE-A 132 KV Line 1.

Tests on Complete Strings with Hardware Fittings:

1.1

Voltage Distribution Test The voltage across each insulator unit shall be measured by sphere gap method. The result obtained shall be converted into percentage. The voltage across any disc shall not exceed 20% for suspension insulator strings and tension insulator strings.

1.2

Mechanical Strength Test The complete insulator string along with its hardware fitting excluding arcing horn, corona control ring, grading ring and suspension assembly/dead end assembly shall be subjected to a load equal to 50% of the specified minimum ultimate tensile strength (UTS) which shall be increased at a steady rate to 67% of the minimum UTS specified. The load shall be held for five minutes and then removed. After removal of the load, the string components shall not show any visual deformation and it shall be possible to disassemble them by hand. Hand tools may be used to, remove cotter pins and loosen the nuts initially. The string shall then be reassembled and loaded to 50% of UTS and the load shall be further increased at a steady rate till the specified minimum UTS and held for one minute. No fracture should occur during this period. The applied load shall then be increased until the failing load is reached and the value recorded.

1.3

Vibration Test The suspension string shall be tested in suspension mode, and tension string in tension mode itself in laboratory span of minimum 30 metres. In the case of suspension string a load equal to 600 kg shall be applied along the axis of the suspension string by means of turn buckle. The insulator string along with hardware fittings and conductor tensioned at 1850 kg in case of ACSR Panther conductor shall be secured with clamps. The system shall be suitable to maintain constant tension conductor throughout the duration of the test. Vibration dampers shall not be used on the test span. The conductor shall be vertically vibrated simultaneously at one of the resonance frequencies of the insulators string (more than 10 Hz) by means of vibration inducing equipment. The peak to peak displacement in mm of vibration at the antinode point, nearest to the string, shall be measured and the same shall not be less than 1000/f1.8 where f is the frequency of vibration in cycles/sec. The insulator string shall be vibrated for not less than 10 million cycles without any failure. After the test the insulators shall be examined for looseness of pins and cap or any crack in the cement. The hardware shall be examined for looseness, fatigue failure and mechanical strength test. There shall be no deterioration of properties of hardware components and insulators after the vibration test. The insulators shall be subjected to the following tests as per relevant standards : Tests Percentage of

Percentage of units to be tested

a)

Temperature cycle test followed by mechanical performance test

60

b)

Puncture test/steep wave front test

40

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

117

2.

On Disc Insulator Units

2.1

Steep Wave Front Test Test following test shall be performed on 10 insulator units in case of disc insulators selected at random from the lot offered for selection of sample for type test. a) Each insulator unit shall be subjected to five successive positive and negative impulse flashovers with a wave having minimum effective rate of rise of 2500 KV per microseconds. b) Each unit shall then be subjected to three dry power frequency voltage flashovers. Acceptance Criteria An insulator shall be deemed to have met the requirement of this test if, having been successfully subjected to the ten impulse flashovers, the arithmetic mean of the three subsequent dry/power frequency voltage flashover values equals or exceeds 95% of the rated dry power frequency flashover voltage. An insulator shall be deemed to have failed to meet the requirement of above testing if, (a) It has not flash over when the oscillogram or peak voltage indicator shows a marked reduction in voltage. or (b) Any one of the subsequent three dry power frequency voltage flashover value is less than 80% of the value specified. Failure of any one unit either in the steep wave front or subsequent low frequency voltage test shall cause for testing on double number of units.

2.2

Thermal Mechanical Performance Test Thermal Mechanical Performance Test shall be performed in accordance with IEC60383-1 Clause 20 with the following modifications : (1) The applied mechanical load during this test shall be 70% of the rated electromechanical or mechanical value. (2) The acceptance criteria shall be (a) X greater than or equal to R + 3S. Where X = Mean value of the individual mechanical failing load. R = Rated electro-mechanical / mechanical failing load. S = Standard deviation. (b) The minimum sample size shall be taken as 20 for disc insulator units. (c) The individual electromechanical failing load shall be at least equal to the rated value. Also puncture shall not occur before the ultimate fracture.

2.3

Electromechanical/Mechanical Failing Load Test This test shall be performed in accordance with clause 18 and 19 of IEC 60383 with the following acceptance

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

118 (i) X greater than or equal to R + 3S Where X = Mean value of the electro-mechanical/mechanical/ failing load. R = Rated electro-mechanical / mechanical failing load. S = Standard deviation. (ii) The minimum sample size shall be taken as 20 for disc insulators units. However, for larger lot size, IEC 60591 shall be applicable. (iii) The individual electro-mechanical/mechanical failing load shall be at least equal to the rated value. Also electrical puncture shall not occur before the ultimate fracture.

2.4

Residual Strength Test The above test shall be performed as per clause 4.4 and 4.5 of IEC 60797 preceded by the temperature cycle test, on both glass and porcelain disc insulators. The Sample size shall be 25 and the evaluation of the results and acceptance criteria shall be as per clause No. 4.6 of IEC 60797.

2.5

IR Measurements IR measurement shall be carried out by the instrument operating at 1 KV DC. IR value when measured under fair weather condition, shall not be less than 1000 Mohm.

2.6

Impact Test The Impact Test shall be carried out in accordance with ANSI-C-29.2 Clause 8.2.8 with the following modification. The breaking point of the pendulum shall be so adjusted that, when released the copper nose will strike the outer rim of the shell or the most protruded rim of the shell squarely in a direction parallel to the axis of the unit and towards the cap.

The test specimen shall receive an impact of 7 N-m for 70 KN and 120 kN Disc by releasing the pendulum.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

119

7

Specific Requirements

The disc insulators shall have the following parameters: DISC INSULATORS Sl.

Description

Parameter

1

2

3

1 2

Type Ball and socket String arrangements for 220KV No. of discs in 220KV suspension strings for normal 14 suspension locations suitable for 16mm ball and socket diameter Electro mechanical strength of discs in 220KV suspension strings for normal suspension locations suitable for 16mm ball 70 kN and socket diameter

a

b

c

No. of discs in 220KV tension strings for normal tension locations suitable for 20mm ball and socket diameter

d

Electro- mechanical strength of discs in 220KV tension strings for normal tension locations suitable for 20mm ball and 160 kN socket diameter

e

No. of discs in 220KV double suspension strings for special locations suitable for 16mm ball and socket diameter

2 x 14

f

Electro-mechanical strength of discs in 220KV double suspension strings for special locations suitable for 16mm ball and socket diameter

70 kN

g

No. of discs in 220KV double tension strings for special locations suitable for 20mm ball and socket diameter

2 x 15

h 3 a

b

15

Electro-mechanical strength of discs in 220KV double tension strings for special locations suitable for 20mm ball and socket 160 kN diameter String arrangements for 132KV No. of discs in 132KV suspension strings for normal 9 suspension locations suitable for 16mm ball and socket diameter Electro mechanical strength of discs in 132KV suspension strings for normal suspension locations suitable for 16mm ball 70 kN and socket diameter

c

No. of discs in 132KV tension strings for normal tension locations suitable for 20mm ball and socket diameter

d

Electro- mechanical strength of discs in 132KV tension strings for normal tension locations suitable for 20mm ball and 120 kN socket diameter

e

No. of discs in 132KV double suspension strings for special locations suitable for 16mm ball and socket diameter

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

10

2x9

120

f

Electro-mechanical strength of discs in 132KV double suspension strings for special locations suitable for 16mm ball and socket diameter

70 kN

Sl.

Description

Parameter

1

2

3

g

No. of discs in 220KV double tension strings for special locations suitable for 20mm ball and socket diameter

2 x 10

h 4 a b c 5 a b c 6 a b c 7 a b c 8 a b c 9 i) a b c ii) a b c iii) a b c iv) a b c

Electro-mechanical strength of discs in 220KV double tension strings for special locations suitable for 20mm ball and socket diameter Diameter for 70kN disc for 120kN disc for 160kN disc Spacing for 70kN disc for 120kN disc for 160kN disc Total creepage distance for 70kN disc for 120kN disc for 160kN disc Protected creepage distance for 70kN disc for 120kN disc for 160kN disc Visible discharge voltage for 70kN disc for 120kN disc for 160kN disc Flashover / withstand test voltage Power frequency (dry) withstand for 70kN disc for 120kN disc for 160kN disc Power frequency (wet) withstand for 70kN disc for 120kN disc for 160kN disc Power frequency dry flashover voltage for 70kN disc for 120kN disc for 160kN disc Power frequency wet flashover voltage for 70kN disc for 120kN disc for 160kN disc

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

120 kN

255 mm 255 mm 280 mm 145 mm 145 mm 170 mm 320 mm 320 mm 330 mm 160 mm 160 mm 165 mm 9 KV 18 KV 18 KV

70 KV 70 KV 72 KV 40 KV 40 KV 42 KV 75 KV 75 KV 78 KV 45 KV 45 KV 48 KV

121

v) a b c vi) a b c

Power frequency puncture voltage for 70kN disc for 120kN disc for 160kN disc Impulse withstand voltage +ve for 70kN disc for 120kN disc for 160kN disc

Sl.

Description

Parameter

1

2

3

vii) a b c

Impulse flashover voltage +ve for 70kN disc for 120kN disc for 160kN disc

115 KV 115 KV 120 KV

110 KV 120 KV 125 KV 110 KV 110 KV 115 KV

Minimum failing load shall be equal to electro-mechanical strength stated.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

122

SPECIFICATION FOR LIGHTING DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1

Scope

This specification covers the equipment required for lighting of substations and its building complex and all approach and peripheral roads in the substation area for both general and emergency use. The equipment covered under this scope includes: 1. Illumination design both indoor and outdoor for the area pertaining to substation area and control building including all connected roads of substation. 2. Manufacture, testing at manufacturer’s Works, packing and delivery at site of light fittings and accessories including, but not limited to the following: (a)

Weather proof - Main Distribution Boards (MLDB), Sub-Distribution Boards (SLDB), Emergency Lighting Distribution Board (ELDB), A.C./D.C. Change Over Board, LILO Boards for Lighting Tower of the Switchyard and Lighting Panels with MCCB/MCBs

(b)

HRC fuses and Miniature Air Circuit Breakers etc for the above panels.

(c)

1.1 KV (E) Grade PVC Cables conforming to IS:1554, Part-I.

(d)

G.I. Conduits with threads and watertight accessories.

(e)

Clamps, fixtures etc. required for holding conduits/light fittings/cables for complete wiring.

(f)

Light fittings as required by this specification and approved design provided with watertight conduit wiring boxes.

2

(g)

Mounting and suspension attachment for switchboard etc.

(h)

Incandescent, fluorescent and sodium/mercury vapor lamps etc as required.

(i)

Switches Plugs and Sockets.

(j)

Metal clad socket outlet with plug and iron clad switches.

(k)

HRC fuses.

(l)

Safety earthing materials.

(m)

Water-tight Junction boxes etc.

Standards

The design, manufacture, testing and performance of the equipment offered and the illumination system shall in general comply with the latest issues including amendments of the following Indian

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

123

(or equivalent IEC) Standards: IS:1913,Part-I - General and safety requirement for luminaries:Tubular Fluorescent lamps. IS:1777 - Industrial luminaries with metal reflectors. IS:4012 – Specification for Dust proof electric lighting fittings. IS:4013 - Dust tight electric lighting fittings. IS:5077 - Decorative lighting outfits. IS:3287 - Industrial lighting fittings with plastic reflectors. IS:3528 - Water proof electric lighting fittings. IS:2418(all relevant parts) – Specification for Tubular fluorescent lamps for General lighting service. IS:1258 - Bayonet lamp holders. IS:3323 - Bi-pin lamp holders for tubular fluorescent lamp. IS:1534 - Ballasts for fluorescent lamps-(Part-I)-For switch start circuit. IS:1569 - Capacitors for use in tubular fluorescent high pressure mercury and low pressure sodium vapour discharge lamp circuit IS:2215 – Specification for Starters for fluorescent lamps. IS:3324 - Holders for starters for tubular fluorescent lamps. IS:10322(all relevant parts)- Specification for Luminaries Conduits, Junction Boxes IS:9537(Part 2) – Conduits for electrical installations, Part 2- Rigid steel conduits IS:3480 - Flexible steel conduit for electrical wiring. IS:2667 - Fittings for rigid steel conduits for electrical wiring. IS:3837 - Accessories for rigid steel conduits for electrical wiring. IS:4649 - Adapters for flexible steel conduits. IS:14772 – General requirements for enclosures for accessories for household and similar fixed electrical installations-Specifications Lighting Panels IS:13947 – Specification for low voltage switchgear and control gear (all relevant parts). IS:13703(all relevant parts)-LV fuses for voltages not exceeding 1000 V AC or 1500 V DC. IS:5082 - Wrought aluminium and Al. alloys, bars, rods, tubes and sections for electrical

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

124

purposes. IS:8828 – Electrical accessories :Circuit Breakers for over current protection for household and similar installations. Cables IS:694 - PVC insulated cables for working voltages (1977) upto and including 1100 V. Electrical IS:1293 – Plugs and Socket- Outlets of rated voltage upto and including 250 volts and rated current upto and including 16 Amps-Specification. IS:3854 - Switches for domestic and similar purposes. IS:5216(Part I and II) – Recommendations on safety procedures and practices in electrical work. IS:732 - Code of practice for Electrical wiring installations . IS:3646 - Code of practice for interior illumination (Part I, II & III). IS:800 - Code of practice for general construction in steel. IS:1944 - Code of practice for lighting of public thoroughfares. IS:2633 - Methods for testing uniformity of coating of zinc coated articles. IS:6005 - Code of practice for phosphating iron and steel. IS:3043 – Code of practice for earthing. IS:6665 - Code of practice for Industrial lighting.

3

Illumination Level Requirement

The Tenderer shall design the entire lighting system layout including the accessories and panels etc on the basis of illumination levels of different areas indicated below but not limited to the following : 1. Area:

Control room and relay room including vertical faces of control panels and relay panels. Average illumination level in Lux (general lighting): 300; Quality class of glare restriction: 1 Average illumination level in Lux (emergency lighting): 20

2. Area: Carrier room including vertical faces of carrier panels, Engineer’s room, Office room. Average illumination level in Lux (general lighting): 200; Quality class of glare restriction: 1 Average illumination level in Lux (emergency lighting): 10 3. Area: Battery room. Average illumination level in Lux (general lighting): 75; Quality class of glare restriction: 3 ;Average illumination level in Lux (emergency lighting): 10. 4. Area: Miscellaneous room, switch room, store room. Average illumination level in Lux (general lighting): 100 Quality class of glare restriction: 2 Average illumination level in Lux (emergency lighting): 10

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

125

5. Area: Maintenance room. Average illumination level in Lux (general lighting): 200 Quality class of glare restriction: 1; Average illumination level in Lux (emergency lighting): 5. 6. Area: Bath room. Average illumination level in Lux (general lighting): 50 Quality class of glare restriction: 2; Average illumination level in Lux (emergency lighting): 5. 7. Area: Other rooms. Average illumination level in Lux (general lighting): 150 Quality class of glare restriction: 1; Average illumination level in Lux (emergency lighting): 5 8. Area: Corridor, staircase. Average illumination level in Lux (general lighting): 75 Quality class of glare restriction: 2; Average illumination level in Lux (emergency lighting): 5. 9. Area: Cable operating floor, mezzanine floor. Average illumination level in Lux (general lighting): 50 Quality class of glare restriction:2; Average illumination level in Lux (emergency lighting): 5. 10. Area: Outdoor switchyard (except transformers, breakers) and boundary wall. Average illumination level in Lux (general lighting): 20 Quality class of glare restriction: 2 Average illumination level in Lux (emergency lighting): 5. 11. Area: Transformers and breakers. Average illumination level in Lux (general lighting): 100 Quality class of glare restriction: -Average illumination level in Lux (emergency lighting): 12. Area: Approach road. Average illumination level in Lux (general lighting): 20 Quality class of glare restriction: -Average illumination level in Lux (emergency lighting): 13. Area: Garage. Average illumination level in Lux (general lighting): 20 Quality class of glare restriction: -Average illumination level in Lux (emergency lighting): Note : i) Localised lighting shall be provided to get the highest illumination level over and near the main equipment e.g. CB, Isolators, CT, PT, LA etc. ii) a) Detail drg. showing arrangement of luminaries, conduit wiring, mounting, suspension arrangement of all luminaries and board etc. to be submitted. b) Complete illumination design and calculation to be submitted. c) All standard luminaries etc. technical doc., leaflet etc. to be submitted.

3.1

Completeness of Supply

All items shall be offered complete with all parts, mountings, fixtures and standard accessories etc., which are necessary for efficient and proper illumination. Any structure of fittings specially required shall also be included in the scope. Such parts shall be deemed to be within the scope of this specification whether specially mentioned or not.

3.2

Materials and Workmanship

All equipment and accessories to be supplied under this specification shall conform to relevant IS specification and free from defects and imperfection and of approved grade and classification. The makes of all the equipment and accessories shall clearly be indicated in the tender. All equipment shall be guaranteed by the Tenderer to be free from any defect due to faulty design, materials and/or workmanship.

3.3

Erection Tools & Tackles

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

126 All erection tools and tackles as may be required for the complete installation work shall be supplied by the contractor.

3.4

Supply System

1. AC System : 3 phase, 4 wire AC supply. (a) AC Supply for auxiliaries - 3 phase, 4 wire, 415 Volts + 10%, Fault MVA - 25 MVA at 415 Volts. (b) System frequency - 50 cycles per second + 3%. (c) System grounding - Effectively grounded. (d) The lighting distribution boards shall be fed from 415 Volts board through MCCBs located within the misc. board room. (e) Fault level - 25 KA. 2. Emergency lighting: 2 wire DC Supply. (a) System Voltage - 250 Volts ± 10% from DC board located within the Misc. panel room. (b) Fault level - 15 KA.

3.5

Tender Drawings

The Tenderer shall furnish a design and drawings (along with the tender) indicating therein the location and type of light fittings and also locations of Main Distribution Boards, Sub-distribution Boards, Lighting Panels, Power Plugs, Lighting Plugs etc. Panels details shall also be stated clearly. The final design and quantity, however, will be finished and approved during execution of contract on the basis of approved Switchyard layout and control room building. Standard literature of all type of fittings, switches, power receptacles, MCCBs, MCBs, Lamps and all other materials offered, shall also be submitted a long with the tender.

3.6

Detailed Design

General scheme: Tentative provisions have been made for the following feeders for Main Distribution Boards from the AC Panel located in the Misc. Panel Room of the control building: 1. For control building lighting (excluding peripheral lighting) : 2 (two) 63 Amps, 415 Volts, 3 phase, 4 wire feeders. 2. For Sub-Station lighting (including gate and road lighting and boundary wall : 2 (two) Nos. 100 Amps, 415 Volts, 3 phase, 4 wire feeders. 3. Power plug : (a) 2 (two) Nos. 63 Amps, 415 Volts, 3 phase, 4 wire feeder for 220 KV switchyard. (b) 1 (one) Nos. 63 Amps, 415 Volts, 3 phase, 4 wire feeder for 33 KV switchyard. (c) 1 (one) No.100 Amps, 415 Volts, 3 phase, 4 wire feeder for filter machine at transformer yard. (d) 1 (one) No. 63 Amps, 415 Volts, 3 phase, 4 wire feeder for maintenance shop. 4. Emergency Lighting : 2 (two) Nos. 50 Amps, 220 Volts (DC) 2 wire feeder. The main distribution boards shall be sub-divided in several sub-distribution boards/lighting panels. The total load (including lighting load and lighting plugs) per SLDB lighting panel shall never exceed 20 KW (3 phase) and total lighting circuits in each lighting panels shall never exceed 10 (ten) numbers. Main distribution board shall be floor mounted. Lighting panels shall be wall /

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

127

column mounted. However, the above provisions, may be changed as per design requirement.

3.6.1 Power Receptacle Connections The 3-phase power supply shall be provided for each power receptacle from main distribution boards. Each main distribution board shall have at least 1 No. 63 Amps power receptacle connections. There shall be total 4 Nos. such receptacles suitably distributed over the switchyard.

3.6.2 Plug Points There shall be at least 1 No. 15/5 Amp. Socket outlet with separate control switch in each board. At least 10 Nos. 15 Amps combined socket outlets are to be provided in the control building.

3.6.3 Power point for Air-Conditioners The control room, relay room, carrier room and the Engineer’s room will be air-conditioned with unit type (or split type) air-conditioners. A separate board with 15 Amp. Plug point with MCB and fuses shall be provided for each unit. All these boards shall be fed from separate 3-phase AC feeder along with necessary distribution board.

3.6.4 Fans 1400mm sweep ceiling fans and 225mm / 300mm heavy duty Exhaust fan would be fixed at various locations of the control building. Both supply and erection of all fans would be within Contractor’s scope. Exact location/number of fans would be finalised at the time of final design.

3.6.5 Emergency Lighting (Change-over Board) The contractor shall supply 1 No. (2x50) Amps rating with 2 ways single phase AC/DC change over board (ELDB). For emergency lighting the contractor shall lay the cable (PVC heavy duty armoured) for AC/DC supply from the AC/DC change over board to respective emergency lighting panels. The termination of these cables shall be the responsibility of the contractor. A.C. and DC supply shall not overlap during changeover. Detail scheme should be submitted along-with the tender. Suitable arrangement shall be provided to have annunciation for change over at the purchaser’s control panel. The emergency lighting AC/DC change over load shall be fed from: 1. AC power shall be fed from single phase feeder from AC board located in Misc. board room. 2. The DC power (220 Volts) will be fed from the DC board located in Misc. Board room. From the MDBs the Contractor will run armoured PVC cable upto lighting panels and the PVC wires in G.I. conduits upto lighting plug points etc. The contractor then shall finally locate and decide the actual number of LPs and group points in such a way that the incoming load for each LP does not exceed the rated amperage capacity of the corresponding miniature circuit breaker located at MDB for feeding the LP. And each group light points i.e. sub-circuits the load per circuit must not exceed 6 Amps. In selecting the size of the cables and wires for different circuits from MDBs to the furthest load point the following considerations must be taken into account : 1. Current carrying capacity.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

128 2. Voltages drop.

3.6.6 Current carrying capacity When selecting the size of the cables from MDBs to LP, it must be considered as if the LPs are carrying full rated current. When selecting the size of the wire for sub-circuits it must be considered as if the sub-circuits are fully loaded (6 Amps.). Minimum cable size per lighting sub-circuit shall not be less than 3/20 (1.5sq.mm min) copper wires. Minimum cable size for 15 Amps. power socket receptacle connection shall not be less than 7/22 (2.5sq.mm min). The sizes of cables such found must be de-rated to the factor considering ambient temperature of 50 oC, grouping factor, laid in conduit etc.

3.6.7 Voltage Drop For cable size found by the above method must be checked up for voltage drop to satisfy the following : Voltage drop from MDBs to the farthest load point must not exceed 3 (three) Volts. The above voltage drop requirement must be strictly adhered to. No other standard for voltage drop is acceptable to the Purchaser.

3.6.8 PVC Wires in Conduits This should be as per IS 694 but more than 40% of the inside space of the conduit should not be covered by the wires drawn through it. The contractor must furnish calculations for voltage drop in different sub-mains and sub-circuits. The contractor should indicate the derating factor used for higher temperature (50 oC) and on a single line diagram should indicate the size of the wires used and voltage drop in each sub-mains and sub-circuits (load line diagram).

3.6.9 Luminaries Following type of luminaries shall be used in different rooms of control room building and switchyards : 1. Location: Switchyard area. Type of luminaries for general lighting: Flood light luminaries suitable for 2x400W / 1x400W / 2x250W HPSV lamps. 2. Location: Roads. Type of luminaries for general lighting: Street light luminaries suitable for 1x 150W/1x 250W HPSV lamps to be fitted on swag pole. 3. Location: Gate. Type of luminaries for general lighting: Aesthetically pleasing post top luminaries suitable for 70W HPSV/HPMV lamps. 4. Location: Control room, carrier room, Engineers’ room and waiting room. Type of luminaries for general lighting: Indoor decorative recess mounted luminaries with mirror optics reflector suitable for 2x40W fluorescent lamp. Type of luminaries for emergency lighting : Decorative recess mounted down light suitable for 1x60W/1x100W reflector lamp / equivalent power saving type. 5. Location: Corridor, portico, staircase and office room. Type of luminaries for general lighting: Ceiling mounted indoor decorative luminaries suitable for 2x40W / 1x40W fluorescent lamps /

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

129

power saving CFL. Type of luminaries for emergency lighting: Bulk head luminaries suitable for 60W GLS lamps. 6. Location: Miscellaneous panel room, maintenance room, store room and toilet. Type of luminaries for general lighting: Ceiling mounted, corrosion resistant, industrial luminaries suitable for 2x40W fluorescent lamps / power saving CFL. Type of luminaries for emergency lighting: Bulk head luminaries suitable for 60W GLS lamps. 7. Location: Battery room. Type of luminaries for general lighting: Ceiling mounted, corrosion resistant, industrial luminaries suitable for 2x40W fluorescent lamps / power saving CFL. Type of luminaries for emergency lighting: Corrosion resistant bulk head luminaries suitable for 60W GLS lamps. 8. Location: Peripheral area of control room building. Type of luminaries for general lighting: Flood light luminaries suitable for 70W/125W, HPSV / HPMV lamps. Note: Make and type of all the luminaries and lamps to be used in different area both for general lighting and emergency lighting along with detailed literature must be submitted along with the tender.

3.6.10 Lamp All tungsten filament lamps shall be rated for 250 Volts, gas filled clear. The filament shall be designed such that the lamps can be fitted in any position though normally these will be fitted in “base up” position. All fluorescent tubes shall be of 250 Volts. The accessories shall be housed in the lighting fixture. The colour of the lamp shall be cool white. All lamps shall be able to withstand + 10% variation of the rated voltage and + 3% of the rated frequency. The performance shall not be affected for such variation. Make and type of the lamps for different areas should be clearly stated in the tender without whom the tender is liable for rejection.

3.6.11 Plugs, Sockets & Switches 60 Amps, 3 pin and earth, metal clad, socket outlet and plug for power connection shall be dust and weather proof design. The socket should have a screwed cover. 60 Amps, MCCB with HRC cartridge fuse shall be dust and weather proof. This switch shall be used with 60 Amps. Socket outlet mentioned above and should be installed near the 60 Amps socket on a combined structure. 5/15 Amps. piano type switches for mounting on sheet steel switch boards with Bakelite cover. These will be used for controlling lamps, fans, plug points etc. in the small room. The combined units of 5/15 Amps. 5-pin plug and socket outlet along with switches shall be enclosed in a metallic cover.

3.6.12

Wiring Materials & Accessories

The PVC wires and cables shall be of 1100 volts grade. The wiring should be of open conduit type with G.I. conduits of suitable size. For the battery room, the conduits and other accessories, which are liable to corrosion, should be painted with acid proof painting before erection. The exhaust fans should be of fairly quiet type. AC and DC wires should never run through the same conduit.The galvanised steel conduits of 14

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

130

SWG and the weather proof accessories shall be of first class quality subject to the approval of purchaser and should bear ISI mark. All mounting and suspension attachments, clamps, fixtures and accessories etc. should be supplied by the contractor and should be suitable for G.L. conduit wiring (ET). Wiring for different rooms: i) Concealed wiring shall be done in the rooms having false ceiling i.e. control room, engineer’s room, computer room / record room. Conduit wiring shall be done above false ceiling area and concealed wiring shall be done below false ceiling area as per design / layout approved by DVC. ii) The rooms where no false ceiling is provided G.I conduit surface wiring shall be followed. The Tenderer shall assess the quantity of all wiring materials and accessories required for complete illumination system and quote accordingly.

4

Boards & Panels

4.1

Main Distribution Boards

4.1.1 Indoor type The main distribution boards (MDB) shall be fabricated from 3 mm steel sheets and shall consist of the following: 1. 2. 3. 4.

Incomer MCCB. Outgoing MCCB/MCB. Detachable blank circuit label to be inscribed at site. Caution board.

The equipment shall be housed inside a sheet steel cubicle with hinged front access door and the board shall be complete with Aluminium busbar, of size not less than 50x6 mm, in an enclosed busbar chamber, floor pedestals including iron base for floor mounting, necessary bolts, nuts etc. Suitable provision for terminating purchaser’s cables should be made in MDB either for the bottom or top entry to be decided later. Necessary cable boxes, glands, etc. shall be supplied by the contractor. Termination of the cable at the MDB end shall be the responsibility of the contractor.

4.1.2

Outdoor type

Same as Indoor except suitable for outdoor installation i.e. with suitable hood and double doors with waterproof gaskets. Cable entry shall be from bottom only. Degree of protection shall be IP-55.

4.2

SLDB/Lighting Boards

4.2.1 Indoor type The lighting panels (protection of panel not less than IP 42) shall be fabricated from sheets steel and shall consist of the following : 1. 2. 3. 4.

Incomer isolator. Outgoing MCBs. Caution board. Detachable blank circuit label to be inscribed at site.

The equipment shall be housed inside a sheet steel cubicle with hinged front access door and the board should be complete with Aluminium / Cu bus bar of suitable size. The board should also be provided with fixtures and nuts, bolts, washers etc. for either wall or column mounting to be decided later. Such indoor type SLDB indicated in schedule of items may be of reputed make like Havell’s,

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

131

Lagrand etc. / equivalent, subject to approval of DVC.

4.2.2 Outdoor type Same as Indoor type except suitable for outdoor installation (Protection of Panel IP 55) i.e. with suitable canopy, double door with watertight gasket etc. Cable entry from bottom only and the panels shall be fabricated from 3mm thick sheet steel.

4.2.3: Loop-in-loop-out J.B: LILO Box (Out door type with IP-55) made of sheet steel (CRCA), min. 2mm thickness, having the following and design approved by DVC, i) 25A terminal block for Loop-in-loop-out of cable. ii) Fuse with link for connection to street light etc.

4.3

Lighting Transformer

75KVA lighting transformer dry type, 3 phase, 50 Hz, 415V/415V Dyn, Class - H insulation suitable for operating temperature of 100 oC. The above transformer shall be housed indoor.

4.4

AC/DC Changeover Board (Emergency Lighting)

The distribution board for emergency lighting shall be fabricated from 2 mm steel sheet and consisting of AC/DC MCCBs of suitable capacity, AC/DC contactor, Aux. contactor, Timer, Push button, Voltmeter indicating etc., one caution board and one detachment blank circuit label to be inscribed at site. The equipment shall be housed inside a sheet steel cubicle with hinged access door. The 60 Amp. bus bars shall be housed in a suitable bus bar chamber. The contactor shall supply all accessories for wall/floor mounting of the cubicle.

4.5

General Consideration

During detail illumination design every effort shall be made to optimise the total power requirement and to locate all the luminaries at convenient places. If needed, the Tenderer shall be prepared to shift the positions for better efficiency and utilisation and case of maintenance without any extra cost. If desired by the purchaser, the Tenderer shall be prepared to supply an install additional luminaries and other equipment complete with all accessories at the quoted unit prices. Suppliers should therefore indicate unit prices for all materials and installation charges over and above as has been indicated in the schedule of prices, if required.

4.6

Maintenance Factor

During illumination design, the maintenance factor shall never be taken more than 0.7 in the standard formula : F = (E x A)/(CU x MF) Where F = Total luminous flux to be installed in 1 M. E = Illumination required in Lux. A = Area of floor to be illuminated in Sq. Meter CU = Co-efficient of utilisation. MF = Maintenance Factor. Dust proof fittings and water tight fittings shall be provided wherever the layout shall call for the same and the general type fittings shall not be acceptable in those special areas. The type of fittings at different areas of the complex shall clearly be indicated in the relevant schedules along with detailed literature of the same.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

132

4.7

Earthing of the Installation

Two main earth-wires of suitable size shall be laid from the purchaser’s earthing bus provided in the control room/switchyard to each distribution boards by the contractor. To those earthing leads ironclad switches, bus bar chambers etc. would be connected. The earth pin of all socket outlets shall be connected to the general earthing system by means of an earth continuity conductor of suitable size either running inside the conduit or over the surface. G.I. shall ground outdoor lighting/junction boxes flat to the nearest ground grid.

4.8

Contract Drawings & Literature

The contractor shall submit 4 (four) copies of the following drawings and literature for Purchaser’s approval : 1. Single line diagram of lighting scheme. 2. Detail drawing showing arrangement of luminaries, conduit wiring, mounting and suspension arrangement of all luminaries and boards. 3. Complete illumination design and calculation indicating the utilisation factor considered for each type of luminaries. 4. Details drawing of all accessories, fittings and boards. 5. Standard literature of all luminaries and lamps. 6. Any other drawing/literature as will be required by the purchaser. 7. After final erection and testing, the contractor shall supply ten (10) copies of each of the approved drawing along with a set of reproducible. 8. Ten (10) copies of erection and maintenance manual shall also be submitted.

5 5.1

Tests Tests of Equipment and Materials

All the MDBs, LDBs and other equipment will be tested as per relevant IS. Polar distribution curves and other type tests reports of different type of luminaries shall be submitted. Test certificate for lumen output and characteristic curves of different lamps are also to be submitted. Four (4) copies of all the test reports shall be submitted before despatch of materials.

5.2

Testing of the Installation

The following tests shall be done on the installation and test reports in triplicate shall be submitted after completion of the installation. The wiring of the MDBs and lighting panels shall withstand an applied voltage test of 2500 volts for 1 minute. Insulation resistance test : As per IE Rule No. 60.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

133 Earth resistance tests : The final earth resistance as measured by a suitable earth tester between the earth electrodes and any point on earth continuity system shall not exceed 1 (one) Ohm. Earth continuity and mains conductors : The tests shall be in accordance with IE Rule No. 61. Testing of polarity of single pole switches : The contractor shall ensure that all single pole non-linked switches and single phase breakers are connected to the live wire of the system.

6

Handing Over

After completion of installation , illumination measurement of Lux shall be done by Lux level meter (Lux level meter to be arranged by the contractor at his cost) at each decided point in presence of purchaser’s Engineer and to be noted. If the Lux levels are found to be less than what was guaranteed in tender, additional light fittings along with all accessories are to be supplied and installed by the contractor without any additional cost to DVC. The illumination system will only be taken over after desired lux level mentioned in finally approved designs attained.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

134

SPECIFICATION FOR JUNCTION BOXES & OUTDOOR PANELS DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1

Scope

This specification covers the design, manufacture, testing at manufacture’s works, packing and delivery of outdoor type weather proof panels and junction boxes (JB).

2

Applicable Standards

The item shall conform to the latest edition of the following lndian/International Standards. Where the equipment offered conforms to any other standard, the salient points of difference between the standards adopted and IS/IEC recommendation shall be clearly indicated and the English version of the proposed standard shall be furnished. •

IS 13947 (Part 1): Specification for Low voltage switchgear and control gear - general rules.

•

IS 5039: Distribution feeder pillars for voltages not exceeding 1000Vac / 1200Vdc.

•

IS 8623: Specification for low voltage switchgear and control gear assemblies.

•

IEC 60439 (all relevant parts): Low voltage switchgear and control gear assemblies.

•

IS 13703 (All parts): Specification for low voltage fuses for voltages not exceeding 1000 V AC and 1500 V DC

3

Manufacturing Requirements

Outdoor weather proof panel/ box shall be of sheet steel enclosure and shall be dust, water and vermin proof. The thickness of sheet steel shall be 2 mm cold rolled or 2.5 mm hot rolled. The box shall be properly braced to prevent wobbling. There shall be sufficient reinforcement to provide level surfaces, resistance to vibrations and rigidity during transportation and installation. All enclosures shall provide a degree of protection of not less than IP55 as per IS 13947. Evidence of testing shall be in the form of type test reports. The panel shall be free standing floor mount type and the junction box shall be pedestal mount type. They shall have hinged doors with padlocking arrangement. All doors, removable covers and plates shall be gasketed all round with suitable profiled EPDM gaskets. The distance between two hinges shall be adequate to ensure uniform sealing pressure against atmosphere. All gas-keted surfaces shall be smooth, straight and reinforced if necessary to minimize distortion and to make a

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

135

tight seal. The quality of gaskets shall be such that it does not get cracked during ten years of operation of the equipment or its major overhaul whichever is earlier. Ventilating louvers, if provided, shall be with screens and filters. The screen shall be fine wire mesh made of brass. All panels / boxes shall be designed for the entry of cables from the bottom by means of weatherproof and dust proof connections. Panels/ boxes shall be designed with generous clearance to avoid interference between the wiring entering from below and any terminal blocks or accessories mounted within the housing. A suitable undrilled cable gland plate projecting at least 150 mm above the base of the housing shall be provided for this purpose. The gland shall project at least 25 mm above the gland plate to prevent entry of moisture in the cable trench. Each panels/ boxes shall be provided with two earthing pads to receive 75mm x 12mm or 50mm x 6mm GS flat. The connection shall be bolted type with 2 bolts per pad. The hinged door shall be provided with danger plate and internal wiring diagram pasted on the inside of the door. The front label shall be on a 3 mm thick plastic plate with white letters engraved on black background.

4

Terminal Blocks

Terminal blocks shall be 1100V grade and have continuous rating to carry the maximum expected current on the terminals. These shall be moulded, complete with insulating barriers, stud type terminals, complete with washers, nuts and lock nuts. The terminal shall be such that maximum contact area is achieved when a cable is terminated. The terminal shall have a locking characteristic to prevent cable from escaping from terminal clamp unless it is done intentionally. The conducting part in contact with the cable shall preferably be tinned or silver plated. However, nickel plated copper or zinc plated steel shall also be acceptable. The terminal blocks shall be of extensible design. The terminal blocks shall have locking arrangement to prevent its escape from the mounting rails. Terminal block design shall include a white fiber marking strip. Markings on terminal strips shall correspond to numbers on wiring diagrams. The terminal blocks shall be fully enclosed with removable covers of transparent, non-deteriorating type plastic material. Insulating barriers shall be provided between the terminal blocks. There barriers shall not hinder the operator from carrying out the wiring without removing barriers. The arrangement shall be such that it is possible to safely connect or disconnect terminals on the live circuits and replace fuse links when the cabinet is live. Space shall be provided for mounting 20% spare terminal blocks on each junction box. There shall be a minimum clearance of 250 mm between the first/bottom row of terminal blocks and the associated cable gland plate. Clearance between adjacent rows of terminal blocks shall be a minimum of 150 mm.

5

Tests

5.1

Type Tests

The panels/ boxes shall have been type tested for IP 55 degree of protection as per IS : 13947. The bidder shall furnish the type test report at contract stage. In case the Test reports are more than five years old, fresh testing has to be conducted and report submitted. The following tests shall also performed on the junction boxes: 1. 2.5 KV withstand for one minute. 2. Insulation Resistance. 3. Functional tests.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

136

5.2

Routine Tests

The Junction Boxes shall be subjected to the following routine tests as per IS : 5039: 1. 2.5KV withstand for one minute. 2. Check for wiring. 3. Visual and dimensional check. 4. Check for paint.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

137

6

Tender Specific Requirements

The specific technical requirements Junction Box are as follows: OUTDOOR WEATHER PROOF PANEL & JUNCTION BOX Sl.

Description

Parameter

1

2

3

1 2

Installation Design ambient air temperature

3

Thickness of sheet steel

4

Degree of protection

5

Size of terminating wires

Outdoors 50°C At least 2.5 mm hot rolled or 2 mm cold rolled IP 55 as per IS 13947 6 sq.mm for 1A secondary CT terminations, 10 sq.mm for 5A secondary CT terminations, 25 and 10 sq.mm for power cable terminations, 2.5 sq.mm for other control cable terminations

6

Wire type

stranded copper / aluminium

7 8

Terminal blocks Earthlinks

Elmex or approved make As required

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

138

SPECIFICATION FOR SAFETY EQUIPMENT DAMODAR VALLEY CORPORATION ELECTRICITY DEPARTMENT VIP ROAD KOLKATA - 700054

1

Scope

This Specification covers the design, manufacture, testing at manufacturer’s Works, supply and delivery of safety equipment like fire extinguishers and insulating mats.

2

Standard

The equipment covered by this specification shall, unless otherwise specified, conform to the latest edition of the following: 1. IS 2171 2. IS 2878 3. IS 2584 4. IS 8437 5. IS 15652 6. Guidelines of the Tariff Advisory Committee. Wherever the requirements in these specifications are in conflict with any of the above document, the requirements under this specification shall be binding.

3

Extinguishers

1

For electrical equipment, only extinguishers expelling dry powder or carbon dioxide (without metal horn) shall be used.

2

The extinguishers will be portable and freestanding type.

3

Portable extinguishers shall be provided with suitable clamps for mounting on walls else they shall be provided with rollers.

4

They shall be capable of discharging freely and completely in upright position.

5

Instructions for operation shall be on the body of the equipment.

6

All extinguishers shall be painted with durable enamel paint of a colour conforming to the above standards.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

139 7

4

All extinguishers shall be ISI marked.

Insulating Mats

4.1 General Requirements 4.1.1 General properties: 1)

The mat shall be made from insulating material, free from any insertions leading to deterioration of insulating properties.

2)

Upper surface of insulating mat should have small aberration (rough surface) without edges. The lower surface should be plain.

4.1.2 Dimension 1) 2) 3)

The thickness of the mat shall not be less than 2.0 mm. The length of the mat should be a multiple of 5 m. (minimum). Width shall not be less than 1000 mm. ± 20 mm.

4.1.3 Colour The colour shall be mutually decided between purchaser and manufacturer during design engineering stage . However no colour with metallic derivatives shall be used.

4.1.4 Finish The material shall be free from blisters, pin holes, cracks, embedded foreign matter other defects which may impair its serviceability when visually examined.

and

4.1.5 Physical Properties Tensile Strength and Elongation : The tensile strength and elongation of the mat shall be as follows :a) Tensile strength - 15 N / mm2 (Min) b) Elongation at break – 250% (Min)

4.1.6 Ageing properties The deterioration in tensile strength and elongation of the mat at break, when subjected to ageing for 168 hrs. at 70º C + 10º C shall not exceed the following limit of the corresponding values obtained before ageing. Tensile strength – (-) 25% to (+) 10% Elongation at break – (-) 25% to (+) 10%

4.1.7 Effects of Acid, Alkalines, Diesel and Transformer Oil Effects of acid , alkalines, diesel and transformer oil resulting in mechanical and chemical damage on mat will be determined by measuring tensile strength and elongation. The respective test value should be within (+)/ (-) 20% of the original value.

4.1.8 Electrical Properties

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

140

4.1.9

1)

Insulation Resistance with water - Insulation resistance of the mat in wet condition will be 100000 M Ohms minimum when measured with 5 KV Megger or 1000000 M Ohms with 500 volt Megger.

2)

Leakage Current - The leakage current of the mat, measured as per IStested at a voltage of 6.6 KVAC should be below 10 mA.

3)

Breakdown Voltage - The breakdown voltage of the mat measured as per IS: 2584, should not be less than 30 KV AC.

4)

Dielectric Strength - The mat shall withstand a test voltage of 10 KV AC, when tested as per IS-2584 and shall not puncture or become appreciably warm at any spot or show any evidence of weakness. For type test, the voltage should be applied for 3 minutes and for acceptance test the voltage should be applied for 1 min.

8437,

Flammability

Flame Retardance Test - The fire should extinguish within 5 seconds after removal of the blue flame in which the test piece cut from the matting is held.

4.1.10

Sample

The Contractor shall arrange to submit one set of sample of the item offered for Purchaser’s approval prior to taking up of the manufacturing work. However, such submission of sample shall be without any cost implication or any other obligation.

4.2 Packing The material should be rolled smoothly on hollow Mandrel either made of hard card board or wasted plastic of suitable diameter. The material should be bound tightly and the edges of top most layer should not shift from the edge of bottom most layer by more than 75 mm. The roll should be clamped at two places with the help of plastic unidirectional tape & clamps. Gunny / jute material should be used for packing covered by proper plastic bag having lining of suitable fabrics to avoid any kind of damage to the material.

4.3 Tests 4.3.1

Type Tests

All tests specified as type tests in IS 15652 shall constitute the type tests for this specification also.

4.3.2

Routine Tests

The following shall constitute the routine tests: 1) Dimensions, shape, thickness. 2) Tensile strength and elongation. 3) Insulation resistance. 4) Leakage current.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

141 5) AC di-electric strength. 6) AC proof voltage.

4.3.3

Acceptance Tests

All tests indicated as routine tests shall constitute the acceptance tests.

4.4 Documents The following drawings and documents shall form part of the offer: 1) Guaranteed technical particulars. 2) Dimensional drawing of the mat and packing mandrel. 3) Notes and instructions for installation. ...... PTO for specific requirements.

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

142

5

Specific Requirements SAFETY EQUIPMENT

Sl.

Description

Type

1

2

3

Fire Extinguishers 1 6.5kg, Carbon dioxide, as per IS:2878 2 4.5kg, Carbon dioxide as per IS:2878 3 25kg, Dry powder as per IS:2171 4 10kg, Dry powder as per IS:2171 Insulating Mat 1 Class 2 Ambient temperature range 3 Tensile strength in N/mm2 4 % Elongation 5 Tensile strength in N/mm2 after ageing 6 % Elongation after ageing

BID DOCUMENT VOL.-2, PSR SECTION, ELECTRICITY DEPT.

Trolley Portable Trolley Wall hanging A -10oC to 50oC 15 250 (min) (-)25% to (+) 10% (-)25% to (+) 10%