Employer

APPROVED APPROVED EXCEPT AS NOTED:RESUBMISSION REQUIRED NOT APPROVED, MODIFY AND RESUBMIT FOR INFORMATION ONLY. NOTE: THE APPROVAL SHALL NOT RELIEVE THE CONTRACTOR FROM HIS RESPONSIBILITY FOR COMPLIANCE TO CONTRACT REQUIREMENTS, DRAWING,SPECIFICATIONS & DATA SHEETS

EMPLOYER

CONTRACTORS

CONSULTANT

PROJECT

62

SIEMENS

KEPZ Extension (132/12 kV GIS Substation) RELAY SETTING CALCULATIONS

Date:

26.06.2018

Worked by:

Seema Naseer

Checked by:

Fatima Izhar

Approved by:

Yousuf Mubarak

Approved by:

C

*Remarks: LED configuration for all protection relays shall be made at site. SIEMENS Energy Sector Projects/Engineering

Page 2 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS A. A.1

40 MVA, POWER TRANSFORMERS PROTECTION Differential Protection(For E06 Bay)

7UT612

SIEMENS

Page 5

Transformer Differential Relay B.

RESTRICTED EARTH FAULT PROTEECTION

B.1

HV REF Relay

7SJ8012

SIEMENS

Page 17

B.2

LV REF Relay

7SJ8012

SIEMENS

Page 20

7SJ8031

SIEMENS

Page 25

OC relay using standard inverse characteristics

7SJ8031

SIEMENS

Page 26

Outgoing Cable Feeder 12kV Circuit (400/5A)

7SJ8031

SIEMENS

Page 27

7SJ8031

SIEMENS

Page 28

7SJ8031

SIEMENS

Page 29

7SJ8031

SIEMENS

Page 30

7SJ8031

SIEMENS

Page 31

7SJ8011

SIEMENS

Page 32

7SJ8011

SIEMENS

Page 33

7SJ8031

SIEMENS

Page 38

Outgoing Aux Trafo Feeder 12kV Circuit (with newly proposed CT) 7SJ8031

SIEMENS

Page 39

7SJ8031

SIEMENS

Page 40

7SJ8031

SIEMENS

Page 41

C.

OVER CURRENT PROTECTION

C.1

Outgoing Aux Trafo Feeder 12kV Circuit OC relay using standard inverse characteristics

C.1A C.2

Outgoing Aux Trafo Feeder 12kV Circuit (with newly proposed CT)

OC relay using standard inverse characteristics C.2A

Outgoing Cable Feeder 12kV Circuit (800/5A) OC relay using standard inverse characteristics

C.3

Outgoing Capacitor Feeder 12kV Circuit (400/5A) OC relay using standard inverse characteristics

C.4

Outgoing Capacitor Feeder 12kV Circuit (800/5A) OC relay using standard inverse characteristics

C.5

40 MVA Transformer 12kV Incomer Circuit(Trafo. LV side) OC relay using standard inverse characteristics

C.6

40 MVA Transformer 132 kV Circuit (Trafo HV side) OC relay using standard inverse characteristics

C.7

13.3 MVA, Tertiary winding OC relay using standard inverse characteristics

D.

BACK UP EARTH FAULT PROTECTION

D.1

Outgoing Aux Trafo Feeder 12kV Circuit EF relay using standard inverse characteristics

D.1A

EF relay using standard inverse characteristics D.2

Outgoing Cable Feeder 12kV Circuit (400/5A) EF relay using standard inverse characteristics

D.2A

Outgoing Cable Feeder 12kV Circuit (800/5A) EF relay using standard inverse characteristics

*Remarks: LED configuration for all protection relays shall be made at site. SIEMENS Page 3 + Energy Sector Projects/Engineering

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.3

Outgoing Capacitor Feeder 12kV Circuit (400/5A)

7SJ8031

SIEMENS

Page 42

7SJ8031

SIEMENS

Page 43

7SJ8031

SIEMENS

Page 44

7SJ8031

SIEMENS

Page 45

7SJ8011

SIEMENS

Page 46

7SJ8011

SIEMENS

Page 47

7SJ8011

SIEMENS

Page 48

7SJ8011

SIEMENS

Page 49

7SJ8011

SIEMENS

Page 50

EF relay using standard inverse characteristics D.3A

Outgoing Capacitor Feeder 12kV Circuit (800/5A) EF relay using standard inverse characteristics

D.4

40 MVA Transformer 12kV Incomer Circuit(Trafo. LV Side) with NGR EF relay using standard inverse characteristics

D.4A

40 MVA Transformer 12kV Incomer Circuit(Trafo. LV Side) without NGR EF relay using standard inverse characteristics

D.5

40 MVA Transformer 12kV Circuit Neutral Protection (LV Side) with NGR EF protection using standard inverse characteristics

D.5A

40 MVA Transformer 12kV Circuit Neutral Protection (LV Side) without NGR EF protection using standard inverse characteristics

D.6

40 MVA Transformer 132 kV Circuit(Trafo HV Side) EF relay using standard inverse characteristics

D.7

13.3 MVA, Tertiary Winding TEF protection using standard inverse characteristics

D.8

40 MVA Transformer 132 kV Circuit Neutral Protection (HV Side) EF protection using standard inverse characteristics

D.9

40 MVA Transformer ,EF Relay for NGR

P14N

Shanghai Xinguang Page 51

EF protection using standard inverse characteristics E.

AVR RELAY

E.1

40MVA, PTR AVR RELAY

F.

CAPACITOR UNBALANCE PROTECTION

TAPCON

MR

Page 55

SIEMENS

Page 57

230 EXPERT

F.1 G.

Capacitor Bank Unbalance Protection Annexure

7SJ8031

Page 58

*Remarks: LED configuration for all protection relays shall be made at site. SIEMENS Page 4 + Energy Sector Projects/Engineering

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

Differential Protection

SIEMENS Energy Sector Projects/Engineering

Page 5 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

40 MVA Transformer Differential Protection Setting Calculation Data: I ). Relay type II ). Transformer Rating

=

7UT6121-5EB22-1AA0

=

40

MVA

III ). Voltage at maximum tap

Umax

=

151.80

kV

IV ). Voltage at minimum tap

Umin

=

112.20

kV

V ). Transformation Ratio

=

132 /12

VI ). Tap changing Range

=

+ 15 %

VII ).Vector Group

=

YNyn0(d11)

VIII) HV CT Ratio

=

200/1

A

=

2500/5

A

IX) LV CT Ratio

to

- 15 %

Calculations: A ). Rated Current B ). Differential Initial Setting

I - Diff >

C ). Differential Bias Slope Setting

SLOPE 1

D ). Differential Bias Slope Limit

SLOPE 2

E ). Differential Highest Setting

I - Diff >>

F ). Magnetising Inrush Restraint Level A

Load Current: As per 7UT612 manual , If a transformer winding is regulated, then the actual rated voltage of the winding is not used as UN for the stabilized side,but the voltage corresponding to the average current of the regulated range. The following applies: UN

=

2 x [(Umax x Umin) ÷ (Umax + Umin)]

(Refer 7UT manual page 21)

where Umax, Umin are the voltages at the limits of the regulated range. UHV

The voltage set on 132 kV side

= =

2 x [(151.8 x 112.2) 129.03

÷ (151.8

+112.2)]

kV

HV SIDE : Transformer Rated Current HV regulated side

=

40000

=

178.98172

=

0.895

÷

(√3 x 129.0)

=

178.9817

Corresponding rated current on secondary side of CT

SIEMENS Energy Sector Projects/Engineering

I N1

÷ 200/1

= 0.895

@ INObj

Page 6 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS LV SIDE : Transformer Rated Current LV unregulated side

=

40000

÷

(√3 × 12.0)

=

=

1924.5009

÷

2500 / 5 A

=

=

3.849

1924.501

Corresponding maximum full load current I N2

on secondary side of CT

B

Differential Initial Setting

3.849

@ INObj

I - DIFF >

Spill current calculation due to following Constant Errors: ●

Tap changer regulation

●

Magnetizing currents of CTs and Power transformer Transformer Rated Current at maximum tap position(1), +15%.

=

40000

÷

(√3 ×151.8 )

=

152.1

Corresponding maximum full load current at max. tap on secondary side of CT

= IN1(+15%)

→

÷ 200/1

=

0.761

@

IN1(+15%)

− INObj

Differential current in max. tap position

I Diff

=

Differential current in max. tap position

I Diff

=

Differential current at max. tap position

152.134

= 0.761 I NObj

0.85

(Refer 7UT manual page 34)

* I NObj - I NObj

0.85

=

I NObj

=

-0.150

I NObj

=

0.150

I NObj

=

40000

÷

=

205.829

0.850

-1

= 15.0%

Transformer Rated Current at minimum tap position(25) -15%.

(√3 ×112.2 )

=

205.829

Corresponding rated current at min tap on secondary side of CT IN1(-15%)

= I Diff

=

Differential current in min. tap position

I Diff

=

=

SIEMENS

IN1(-15%)

1.15

1.150 0.150

= 1.029 I NObj

− INObj =

1.15 *I NObj - I NObj

I NObj

=

Energy Sector Projects/Engineering

@

1.029

Differential current in min. tap position

÷ 200/1

1.15 *I NObj - I NObj (Refer 7UT manual page 34)

-1

I NObj

Page 7 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

→

Differential current at min. tap position

=

0.150

Thus tap changer regulation error is

=

15.0%

I NObj

CT magnetizing errors and mismatching of Cts has been considered as= 0.015 %

Maximum differential current

=

15.00%

+

0.02%

=

15.02%

=

20%

Considering safety margin based on variations of above factors due to variation in system condition and environment, the pick up value of differential current is to be selected as,

I - Diff >

(Available settings: 0.05 … 2.00 I/I no)

C

Differential Bias Slope Setting ○ Base Point 1 Considering the differential and restraining currents are equal at normal loading, therefore, by straight line equation; m = (y2 - y1) ÷ (x2 -x1) m= \

-1

tan = (m)

=

1

-

0

÷

1

-

0 =

1

45°

Since in the beginning, errors in Cts are unaccountable and differential / stabilizing currents are balance, therefore, base point of slope 1 is to be selected as, BASE POINT 1

=

0.00

(Available settings: 0.00 … 2.00 I/I no)

○ SLOPE 1 ●

As per manufacturer's guide line, the tripping characteristic is characterized by two slopes. Address 1241 A

SIEMENS Energy Sector Projects/Engineering

Slope 1 consider current proportional error which may result from

Page 8 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

e.g. ○

tap changer's regulation range of power transformer and

○

CT transformation manufacturing limitations.

These errors increases with increase in load, to find the suitable slope consider I diff = Therefore at full load, current I 1 = 1

and due to

20%

errors

20 % 0.8

I2=

Then according to stabilising current equation, I stab,

x

=

I1

I2

+

=

1

+

0.8

=

1.8 (Refer 7UT manual page 258)

If the slope selected is 0.1, then I diff,

y

= m.X+b =

I diff

( slope equation )

0.10 x 1.8

= 0.180

Though we have

20 %

differential current but relay shall give tripping at

18%

, therefore this value is not suitable. Now, the slope selected is 0.15 at full load \ I stab x, I diff,

y

=

+

I2

=

1

+

0.8

=

1.8

= m.X+b =

I diff

I1

( slope equation )

0.15 x 1.8

= 0.270

Therefore, from the above calculations we found that slope

0.150

is better

compensated for errors. But as per client's recommendation the slope setting is set 0.3 at full load. \ I stab x, I diff,

y

=

+

I2

=

1

+

0.8

= m.X+b =

I diff

I1

=

1.8 ( slope equation )

0.30 x 1.8

= 0.540

Thus Slope 1 setting

SLOPE 1

=

0.30

(Available settings: 0.10 … 0.50)

SIEMENS Energy Sector Projects/Engineering

Page 9 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

○ Base Point 2 This produces higher stabilization in the range of high currents which may lead to current transformer saturation. To consider base point for slope 2; For higher load currents 25% overloading is considered, therefore, Istab

=

I1

=

I2

+

1.25

+

1.25

=

(Refer 7UT manual page 258)

2.5

As the CT saturation criteria starts at this value, therefore, it is to be set at the value of

2.5 I/Ino

=

(Available settings: 0.00 … 10.00 I/I no)

○ SLOPE 2 ●

Address 1243 A

Slope 2 provides stabilization in differential scheme in case of higher

through fault currents resulted current transformer saturation. The stability of the protection can be influenced by these settings. To find the suitable slope consider the stabilization current, I stab

y

= m.X+b

For through fault current under heavy load, following satisfies Transformer 1:

Since

I1 =

If

÷

If

=

214247

÷

(√3×

112 )

=

1104.4 A

In

=

40000

÷

(√3×

132 )

=

175.0 A

1104.43

÷

175.0

In

=

=

6.313

Consider that degree of differential current at this point = 50% and fault is out side the zone, therefore, I diff(act),

y

=

I1

+

I2



I1

−

I2

I diff(act),

y

=

I1

+

I2



I1

−

I2

=

I diff(act),

y

=

-3.156

@

-3.2

Istab

=

I1

+

I2

=

6.31

=

9.469

+

3.16

(Refer 7UT manual page 258) 6.31

− 6.31 x 0.5

Now we set slope at 0.4 and check the suitability and veryfying the relation by; I diff(act) < I diff(set) I diff(set), I diff(set)

y

= m.X+b

=

0.40 x

9.469

at -

m

=

0.4

X

=

9.469

b

=

-1

1

= 2.788

SIEMENS Energy Sector Projects/Engineering

Page 10 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

But as per client's recommendation the slope setting is set at 0.7, I diff(set), y = m.X+b Now taken m = 0.7 = 0.70 x 9.469 -1.75 = 4.878 This I diff(set) value confirms the relation,

I diff(act) < I diff(set)

x

Differential Highest Setting

9.469

b=

-1.75

therefore the set value of SLOPE 2

(Available settings: 0.25 … 0.95)

D

=

=

0.70

I - DIFF >>

Rated current of transformer at normal tap.

=

178.98

=

18.67 %

A

Transformer Percentage impedance of transformer

= \ Fault MVA at this impedance

=

0.1867 40

÷

pu 0.187

= 214

MVA

Considering maximum fault MVA gives If

maximum through fault current

=

214

=

1102.46

A

Corresponding current at CT secondary

=

5.51

A

Through fault current with respect to I n

=

5.51

× 1000 ÷

÷

0.895

( √3 ×

=

112.2

6.160

)

I/In

It is set to be as I - Diff >> =

(Available settings: 0.5 … 35 I/I no)

SIEMENS Energy Sector Projects/Engineering

7.5

I/Ino

Page 11 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS ● ●

1226A

Trip time delay Idiff >

1236A

Trip time delay Idiff >>

In special cases it may be advantageous to delay the trip signal of the protection. But for this case we will not use this delay time, and relay will give tripping command as soon as it senses differential condition above threshold. Therefore Time delay is set zero.

E

Add-on stabilization

I - ADD ON STAB.

During an external fault which produces as high through flowing short circuit current causing current transformer saturation, a considerable differential current can be simulated, especially when the degree of saturation is different at the two measuring points. 7UT612 provides a saturation indicator which detects such phenomena and initiates add-on stabilization measures. The saturation indicator operates dynamically in the area which is designated with "add-on Stabilization". Current Transformer saturation during external faults is detected by a high initial stabilizing current which moves the operating point briefly into the "add-on stablization"area. In contrast, the operating point moves immediately along the fault characteristic when an internal fault occurs since the stabilization current will barely be higher than the differential current. The saturation indicator makes its decision within the first half period after fault inception. Transformer through fault current is calculated as; Transformer : since,

If

=

214247

÷

(√3×

112.2 )

=

1102.5 A

In

=

40000

÷

(√3×

132 )

=

174.95 A

(I f / I n) of I n

=

1102.4583

÷

174.954627 =

The Value is set as

6.3014 of I no

=

6.50

I/Ino

(Available settings: 2.00 … 15.00 I/I no)

SIEMENS Energy Sector Projects/Engineering

Page 12 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

F

2nd HARMONIC The Inrush current can amount to a multiple of the rated current and is characterized by a considerable 2nd harmonic content which is practically absent in the case of shortcircuit. Stabilization during inrush condition via 2nd harmonic content in differential current is also detected by relay which just initiates blocking of the tripping. \ Selected value =

15 %

( It is recommended by manufacturer which is sufficient in 90 % cases) (Available settings: 10 … 80%)

G

Cross blocking for 2nd Harmonic Since the inrush stabilization operates individually per phase, the protection is fully operative even when the transformer is switched on a single phase fault, whereby inrush currents may possibly be present in one of healthy phases. However, it is also possible to set the protection such that not only phase with inrush current exhibiting harmonic content in excess of the permissible value is stabilized but also the other phases of the differential stage I Diff> are blocked (so called "Cross block function). This cross-block can be limited to a selectable duration and can be set from 0 to 1000 AC period. Normally this function is set ineffective, however, in abnormal inrush condition this can be set to block in a defined ac period. According to the inrush current report of the transformer we suggest the setting of Cross block function Set at

=

25

Cycles

(Available settings: 2 … 1000Cycle; 0; 

H

nth Harmonic Steady-state over excitation of transformer is characterized by odd harmonic content. The 3rd or 5th Harmonic is suitable to detect over excitation as the third harmonic is offered eleminated in the transformer windings (e.g. In a delta connected winding group), The fifth harmonic is usually used to avoid trip during over excitation, since the trafo is being used as distribution transformer, therefore, nth Harmonic function is set (Available settings: 10 … 80 %

SIEMENS Energy Sector Projects/Engineering

= 30%

Page 13 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS I.

Transformer parameter settings: ○ Rated primary voltage side 1 As per 7UT612 manual section 2.1.2, If a transformer winding is regulated, then the actual rated voltage of the winding is not used as UN for the stabilized side,but the voltage corresponding to the average current of the regulated range. The following applies: UN

=

2 x [(Umax x Umin) ÷ (Umax + Umin)]

(Refer 7UT manual page 21)

where Umax, Umin are the voltages at the limits of the regulated range. The voltage set on 132 kV side

UHV

=

2x

=

129.03

[(151.8

x 112.2) ÷

(151.8

+112.2)]

=

129.0 kV

kV

\ the rated primary voltage

○ Rated Secondary voltage side 2 The rated voltage of transformer side 2 in kV (phase to phase) is set under this address. =

\ the rated primary voltage

12.0 kV

○ Rated apparent power of the transformer(side 1 & 2) The primary rated apparent power of transformer is set under this address. The power must always be entered as a primary value, even if the device is generally configured in secondary values. 40.00 MVA

=

The apparent of transformer is (Available settings: 0.20 to 5000.00 MVA)

○ Starpoint of transformer the starpoint of side 1 is

=

Solid grounded

the starpoint of side 2 is

=

Resistor grounded

As the starpoint of transformer`s side 2 is earthed through NGR.

SIEMENS Energy Sector Projects/Engineering

Page 14 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

J.

CTs parameter settings:

○ CT starpoint in direction of object side 1 In order to ensure the correct polarity for the differential currents, the CT starpoint in direction of protected object is set under this address. = (Towards object)

Selected setting

(Furhter to be confirmed at site) ○ CT rated primary current side 1 This parameter is set to the rated primary current of the CT. Selected setting

=

200

=

1A

○ CT rated secondary current side 1 This parameter is set to the rated secondary current of the CT. Selected setting

○ CT starpoint in direction of object side 2 In order to ensure the correct polarity for the differential currents, the CT starpoint in direction of protected object is set under this address. = (Towards object)

Selected setting

(Furhter to be confirmed at site) ○ CT rated primary current side 2 This parameter is set to the rated primary current of the CT. Selected setting

=

2500

=

5A

○ CT rated secondary current side 2 This parameter is set to the rated secondary current of the CT. Selected setting

SIEMENS

Energy Sector Projects/Engineering

Page 15 +

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS Setting Parameters General Data: Address

Function

Value

0270

Rated Frequency

50 Hz

0271

Rated Sequence

L1,L2,L3

0312

Rated Apparent Power of Trafo side.1

40MVA

0322

Rated Apparent Power of Trafo side.2

40MVA

0311

Rated Primary Voltage side.1

129kV

0321

Rated Primary Voltage side.2

12kV

0313

Starpoint of side.1

Solid Grounded

0323

Starpoint of side.2

Resistor Grounded

0314

Trafo Winding Connection Side.1

Y(Wye)

0324

Trafo Winding Connection Side.2

Y(Wye)

0325

Vector Group Numeral of Side.2

0

0511

CT Starpoint in direction of object side.1

Towards Object (Further to be confirmed at site)

0512

CT rated Primary current Side.1

200A

0513

CT rated Seconadry current Side.1

1A

0521

CT Starpoint in direction of object side.2

Towards Object (Further to be confirmed at site)

0522

CT rated Primary current Side.2

2500A

0523

CT rated Seconadry current Side.2

5A

Differential Protection Address

Function

Value

Range

1201

Differential Protection

ON

On,OFF,BLK

1206

Inrush with 2. Harmonic Restraint

ON

On,OFF

1207

n-th Harmonic Restraint

5th Harm

3.Harm,5.Harm,OFF

1221

Pickup Value of Differential Curr.

0.2 I/Ino

0.05 to 2.00

1226A

T I-DIFF> Time Delay

0.00 s

0.00 to 60.00

1231

Pickup Value of High Set Trip I-DIFF>>

7.5 I/Ino

0.5 to 35.0

1236A

T I-DIFF>> Time Delay

0.00 s

0.00 to 60.0

1241A

Slope 1 of Tripping Characteristic

0.30

0.1 to 0.5

1242A

Base Point for Slope 1 of Charac.

0.0 I/Ino

0.0 to 2.0

1243A

Slope 2 of Tripping Characteristic

0.70

0.25 to 0.95

1244A

Base Point for Slope 2 of Charac.

2.5 I/Ino

0.0 to 10.0

1256A

Pickup for Add-on Stabilization

6.5 I/Ino

2.00 to 15.0

1257A

Duration of Add-on Stabilization

15 cycles

2 to 250

1261

2nd Harmonic Content in I-DIFF

15 %

10 to 80

1262A

Time for Cross-blocking 2nd Harm.

25 cycles

2 to 1000

1271

n.HARMONIC

30 %

10 to 80

1272A

Time for Cross-blocking n. Harm.

0 cycles

2 to 1000

SIEMENS Energy Sector Projects/Engineering

Page 16 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

HV Restricted Earth Fault Protection

SIEMENS Energy Sector Projects/Engineering

Page 17 +

### EM-TS PROJECTS /A5175/Relay Settings

SIEMENS Transformer HV Restricted Earth Fault Protection Relay Type: 7SJ8012-5EB20-1FA0 HV Bushing CT 200/1A

CT Ratio: Class of Accuracy:

5P20

Burden:

30

VA

CT Resistance:

Rct = 0.7

Knee Point Voltage:

VK = 540

CT primary current:

200

Ω V

A

Power Transformer Data: Power Rating =

40

MVA

Percentage Impedance =

18.67

%

Rated HV Voltage = U N =

112.2

kV

Trafo. Rated Current

(at Maximum tap:112.2kV)

I TFL = Power Rating /(3 x Voltage) 6 = 40 x 10 / (3 x 112000)

=

3-phase primary fault current

205.83 A

I F = Power Rating /(3 x Voltage x Percentage impedance) 6 = 40 x 10 / (3 x 112200 x 18.67/100)

(Calculated at the highest tap:

112.2 kV)

= 1102.46 A

Maximum primary through fault current of trafo

IF =

1500 A

(20 times the rated current) 7SJ8012 HV RESTRICTED EARTH FAULT SETTINGS 1 Maximum value of primary fault current for Internal Fault

IF

=

1500.00

A

2 Maximum value of primary through fault current for which prot must remain stable

I FM

=

1102.46

A

3 Trafo full load current

I TFL

=

205.83

A

4 Turns ratio of CT core

N

=

200

5 CT Secondary current

I sn

=

1

6 Rated symmetrical short-circuit current factor

Kssc

=

20

7 Rated CT Burden

Rb

=

30

Ω

8 CT knee point voltage

VK

=

540.00

V

9 CT Secondary Winding Resistance

RCT

=

0.70

Ohms

10 Lead resistance between furthest current transformer and relay

RL

=

0.40

Ohms

=

6

Ohms

0.02

A

0.090

A

A

terminals VA/I R2

11 Relay Impedance

RR

12 CT core magnetizing current (secondary) at relay setting voltage (Calculated)

IE

=

13 Relay Operating Current

IR

=

(Relay setting current range)

SIEMENS Energy Sector Projects/Engineering

(0.001….1.4)

Page 18 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

14 Number of CT cores in circulating current differential circuit

n

15 Minimum Setting Voltage (Calculated)

Vs

I FM x (RCT + 2 x RL) / N

=

4

=

8.27

V

=

50

V

=

34.0

A

(Refer Siemens Reyroll manual page 9) 16 Relay setting voltage

VR

17 Primary current required for pick-up of protection (sensitivity)

IP

N x (I R + n x I E + I m)

(Refer Siemens Reyroll manual page 9) Primary current required for pick-up of protection as percentage

=

16.52%

=

9227

V

6126.08

V

of I TFL

of trafo full load current VF

18 The theoretical voltage which would be produced across the

I FM x (RL + RCT + Rs+ RR) / N

(Refer Siemens 7SJ8 High imp test page:15) relay circuit under internal fault condition. 19 Peak voltage across relay circuit under maximum internal fault

2√(2VK (VF - VK)

VRMAX

=

(Refer Siemens 7VH6 manual page:A-5)

conditions.

VRMAX > 2KV

20 External Metrosil required

=

Yes

=

0.0000

(Refer 7VH60 manual page A-5) Im

21 Metrosil Current (calculated)

0.52 x(Vs xѴ2 / C)^1/β

A

(Refer Metrosil manual page 1) 22 Constant(given value)

C

=

405

23 Constant(given value)

β

=

0.250

VR / IR

=

555.55 Ohms

RS

24 Value of stabilizing resistor(calculated)

(Vk>2VS and Vk<4VS) (Refer Siemens 7SJ8 High imp test page:11) 25 Knee point Voltage must be greater than twice

VK > 2VR

=

Yes

(Refer Siemens 7SJ8 High imp test page:11) the relay setting voltage 26 Continuos Power rating of Stabilizing Resistor

(I R2 X Rs)

=

14

Watt

( Vk3 x Rs x I fm )1/4 x 1.3

=

1426

Watt

1220

Watt

Pstab,cont

27 RMS Voltage Developed across stabilizing resistor

Vrms

Vrms

(Refer Siemens 7SJ8 High imp test page:14) Pstab,0.5s

28 Short time Power rating of Stabilizing Resistor

(Vrms2/Rs)

=

(Refer Siemens 7SJ8 High imp test page:14)

Setting Parameters General Data Adress

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

200A

0205

CT Rated Secondary Current

1A

0217

IE-CT Rated Primary Current

200A

0218

IE-CT Rated Secondary Current

1A

HV REF Protection Adress

Function

Value

Range

3117

50 1 Ph-1 Pickup

0.090

0.001 to 1.600 A: infinity

Stabilising Resistor (Variable)

Rs

= 555. 55

Primary Operating Current,

IP

= 34.0

Metrosil Require

SIEMENS Energy Sector Projects/Engineering

W (0 - 2000 W Variable

= Yes

Page 19 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

LV Restricted Earth Fault Protection

SIEMENS Energy Sector Projects/Engineering

Page 20 + ### EM-TS PROJECTS /A5175/Relay Settings

SIEMENS Transformer LV Restricted Earth Fault Protection Relay Type: 7SJ8012-5EB20-1FA0 LV Bushing CT 2500/5A

CT Ratio: Class of Accuracy:

5P20

Burden:

30

VA

CT Resistance:

Rct = 0.9

Knee Point Voltage:

VK = 120

CT primary current:

2500

Ω V

A

Power Transformer Data: Power Rating = Percentage Impedance =

40

MVA

18.67

%

Rated LV Voltage = UN =

12

kV

(at Maximum tap:112.2kV)

Trafo. Rated Current

I TFL = Power Rating /(3 x Voltage) 6 = 40 x 10 / (3 x 12000)

=

3-phase primary fault current

1924.50 A

I FM = Power Rating /(3 x Voltage x Percentage impedance) 6 = 40 x 10 / (3 x 12000 x 18.67/100)

Maximum primary fault current

=

10309.28 A

IF =

1500 A

(Calculated at LV Voltage:

12 kV)

(equal to NGR ratings) 7SJ8012 LV RESTRICTED EARTH FAULT SETTINGS 1 Maximum value of primary fault current for Internal Fault

IF

=

1500

A

2 Maximum value of primary through fault current for which prot must remain stable

I FM

=

10307.99

A

3 Trafo full load current

I TFL

=

1924.50

A

4 Turns ratio of CT core

N

=

500

5 CT Secondary current

I sn

=

5

6 Rated symmetrical short-circuit current factor

Kssc

=

20

7 Rated CT Burden

Rb

=

1.2

Ω

8 CT knee point voltage

VK

=

120.00

V

9 CT Secondary Winding Resistance

RCT

=

0.90

Ohms

10 Lead resistance between furthest current transformer and relay

RL

=

0.40

Ohms

=

0.83

Ohms

0.021

A

0.600

A

2500/5

A

terminals VA/I R2

11 Relay Impedance

RR

12 CT core magnetizing current (secondary) at relay setting voltage (Calculated)

IE

=

13 Relay Operating Current

IR

=

(Relay setting current range)

SIEMENS Energy Sector Projects/Engineering

(0.001….1.4)

Page 21 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

14 Number of CT cores in circulating current differential circuit

n

15 Minimum Setting Voltage (Calculated)

Vs

I FM x (RCT + 2 x RL) / N

=

4

=

35.05

V

=

50

V

=

342.0

A

(Refer Siemens 7VH6 manual page:A-4) VR

16 Relay setting voltage

IP

17 Primary current required for pick-up of protection (sensitivity)

N x (I R + n x I E + I m)

(Refer Siemens 7SJ8 High imp test page:12) Primary current required for pick-up of protection as percentage

=

17.77%

=

1762

V

1255.51

V

of I TFL

of trafo full load current VF

18 The theoretical voltage which would be produced across the

I FM x (RL + RCT + Rs+ RR) / N

(Refer Siemens 7SJ8 High imp test page:15) relay circuit under internal fault condition. 19 Peak voltage across relay circuit under maximum internal fault

2√(2VK (VF - VK)

VRMAX

=

(Refer Siemens 7VH6 manual page:A-5)

conditions.

VRMAX > 2KV

20 External Metrosil required

=

NO

(Refer Siemens 7VH6 manual page:A-5) Im

21 Metrosil Current (calculated)

0.52 x(Vs xѴ2 / C)^1/β

=

0.00004

A

(Refer Metrosil manual page 1) 22 Constant(given value)

C

=

540

23 Constant(given value)

β

=

0.250

VR / IR

=

83

RS

24 Value of stabilizing resistor(calculated)

Ohms

(Vk>2VS and Vk<4VS) (Refer Siemens 7SJ8 High imp test page:11) 25 Knee point Voltage must be greater than twice

VK > 2VR

=

Yes

(Refer Siemens 7SJ8 High imp test page:11) the relay setting voltage 26 Continuos Power rating of Stabilizing Resistor

(I R2 X Rs)

=

30

Watt

( Vk3 x Rs x I fm )1/4 x 1.3

=

303

Watt

1105

Watt

Pstab,cont

27 RMS Voltage Developed across stabilizing resistor

Vrms

Vrms

(Refer Siemens 7SJ8 High imp test page:14) Pstab,0.5s

28 Short time Power rating of Stabilizing Resistor

(Vrms2/Rs)

=

(Refer Siemens 7SJ8 High imp test page:14)

Setting Parameters General Data Adress

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

2500A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Primary Current

2500A

0218

IE-CT Rated Secondary Current

5A

LV REF Protection Adress

Function

Value

Range

3117

50 1 Ph-1 Pickup

0.600

0.005 to 8.000 A: infinity

Stabilising Resistor (Variable)

Rs

= 83

Primary Operating Current,

IP

= 342

Metrosil Require

SIEMENS Energy Sector Projects/Engineering

W (0 - 150 W Variable

= NO

Page 22 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

BACKUP OVER CURRENT PROTECTION

SIEMENS Energy Sector Projects/Engineering

Page 23 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.

OVER CURRENT PROTECTION

C.1

Outgoing Aux Trafo Feeder 12kV Circuit OC relay using standard inverse characteristics

C.1A

Siemens

7SJ8031

Siemens

7SJ8031

Siemens

7SJ8031

Siemens

Outgoing Capacitor Feeder 12kV Circuit(800/5A) OC relay using standard inverse characteristics

C.5

7SJ8031

Outgoing Capacitor Feeder 12kV Circuit(400/5A) OC relay using standard inverse characteristics

C.4

Siemens

Outgoing Cable Feeder 12kV Circuit (800/5A) OC relay using standard inverse characteristics

C.3

7SJ8031

Outgoing Cable Feeder 12kV Circuit (400/5A) OC relay using standard inverse characteristics

C.2A

40 MVA Transformer 12kV Incomer Circuit(Trafo. LV side) 7SJ8031 OC relay using standard inverse characteristics

C.6

Siemens

40 MVA Transformer 132 kV Circuit (Trafo HV side) OC relay using standard inverse characteristics

C.7

Siemens

Outgoing Aux Trafo Feeder 12kV Circuit (with newly proposed CT) OC relay using standard inverse characteristics

C.2

7SJ8031

7SJ8011

Siemens

7SJ8011

Siemens

13.3 MVA Tertiary winding OC relay using standard inverse characteristics

SIEMENS Energy Sector Projects/Engineering

Page 24 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.1

500 KVA Aux Transformer 12kV side Overcurrent Protection

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

800 /

400 /

5A

Plug Setting: Considering 1.2 times overloading, the overcurrent plug setting of protected object should be

120 % of rated current. = 500kVA x 1.2 ÷

(√3

x 12 kV)

= 28.87 A = 28.87 A

Corresponding secondary current

÷ 400

÷5

= 0.36 A

≈ 7.2% x In

= 0.36 A

pickup setting

= 0.5 to 20 A (steps 0.01) Recommneded Relay settings

= 8.0% x In

pickup setting

≈ 0.40 A ≈ 0.50 A

Hence selected pickup setting

(Note:Due to limitation of relay range ,we propose to select Pick up value 0.5 instead of 0.4) B.

Time Multiplier Setting: Fault Current contributed by

= 500kVA x 1 ÷

(√3 x 12 kV

transformer

= 522.96 A

Multiples of Fault Current

=

523.0

x 0.046)

÷( 400

/5

x 0.50)

= 13.07 A = 0.14

As per IEC Normal Inverse characteristic

÷ [(13.1)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.654 sec.

Operating time

= 2.65 sec.

at TMS = 1

Operating time for Auxiliary Trafo 12kV side

= 0.200

Since, 2.65 x TMS

= 0.200 sec. TMS = 0.075

Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time C.

= 2.650

x 0.080

0.080 0.212 sec.

Settings recommended :

General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

400A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

400A

0218

IE-CT Rated Secondary Current

5A

OverCurrent Protection Address

Function

Value

1207

51 Pickup

1.25A

0.50 to 20A

1208

51 Time Dial

0.080

0.05 to 3.2 sec

1211

51 IEC Curve SI** 1202 50-2 Pickup 15A** 1203 0 sec 50-2 Delay ** Note: Values has been modified as per site (GSM/GSP) recommendation. SIEMENS Energy Sector Projects/Engineering

Range

Norm,Very,Ext,long 5.0A to 75A 0 to 60 sec

Page 25 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.1A

500 KVA Aux Transformer 12kV side Overcurrent Protection Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

100 /

50 /

5A

(Note:Due to limitation of relay range ,we propose 100/5A ratio. Currently both settings have been (provided. However, 800/400/5A CT settings will be removed after confirmation) A.

Plug Setting: Considering 1.2 times overloading, the overcurrent plug setting of protected object should be

120 % of rated current. = 500kVA x 1.2 ÷

(√3

x 12 kV)

= 28.87 A = 28.87 A

Corresponding secondary current

÷ 100

÷5

= 1.44 A

≈ 28.9% x In

= 1.44 A

pickup setting

= 0.5 to 20 A (steps 0.01) Recommneded Relay settings

= 29.0% x In

pickup setting

≈ 1.45 A ≈ 1.45 A

Hence selected pickup setting B.

Time Multiplier Setting: Fault Current contributed by

= 500kVA x 1 ÷

(√3 x 12 kV

transformer

= 522.96 A

Multiples of Fault Current

=

523.0

x 0.046)

÷( 100

/5

x 1.45)

= 18.03 A = 0.14

As per IEC Normal Inverse characteristic

÷ [(18.0)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.351 sec.

Operating time

= 2.35 sec.

at TMS = 1

Operating time for Auxiliary Trafo 12kV side

= 0.200

Since, 2.35 x TMS

= 0.200 sec. TMS = 0.085

Available setting

= 0.05 to 3.2s (steps 0.01s)

≈ ≈

Hence the selected TMS Operating time C.

= 2.350

x 0.090

0.090 0.212 sec.

Settings recommended :

General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

100A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

100A

0218

IE-CT Rated Secondary Current

5A

OverCurrent Protection Address

Function

Value

1207

51 Pickup

1.45A

0.50 to 20A

1208

51 Time Dial

0.090

0.05 to 3.2 sec

NI

Norm,Very,Ext,long

28.7A** 0 sec

5.0A to 75A 0 to 60 sec

1211

51 IEC Curve 1217 50-3 Pickup 1218 50-3 Delay **1.1 x (Fault current/ CT ratio) = (522.9/100/5)*1.1=28.7 SIEMENS Energy Sector Projects/Engineering

Range

Page 26 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.2

12 kV Outgoing Feeder Overcurrent Protection (Settings at CT ratio 400/5 A)

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

800 /

400 /

Plug Setting: Considering max. current through the circuit

= 400 A

Feeder overloading considered as

= 400 A

Corresponding secondary current

= 400.0 A

5A

x 1.0

= 400 A ÷ 400

÷5

= 5.00 A

≈ 100.0% x In

= 5.00 A

Hence selected pickup setting

= 0.5 to 20 A (steps 0.01)

B.

Recommneded Relay settings

= 100.0% x In

Hence selected pickup setting

= 5.00 A

Time Multiplier Setting: Fault Current contributed by

=

40 MVA x 1 ÷

(√3 x 12 kV

transformer

= 10307.99 A

Multiples of Fault Current (I/I P)

= 10308

x 0.187)

÷( 400

/5

x 5.00)

= 25.77 A As per trip time characteristics according to IEC, tripping times do not decrease above I/I P > 20. = 0.14

\ As per IEC Normal Inverse characteristic

÷ [(20.00)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec.

at TMS = 1

= 0.200

Operating time for Out Going Feeder 12kV side For selectivity the tripping time choosen Since, 2.27 x TMS

= 0.200 sec. TMS = 0.088

Available setting

= 0.05 to 3.2s (steps 0.01s)

≈ ≈

Hence the selected TMS Operating time

C.

= 2.270

x 0.090

0.090 0.204 sec.

Settings recommended :

General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

400A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

400A

0218

IE-CT Rated Secondary Current

5A

OverCurrent Protection Address

Function

Value

Range

1207

51 Pickup

5.00A

0.50 to 20A

1208

51 Time Dial

0.090

0.05 to 3.2 sec

1211

51 IEC Curve

NI

Norm,Very,Ext,long

1217

50-3 Pickup 50-3 Delay

30A** 0 sec

5.0A to 75A

1218

0 to 60 sec

**Note: As per KE Practice, since fault current is 2400A at primary side, therefore high set will be considered (fault current/CT ratio)=(2400/400/5)=30A at secondary side. SIEMENS Energy Sector Projects/Engineering

Page 27 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.2A

12 kV Outgoing Feeder Overcurrent Protection (Settings at CT ratio 800/5 A)

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

800 /

400 /

5A

Plug Setting: Considering max. current through the circuit

= 800 A

Feeder overloading considered as

= 800 A

Corresponding secondary current

= 800.0 A

x 1.0

= 800 A ÷ 800

÷5

= 5.00 A

≈ 100.0% x In

= 5.00 A

Hence selected pickup setting

= 0.5 to 20 A (steps 0.01)

B.

Recommneded Relay settings

= 100.0% x In

Hence selected pickup setting

= 5.00 A

Time Multiplier Setting: Fault Current contributed by

=

40 MVA x 1 ÷

(√3 x 12 kV x 0.187)

transformer

= 10307.99 A

Multiples of Fault Current (I/I P)

= 10308

÷( 800

/5

x 5.00)

= 12.88 A = 0.14

\ As per IEC Normal Inverse characteristic

÷ [(12.88)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.669 sec.

Operating time

= 2.67 sec.

at TMS = 1

= 0.200

Operating time for Out Going Feeder 12kV side For selectivity the tripping time choosen Since, 2.67 x TMS

= 0.200 sec. TMS = 0.075

Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time C.

= 2.670

x 0.080

0.080 0.214 sec.

Settings recommended :

General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

800A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

800A

0218

IE-CT Rated Secondary Current

5A

OverCurrent Protection Address

Function

Value

1207

51 Pickup

5.00A

0.50 to 20A

1208

51 Time Dial

0.080

0.05 to 3.2 sec

1211

51 IEC Curve

SI**

Norm,Very,Ext,long

15A** 0.1 sec

5.0A to 75A 0 to 60 sec

1202 1218 ** Note:

50-2 Pickup 50-2 Delay

Range

Values has been modified as per site (GSM/GSP) recommendation. SIEMENS Energy Sector Projects/Engineering

Page 28 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.3

4 MVA, 12 kV Capacitor Feeder Overcurrent Protection

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

800 /

400 /

5A

=

4MVA

x 1.0 ÷

=

192.45 A

=

192.45 A

=

2.41 A

=

2.41 A

=

0.5 to 20 A(steps 0.01)

Recommneded Relay settings

=

49.0% x In

Hence selected pickup setting

=

2.45 A

Plug Setting: Feeder overloading considered as Corresponding secondary current Hence selected pickup setting

B.

Time Multiplier Setting: Fault Current contributed by

=

40 MVA

x1 ÷

÷ 400

÷5

≈ 48.1% x In

(√3 x 12 kV

x 0.187)

10307.99 A

transformer

=

Multiples of Fault Current

=

10308.0

=

52.59 A

=

0.14

As per IEC Normal Inverse characteristic

(√3 x 12 kV)

÷( 400 ÷ [(20.0)

/5 0.02

x 2.45)

-1]

(Refer 7SJ80 manual page 384) =

2.267 sec.

=

2.27 sec.

Operating time for Capacitor Feeder 12kV side

=

0.200

Since, 2.27 x TMS

=

0.200 sec.

=

0.088

Available setting

=

0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

0.090

Operating time

TMS

Operating time C.

= 2.270

x 0.090

at TMS = 1

0.204 sec.

Settings recommended :

General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

400A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

400A

0218

IE-CT Rated Secondary Current

5A

OverCurrent Protection Address

Function

1207

51 Pickup

2.5A**

0.50 to 20A

1208

51 Time Dial

0.080**

0.05 to 3.2 sec

1211

51 IEC Curve

SI**

Norm,Very,Ext,long

1202

50-2 Pickup 50-2 Delay

15A** 0 sec

5.0A to 75A 0 to 60 sec

1203

Value

Range

** Note: Values has been modified as per site (GSM/GSP) recommendation. SIEMENS Page 29 + Energy Sector Projects/Engineering

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.4

4 MVA, 12 kV Capacitor Feeder Overcurrent Protection

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

800 /

Plug Setting: Feeder overloading considered as

=

5A

4MVA x 1.0 ÷

(√3 x 12 kV)

=

192.45 A

=

192.45 A

=

1.20 A

=

1.20 A

=

0.5 to 20 A(steps 0.01)

Recommneded Relay settings

=

25.0% x In

Hence selected pickup setting

=

1.25 A

Corresponding secondary current Hence selected pickup setting

B.

400 /

Time Multiplier Setting: Fault Current contributed by

=

40 MVA

x1 ÷

÷5

≈ 24.1% x In

(√3 x 12 kV

x 0.187)

10307.99 A

transformer

=

Multiples of Fault Current

=

10308.0

=

51.54 A

=

0.14

As per IEC Normal Inverse characteristic

÷ 800

÷( 800 ÷ [(20.0)

/5 0.02

x 1.25)

-1]

(Refer 7SJ80 manual page 384) =

2.267 sec.

=

2.27 sec.

Operating time for Capacitor Feeder 12kV side

=

0.200

Since, 2.27 x TMS

=

0.200 sec.

=

0.088

Available setting

=

0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

0.090

Operating time

TMS

Operating time

= 2.270

x 0.090

at TMS = 1

0.204 sec.

C. Settings recommended : General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

800A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

800A

0218

IE-CT Rated Secondary Current

5A

OverCurrent Protection Address

Function

Value

1207

51 Pickup

1.25A

0.50 to 20A

1208

51 Time Dial

0.090

0.05 to 3.2 sec

1211

51 IEC Curve

NI

Norm,Very,Ext,long

1217

50-3 Pickup 50-3 Delay

20.0A 0 sec

5.0A to 75A 0 to 60 sec

1218

**1.1 x (Fault current/ CT ratio) = 1.1 x (10459.24/800/5) = SIEMENS Energy Sector Projects/Engineering

Range

71.9A

Page 30 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.5

40 MVA Transformer, 12 kV Incomer Overcurrent Protection

A.

Relay Type:

= 7SJ8031-5EB00-1FB0

CT Ratio

=

2500 /

5A

Plug Setting: Considering 1.2 times overloading, the overcurrent plug setting of protected object should be

120

% of rated current.

Transformer LV winding rated current

40 MVA x 1.2 ÷

=

(√3 x 12 kV)

= 2309.40 A = 2309.4 A

Corresponding secondary current

÷ 2500

÷5

= 4.62 A

≈ 92.4% x In

= 4.62 A

Hence selected pickup setting

= 0.5 to 20 A(steps 0.01)

B.

Recommneded Relay settings

= 93.0% x In

Hence selected pickup setting

= 4.65 A

Time Multiplier Setting: Fault Current contributed by

=

40 MVA x 1 ÷

(√3 x 12 kV

transformer

= 10307.99 A

Multiples of Fault Current

=

x 0.187)

10308.0 ÷( 2500

/5

x 4.65)

= 4.43354 As per IEC Normal Inverse characteristic

0.14

=

÷ [(4.43)

0.02

-1]

(Refer 7SJ80 manual page 384) = 4.631 sec.

Operating time

= 4.63 sec. = 0.900

Operating time for transformer 12kV side

at TMS = 1 (as per Client)

= 0.900 Since, 4.63 x TMS

= 0.900 sec. TMS = 0.194

Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time

= 4.630

x 0.200

0.200 0.926 sec.

C. Settings recommended : General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

2500A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

2500A

0218

IE-CT Rated Secondary Current

5A

OverCurrent Protection Address

Function

Value

Range

1207

51 Pickup

4.23A**

0.50 to 20A

1208

51 Time Dial

0.2

0.05 to 3.2 sec

1211

51 IEC Curve

SI**

Norm,Very,Ext,long

20.62A** 0.4 sec

5.0A to 75A 0 to 60 sec

1202 1203 ** Note:

50-2 Pickup 50-2 Delay

Values has been modified as per site (GSM/GSP) recommendation. SIEMENS Page 31 + Energy Sector Projects/Engineering

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.6

40 MVA Transformer, 132 kV Trafo (HV side)Overcurrent Protection

A.

Relay Type:

= 7SJ8031-5EB00-1FB0

CT Ratio

=

200 /

1A

Plug Setting: Considering 1.2 times overloading, the overcurrent plug setting of protected object should be

120 % of rated current.

Transformer HV winding rated current

40 MVA

=

x 1.2 ÷

(√3 x 112 kV)

= 247.44 A Corresponding secondary current

= 247.44 A

÷ 200

÷1

Hence selected pickup setting

= 1.24 A

≈ 123.7% x In

= 0.1 to 4 A(steps 0.01)

B.

Recommneded Relay settings

= 124.0% x In

Hence selected pickup setting

≈ 1.24 A

Time Multiplier Setting: Fault Current contributed by

=

40 MVA x 1 ÷

(√3

a transformer at 132kV side

= 1104.43 A

Multiples of Fault Current

=

1104.43

=

4.45 A

=

0.14

As per IEC Normal Inverse characteristic

x 112 kV

x 0.187)

÷( 200

/1

÷ [(4.45)

0.02

x 1.24)

-1]

(Refer 7SJ80 manual page 384) = 4.617 sec.

Operating time

= 4.62 sec. = 1.200

Operating time for transformer 132kV side Since, 4.62 x TMS

at TMS = 1 (as per Client)

= 1.200 sec. TMS = 0.2597

Available settings

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time C.

= 4.620

x 0.260

0.260 1.201 sec.

Settings recommended :

General Data Address

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

200A

0205

CT Rated Secondary Current

1A

0217

IE-CT Rated Secondary Current

200A

0218

IE-CT Rated Secondary Current

1A

OverCurrent Protection Address

Function

Value

Range

1207

51 Pickup

1.24A

0.10 to 4A

1208

51 Time Dial

0.260

0.05 to 3.2 sec

1211

51 IEC Curve

NI

Norm,Very,Ext,long

1217 1218

50-3 Pickup 50-3 Delay

6.16A** 0 sec

5.0A to 75A 0 to 60 sec

**1.1 x (Fault current/ CT ratio) = 1.1 x (1120/200/1) =6.16 SIEMENS Page 32 + Energy Sector Projects/Engineering

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS C.7

13.3 MVA Tertiary Winding Overcurrent Protection

A.

Relay Type:

= 7SJ8011-5EB20-1FA0

CT Ratio

=

Plug Setting: Transformer tertiary winding rated current

=

500 /

5A

13 MVA x 1.0 ÷

(√3 x 12 kV)

= 639.90 A = 640 / 1.732

=

Corresponding secondary current

= 370

÷ 500

Hence selected pickup setting

= 3.70 A

≈

1.00 A

370 X

÷5

74.0% x In

= 0.5 to 20 A(steps 0.01)

B.

Recommneded Relay settings

= 74.0% x In

Hence selected pickup setting

≈ 3.70 A

Time Multiplier Setting: Fault Current

= 5.1KA (Given as per manufacturer)

Multiples of Fault Current

=

5100.00

=

13.78 A

=

0.14

As per IEC Normal Inverse characteristic

÷( 500 ÷ [(13.78)

/5 0.02

x 3.70)

-1]

(Refer 7SJ80 manual page 384) = 2.599 sec.

Operating time

= 2.60 sec.

at TMS = 1

= 0.500

for selectivity the tripping time chosen Since, 2.60 x TMS

= 0.500 sec. TMS = 0.1923

Available settings

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time C.

= 2.600

x 0.200

0.200 0.520 sec.

Settings recommended :

General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

500A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

500A

0218

IE-CT Rated Secondary Current

5A

OverCurrent Protection Address

Function

Value

1207

51 Pickup

3.7A

0.50 to 20A

1208

51 Time Dial

0.2

0.05 to 3.2 sec

1211

51 IEC Curve

NI

Norm,Very,Ext,long

56.1A** 0 sec**

5.0A to 75A 0 to 60 sec

1217 1218 ** Note:

50-3 Pickup 50-3 Delay

Range

1.1 x (Fault current/ CT ratio) = 1.1 x (5100/500/5) = 56.1A Values has been modified as per site (GSM/GSP) recommendation. SIEMENS Page 33 + Energy Sector Projects/Engineering

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS Results Summary

Operating Time

PMS

TMS

0.2 sec.

2.5A**

0.080

C.1A 500 KVA Aux Transformer 12kV Circuit(with newly proposed CT) 0.2 sec. OC relay using standard inverse characteristics

1.45 A

0.090

0.2 sec.

5.00A

0.090

0.2 sec.

5.00A

0.080

0.2 sec.

4.85A

0.090

0.2sec.

2.45A

0.090

0.9 sec.

4.23A**

0.2

1.2 sec.

1.24A

0.270

0.5 sec.

3.7A

0.2

C.1

500 KVA Aux Transformer 12kV Circuit OC relay using standard inverse characteristics

C.2

Outgoing Cable Feeder 12kV Circuit (400/5A) OC relay using standard inverse characteristics

C.2A Outgoing Cable Feeder 12kV Circuit (800/5A) OC relay using standard inverse characteristics C.3

Outgoing Capacitor Feeder 12kV Circuit(400/5A) OC relay using standard inverse characteristics

C.4

Outgoing Capacitor Feeder 12kV Circuit(800/5A) OC relay using standard inverse characteristics

C.5

40 MVA Transformer 12kV Incomer Circuit(Trafo. LV side) OC relay using standard inverse characteristics

C.6

40 MVA Transformer 132 kV Circuit (Trafo HV side) OC relay using standard inverse characteristics

C.7

13.3 MVA Tertiary Winding Overcurrent Protection OC relay using standard inverse characteristics

SIEMENS Energy Sector Projects/Engineering

Page 34 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

EARTH FAULT PROTECTION

SIEMENS Energy Sector Projects/Engineering

Page 35 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.

BACK UP EARTH FAULT PROTECTION

D.1

Outgoing Aux Trafo Feeder 12kV Circuit EF relay using standard inverse characteristics

D.1A

7SJ8031

Siemens

7SJ8031

Siemens

7SJ8031

Siemens

7SJ8011

Siemens

7SJ8011

Siemens

7SJ8011

Siemens

7SJ8011

Siemens

40 MVA Transformer 132 kV Circuit(Trafo HV Side) EF relay using standard inverse characteristics

D.7

Siemens

40 MVA Transformer 12kV Circuit Neutral Protection Witout NGR (LV Side) EF protection using standard inverse characteristics

D.6

7SJ8031

40 MVA Transformer 12kV Circuit Neutral Protection with NGR (LV Side) EF protection using standard inverse characteristics

D.5A

Siemens

40 MVA Transformer 12kV Incomer Circuit(Trafo. LV Side) without NGR EF relay using standard inverse characteristics

D.5

7SJ8031

40 MVA Transformer 12kV Incomer Circuit(Trafo. LV Side) with NGR EF relay using standard inverse characteristics

D.4A

Siemens

Outgoing Capacitor Feeder 12kV Circuit(800/5A) EF relay using standard inverse characteristics

D.4

7SJ8031

Outgoing Capacitor Feeder 12kV Circuit (400/5A) EF relay using standard inverse characteristics

D.3A

Siemens

Outgoing Cable Feeder 12kV Circuit (800/5A) EF relay using standard Definite characteristics

D.3

7SJ8031

Outgoing Cable Feeder 12kV Circuit (400/5A) EF relay using standard Definite characteristics

D.2A

Siemens

Outgoing Aux Trafo Feeder 12kV Circuit(with newly proposed CT) EF relay using standard inverse characteristics

D.2

7SJ8031

13.3 MVA, Tertiary Windig TEF protection using standard inverse characteristics

SIEMENS Energy Sector T&D Projects/Engineering

Page 36 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

D.8

40 MVA Transformer 132 kV Circuit Neutral Protection (HV Side) EF protection using standard inverse characteristics

D.9

7SJ8011

Siemens

40 MVA Transformer EF for NGR EF protection using standard inverse characteristics

P14NB16A7C0500A

Shanghai xinguang

SIEMENS Energy Sector T&D Projects/Engineering

Page 37 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.1

500 KVA Aux Transformer 12kV side Earth Fault Protection

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

Plug Setting: Min. fault as percentage of rated current

=

Aux Trafo. rated current

=

800 /

400 /

5A

20% 500kVA x 0.2 ÷

(√3

x 12 kV)

4.81 A = 4.8 A

Corresponding secondary current

÷ 400

÷5

= 0.06 A

≈

= 0.06 A

pickup setting

1.2% x In

= 0.25 to 20 A (steps 0.01) = 0.25 A

Hence Pickup setting

(Note:Due to limitation of Relay range ,we propose to select Pick up value 0.25 instead of 0.06) B.

Time Multiplier Setting: Fault current of a transformer at 12kV side

= 1500A

(equal to NGR Rating) = 1500A

Multiples of Fault Current

÷( 400

/5

x 0.25)

= 75.00 A \ As per IEC Normal Inverse characteristic

0.14

=

÷ [(20)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec.

at TMS = 1

= 0.200

For Selectivity Operating time considered Since, 2.27 x TMS

= 0.200 sec. TMS = 0.088

Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time

= 2.270

x 0.090

0.090 0.204 sec.

C. Settings recommended : General Data Address

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

400A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

400A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Function

Value

1307

51N Pickup

0.25A

0.250 to 20A

1308

51N Time Dial

0.09A

0.05 to 3.2 sec

1311

51N IEC Curve

SI**

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

15.0 A 0 sec

0.25 to 175A

Address

50N-2 Delay

Range

0 to 60 sec

** Note: Values has been modified as per site (GSM/GSP) recommendation. SIEMENS Energy Sector T&D Projects/Engineering

Page 38 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.1A

500 KVA Aux Transformer 12kV side Earth Fault Protection Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

100 /

50 /

5A

(Note:Due to limitation of relay range ,we propose 100/5A ratio. Currently both settings have been (provided. However, 800/400/5A CT settings will be removed after confirmation)

A.

Plug Setting: Min. fault as percentage of rated current

=

Aux Trafo. rated current

=

20% 500kVA

x 0.2 ÷

(√3

x 12 kV)

4.81 A = 4.8 A

Corresponding secondary current

÷ 100

÷5

= 0.24 A = 0.24 A

pickup setting

≈

4.8% x In

= 0.25 to 20 A (steps 0.01)

B.

Hence Pickup setting

= 0.25 A

Time Multiplier Setting: Fault current of a transformer at 12kV side

= 1500A

(equal to NGR Rating) = 1500A

Multiples of Fault Current

÷( 100

/5

x 0.25)

= 240.00 A \ As per IEC Normal Inverse characteristic

0.14

=

÷ [(20)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec. For Selectivity Operating time considered

= 0.200

Since, 2.27 x TMS

= 0.200 sec.

at TMS = 1

TMS = 0.088 Available setting

= 0.05 to 3.2s (steps 0.01s)

≈ ≈

Hence the selected TMS Operating time

= 2.270

x 0.090

0.090 0.204 sec.

C. Settings recommended : General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

100A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

100A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Function

Value

Range

1307

51N Pickup

0.25A

0.250 to 20A

1308

51N Time Dial

0.090

0.05 to 3.2 sec

1311

51N IEC Curve

NI

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

66A** 0 sec

0.25 to 175A

50N-2 Delay

0 to 60 sec

**1.1 x (Fault current/ CT ratio) = 1.1 x (1200/100/5) =66A Note:As per client's comment,Definite time curve can also be consider.The operating time t=0.2 sec will be considered for Definite time. SIEMENS Energy Sector T&D Projects/Engineering

Page 39 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.2

12 kV Outgoing Cable Feeder Earth Fault Protection (Settings at CT ratio 400/5 A)

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

800 /

Plug Setting: Min. fault as percentage of rated current

=

20%

Feeder rated current

= 400 A

Corresponding secondary current

= 80.0 A

400 /

x 0.2

5A

= 80 A ÷ 400

÷5

= 1.00 A

≈

= 1.00 A

Hence selected pickup setting

20.0% x In

= 0.25 to 20 A (steps 0.01)

B.

Recommneded Relay settings

= 20.0% x In

Hence selected pickup setting

= 1.00 A

Time Multiplier Setting: Fault current contributed

=

40 MVA

x1 ÷

(√3

by transformer

= 10307.99 A

Multiples of Fault Current

= 10307.99

x 12 kV

x 0.187)

÷( 400

/5

x 1.00)

= 128.85 A \ As per IEC Normal Inverse characteristic

0.14

=

÷ [(20)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec.

at TMS = 1

= 0.200

For Selectivity Operating time considered Since, 2.27 x TMS

= 0.200 sec. TMS = 0.088

Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time

= 2.270

x 0.090

0.090 0.204 sec.

C. Settings recommended : General Data Address

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

400A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

400A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Function

Value

1307

51N Pickup

1.00 A

0.250 to 20A

1308

51N Time Dial

0.090

0.05 to 3.2 sec

1311

51N IEC Curve

NI

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

30A** 0 sec

0.25 to 175A

50N-2 Delay

Range

0 to 60 sec

**Note: As per KE Practice, since fault current is 2400A at primary side, therefore high set will be considered (fault current/CT ratio)=(2400/400/5)=30A at secondary side. SIEMENS Page 40 + Energy Sector T&D Projects/Engineering

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.2A

12 kV Outgoing Cable Feeder Earth Fault Protection (Settings at CT ratio 800/5 A)

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

800 /

Plug Setting: Min. fault as percentage of rated current

=

20%

Feeder rated current

= 800 A

Corresponding secondary current

= 160.0 A

400 /

5A

x 0.2

160 A

= ÷ 800

÷5

= 1.00 A

≈

= 1.00 A

Hence selected pickup setting

20.0% x In

= 0.25 to 20 A (steps 0.01)

B.

Recommneded Relay settings

= 20.0% x In

Hence selected pickup setting

= 1.00 A

Time Multiplier Setting: Fault Current contributed by

=

40 MVA

x1 ÷

(√3

transformer

= 10307.99 A

Multiples of Fault Current

= 10308.0

x 12 kV

x 0.187)

÷( 800

/5

x 1.00)

= 64.42 A \ As per IEC Normal Inverse characteristic

=

0.14

÷ [(20)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec.

at TMS = 1

= 0.200

For Selectivity Operating time considered Since, 2.27 x TMS

= 0.200 sec. TMS = 0.088

Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time

= 2.270

x 0.090

0.090 0.204 sec.

C. Settings recommended : General Data Address

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

800A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

800A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Function

Value

Range

1307

51N Pickup

0.5A**

0.250 to 20A

1308

51N Time Dial

0.080**

0.05 to 3.2 sec

1311

51N IEC Curve

SI**

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

2.77A** 0.1 sec**

0.25 to 175A

50N-2 Delay

0 to 60 sec

** Note: Values has been modified as per site (GSM/GSP) recommendation. SIEMENS Page 41 + Energy Sector T&D Projects/Engineering

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.3

4 MVA, 12 kV Capacitor Feeder Earth Fault Protection

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

800 /

Min. fault as percentage of rated current

=

20%

Feeder rated current

=

4MVA

400 /

5A

Plug Setting: x 0.2 ÷

(√3

x 12 kV)

= 38.49 A = 38.49 A

Corresponding secondary current

÷ 400

÷5

= 0.48 A

≈ 9.6% x In

= 0.48 A

Hence selected pickup setting

= 0.25 to 20 A(steps 0.01)

B.

Recommneded Relay settings

= 10.0% x In

Hence selected pickup setting

= 0.50 A

Time Multiplier Setting: Fault Current contributed by

=

transformer

= 10307.99 A

Multiples of Fault Current

= 10307.99

40 MVA

x1 ÷

(√3 x 12 kV

÷( 400

/5

x 0.187)

x 0.50)

= 257.70 A \ As per IEC Normal Inverse characteristic

0.14

=

÷ [(20)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec.

at TMS = 1

= 0.200

Operating time for 12kV Capacitor Feeder Since, 2.27 x TMS

= 0.200 sec. TMS = 0.088

Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time

= 2.270

x 0.090

0.090 0.204 sec.

C. Settings recommended : General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

400A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

400A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Function

Value

1307

51N Pickup

0.25A

0.250 to 20A

1308

51N Time Dial

0.09A

0.05 to 3.2 sec

1311

51N IEC Curve

1317 1318

50N-2 Pickup 50N-2 Delay

Range

SI

Norm,Very,Ext,long

2.77A 0 sec

0.25 to 175A 0 to 60 sec

** Note: Values has been modified as per site (GSM/GSP) recommendation. SIEMENS Energy Sector T&D Projects/Engineering

Page 42 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.3A

4 MVA, 12 kV Capacitor Feeder Earth Fault Protection

A.

Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

=

800 /

Min. fault as percentage of rated current

=

20%

Feeder rated current

=

4MVA

400 /

5A

Plug Setting: x 0.2 ÷

(√3

x 12 kV)

= 38.49 A = 38.49 A

Corresponding secondary current

÷ 800

÷5

= 0.24 A

≈ 4.8% x In

= 0.24 A

Hence selected pickup setting

= 0.25 to 20 A(steps 0.01)

B.

Recommneded Relay settings

= 5.0% x In

Hence selected pickup setting

= 0.25 A

Time Multiplier Setting: Fault Current contributed by

=

transformer

= 10307.99 A

Multiples of Fault Current

= 10307.99

40 MVA

x1 ÷

(√3 x 12 kV

÷( 800

/5

x 0.187)

x 0.25)

= 257.70 A \ As per IEC Normal Inverse characteristic

0.14

=

÷ [(20)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec.

at TMS = 1

= 0.200

Operating time for 12kV Capacitor Feeder Since, 2.27 x TMS

= 0.200 sec. = 0.088

TMS Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time

= 2.270

x 0.090

0.090 0.204 sec.

C. Settings recommended : General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

400A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

400A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Function

Value

1307

51N Pickup

0.25 A

0.250 to 20A

1308

51N Time Dial

0.09

0.05 to 3.2 sec

1311

51N IEC Curve

NI

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

2.77 A 0 sec

0.25 to 175A

50N-2 Delay

**1.1 x (Fault current/ CT ratio) = 1.1 x (10459.24/800/5) = SIEMENS Energy Sector T&D Projects/Engineering

Range

0 to 60 sec

72A

Page 43 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.4

40 MVA Transformer, 12 kV Incomer Earth Fault Protection(Trafo. LV side) With NGR

A.

Relay Type:

=

CT Ratio

=

Plug Setting: Min. fault as percentage of rated current

2500 /

5A

20%

= =

40 MVA x 0.2 ÷

=

384.90 A

=

384.9 A

=

0.77 A

=

0.77 A

=

0.25 to 20 A (steps 0.01)

Recommneded Relay settings

=

16.0% x In

Hence selected pickup setting

≈

0.80 A

Time Multiplier Setting: Fault current of a transformer at 12kV side

=

1.5 kA

=

1500

=

3.75 A

=

0.14

Transformer LV winding rated current Corresponding secondary current Hence selected pickup setting

B.

7SJ8031-5EB00-1FB0

(√3

x 12 kV)

÷ 2500

≈

÷5

15.4% x In

(As per client comment)

(equal to NGR Rating) Multiples of Fault Current As per IEC Normal Inverse characteristic

÷( 2500 ÷ [(3.75)

/5 0.02

x 0.80)

-1]

(Refer 7SJ80 manual page 384) Operating time Operating time for transformer 12 kV side Since, 5.23 x TMS

=

5.226 sec.

=

5.23 sec.

=

1.500

=

1.500 sec.

at TMS = 1

=

0.287

Available settings

=

0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

0.290

TMS

Operating time

= 5.230

x 0.290

1.517 sec.

Settings recommended : General Data Address

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

2500A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

2500A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Value

Function

1307

51N Pickup

1308

51N Time Dial

1311

51N IEC Curve

1317 1318

50N-2 Pickup 50N-2 Delay

Range

0.55A**

0.250 to 20A

0.09**

0.05 to 3.2 sec

SI**

Norm,Very,Ext,long

2.77A** 0.4 sec

0.25 to 175A 0 to 60 sec

** Note: Values has been modified as per site (GSM/GSP) recommendation. SIEMENS Energy Sector T&D Projects/Engineering

Page 44 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.4A

A.

40 MVA Transformer, 12 kV Incomer Earth Fault Protection(Trafo. LV side) Without NGR Relay Type:

=

CT Ratio

=

2500 /

=

40 MVA

=

384.90 A

=

384.9 A

=

0.77 A

=

0.77 A

=

0.25 to 20 A (steps 0.01)

Recommneded Relay settings

=

16.0% x In

Hence selected pickup setting

≈ 0.80 A

Time Multiplier Setting: Fault current of a transformer at 12kV side

=

40 MVA

=

10307.99 A

=

10308.0

=

25.77 A

=

0.14

Plug Setting: Min. fault as percentage of rated current

5A

20%

=

Transformer LV winding rated current Corresponding secondary current Hence selected pickup setting

B.

7SJ8031-5EB00-1FB0

Multiples of Fault Current As per IEC Normal Inverse characteristic

x 0.2 ÷

(√3

x 12 kV)

÷ 2500

≈

÷5

15.4% x In

x1 ÷

(√3

÷( 2500

x 12 kV

/5

÷ [(20.00)

0.02

x 0.187)

x 0.80)

-1]

(Refer 7SJ80 manual page 384) =

2.267 sec.

=

2.27 sec.

=

0.900

=

0.900 sec.

=

0.396

Available settings

=

0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

0.400

Operating time

Operating time for transformer 12 kV side Since, 2.27 x TMS TMS

Operating time

= 2.270

x 0.400

at TMS = 1

0.908 sec.

Settings recommended : General Data Address

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

2500A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

2500A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Value

Function

Range

1307

51N Pickup

0.8A

0.250 to 20A

1308

51N Time Dial

0.4

0.05 to 3.2 sec

1311

51N IEC Curve

NI

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

23.0A** 0.4 sec

0.25 to 175A

50N-2 Delay

**1.1 x (Fault current/ CT ratio) = 1.1 x (10459.24/2500/5) = SIEMENS Energy Sector T&D Projects/Engineering

0 to 60 sec

23A

Page 45 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.5

40 MVA Transformer, 12 kV Circuit Neutral Protection(LV Side) with NGR = 7SJ8031-5EB00-1FB0 Relay Type: =

CT Ratio : A.

2500 /

5A

Plug Setting : Min. fault as percentage of rated current

20%

=

Transformer LV winding rated current

40 MVA x 0.2 ÷

=

(√3

x 12 kV)

= 384.90 A Corresponding secondary current

= 384.90 A

Hence selected pickup setting

≈ 0.77 ≈ 0.77 A

÷ 2500

÷5

≈ 15.4% x In

= 0.25 to 20 A (steps 0.01)

B.

Recommneded Relay settings

= 16.0% x In

Hence selected pickup setting

≈ 0.80 A

Time Multiplier Setting: Fault current of a transformer at 12kV side

=

1500.0 A (As per client comment)

(equal to NGR Rating) = 1500.0

Multiples of Fault Current

÷( 2500

/5

x 0.80)

= 3.75 A As per IEC Normal Inverse characteristic

0.14

=

÷ [(3.8)

0.02

-1]

(Refer 7SJ80 manual page 384) = 5.226 sec.

Operating time

= 5.23 sec. Operating time of the Incomer Relay 12 kV side

= 1.517

Operating time for Trafo 12kV EF Since, 5.23 x TMS

= 1.517

at TMS = 1

= 1.517 sec. TMS = 0.290

Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time

= 5.230

x 0.290

0.290 1.517 sec.

C.

Settings recommended General Data Address

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

2500A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

2500A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Function

Value

Range 0.250 to 20A

1307

51N Pickup

0.8A

1308

51N Time Dial

0.29

0.05 to 3.2 sec

1311

51N IEC Curve

NI

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

2.64A** 0.4 sec

0.25 to 175A

50N-2 Delay

**1.1 x (Fault current/ CT ratio) = 1.1 x (1200/2500/5) = SIEMENS Energy Sector T&D Projects/Engineering

0 to 60 sec

2.64A

Page 46 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.5A

A.

40 MVA Transformer, 12 kV Circuit Neutral Protection(LV Side) Without NGR Relay Type:

= 7SJ8031-5EB00-1FB0

CT Ratio :

=

2500 /

5A

Plug Setting : Min. fault as percentage of rated current

20%

=

Transformer LV winding rated current

40 MVA

=

x 0.2 ÷

(√3

x 12 kV)

= 384.90 A = 384.90 A

Corresponding secondary current

÷ 2500

÷5

≈ 0.77 ≈ 0.77 A

Hence selected pickup setting

≈

15.4% x In

= 0.25 to 20 A (steps 0.01)

B.

Recommneded Relay settings

= 16.0% x In

Hence selected pickup setting

≈ 0.80 A

Time Multiplier Setting: Fault current of a transformer

=

40 MVA

x1 ÷

(√3

at 12kV side

= 10291.45 A

Multiples of Fault Current

= 10291.4

x 12 kV

x 0.187)

÷( 2500

/5

x 0.80)

= 25.73 A As per IEC Normal Inverse characteristic

0.14

=

÷ [(20.0)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec. Operating time of the Incomer Relay 12 kV side

= 1.000

Operating time for Trafo 12kV EF Since, 2.27 x TMS

= 1.000

at TMS = 1

= 1.000 sec. TMS = 0.441

Available setting

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time

= 2.270

x 0.450

0.450 1.022 sec.

C.

Settings recommended General Data Address

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

2500A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

2500A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Function

Value

Range 0.250 to 20A

1307

51N Pickup

0.8A

1308

51N Time Dial

0.45

0.05 to 3.2 sec

1311

51N IEC Curve

NI

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

23A** 0.4 sec

0.25 to 175A

50N-2 Delay

**1.1 x (Fault current/ CT ratio) = 1.1 x (10459.24/2500/5) = SIEMENS Energy Sector T&D Projects/Engineering

0 to 60 sec

23A

Page 47 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.6

40 MVA Transformer, 132 kV Trafo(HV Side) Earth Fault Protection

A.

B.

Relay Type:

= 7SJ8011-5EB20-1FA0

CT Ratio

=

200 /

Plug Setting: Min. fault as percentage of rated current

=

20%

Transformer HV winding rated current

=

40 MVA

1A

x 0.2 ÷

(√3

=

41.17 A

Corresponding secondary current

=

41.17 A 0.21 A

Hence selected pickup setting

≈ ≈ =

0.05 to 4 A (steps 0.01)

x112 kV)

÷ 200

÷1

≈ 20.6% x In

0.21 A

Recommneded Relay settings

= 20.6% x In

Hence selected pickup setting

≈ 0.21 A

Time Multiplier Setting: = 40 MVA x 1 ÷

Fault Current contributed by

(√3

x 112 kV

x 0.187)

÷( 200

/1

= 1102.46 A

a transformer at 132kV side

= 1102.5 As per IEC Normal Inverse characteristic

=

26.78 A

=

0.14

÷ [(20.00)

0.02

x 0.21)

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec.

at TMS = 1

For selectivity to earth fault protection, tripping time is choosen Since, 2.27 x TMS

= 1.00

Available settings

= 0.05 to 3.2s (steps 0.01s)

Hence the selected TMS

≈ ≈

Operating time

= 2.270

= 1.00 sec.

x 0.450

0.441

≈

0.450

1.022 sec.

C. Settings recommended : General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

200A

0205

CT Rated Secondary Current

1A

0217

IE-CT Rated Secondary Current

200A

0218

IE-CT Rated Secondary Current

1A

Earthfault Protection Address

Function

Value

1307

51N Pickup

0.21A

0.05 to 4A

1308

51N Time Dial

0.45

0.05 to 3.2 sec

1311

51N IEC Curve

NI

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

35 A Blocked,infinity

0.05 to 35A

50N-2 Delay

**1.1 x (Fault current/ CT ratio) = 1.1 x (1102.5/200/1) = SIEMENS Page 48 + Energy Sector T&D Projects/Engineering

Range

0 to 60 sec

6.1A EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.7

13.3 MVA Tertiary Winding Earth Fault Protection

A.

Relay Type:

= 7SJ8011-5EB20-1FA0

CT Ratio :

=

500 /

5A

Plug Setting : Min. fault as percentage of rated current

= 20%

Transformer tertiary winding rated current

= 13 MVA

÷

(√3 x 12 kV)

= 639.90 A = 640 / 1.732

0.20 A

= 370 X

= 74.00 A Corresponding secondary current

= 74.00 A

÷ 500

Hence selected pickup setting

= 0.74 A

≈ 14.8% x In

÷5

= 0.25 to 20 A(steps 0.01)

B.

Recommneded Relay settings

= 15.0% x In

Hence selected pickup setting

≈ 0.75 A

Time Multiplier Setting: Fault current

= 5.1KA

Multiples of Fault Current

= 5100.0

÷( 500

/5

x 0.75)

= 68.00 A = 0.14

As per IEC Normal Inverse characteristic

÷ [(20)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec. Tripping time choosen

= 0.500

Since, 2.27 x TMS

= 0.500 sec.

at TMS = 1

TMS = 0.220 Available setting

= 0.05 to 3.2s (steps 0.01s)

≈ ≈

Hence the selected TMS Operating time C.

= 2.270

x 0.230

0.230 0.522 sec.

Settings recommended :

General Data Function

Value

0214

Address

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

500A

0205

CT Rated Secondary Current

5A

0217

IE-CT Rated Secondary Current

500A

0218

IE-CT Rated Secondary Current

5A

Earthfault Protection Address

Function

Value

1307

51N Pickup

0.75A

0.250 to 20A

1308

51N Time Dial

0.23

0.05 to 3.2 sec

1311

51N IEC Curve

NI

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

56.1A** 0

0.25 to 175A

50N-2 Delay 56.1A **1.1 x (Fault current/ CT ratio) = 1.1 x (5100/500/5) = SIEMENS Page 49 + Energy Sector T&D Projects/Engineering

Range

0 to 60 sec

EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.8

40 MVA Transformer 132kV Circuit Neutral Protection(HV Side)

A.

Relay Type:

= 7SJ8011-5EB20-1FA0

CT Ratio :

=

200 /

1A

Plug Setting : Min. fault as percentage of rated current

= 20%

Transformer HV winding rated current

= 40 MVA

x 0.2 ÷ (√3

x112 kV)

= 41.17 A

B.

Corresponding secondary current

= 41.17 A

÷ 200

Hence selected pickup setting

≈ 0.21 A ≈ 0.21 A

≈ 20.6% x In

Recommneded Relay settings

= 20.6% x In

Hence selected pickup setting

≈ 0.21 A

TMS Setting : Fault Current contributed by

40 MVA x 1 ÷

=

÷1

(√3 x 112 kV x 0.187)

a transformer at 132kV side

= 1102.46 A

Multiples of fault current

= 1102.5

÷( 200

/1

x 0.21)

= 26.78 As per IEC Normal Inverse characteristic

0.14 ÷

=

[(20.00)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.27 sec. = 2.27 sec.

Operating time Hence operating time for EF Since, 2.27 x TMS TMS

at TMS = 1

=

1.100

=

1.100

=

1.100 sec.

=

0.485

sec.

Available settings

= 0.05 to 3.2s (steps 0.01s)

Selected TMS setting

≈ ≈

Revised operating time

= 2.267

x 0.490

0.490 1.111 sec.

C. Settings recommended : General Data Address

Function

Value

0214

Rated Frequency

50HZ

0209

Phase Sequence

L1,L2,L3

0204

CT Rated Primary Current

200A

0205

CT Rated Secondary Current

1A

0217

IE-CT Rated Secondary Current

200A

0218

IE-CT Rated Secondary Current

1A

Earthfault Protection Address

Function

Value

Range

1307

51N Pickup

0.21A

0.05 to 4A

1308

51N Time Dial

0.49

0.05 to 3.2 sec

1311

51N IEC Curve

NI

Norm,Very,Ext,long

1317 1318

50N-2 Pickup

35.0 A Blocked,Infinity

0.05 to 35A

50N-2 Delay

**1.1 x (Fault current/ CT ratio) = 1.1 x (1118.64/200/1) = SIEMENS Energy Sector T&D Projects/Engineering

0 to 60 sec

6.1A

Page 50 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS D.9

A.

40 MVA Transformer, EF Relay for NGR Relay Type:

= P14NB16A7C0500A

CT Ratio :

=

100 /

5A

Plug Setting : Min. fault as percentage of rated current Considering max. current through the circuit

20%

=

= 50 A

x 0.2

= 10 A Corresponding secondary current

= 10 A

÷ 100

Hence selected pickup setting

≈ 0.50 ≈ 0.10 A

≈

÷5

= 0.05 to 4 x In (steps 0.01x In ) = 0.10 x In B.

Time Multiplier Setting:

Fault current of NGR

= 1500.0 A

Multiples of Fault Current

= 1500.0

÷( 100

/5

x 0.10)

= 750.00 A As per IEC Normal Inverse characteristic

0.14

=

÷ [(20.0)

0.02

-1]

(Refer 7SJ80 manual page 384) = 2.267 sec.

Operating time

= 2.27 sec.

at T = 1

Operating time of the Incomer Relay 12 kV side

= 1.500

+ 0.25

Operating time for NGR EF

= 1.750

Since, 2.27 x T

= 1.750 sec. T = 0.771

Available setting

= 0.025 to 1.2s (steps 0.005)

Hence the selected T

≈ ≈

Operating time C.

= 2.270

x 0.780

0.780 1.771 sec.

Settings recommended Function IN1>1 Current IN1>1 Time IN1>1 Function

SIEMENS Energy Sector T&D Projects/Engineering

Value

Range

0.10 x In

0.05 to 4 x In

0.78

0.025 to 1.2 sec

NI Page 51 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

Operating Time

PMS

TMS

0.2 sec.

0.5A**

0.080**

0.2 sec.

0.25 A

0.090

0.2 sec.

1.0A

0.090

0.2 sec.

1.0A

0.090

0.2 sec.

0.5A**

0.08**

0.2 sec.

0.25 A

0.090

1.5 sec.

0.55A**

0.09**

0.9 sec.

0.8A

0.4

0.8A

0.24

1.0 sec.

0.8A

0.45

1.0 sec.

0.21A

0.45

TEF protection using standard inverse characteristics

0.5 sec.

0.75A

0.23

40 MVA Transformer 132 kV Circuit Neutral Protection (HV Side)

1.1 sec.

0.21A

0.49

1.8 sec.

0.10 A

0.780

Results Summary

D.1

Outgoing Aux Trafo Feeder 12kV Circuit EF relay using standard inverse characteristics

D.1A

Outgoing Aux Trafo Feeder 12kV Circuit(with newly proposed CT) EF relay using standard inverse characteristics

D.2

Outgoing Cable Feeder 12kV Circuit (400/5A) EF relay using standard Definite characteristics

D.2A

Outgoing Cable Feeder 12kV Circuit (800/5A) EF relay using standard Definite characteristics

D.3

Outgoing Capacitor Feeder 12kV Circuit (400/5A) EF relay using standard inverse characteristics

D.3A

Outgoing Capacitor Feeder 12kV Circuit(800/5A) EF relay using standard inverse characteristics

D.4

40 MVA Transformer 12kV Incomer Circuit(Trafo. LV Side) with NGR EF relay using standard inverse characteristics

D.4A

40 MVA Transformer 12kV Incomer Circuit(Trafo. LV Side) without NGR EF relay using standard inverse characteristics

D.5

40 MVA Transformer 12kV Circuit Neutral Protection with NGR (LV Side) EF protection using standard inverse characteristics

D.5A

40 MVA Transformer 12kV Circuit Neutral Protection Witout NGR (LV Side) EF protection using standard inverse characteristics

D.6

40 MVA Transformer 132 kV Circuit(Trafo HV Side) EF relay using standard inverse characteristics

D.7

D.8

1.5 sec.

13.3 MVA, Tertiary Windig

EF protection using standard inverse characteristics D.9

40 MVA Transformer EF for NGR EF protection using standard inverse characteristics

SIEMENS Energy Sector T&D Projects/Engineering

Page 52 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

AVR Relay

SIEMENS Energy Sector Projects/Engineering

Page 53 + EM-TS PROJECTS/A5175/Relay settings

SIEMENS

E.

E.1

AVR Relay

AVR Relay

SIEMENS Energy Sector Projects/Engineering

Tapcon 230 Expert

MR

Page 54 + EM-TS PROJECTS/A5175/Relay settings

SIEMENS

AVR Setting Calculation Data: I ). Relay type

= Tapcon 230 Expert

II ). Transformer Rating

= 40

MVA

III ). Voltage at maximum tap

Umax

= 151.80

kV

IV ). Voltage at minimum tap

Umin

= 112.20

kV

V ). Transformation Ratio

= 132 /12

VI ). Tap changing Range

= + 15 %

VII ).Vector Group

= YNyn0(d11)

to

- 15 %

Setting Parameters

Function

Value

Range

Desired Voltage

100V

Bandwith

5%

0.5 to 9 %

Delay time T1

40 sec

0 to 60 sec

Control Reponse Time

Linear

Linear / Integral

Under Voltage

90%

60 to 100 %

Under Voltage Delay time U <

10 sec

0 to 20 sec

Over Voltage

110%

100 to 140 %

EM-TS PROJEC

SIEMENS Energy Sector Projects/Engineering

Page 55 + EM-TS PROJECTS/A5175/Relay settings

SIEMENS

Capacitor Feeder Un Balance Protection

SIEMENS Energy Sector Projects/Engineering

Page 56 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

F.1

2x4 MVA, 12 kV Capacitor Bank Unbalance Protection Relay Type

= 7SJ8031-5EB00-1FB0

CT Ratio

= 20 / 5A

, 20 VA, Cl : 10P10

Capacitor Data: ▪

Rated Power

= 8

MVAr

▪

Rated Voltage

= 12.00

kV

▪

Rated Current

= 384.90

A

▪

Frequency

= 50

Hz

f

General:

As per existing KE practice the unbalance setting considered For Alarm and Trip

C.

Neutral unbalance current setting considered for Alarm

=

2A

A

(Secondary Current)

Unbalance time delay setting considered for alarm

=

5.000

sec

Neutral unbalance current setting considered for Trip

=

3.7A

A

Unbalance time delay setting considered for Trip

=

0.300

sec

(Secondary Current)

Settings recommended :

Address

Function

Value

Range

1204

51 Pickup

2A

0.10 to 4A

1205

51 Time Dial

5 sec

0 to 60 sec

1202

50-2 Pickup

3.7A

0.10 to 35A

50-2 Delay

0.3 sec

0 to 60 sec

1203

SIEMENS Energy Sector Projects/Engineering

Page 57 + EM-TS PROJECTS /A5175/Relay Settings

SIEMENS

Annexure

SIEMENS Energy Sector Projects/Engineering

Page 58 + EM-TS PROJECTS /A5175/Relay Settings

132/12kV KEPZ AIS S/S

IDMT Overcurrent Curves (HV & LV Overcurrent with outgoing feeders(Aux Trafo,Capacitor,Cable) 1000

100

10

Incomer (Trafo LV)

t[s]

Outgoing(Aux Trafo) HV side

1

Outgoing(Capacitor) Outgoing(Cable 400/5 Tap)

1

Outgoing(Cable 800/5 Tap) Transformer Dmage Curve

0.1

0.01 10

100

1000

10000 I[A]

100000

1000000

10000000

132/12kV KEPZ AIS S/S

IDMT Earth Fault Curves (HV & LV Earthfault with outgoing feeders(Aux trafo,Capacitor,Cable ) 1000

100

10 t[s]

Incomer With NGR Outgoing(Aux Trafo) HV Side

1

Outgoing(Capacitor) Incomer Without NGR Outgoing(Cable 400/5 Tap)

Cable 400/5

Outgoing(Cable 800/5 Tap)

Cable 800/5

0.1

0.01 10

100

1000

10000 I[A]

100000

1000000

10000000

132/12kV KEPZ AISS/S

IDMT Earth Fault Curves (HV & LV Neutral with outgoing feeders(Aux trafo,Capacitor,Cable) 1000

100

10 t[s]

Outgoing(Aux Trafo) Outgoing(Cable 400/5 Tap) Outgoing (Cable 800/5 Tap)

1

Outgoing(Capacitor) LV Neutral with NGR LV Neutral Without NGR

Cable 800/5

Cable 400/5

HV Neutral

0.1

0.01 10

100

1000

10000 I[A]

100000

1000000

10000000

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