3.1.1.Fault Calculations for Over Current

ITC LIMITED PAPERBOARDS & SPECIALITY PAPERS DIVISION

Technical ReportProtective Relay Co-ordination

February – 2006

By

Engineering Service Excellence

Elsytec Power Projects Pvt Ltd Consultancy & Engineering Services

Chennai-600 083

UNIT - KOVAI

Contents

S.No Description Page No

1. Introduction 1

2. Executive Summary 2

3. Relay Settings and Timings

3.1. Over Current Relay Settings

3.1.1. Fault Calculations 4

3.1.2. Recommended Over Current Settings 7

3.1.3. Existing Relay Settings for Over Current 13

3.1.4. Time-Current Characteristics Curves 19

3.2. Earth Fault Relay Settings

3.2.1. Recommended Earth Fault Relay Settings 22

3.2.2. Existing Relay Settings 30

4 Comparison of Existing and Recommended Settings

4.1. Over Current Settings 36

4.2. Earth Fault Settings 42

5 Proposed additional Relays recommended by Elsytec 48

6. Recommended Settings for Over Current and Earth Fault 49

7. Relay Catalogues

8. Single Line Diagrams

6.1. Single line Diagram Showing Over Current Relay Setting & Timings. (Drg.No: EPPPL/1188/ITC/001)

6.2. Single line Diagram Showing Earth Fault Relay Setting & Timings. (Drg.No: EPPPL/1188/ITC/002)

1. INTRODUCTION

1. INTRODUCTION

Elsytec Power Projects Pvt Ltd Chennai was asked to study the protective relaying at ITC

Kovai Unit in the wake of recent disturbances in grid and local faults in the plant which caused

tripping of their in plant turbine as well as Utility supply. Also any addition /alteration required to

protective relaying scheme were asked to be identified in the light of their proposed export of

power from in plant generator to Grid.

A snap study was undertaken by Elsytec Power Projects Pvt Limited by making a visit to

their plant on 16th and 17th of Jan 2006 and Electrical system details along with protection scheme

were studied by holding discussions with their engineers.

Following are the high lights of discussion and study.

• Three major tripping that happened recently were discussed in depth and details analyzed

• The analysis revealed serious shortcomings in the maintenance of system which led to the

faulty tripping of in plant generator and Grid

• Failure to connect/test certain protective relays

• Necessity to tighten the preventive maintenance checks which are vulnerable in nature

• Necessity to check the relay co-ordination as well as test and calibrate the relays

• Necessity check and revamp earthing system

This report details the present settings and analyses the tripping scenarios in the faults that

affected the plants as well as scenarios faults at various levels. The report also details the existing

settings, their tripping times, previous consultant’s settings and their tripping time and under

various scenarios and Elsytec’s suggested modification in settings where necessary.

Report is divided in to following sections:

• Fault level calculations

• Existing settings and tripping times and sequence during 3.0kV fault which crippled the

mill

• Tripping times for faults at various buses

• Elsytec’s suggested settings for proper Co-ordination with various settings in tabular

format and setting marked in SLD for easy reference

2.EXECUTIVE SUMMARY

2. EXECUTIVE SUMMARY

Present scenario Electrical Installation:

The H.T distribution of electrical installation is shown in Dwg No: TCE-4312A-733-

AU-3002 and it primarily consists of the following:

• 110 kV substation with its attendant breakers and CT’s and isolators

10/12.5 MVA 110kV/11kV transformer

• Neutral grounding Resistor to limit the earth fault current to 100 amps

• 11 KV switchgear SB1, SB2, SB3, SB4 comprising of withdrawal type Vacuum circuit

breaker switchgear

• Distribution Transformers ratings 1 MVA11kV/3.0 kV, 2.5MVA 11kV/433 volts,

2.0MVA 11kV/433V, 1.6MVA 11kV/433V and 315kVA, 11kV/433 volts

• All 433 volts secondary side neutral of transformer are solidly earthed

• 3.0 KV side of 11kV/3.0kV transformers neutral is resistor earthed to limit the current to

100 amps.

In plant Generator:

• 8MW 11kV extraction cum condensing set has been recently commissioned

• This is connected to associated vacuum circuit breaker board as shown in single line

diagram and hooked up to switchgear SB1 through tie breakers

• Condensing capacity is understood be 3.5 MW

• In plant generator can meet almost entire load of mill

Operating Scenario:

Normally the in plant generator and Grid are operated in parallel with necessary

protection and synchronizing facilities as shown single diagram. Marginal power to the tune of

500kW is drawn under healthy condition. In case of Grid disturbances Vector surge relay in 11kV

switchgear in SB1 islands the generator.

Protection scenario:

• All 11kV switchgear are provided with IDMTL electromagnetic relays of Type TJM

Easun Reyrolle make for their associated feeder protection with two over current and one

earth fault element

• Sensitive earth fault relays type MIT Easun Reyrolle make are also seen to be

provided in SB1 and appear to have not been connected and they appear to be in

service in Generator panel

• Vector surge relay of type MICOM GE Alstom make is in service at 11kV incomer

breaker of grid at SB1 and appears to be operating effectively

Recommendation and comments:

Elsytec Power projects Pvt Ltd has carried out detailed fault calculation study

and arrived at appropriate settings for the relay coordination consistent with plant

scenarios.

1. Basically the presents settings need adjustments to the new values indicated in the report

as present settings lack co ordination as given in Section-3.

2. It may be noted that incoming fault level and equivalent line impedance is ignored in this

fault calculations, as it is less than 10% of the available impedances of the mill circuits.

Also the cable impedances are not taken into consideration as these values are very small

to have any effect in the calculations.

3. Neutral CT and sensitive earth fault relay in 433 volts transformer neutral is to be

provided.

4. Sensitive earth fault relay in SB1 to be put in service. It should be noted that certain faults

in the system like 3.0 kV bus faults will not operate the O/C element of 11kV switchgear

as the fault current will not be sufficient to operate these relays and residual current in

sensitive earth fault relay can only serve as back up for 3kV system protective relays.

5. Please note Instantaneous settings in present settings are 99.99%, may be this is to be

switched off.

6. Reverse power element in MICOM relay to be disabled as and when the generator is

connected for export of power after discussing with TNEB for any other requirements for

export of power.

7. It is imperative D.C trip supply is maintained in healthy condition to avoid repetition of

failures and prevent fire risks and burn outs in future Possibly Trip supply supervision

relay and alarm at central place like T.G control panel can be installed apart from daily

check of “trip circuit healthy” lamp check manually on daily basis.

8. Earthing system integrity and maintain earth grid resistance with in 1ohm is a basic

requirement.

9. Relay and meter testing shall be carried out at periodic interval not exceeding 2 year is a

must.

3.RELAY SETTINGS & TIMINGS

Project : ITC Ltd PSPD - Kovai Unit ELSYTEC POWER PROJECTS PVT LTD,CHENNAI.

3.1. Over Current Relay Settings

Base 10 MVASB-1 (11kV)Transformer (10MVA) = 9.61 %TG(8MW) = 12 % SOURCE CURRENTT/F || TG = 5.33641832 % T/F 5.462%Zeq = 5.33641832 % TG 4.374Fault MVA = 187.392 MVA 9.836Short Circuit Current Isc = 9.836 kA

SB-2 (11kV)Transformer (10MVA) = 9.61 %TG (8MW) = 12 % SOURCE CURRENTT/F || TG = 5.33641832 % T/F 5.462%Zeq = 5.33641832 % TG 4.374Fault MVA = 187.392 MVA 9.836Short Circuit Current Isc = 9.836 kA

SB-3 (11kV)Transformer (10MVA) = 9.61 % SOURCE CURRENTTG(8MW) = 12 % T/F 5.462T/F || TG = 5.33641832 % TG 4.374%Zeq = 5.33641832 % 9.836Fault MVA = 187.392 MVAShort Circuit Current Isc = 9.836 kA

SB-4 (11kV)Transformer (10MVA) = 9.61 % SOURCE CURRENTTG(8MW) = 12 % T/F 5.462T/F || TG = 5.33641832 % TG 4.374%Zeq = 5.33641832 % 9.836Fault MVA = 187.392 MVAShort Circuit Current Isc = 9.836 kA

SB-5 (3kV)a Transformer (10MVA) = 9.61 % SOURCE CURRENTb TG(8MW) = 12 % T/F 0.5266985c Tr-2 (1MVA) = 50 % TG 0.422d a || b = 5.336 % 0.948e %Zeq = c+d = 55.336 %

Fault MVA = 18.071 MVAShort Circuit Current Isc = 3.478 kA

TG-PMCC-3 (3.3kV)a Transformer (10MVA) = 9.61 % SOURCE CURRENTb TG(8MW) = 12 % T/F 0.9300875c Aux.Tr-3 (2.5MVA) = 26 % TG 0.745d a || b = 5.33641832 % 1.675e %Zeq = c+d = 31.3364183 %


3.1.1. Fault Calculations - Phase Fault

3. Relay Settings and Timings

4


TG - PMCC1 (433V)a Transformer (10MVA) = 9.61 %b TG(8MW) = 12 % SOURCE CURRENTc Aux.Tr-1 (2MVA) = 40 % T/F 0.6428741d a || b = 5.33641832 % TG 0.515e %Zeq = c+d = 45.3364183 % 1.158


TG-1 Switchgear (11kV)Transformer (10MVA) = 9.61 % SOURCE CURRENTTG (8MW) = 12 % T/F 5.4616429T/F || TG = 5.33641832 % TG 4.374%Zeq = 5.33641832 % 9.836Fault MVA = 187.392 MVAShort Circuit Current Isc = 9.836 kA

PMCC-1 (433V)a Transformer (10MVA) = 9.61 %b TG(8MW) = 12 % SOURCE CURRENTc Tr-1 (2.5MVA) = 28 % T/F 0.8742874d a || b = 5.33641832 % TG 0.700e %Zeq = c+d = 33.3364183 % 1.574


PMCC-3 (433V)a Transformer (10MVA) = 9.61 %b TG(8MW) = 12 % SOURCE CURRENTc Tr-3 (2MVA) = 33.00 % T/F 0.7602591d a || b = 5.33641832 % TG 0.609e %Zeq = c+d = 38.3364183 % 1.369






5


PMCC-6 (433V)a Transformer (10MVA) = 9.61 %b TG(8MW) = 12 % SOURCE CURRENTc Tr-6 (315kVA) = 147.301587 % T/F 0.190946d a || b = 5.33641832 % TG 0.153e %Zeq = c+d = 152.638006 % 0.344


PMCC-7 (433V)a Transformer (10MVA) = 9.61 %b TG(8MW) = 12 % SOURCE CURRENTc Tr-7 (1.6MVA) = 41.9375 % T/F 0.6165262d a || b = 5.33641832 % TG 0.494e %Zeq = c+d = 47.2739183 % 1.110






DCD-10 (433V)a Transformer (10MVA) = 9.61 %b TG(8MW) = 12 % SOURCE CURRENTc Tr-10 (1.6MVA) = 41.875 % T/F 0.6173424d a || b = 5.33641832 % TG 0.494e %Zeq = c+d = 47.2114183 % 1.112


DCD- 11 (433V) a Transformer (10MVA) = 9.61 %b TG(8MW) = 12 % SOURCE CURRENTc Tr-11 (1.6MVA) = 41.625 % T/F 0.6206289d a || b = 5.33641832 % TG 0.497e %Zeq = c+d = 46.9614183 % 1.118


6

S.No SB No Description Relay Type Fault Current in kA

Primary Current in

CT(A)PS TMS I//Ipu Tripping Time

(Sec)

252-3 SB-1 TIE TO TG-1 SG CDD 31 4.374 500 1 0.7 8.75 0.98252-26 TG-1 TIE TO SB-1 CDD 31 4.374 500 1 0.7 8.75 0.98252-21 TG-1 I/C FROM TG CDG 31 4.374 600 1 0.85 7.29 1.3

252-25 TG-1 OG TO AUX.TR-3 CDG 31 9.836 200 1 0.3 49.18 0.31252-21 TG-1 I/C FROM TG CDG 31 4.374 600 1 0.85 9.10 1.15252-1 SB-1 I/C FOR SB-1 TJM 10 5.462 800 1 0.4 6.83 1.5152-1 SB-1 I/C FROM 110kV Line ICM 21 0.546 75 1 0.85 7.28 2.4252-3 SB-1 TIE TO TG-1 SG CDD 31 5.462 500 1 0.7 10.92 0.88

252-26 TG-1 TIE TO SB-1 CDD 31 5.462 500 1 0.7 10.92 0.88

352-1 SB-5 I/C FROM TR-2 TJM 10 3.478 200 1 0.1 17.39 0.26252-10 SB-3 OG TO TR-2 TJM 10 0.948 100 0.75 0.1 12.65 0.39252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 0.948 400 1 0.3 2.37 2.4252-1 SB-1 I/C FOR SB-1 TJM 10 0.527 800 1 0.4 0.66 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.053 75 1 0.85 0.70 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.422 500 1 0.7 0.84 Infinity

252-26 TG-1 TIE TO SB-1 CDD 31 0.422 500 1 0.7 0.84 Infinity252-21 TG-1 I/C FROM TG CDG 31 0.422 600 1 0.85 0.70 Infinity

352-2 SB-6 I/C FROM AUX.TR-3 CDG 31 5.583 500 1 0.1 11.17 0.13252-25 TG-1 OG TO AUX.TR-3 CDG 31 1.675 200 1 0.3 8.37 0.42252-21 TG-1 I/C FROM TG CDG 31 0.930 600 1 0.85 1.55 6252-1 SB-1 I/C FOR SB-1 TJM 10 0.745 800 1 0.4 0.93 infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.074 75 1 0.85 0.99 infinity252-3 TG-1 TIE TO TG-1 SG CDD 31 0.745 500 1 0.7 1.49 4

252-26 TG-1 TIE TO SB-1 CDD 31 0.745 500 1 0.7 1.49 4

452-2 SB-4 I/C FROM AUX.TR-2 CDG 31 29.411 3000 1 0.1 9.80 0.13252-23 SB-3 OG TO AUX.TR-2 CDG 31 1.110 200 1 0.3 5.55 0.48252-21 SB-1 I/C FROM TG CDG 31 0.493 600 1 0.85 0.82 Infinity

Fault at TG-PMCC-2 (433V)

Fault at TG-1 (11kV)

Fault at SB-5 (3kV)

Fault at TG-PMCC-3 (3.3kV)

8


Primary Current in


(Sec)

252-1 SB-1 I/C FOR SB-1 TJM 10 0.616 800 1 0.4 0.77 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 1 0.85 0.82 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.616 500 1 0.7 1.23 5

252-26 TG-1 TIE TO SB-1 CDD 31 0.616 500 1 0.7 1.23 5

452-11 PMCC1 I/C FROM SB2 CDG 31 39.997 4000 1 0.15 10.00 0.18252-8 SB-2 OG TO TR-1 NO RELAY252-7 SB-2 I/C FROM SB-1 TJM 10 1.574 150 1 0.3 10.50 0.88252-2 SB-1 OG TO SB-2 TJM 10 1.574 150 1 0.3 10.50 0.88252-1 SB-1 I/C FOR SB-1 TJM 10 0.874 800 1 0.4 1.09 12152-1 SB-1 I/C FROM 110kV Line ICM 21 0.087 75 1 0.85 1.17 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.700 500 1 0.7 1.40 5

252-26 TG-1 TIE TO SB-1 CDD 31 0.700 500 1 0.7 1.40 5252-21 TG-1 I/C FROM TG CDG 31 0.700 600 1 0.85 1.17 7

252-12 PMCC3 I/C FROM SB2 CDG 31 34.781 3000 1 0.15 11.59 0.18252-11 SB-3 OG TO TR-3 TJM 10 1.369 125 1 0.1 10.95 0.31252-9 SB-3 I/C FROM SB1 NO RELAY 1.369252-4 SB-1 OG TO SB-3 TJM 10 1.369 400 1 0.3 3.42 2.6252-1 SB-1 I/C OF SB-1 TJM 10 0.760 800 1 0.4 0.95 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.076 75 1 0.85 1.01 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.609 500 1 0.7 1.22 4.5252-26 TG-1 TIE TO SB-1 CDD 31 0.609 500 1 0.7 1.22 4.5252-21 TG-1 I/C FROM TG CDG 31 0.609 600 1 0.85 1.01 6

452-13 PMCC4 I/C FROM TR-4 CDG 31 34.963 3000 1 0.15 11.65 0.18252-12 SB-3 OG TO TR-4 TJM 10 1.376 125 1 0.1 11.01 0.31252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 1.376 400 1 0.3 3.44 2.6252-1 SB-1 I/C OF SB-1 TJM 10 0.764 800 1 0.4 0.96 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.076 75 1 0.85 1.02 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.764 500 1 0.7 1.53 4.5252-26 TG-1 TIE TO SB-1 CDD 31 0.764 500 1 0.7 1.53 4.5252-21 TG-1 I/C FROM TG CDG 31 0.612 600 1 0.85 1.02 6

Fault at PMCC-1 (433V)



9


Primary Current in


(Sec)

452-14 PMCC-5 I/C FROM TR-5 CDG 31 34.645 3000 1 0.15 11.55 0.19252-13 SB-3 OG TO TR-5 TJM 10 1.364 125 1 0.1 10.91 0.31252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 1.364 400 1 0.3 3.41 2.6252-1 SB-1 I/C OF SB-1 TJM 10 0.757 800 1 0.4 0.95 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.076 75 1 0.85 1.01 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.757 500 1 0.7 1.51 4.5252-26 TG-1 TIE TO SB-1 CDD 31 0.757 500 1 0.7 1.51 4.5252-21 TG-1 I/C FROM TG CDG 31 0.606 600 1 0.85 1.01 6

452-20 PMCC-6 I/C FROM TR-6 CDG 31 8.736 600 1 0.15 14.56 0.15252-20 SB-4 OG TO TR-6 TJM 10 0.344 25 1 0.1 13.75 0.29252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 0.344 500 1 0.3 0.69 Infinity252-1 SB-1 I/C OF SB-1 TJM 10 0.191 800 1 0.4 0.24 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.019 75 1 0.85 0.25 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.153 500 1 0.7 0.31 Infinity


452-19 PMCC-7 I/C FROM TR-7 CDG 31 28.205 2500 1 0.15 11.28 0.18252-19 SB-4 OG TO TR-7 TJM 10 1.110 100 1 0.1 11.10 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 1.110 500 1 0.3 2.22 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 0.617 800 1 0.4 0.77 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 1 0.85 0.82 252-3 SB-1 TIE TO TG-1 SG CDD 31 0.494 500 1 0.7 0.99 Infinity





10


Primary Current in


(Sec)

452-18 PMCC-8 I/C FROM TR-8 CDG 31 29.130 2500 1 0.15 11.65 0.18252-18 SB-4 OG TO TR-7 TJM 10 1.147 100 1 0.1 11.47 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 1.147 500 1 0.3 2.29 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 0.617 800 1 0.4 0.77 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 1 0.85 0.82 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.530 500 1 0.7 1.06 Infinity


452-17 PMCC-9 I/C FROM TR-9 CDG 31 28.431 2500 1 0.15 11.37 0.18252-17 SB-4 OG TO TR-7 TJM 10 1.119 100 1 0.1 11.19 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 1.119 500 1 0.3 2.24 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 0.621 800 1 0.4 0.78 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 1 0.85 0.83 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.498 500 1 0.7 1.00 Infinity


452-16 DCD-10 I/C FROM TR-10 CDG 31 28.243 2500 1 0.15 11.30 0.18252-16 SB-4 OG TO TR-10 TJM 10 1.112 100 1 0.1 11.12 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 1.112 500 1 0.3 2.22 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 0.617 800 1 0.4 0.77 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 1 0.85 0.82 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.494 500 1 0.7 0.99 Infinity



Fault at DCD 10 (433V)


11


Primary Current in


(Sec)

452-15 DCD-11 I/C FROM TR-11 CDG 31 28.393 2500 1 0.15 11.36 0.18252-15 SB-4 OG TO TR-11 TJM 10 1.118 100 1 0.1 11.18 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 1.118 500 1 0.3 2.24 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 0.621 800 1 0.4 0.78 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 1 0.85 0.83 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 0.497 500 1 0.7 0.99 Infinity



12


Primary Current in

CT(A)PS TMS I//Ipu Tripping

Time (Sec)

1 SB-1 OG TO SB-2 TJM 10 9.836 150 1 0.5 65.57 1.22 SB-1 I/C FOR SB-1 TJM 10 5.462 800 0.75 0.7 9.10 2.13 SB-1 I/C FROM 110kV Line ICM 21 0.546 75 0.75 0.8 9.71 2.44 SB-1 TIE TO TG-1 SG CDD 31 4.374 500 1.25 0.95 7.00 1.35 TG-1 TIE TO SB-1 CDD 31 4.374 500 1 0.65 8.75 0.846 TG-1 I/C FROM TG CDG 31 4.374 600 1 0.4 7.29 0.58

1 SB-2 OG TO TR-1 NO RELAY2 SB-2 I/C FROM SB-1 TJM 10 9.836 150 0.5 0.5 131.14 13 SB-1 OG TO SB-2 TJM 10 9.836 150 1 0.5 65.57 1.24 SB-1 I/C FOR SB-1 TJM 10 5.462 800 0.75 0.7 9.10 2.15 SB-1 I/C FROM 110kV Line ICM 21 0.546 75 0.75 0.8 9.71 2.46 SB-1 TIE TO TG-1 SG CDD 31 4.374 500 1.25 0.95 7.00 1.37 TG-1 TIE TO SB-1 CDD 31 4.374 500 1 0.65 8.75 0.848 TG-1 I/C FROM TG CDG 31 4.374 600 1 0.4 7.29 0.58

1 SB-3 OG TO TR-2 TJM 10 9.836 100 0.5 0.4 196.71 0.752 SB-3 I/C FROM SB-1 NO RELAY3 SB-1 OG TO SB-3 TJM 10 9.836 400 1 0.6 24.59 1.254 SB-1 I/C FOR SB-1 TJM 10 5.462 800 0.75 0.7 9.10 2.25 SB-1 I/C FROM 110kV Line ICM 21 0.546 75 0.75 0.8 9.71 2.46 SB-1 TIE TO TG-1 SG CDD 31 4.374 500 1.25 0.95 7.00 1.457 TG-1 TIE TO SB-1 CDD 31 4.374 500 1 0.65 8.75 0.828 TG-1 I/C FROM TG CDG 31 4.374 600 1 0.4 7.29 0.58

1 SB-4 OG TO TR-11 TJM 10 9.836 100 0.75 0.5 131.14 12 SB-3 I/C FROM SB-1 NO RELAY3 SB-1 OG TO SB-4 TJM 10 9.836 500 1 0.7 19.67 1.74 SB-1 I/C FOR SB-1 TJM 10 5.462 800 0.75 0.7 9.10 2.1

3.1.3. Existing Relay Settings for Over Current

Fault at SB-4 (11kV)





Primary Current in


Time (Sec)

5 SB-1 I/C FROM 110kV Line ICM 21 0.546 75 0.75 0.8 9.71 2.46 SB-1 TIE TO TG-1 SG CDD 31 4.374 500 1.25 0.95 7.00 1.457 TG-1 TIE TO SB-1 CDD 31 4.374 500 1 0.65 8.75 0.828 TG-1 I/C FROM TG CDG 31 4.374 600 1 0.4 7.29 0.58

1 TG-1 OG TO AUX.TR-3 CDG 31 9.836 200 1 0.55 49.18 0.552 TG-1 I/C FROM TG CDG 31 4.374 600 1 0.4 9.10 2.33 SB-1 I/C FOR SB-1 TJM 10 5.462 800 0.75 0.7 9.10 2.14 SB-1 I/C FROM 110kV Line ICM 21 0.546 75 0.75 0.8 9.71 2.45 SB-1 TIE TO TG-1 SG CDD 31 5.462 500 1.25 0.95 8.74 1.36 TG-1 TIE TO SB-1 CDD 31 5.462 500 1 0.65 10.92 0.84

1 SB-5 I/C FROM TR-2 TJM 10 3.478 200 1 0.3 17.39 0.751 SB-3 OG TO TR-2 TJM 10 0.948 100 0.5 0.4 18.97 0.852 SB-3 I/C FROM SB-1 NO RELAY3 SB-1 OG TO SB-3 TJM 10 0.948 400 1 0.6 2.37 4.54 SB-1 I/C FOR SB-1 TJM 10 0.527 800 0.75 0.7 0.88 Infinity5 SB-1 I/C FROM 110kV Line ICM 21 0.053 75 0.75 0.8 0.94 Infinity6 SB-1 TIE TO TG-1 SG CDD 31 0.422 500 1.25 0.95 0.67 Infinity7 TG-1 TIE TO SB-1 CDD 31 0.422 500 1 0.65 0.84 Infinity8 TG-1 I/C FROM TG CDG 31 0.422 600 1 0.4 0.70 Infinity

1 SB-4 I/C FROM AUX.TR-2 CDG 31 29.411 3000 1 0.15 9.80 12 SB-3 OG TO AUX.TR-2 CDG 31 1.110 200 1 0.5 5.55 0.793 SB-1 I/C FROM TG CDG 31 0.493 600 1 0.4 0.82 Infinity4 SB-1 I/C FOR SB-1 TJM 10 0.616 800 0.75 0.7 1.03 205 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 0.75 0.8 1.10 Infinity6 SB-1 TIE TO TG-1 SG CDD 31 0.616 500 1.25 0.95 0.99 67 TG-1 TIE TO SB-1 CDD 31 0.616 500 1 0.65 1.23 4

Fault at SB-5 (3kV)




Primary Current in


Time (Sec)

1 SB-6 I/C FROM AUX.TR-3 CDG 31 5.583 500 1 0.15 11.17 0.182 SB-1 OG TO AUX.TR-3 CDG 31 5.583 200 1 0.55 27.92 1.83 SB-1 I/C FROM TG CDG 31 0.745 600 1 0.4 1.24 2.34 SB-1 I/C FOR SB-1 TJM 10 0.930 800 0.75 0.7 1.55 135 SB-1 I/C FROM 110kV Line ICM 21 0.310 75 0.75 0.8 5.51 3.26 SB-1 TIE TO TG-1 SG CDD 31 0.930 500 1.25 0.95 1.49 57 TG-1 TIE TO SB-1 CDD 31 0.930 500 1 0.65 1.86 2.5

1 PMCC1 I/C FROM SB2 CDG 31 39.997 4000 0.5 0.3 20.00 0.312 SB-2 I/C FROM SB-1 TJM 10 1.574 150 0.5 0.5 20.99 13 SB-1 OG TO SB-2 TJM 10 1.574 150 1 0.5 10.50 1.24 SB-1 I/C FOR SB-1 TJM 10 0.874 800 0.75 0.7 1.46 2.15 SB-1 I/C FROM 110kV Line ICM 21 0.087 75 0.75 0.8 1.55 2.46 SB-1 TIE TO TG-1 SG CDD 31 0.700 500 1.25 0.95 1.12 1.37 TG-1 TIE TO SB-1 CDD 31 0.700 500 1 0.65 1.40 0.848 TG-1 I/C FROM TG CDG 31 0.700 600 1 0.4 1.17 0.58

1 PMCC3 I/C FROM SB2 CDG 31 34.781 3000 1 0.4 11.59 0.482 SB-3 OG TO TR-3 TJM 10 1.369 125 1 0.5 10.95 1.53 SB-3 I/C FROM SB1 NO RELAY 1.3694 SB-1 OG TO SB-3 TJM 10 1.369 400 1 0.5 3.42 2.75 SB-1 I/C OF SB-1 TJM 10 0.760 800 0.75 0.7 1.27 176 SB-1 I/C FROM 110kV Line ICM 21 0.076 75 0.75 0.8 1.35 127 SB-1 TIE TO TG-1 SG CDD 31 0.609 500 1.25 0.95 0.97 188 TG-1 TIE TO SB-1 CDD 31 0.609 500 1 0.65 1.22 89 TG-1 I/C FROM TG CDG 31 0.609 600 1 0.4 1.01 2.5

1 PMCC4 I/C FROM TR-4 CDG 31 34.963 3000 1 0.4 11.65 0.52 SB-3 OG TO TR-4 TJM 10 1.376 125 1 0.5 11.01 1.53 SB-3 I/C FROM SB-1 NO RELAY

Fault at SB-6 (3.3kV)





Primary Current in


Time (Sec)

4 SB-1 OG TO SB-3 TJM 10 1.376 400 1 0.5 3.44 2.75 SB-1 I/C OF SB-1 TJM 10 0.764 800 0.75 0.7 1.27 176 SB-1 I/C FROM 110kV Line ICM 21 0.076 75 0.75 0.8 1.36 127 SB-1 TIE TO TG-1 SG CDD 31 0.764 500 1.25 0.95 1.22 188 TG-1 TIE TO SB-1 CDD 31 0.764 500 1 0.65 1.53 89 TG-1 I/C FROM TG CDG 31 0.612 600 1 0.4 1.02 2.5

1 PMCC-5 I/C FROM TR-5 CDG 31 34.645 3000 1 0.4 11.55 0.52 SB-3 OG TO TR-5 TJM 10 1.364 125 1 0.5 10.91 1.53 SB-3 I/C FROM SB-1 NO RELAY4 SB-1 OG TO SB-3 TJM 10 1.364 400 1 0.5 3.41 2.75 SB-1 I/C OF SB-1 TJM 10 0.757 800 0.75 0.7 1.26 176 SB-1 I/C FROM 110kV Line ICM 21 0.076 75 0.75 0.8 1.35 127 SB-1 TIE TO TG-1 SG CDD 31 0.757 500 1.25 0.95 1.21 188 TG-1 TIE TO SB-1 CDD 31 0.757 500 1 0.65 1.51 89 TG-1 I/C FROM TG CDG 31 0.606 600 1 0.4 1.01 2.5

1 PMCC-6 I/C FROM TR-6 CDG 31 8.736 600 1 0.3 14.56 0.352 SB-4 OG TO TR-6 TJM 10 0.344 25 0.5 0.5 27.51 1.13 SB-4 I/C FROM SB-1 NO RELAY4 SB-1 OG TO SB-4 TJM 10 0.344 500 1 0.7 0.69 Infinity5 SB-1 I/C OF SB-1 TJM 10 0.191 800 0.75 0.7 0.32 Infinity6 SB-1 I/C FROM 110kV Line ICM 21 0.019 75 0.75 0.8 0.34 Infinity7 SB-1 TIE TO TG-1 SG CDD 31 0.153 500 1.25 0.95 0.24 Infinity8 TG-1 TIE TO SB-1 CDD 31 0.153 500 1 0.65 0.31 Infinity9 TG-1 I/C FROM TG CDG 31 0.153 600 1 0.4 0.25 Infinity

1 PMCC-7 I/C FROM TR-7 CDG 31 28.205 2500 1 0.4 11.28 0.512 SB-4 OG TO TR-7 TJM 10 1.110 100 1 0.5 11.10 1.53 SB-4 I/C FROM SB-1 NO RELAY4 SB-1 OG TO SB-4 TJM 10 1.110 500 1 0.7 2.22 17





Primary Current in


Time (Sec)

5 SB-1 I/C FOR SB-1 TJM 10 0.617 800 0.75 0.7 1.03 Infinity6 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 0.75 0.8 1.10 Infinity7 SB-1 TIE TO TG-1 SG CDD 31 0.494 500 1.25 0.95 0.79 128 TG-1 TIE TO SB-1 CDD 31 0.494 500 1 0.65 0.99 89 TG-1 I/C FROM TG CDG 31 0.494 600 1 0.4 0.82 3

1 PMCC-8 I/C FROM TR-8 CDG 31 29.130 2500 1 0.3 11.65 0.382 SB-4 OG TO TR-7 TJM 10 1.147 100 1 0.5 11.47 1.53 SB-4 I/C FROM SB-1 NO RELAY4 SB-1 OG TO SB-4 TJM 10 1.147 500 1 0.7 2.29 175 SB-1 I/C FOR SB-1 TJM 10 0.637 800 0.75 0.7 1.06 Infinity6 SB-1 I/C FROM 110kV Line ICM 21 0.064 75 0.75 0.8 1.13 Infinity7 SB-1 TIE TO TG-1 SG CDD 31 0.510 500 1.25 0.95 0.82 18 TG-1 TIE TO SB-1 CDD 31 0.510 500 1 0.65 1.02 89 TG-1 I/C FROM TG CDG 31 0.510 600 1 0.4 0.85 3

1 PMCC-9 I/C FROM TR-9 CDG 31 28.431 2500 0.5 0.75 22.74 0.752 SB-4 OG TO TR-7 TJM 10 1.119 100 0.75 0.6 14.92 1.73 SB-4 I/C FROM SB-1 NO RELAY4 SB-1 OG TO SB-4 TJM 10 1.119 500 1 0.7 2.24 175 SB-1 I/C FOR SB-1 TJM 10 0.621 800 0.75 0.7 1.04 Infinity6 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 0.75 0.8 1.10 Infinity7 SB-1 TIE TO TG-1 SG CDD 31 0.498 500 1.25 0.95 0.80 Infinity8 TG-1 TIE TO SB-1 CDD 31 0.498 500 1 0.65 1.00 89 TG-1 I/C FROM TG CDG 31 0.498 600 1 0.4 0.83 3

1 DCD-10 I/C FROM TR-10 CDG 31 28.243 2500 0.75 0.3 15.06 0.352 SB-4 OG TO TR-10 TJM 10 1.112 100 0.75 0.5 14.82 1.43 SB-4 I/C FROM SB-1 NO RELAY4 SB-1 OG TO SB-4 TJM 10 1.112 500 1 0.7 2.22 175 SB-1 I/C FOR SB-1 TJM 10 0.617 800 0.75 0.7 1.03 Infinity





Primary Current in


Time (Sec)

6 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 0.75 0.8 1.10 Infinity7 SB-1 TIE TO TG-1 SG CDD 31 0.494 500 1.25 0.95 0.79 Infinity8 TG-1 TIE TO SB-1 CDD 31 0.494 500 1 0.65 0.99 89 TG-1 I/C FROM TG CDG 31 0.494 600 1 0.4 0.82 3

1 DCD-11 I/C FROM TR-11 CDG 31 28.393 2500 0.75 0.2 15.14 0.232 SB-4 OG TO TR-11 TJM 10 1.118 100 0.75 0.5 14.90 1.43 SB-4 I/C FROM SB-1 NO RELAY4 SB-1 OG TO SB-4 TJM 10 1.118 500 1 0.7 2.24 175 SB-1 I/C FOR SB-1 TJM 10 0.621 800 0.75 0.7 1.03 Infinity6 SB-1 I/C FROM 110kV Line ICM 21 0.062 75 0.75 0.8 1.10 Infinity7 SB-1 TIE TO TG-1 SG CDD 31 0.497 500 1.25 0.95 0.80 Infinity8 TG-1 TIE TO SB-1 CDD 31 0.497 500 1 0.65 0.99 89 TG-1 I/C FROM TG CDG 31 0.497 600 1 0.4 0.83 3


S.No SB No Description Relay Type Fault Current in A

Primary Current in


Time (Sec)

252-2 SB-1 OG TO SB-2 TJM 10 100 150 0.3 0.1 2.22 0.75252-1 SB-1 I/C FOR SB-1 MIT 161 100 800 0.075 0.15 1.67 2.05

SB-1 GT T/F NUTRAL MIT 161 100 100 0.6 0.15 1.67 2.05152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.75 0.2 1.78 2.30252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.1 0.15 2.00 1.51252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.1 0.15 2.00 1.51252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.4 1.67 1.80

252-8 SB-2 OG TO TR-1 NO RELAY252-7 SB-2 I/C FROM SB-1 TJM 10 100 150 0.3 0.1 2.22 0.75252-2 SB-1 OG TO SB-2 TJM 10 100 150 0.3 0.1 2.22 0.75252-1 SB-1 I/C FOR SB-1 MIT 161 100 800 0.075 0.15 1.67 2.05152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.75 0.2 1.78 2.30252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.1 0.15 2.00 1.51252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.1 0.15 2.00 1.51252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.45 1.67 1.80

252-10 SB-3 OG TO TR-2 TJM 10 100 100 0.5 0.1 2.00 0.90252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 MIT 161 100 400 0.125 0.125 2.00 1.25252-1 SB-1 I/C FOR SB-1 MIT 161 100 800 0.075 0.15 1.67 2.05152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.75 0.2 1.78 2.30252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.1 0.15 2.00 1.51252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.1 0.15 2.00 1.51


3.2. Earth Fault Relay Settings3.2.1 Recommended Earth Fault Relay Settings




Primary Current in


Time (Sec)

252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.45 1.67 1.80

252-15 SB-4 OG TO TR-11 TJM 10 100 200 0.25 0.1 2.00 0.90252-14 SB-3 I/C FROM SB-1 NO RELAY252-5 SB-1 OG TO SB-4 MIT 161 100 500 0.1 0.125 2.00 1.25252-1 SB-1 I/C FOR SB-1 MIT 161 100 800 0.075 0.15 1.67 2.05152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.75 0.2 1.78 2.30252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.1 0.15 2.00 1.51252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.1 0.15 2.00 1.51252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.45 1.67 1.80

252-25 TG-1 OG TO AUX.TR-3 CDG 31 100 200 0.25 0.3 2.00 0.92252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.45 1.67 1.80252-1 SB-1 I/C FOR SB-1 MIT 161 100 800 0.075 0.15 1.67 2.05152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.75 0.2 1.78 2.30252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.1 0.15 2.00 1.51252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.1 0.15 2.00 1.51

352-1 SB-5 I/C FROM TR-2 TJM 10 100 200 0.25 0.1 2.00 0.90SB-5 TR-2 NUTRAL MIT 161 100 200 0.25 0.1 2.00 1.00

252-10 SB-3 OG TO TR-2 TJM 10 100 100 0.5 0.1 2.00 0.90252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 MIT 161 100 400 0.125 0.125 2.00 1.25252-1 SB-1 I/C FOR SB-1 MIT 161 100 800 0.075 0.15 1.67 2.05152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.75 0.2 1.78 2.30252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.1 0.15 2.00 1.51252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.1 0.15 2.00 1.51252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.45 1.67 1.80



Fault at SB-5 (3kV)


Primary Current in


Time (Sec)

352-2 SB-6 I/C FROM AUX.TR-3 CDG 31 100 500 0.1 0.1 2.00 0.26SB-6 AUX.TR NUTRAL MIT 161 100 500 0.1 0.075 2.00 0.75

252-25 SB-1 OG TO AUX.TR-3 CDG 31 100 200 0.25 0.3 2.00 0.92252-21 SB-1 I/C FROM TG CDG 31 100 600 0.1 0.45 1.67 1.80252-1 SB-1 I/C FOR SB-1 MIT 161 100 800 0.075 0.15 1.67 2.05152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.75 0.2 1.78 2.30252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.1 0.15 2.00 1.51252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.1 0.15 2.00 1.51

452-2 PMCC-2 I/C FROM AUX.TR-2 CDG 31 551 3000 0.1 0.1 1.84 0.29PMCC-2 AUX.TR NUTRAL MIT 161 551 3000 0.1 0.075 1.84 0.86

252-23 TG-1 OG TO AUX.TR-2 CDG 31 21.69 200 0.25 0.3 0.43 INFINITY252-21 TG-1 I/C FROM TG CDG 31 21.69 600 0.1 0.45 0.36 INFINITY252-1 SB-1 I/C FOR SB-1 MIT 161 21.69 800 0.075 0.15 0.36 INFINITY152-1 SB-1 I/C FROM 110kV Line ICM 21 21.69 75 0.75 0.2 0.39 INFINITY252-3 SB-1 TIE TO TG-1 SG MIT 161 21.69 500 0.1 0.15 0.43 INFINITY252-26 TG-1 TIE TO SB-1 MIT 161 21.69 500 0.1 0.15 0.43 INFINITY

452-11 PMCC1 I/C FROM SB2 CDG 31 750 4000 0.1 0.1 1.88 0.29PMCC1 TR-1 NUTRAL MIT 161 750 4000 0.1 0.075 1.88 0.83

252-8 SB-2 OG TO SB-2 NO RELAY252-7 SB-2 I/C FROM SB-1 TJM 10 29.52 150 0.3 0.1 0.66 INFINITY252-2 SB-1 OG TO SB-2 TJM 10 29.52 150 0.3 0.1 0.66 INFINITY252-1 SB-1 I/C FOR SB-1 MIT 161 29.52 800 0.075 0.15 0.49 INFINITY152-1 SB-1 I/C FROM 110kV Line ICM 21 29.52 75 0.75 0.2 0.52 INFINITY252-3 SB-1 TIE TO TG-1 SG MIT 161 29.52 500 0.1 0.15 0.59 INFINITY252-26 TG-1 TIE TO SB-1 MIT 161 29.52 500 0.1 0.15 0.59 INFINITY

Fault at TG PMCC-3(3.3kV)




Primary Current in


Time (Sec)

252-21 TG-1 I/C FROM TG CDG 31 29.52 600 0.1 0.45 0.49 INFINITY

252-12 PMCC3 I/C FROM SB-3 CDG 31 652 3000 0.1 0.1 2.17 0.25PMCC3 TR-3 NUTRAL MIT 161 652 3000 0.1 0.075 2.17 0.67

252-11 SB-3 OG TO TR-3 TJM 10 25.67 125 0.4 0.1 0.51 INFINITY252-9 SB-3 I/C FROM SB1 NO RELAY 25.67252-4 SB-1 OG TO SB-3 MIT 161 25.67 400 0.125 0.125 0.51 INFINITY252-1 SB-1 I/C OF SB-1 MIT 161 25.67 800 0.075 0.15 0.43 INFINITY152-1 SB-1 I/C FROM 110kV Line ICM 21 25.67 75 0.75 0.2 0.46 INFINITY252-3 SB-1 TIE TO TG-1 SG MIT 161 25.67 500 0.1 0.15 0.51 INFINITY252-26 TG-1 TIE TO SB-1 MIT 161 25.67 500 0.1 0.15 0.51 INFINITY252-21 TG-1 I/C FROM TG CDG 31 25.67 600 0.1 0.45 0.43 INFINITY

452-13 PMCC4 I/C FROM TR-4 CDG 31 656 3000 0.1 0.1 2.19 0.24PMCC4 TR-4 NUTRAL MIT 161 656 3000 0.1 0.075 2.19 0.67

252-12 SB-3 OG TO TR-4 TJM 10 25.80 125 0.4 0.1 0.52 INFINITY252-9 SB-3 I/C FROM SB-1 NO RELAY 25.80252-4 SB-1 OG TO SB-3 MIT 161 25.80 400 0.125 0.125 0.52 INFINITY252-1 SB-1 I/C OF SB-1 MIT 161 25.80 800 0.075 0.15 0.43 INFINITY152-1 SB-1 I/C FROM 110kV Line ICM 21 25.80 75 0.75 0.2 0.46 INFINITY252-3 SB-1 TIE TO TG-1 SG MIT 161 25.80 500 0.1 0.15 0.52 INFINITY252-26 TG-1 TIE TO SB-1 MIT 161 25.80 500 0.1 0.15 0.52 INFINITY252-21 TG-1 I/C FROM TG CDG 31 25.80 600 0.1 0.45 0.43 INFINITY

452-14 PMCC-5 I/C FROM TR-5 CDG 31 650 3000 0.1 0.1 2.17 0.25PMCC-5 TR-5 NUTRAL MIT 161 649.56 3000 0.1 0.075 2.17 0.68

252-13 SB-3 OG TO TR-5 TJM 10 25.57 125 0.4 0.1 0.51 INFINITY252-9 SB-3 I/C FROM SB-1 NO RELAY 25.57





Primary Current in


Time (Sec)

252-4 SB-1 OG TO SB-3 MIT 161 25.57 400 0.125 0.125 0.51 INFINITY252-1 SB-1 I/C OF SB-1 MIT 161 25.57 800 0.075 0.15 0.43 INFINITY152-1 SB-1 I/C FROM 110kV Line ICM 21 25.57 75 0.75 0.2 0.45 INFINITY252-3 SB-1 TIE TO TG-1 SG MIT 161 25.57 500 0.1 0.15 0.51 INFINITY252-26 TG-1 TIE TO SB-1 MIT 161 25.57 500 0.1 0.15 0.51 INFINITY252-21 TG-1 I/C FROM TG CDG 31 25.57 600 0.1 0.45 0.43 INFINITY

452-20 PMCC-6 I/C FROM TR-6 CDG 31 164 600 0.1 0.1 2.73 0.20PMCC-6 TR-6 NUTRAL MIT 161 164 600 0.1 0.075 2.73 0.52

252-20 SB-4 OG TO TR-6 TJM 10 6.45 25 2 0.1 0.13 INFINITY252-9 SB-4 I/C FROM SB-1 NO RELAY 6.45252-4 SB-1 OG TO SB-4 MIT 161 6.45 500 0.1 0.125 0.13 INFINITY252-1 SB-1 I/C OF SB-1 MIT 161 6.45 800 0.075 0.15 0.11 INFINITY152-1 SB-1 I/C FROM 110kV Line ICM 21 6.45 75 0.75 0.2 0.11 INFINITY252-3 SB-1 TIE TO TG-1 SG MIT 161 6.45 500 0.1 0.15 0.13 INFINITY252-26 TG-1 TIE TO SB-1 MIT 161 6.45 500 0.1 0.15 0.13 INFINITY252-21 TG-1 I/C FROM TG CDG 31 6.45 600 0.1 0.45 0.11 INFINITY


252-19 SB-4 OG TO TR-7 TJM 10 20.82 100 0.5 0.1 0.42 INFINITY252-9 SB-4 I/C FROM SB-1 NO RELAY 20.82252-4 SB-1 OG TO SB-4 MIT 161 20.82 500 0.1 0.125 0.42 INFINITY252-1 SB-1 I/C FOR SB-1 MIT 161 20.82 800 0.075 0.15 0.35 INFINITY152-1 SB-1 I/C FROM 110kV Line ICM 21 20.82 75 0.75 0.2 0.37 INFINITY252-3 SB-1 TIE TO TG-1 SG MIT 161 20.82 500 0.1 0.15 0.42 INFINITY252-26 TG-1 TIE TO SB-1 MIT 161 20.82 500 0.1 0.15 0.42 INFINITY252-21 TG-1 I/C FROM TG CDG 31 20.82 600 0.1 0.45 0.35 INFINITY




Primary Current in


Time (Sec)





452-16 DCD-10 I/C FROM TR-10 CDG 31 530 2500 0.1 0.1 2.12 0.26DCD-10 TR-10 NUTRAL MIT 161 530 2500 0.1 0.075 2.12 0.70

252-16 SB-4 OG TO TR-10 TJM 10 20.84 100 0.5 0.1 0.42 INFINITY252-9 SB-4 I/C FROM SB-1 NO RELAY 20.84





Primary Current in


Time (Sec)

252-4 SB-1 OG TO SB-4 MIT 161 20.84 500 0.1 0.125 0.42 INFINITY252-1 SB-1 I/C FOR SB-1 MIT 161 20.84 800 0.075 0.15 0.35 INFINITY152-1 SB-1 I/C FROM 110kV Line ICM 21 20.84 75 0.75 0.2 0.37 INFINITY252-3 SB-1 TIE TO TG-1 SG MIT 161 20.84 500 0.1 0.15 0.42 INFINITY252-26 TG-1 TIE TO SB-1 MIT 161 20.84 500 0.1 0.15 0.42 INFINITY252-21 TG-1 I/C FROM TG CDG 31 20.84 600 0.1 0.45 0.35 INFINITY

452-15 DCD-11 I/C FROM TR-11 CDG 31 532 2500 0.1 0.1 2.13 0.26DCD-11 TR-11 NUTRAL MIT 161 532 2500 0.1 0.075 2.13 0.69

252-15 SB-4 OG TO TR-11 TJM 10 20.94 100 0.5 0.1 0.42 INFINITY252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 MIT 161 20.94 500 0.1 0.125 0.42 INFINITY252-1 SB-1 I/C FOR SB-1 MIT 161 20.94 800 0.075 0.15 0.35 INFINITY152-1 SB-1 I/C FROM 110kV Line ICM 21 20.94 75 0.75 0.2 0.37 INFINITY252-3 SB-1 TIE TO TG-1 SG MIT 161 20.94 500 0.1 0.15 0.42 INFINITY252-26 TG-1 TIE TO SB-1 MIT 161 20.94 500 0.1 0.15 0.42 INFINITY252-21 TG-1 I/C FROM TG CDG 31 20.94 600 0.1 0.45 0.35 INFINITY

Recommended relays and settings



Primary Current in


Time (Sec)

252-2 SB-1 OG TO SB-2 TJM 10 100 150 0.1 0.2 6.67 0.75252-1 SB-1 I/C FOR SB-1 TJM 10 100 800 0.2 0.2 0.63 7152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.1 0.1 13.33 0.23252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.005 0.7 40.00 1.28252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.005 0.25 40.00 0.458252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.3 1.67 1.1

252-8 SB-2 OG TO TR-1 NO RELAY 100252-7 SB-2 I/C FROM SB-1 TJM 10 100 150 0.1 0.5 6.67 1.7252-2 SB-1 OG TO SB-2 TJM 10 100 150 0.1 0.2 6.67 0.75252-1 SB-1 I/C FOR SB-1 TJM 10 100 800 0.2 0.2 0.63 7152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.1 0.1 13.33 0.23252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.005 0.7 40.00 1.28252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.005 0.25 40.00 0.458252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.3 1.67 1.1

252-10 SB-3 OG TO TR-2 TJM 10 100 100 0.1 0.1 10.00 0.31252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 100 400 0.1 0.15 2.50 1252-1 SB-1 I/C FOR SB-1 TJM 10 100 800 0.2 0.2 0.63 7152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.1 0.1 13.33 0.27252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.005 0.7 40.00 1.28252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.005 0.25 40.00 0.458252-21 TG-1 I/C FROM TG CDG 31 100 200 0.1 0.3 5.00 0.5

252-15 SB-4 OG TO TR-11 TJM 10 100 100 0.2 0.5 5.00 0.43252-14 SB-3 I/C FROM SB-1 NO RELAY252-5 SB-1 OG TO SB-4 TJM 10 100 500 0.2 0.8 1.00 20252-1 SB-1 I/C FOR SB-1 TJM 10 100 800 0.2 0.2 0.63 7

3.2.2. Existing Earth Fault Relay Settings






Primary Current in


Time (Sec)

152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.1 0.1 13.33 0.27252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.005 0.7 40.00 1.28252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.005 0.25 40.00 0.458252-21 TG-1 I/C FROM TG CDG 31 100 200 0.1 0.3 5.00 0.5

252-25 TG-1 OG TO AUX.TR-3 CDG 31 100 200 0.1 0.1 5.00 0.43252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.3 1.67 1.1252-1 SB-1 I/C FOR SB-1 TJM 10 100 800 0.2 0.2 0.63 7152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.1 0.1 13.33 0.27252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.005 0.7 40.00 1.28252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.005 0.25 40.00 0.458

352-1 SB-5 I/C FROM TR-2 TJM 10 100 200 0.1 0.1 5.00 0.43252-10 SB-3 OG TO TR-2 TJM 10 100 100 0.1 0.1 10.00 0.31252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 100 400 0.1 0.15 2.50 1252-1 SB-1 I/C FOR SB-1 TJM 10 100 800 0.2 0.2 0.63 7152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.1 0.1 13.33 0.27252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.005 0.7 40.00 1.28252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.005 0.25 40.00 0.458252-21 TG-1 I/C FROM TG CDG 31 100 600 0.1 0.3 1.67 1.1

352-2 SB-6 I/C FROM AUX.TR-3 CDG 31 100 500 0.1 0.1 2.00 0.26252-25 SB-1 OG TO AUX.TR-3 CDG 31 100 200 0.1 0.1 5.00 0.16252-21 SB-1 I/C FROM TG CDG 31 100 600 0.1 0.3 1.67 1.1252-1 SB-1 I/C FOR SB-1 TJM 10 100 800 0.2 0.2 0.63 7152-1 SB-1 I/C FROM 110kV Line ICM 21 100 75 0.1 0.1 13.33 0.27252-3 SB-1 TIE TO TG-1 SG MIT 161 100 500 0.005 0.7 40.00 1.28252-26 TG-1 TIE TO SB-1 MIT 161 100 500 0.005 0.25 40.00 0.458

Fault at SB-5 (3kV)

Fault at TG -PMCC-3 (3.3kV)



Primary Current in


Time (Sec)

452-1 SB-4 I/C FROM AUX.TR-2 CDG 31 551 3000 0.1 0.1 1.84 0.28252-23 SB-3 OG TO AUX.TR-2 CDG 31 21.69 200 0.1 0.1 1.08 Infinity252-21 SB-1 I/C FROM TG CDG 31 21.69 600 0.1 0.3 0.36 Infinity252-1 SB-1 I/C FOR SB-1 TJM 10 21.69 800 0.2 0.2 0.14 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 21.69 75 0.1 0.1 2.89 0.55252-3 SB-1 TIE TO TG-1 SG MIT 161 21.69 500 0.005 0.7 8.68 2.22252-26 TG-1 TIE TO SB-1 MIT 161 21.69 500 0.005 0.25 8.68 0.793

452-11 PMCC1 I/C FROM SB2 CDG 31 750 4000 0.1 0.1 1.88 0.3252-7 SB-2 I/C FROM SB-1 TJM 10 29.52 150 0.1 0.5 1.97 1.7252-2 SB-1 OG TO SB-2 TJM 10 29.52 150 0.1 0.2 1.97 1.7252-1 SB-1 I/C FOR SB-1 TJM 10 29.52 800 0.2 0.2 0.18 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 29.52 75 0.1 0.1 3.94 0.45252-3 SB-1 TIE TO TG-1 SG MIT 161 29.52 500 0.005 0.7 11.81 1.937252-26 TG-1 TIE TO SB-1 MIT 161 29.52 500 0.005 0.25 11.81 0.692252-21 TG-1 I/C FROM TG CDG 31 29.52 600 0.1 0.3 0.49 Infinity

452-12 PMCC3 I/C FROM SB-3 CDG 31 652 3000 0.1 0.2 2.17 0.55252-11 SB-3 OG TO TR-3 TJM 10 25.67 125 0.1 0.2 2.05 1.7252-9 SB-3 I/C FROM SB1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 25.67 400 0.1 0.15 0.64 Infinity252-1 SB-1 I/C OF SB-1 TJM 10 25.67 800 0.2 0.2 0.16 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 25.67 75 0.1 0.1 3.42 0.5252-3 SB-1 TIE TO TG-1 SG MIT 161 25.67 500 0.005 0.7 10.27 2.056252-26 TG-1 TIE TO SB-1 MIT 161 25.67 500 0.005 0.25 10.27 0.735252-21 TG-1 I/C FROM TG CDG 31 25.67 600 0.1 0.3 0.43 Infinity

452-13 PMCC4 I/C FROM TR-4 CDG 31 656 3000 0.1 0.1 2.19 0.27252-12 SB-3 OG TO TR-4 TJM 10 25.80 125 0.1 0.2 2.06 1.7






Primary Current in


Time (Sec)

252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 25.80 400 0.1 0.15 0.65 Infinity252-1 SB-1 I/C OF SB-1 TJM 10 25.80 800 0.2 0.2 0.16 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 25.80 75 0.1 0.1 3.44 0.5252-3 SB-1 TIE TO TG-1 SG MIT 161 25.80 500 0.005 0.7 10.32 2.051252-26 TG-1 TIE TO SB-1 MIT 161 25.80 500 0.005 0.25 10.32 0.733252-21 TG-1 I/C FROM TG CDG 31 25.80 600 0.1 0.3 0.43 Infinity

452-14 PMCC-5 I/C FROM TR-5 CDG 31 650 3000 0.1 0.15 2.17 0.4252-13 SB-3 OG TO TR-5 TJM 10 25.57 125 0.1 0.2 2.05 1.7252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 25.57 400 0.1 0.15 0.64 Infinity252-1 SB-1 I/C OF SB-1 TJM 10 25.57 800 0.2 0.2 0.16 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 25.57 75 0.1 0.1 3.41 0.5252-3 SB-1 TIE TO TG-1 SG MIT 161 25.57 500 0.005 0.7 10.23 2.059252-26 TG-1 TIE TO SB-1 MIT 161 25.57 500 0.005 0.25 10.23 0.736252-21 TG-1 I/C FROM TG CDG 31 25.57 600 0.1 0.3 0.43 Infinity

452-20 PMCC-6 I/C FROM TR-6 NO RELAY 164 - - -252-20 SB-4 OG TO TR-6 TJM 10 6.45 25 0.1 0.1 2.58 0.7252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 6.45 500 0.2 0.8 0.06 Infinity252-1 SB-1 I/C OF SB-1 TJM 10 6.45 800 0.2 0.2 0.04 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 6.45 75 0.1 0.1 0.86 Infinity252-3 SB-1 TIE TO TG-1 SG MIT 161 6.45 500 0.005 0.7 2.58 5.124252-26 TG-1 TIE TO SB-1 MIT 161 6.45 500 0.005 0.25 2.58 1.83252-21 TG-1 I/C FROM TG CDG 31 6.45 600 0.1 0.3 0.11 Infinity

452-19 PMCC-7 I/C FROM TR-7 CDG 31 529 2500 0.1 0.1 2.12 0.26252-19 SB-4 OG TO TR-7 TJM 10 20.82 100 0.1 0.2 2.08 1.7252-9 SB-4 I/C FROM SB-1 NO RELAY





Primary Current in


Time (Sec)

252-4 SB-1 OG TO SB-4 TJM 10 20.82 500 0.2 0.8 0.21 Infinity252-1 SB-1 I/C FOR SB-1 TJM 10 20.82 800 0.2 0.2 0.13 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 20.82 75 0.1 0.1 2.78 0.52252-3 SB-1 TIE TO TG-1 SG MIT 161 20.82 500 0.005 0.7 8.33 2.264252-26 TG-1 TIE TO SB-1 MIT 161 20.82 500 0.005 0.25 8.33 0.809252-21 TG-1 I/C FROM TG CDG 31 20.82 600 0.1 0.3 0.35 Infinity

452-18 PMCC-8 I/C FROM TR-8 CDG 31 546 2500 0.1 0.1 2.18 0.26252-18 SB-4 OG TO TR-7 TJM 10 21.50 100 0.1 0.2 2.15 1.68252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 21.50 500 0.2 0.8 0.21 Infinity252-1 SB-1 I/C FOR SB-1 TJM 10 21.50 800 0.2 0.2 0.13 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 21.50 75 0.1 0.1 2.87 0.45252-3 SB-1 TIE TO TG-1 SG MIT 161 21.50 500 0.005 0.7 8.60 2.229252-26 TG-1 TIE TO SB-1 MIT 161 21.50 500 0.005 0.25 8.60 0.796252-21 TG-1 I/C FROM TG CDG 31 21.50 600 0.1 0.3 0.36 Infinity

452-17 PMCC-9 I/C FROM TR-9 CDG 31 533 2500 0.1 0.1 2.13 0.26252-17 SB-4 OG TO TR-7 TJM 10 20.98 100 0.1 0.2 2.10 1.7252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 20.98 500 0.2 0.8 0.21 Infinity252-1 SB-1 I/C FOR SB-1 TJM 10 20.98 800 0.2 0.2 0.13 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 20.98 75 0.1 0.1 2.80 0.45252-3 SB-1 TIE TO TG-1 SG MIT 161 20.98 500 0.005 0.7 8.39 2.255252-26 TG-1 TIE TO SB-1 MIT 161 20.98 500 0.005 0.25 8.39 0.806252-21 TG-1 I/C FROM TG CDG 31 20.98 600 0.1 0.3 0.35 Infinity

452-16 DCD-10 I/C FROM TR-10 CDG 31 530 2500 0.4 0.5 0.53 Infinity252-16 SB-4 OG TO TR-10 TJM 10 20.84 100 0.2 0.2 1.04 Infinity252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 20.84 500 0.2 0.8 0.21 Infinity252-1 SB-1 I/C FOR SB-1 TJM 10 20.84 800 0.2 0.2 0.13 Infinity





Primary Current in


Time (Sec)

152-1 SB-1 I/C FROM 110kV Line ICM 21 20.84 75 0.1 0.1 2.78 0.45252-3 SB-1 TIE TO TG-1 SG MIT 161 20.84 500 0.005 0.7 8.34 2.262252-26 TG-1 TIE TO SB-1 MIT 161 20.84 500 0.005 0.25 8.34 0.808252-21 TG-1 I/C FROM TG CDG 31 20.84 600 0.1 0.3 0.35 Infinity

452-15 DCD-11 I/C FROM TR-11 CDG 31 532 2500 0.4 0.5 0.53 Infinity252-15 SB-4 OG TO TR-11 TJM 10 20.95 100 0.2 0.5 1.05 Infinity252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 20.95 500 0.2 0.8 0.21 Infinity252-1 SB-1 I/C FOR SB-1 TJM 10 20.94 800 0.2 0.2 0.13 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 20.94 75 0.1 0.1 2.79 0.45252-3 SB-1 TIE TO TG-1 SG MIT 161 20.94 500 0.005 0.7 8.38 2.257252-26 TG-1 TIE TO SB-1 MIT 161 20.94 500 0.005 0.25 8.38 0.806252-21 TG-1 I/C FROM TG CDG 31 20.94 600 0.1 0.3 0.35 Infinity


4. COMPARISON OF EXISTING &RECOMMENDED SETTINGS

S.No SB No Description Relay TypePrimary

Current in CT(A)

PS TMS Tripping Time (Sec) PS TMS Tripping Time

(Sec)

252-2 SB-1 OG TO SB-2 TJM 10 150 1 0.5 1.2 1 0.3 0.67252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 2.1 1 0.4 1.5152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 2.4 1 0.85 2.4252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 1.3 1 0.7 0.96252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 0.84 1 0.7 0.96252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 0.58 1 0.85 1.25

252-8 SB-2 OG TO TR-1 NO RELAY252-7 SB-2 I/C FROM SB-1 TJM 10 150 0.5 0.5 1 1 0.3 0.67252-2 SB-1 OG TO SB-2 TJM 10 150 1 0.5 1.2 1 0.3 0.67252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 2.1 1 0.4 1.5152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 2.4 1 0.85 2.4252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 1.3 1 0.7 0.96252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 0.84 1 0.7 0.96252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 0.58 1 0.85 1.2

252-10 SB-3 OG TO TR-2 TJM 10 100 0.5 0.4 0.75 0.75 0.1 0.23252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 400 1 0.6 1.25 1 0.3 0.67252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 2.2 1 0.4 1.5152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 2.4 1 0.85 2.4252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 1.45 1 0.7 0.96252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 0.82 1 0.7 0.96252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 0.58 1 0.85 1.2

252-15 SB-4 OG TO TR-11 TJM 10 100 0.75 0.5 1 1 0.1 0.23252-14 SB-3 I/C FROM SB-1 NO RELAY252-5 SB-1 OG TO SB-4 TJM 10 500 1 0.7 1.7 1 0.3 0.7252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 2.1 1 0.4 1.5152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 2.4 1 0.85 2.4252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 1.45 1 0.7 0.98

4.1. Comparison of Existing & Recommended Settings - Over Current

Existing Service Settings ELSYTEC's Recommended SettingsFault at SB-1 (11kV)





Current in CT(A)


(Sec)

Existing Service Settings ELSYTEC's Recommended Settings252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 0.82 1 0.7 0.98252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 0.58 1 0.85 1.3

252-25 TG-1 OG TO AUX.TR-3 CDG 31 200 1 0.55 0.55 1 0.3 0.31252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 2.3 1 0.85 1.15252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 2.1 1 0.4 1.5152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 2.4 1 0.85 2.4252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 1.3 1 0.7 0.88252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 0.84 1 0.7 0.88

352-1 SB-5 I/C FROM TR-2 TJM 10 200 1 0.3 0.75 1 0.1 0.26252-10 SB-3 OG TO TR-2 TJM 10 100 0.5 0.4 0.85 0.75 0.1 0.39252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 400 1 0.6 4.5 1 0.3 2.4252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 Infinity 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 Infinity 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 Infinity 1 0.7 Infinity252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 Infinity 1 0.7 Infinity252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 Infinity 1 0.85 Infinity

352-2 SB-6 I/C FROM AUX.TR-3 CDG 31 500 1 0.15 1 1 0.1 0.13252-25 TG-1 OG TO AUX.TR-3 CDG 31 200 1 0.5 0.79 1 0.3 0.42252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 Infinity 1 0.85 6252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 20 1 0.4 infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 Infinity 1 0.85 infinity252-3 TG-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 6 1 0.7 4252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 4 1 0.7 4

452-2 SB-4 I/C FROM AUX.TR-2 CDG 31 3000 1 0.15 0.18 1 0.1 0.13252-23 SB-3 OG TO AUX.TR-2 CDG 31 200 1 0.55 1.8 1 0.3 0.48252-21 SB-1 I/C FROM TG CDG 31 600 1 0.4 2.3 1 0.85 Infinity252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 13 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 3.2 1 0.85 Infinity


Fault at SB-5 (3kV)

Fault at SB-6 (3.3kV)

Fault at TG-PMCC-2 (4+A114V)


Current in CT(A)


(Sec)

Existing Service Settings ELSYTEC's Recommended Settings252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 5 1 0.7 5252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 2.5 1 0.7 5

452-11 PMCC1 I/C FROM SB2 CDG 31 4000 0.5 0.3 0.31 1 0.15 0.18252-8 SB-2 I/C FROM SB-1 TJM 10 150 0.5 0.5 1 1 0.3 0.88252-7 SB-1 OG TO SB-2 TJM 10 150 1 0.5 1.2 1 0.3 0.88252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 2.1 1 0.4 12152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 2.4 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 1.3 1 0.7 5252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 0.84 1 0.7 5252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 0.58 1 0.85 7

252-12 PMCC3 I/C FROM SB2 CDG 31 3000 1 0.4 0.48 1 0.15 0.18252-11 SB-3 OG TO TR-3 TJM 10 125 1 0.5 1.5 1 0.1 0.31252-9 SB-3 I/C FROM SB1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 400 1 0.5 2.7 1 0.3 2.6252-1 SB-1 I/C OF SB-1 TJM 10 800 0.75 0.7 17 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 12 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 18 1 0.7 4.5252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 8 1 0.7 4.5252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 2.5 1 0.85 6

452-13 PMCC4 I/C FROM TR-4 CDG 31 3000 1 0.4 0.5 1 0.15 0.18252-12 SB-3 OG TO TR-4 TJM 10 125 1 0.5 1.5 1 0.1 0.31252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 400 1 0.5 2.7 1 0.3 2.6252-1 SB-1 I/C OF SB-1 TJM 10 800 0.75 0.7 17 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 12 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 18 1 0.7 4.5252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 8 1 0.7 4.5252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 2.5 1 0.85 6





Current in CT(A)


(Sec)

Existing Service Settings ELSYTEC's Recommended Settings

452-14 PMCC-5 I/C FROM TR-5 CDG 31 3000 1 0.4 0.5 1 0.15 0.19252-13 SB-3 OG TO TR-5 TJM 10 125 1 0.5 1.5 1 0.1 0.31252-9 SB-3 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-3 TJM 10 400 1 0.5 2.7 1 0.3 2.6252-1 SB-1 I/C OF SB-1 TJM 10 800 0.75 0.7 17 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 12 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 18 1 0.7 4.5252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 8 1 0.7 4.5252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 2.5 1 0.85 6

452-20 PMCC-6 I/C FROM TR-6 CDG 31 600 1 0.3 0.35 1 0.15 0.15252-20 SB-4 OG TO TR-6 TJM 10 25 0.5 0.5 1.1 1 0.1 0.29252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 500 1 0.7 Infinity 1 0.3 Infinity252-1 SB-1 I/C OF SB-1 TJM 10 800 0.75 0.7 Infinity 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 Infinity 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 Infinity 1 0.7 Infinity252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 Infinity 1 0.7 Infinity252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 Infinity 1 0.85 Infinity

452-19 PMCC-7 I/C FROM TR-7 CDG 31 2500 1 0.4 0.51 1 0.15 0.18252-19 SB-4 OG TO TR-7 TJM 10 100 1 0.5 1.5 1 0.1 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 500 1 0.7 17 1 0.3 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 Infinity 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 Infinity 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 12 1 0.7 Infinity252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 8 1 0.7 Infinity252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 3 1 0.85 Infinity

452-18 PMCC-8 I/C FROM TR-8 CDG 31 2500 1 0.3 0.38 1 0.15 0.18252-18 SB-4 OG TO TR-7 TJM 10 100 1 0.5 1.5 1 0.1 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY






Current in CT(A)


(Sec)

Existing Service Settings ELSYTEC's Recommended Settings252-4 SB-1 OG TO SB-4 TJM 10 500 1 0.7 17 1 0.3 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 Infinity 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 Infinity 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 1 1 0.7 Infinity252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 8 1 0.7 Infinity252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 3 1 0.85 Infinity

452-17 PMCC-9 I/C FROM TR-9 CDG 31 2500 0.5 0.75 0.75 1 0.15 0.18252-17 SB-4 OG TO TR-7 TJM 10 100 0.75 0.6 1.7 1 0.1 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 500 1 0.7 17 1 0.3 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 Infinity 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 Infinity 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 Infinity 1 0.7 Infinity252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 8 1 0.7 Infinity252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 3 1 0.85 Infinity

452-16 DCD-10 I/C FROM TR-10 CDG 31 2500 0.75 0.3 0.35 1 0.15 0.18252-16 SB-4 OG TO TR-10 TJM 10 100 0.75 0.5 1.4 1 0.1 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 500 1 0.7 17 1 0.3 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 Infinity 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 Infinity 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 Infinity 1 0.7 Infinity252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 8 1 0.7 Infinity252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 3 1 0.85 Infinity

452-15 DCD-11 I/C FROM TR-11 CDG 31 2500 0.75 0.2 0.23 1 0.15 0.18252-15 SB-4 OG TO TR-11 TJM 10 100 0.75 0.5 1.4 1 0.1 0.3252-9 SB-4 I/C FROM SB-1 NO RELAY252-4 SB-1 OG TO SB-4 TJM 10 500 1 0.7 17 1 0.3 2.6252-1 SB-1 I/C FOR SB-1 TJM 10 800 0.75 0.7 Infinity 1 0.4 Infinity152-1 SB-1 I/C FROM 110kV Line ICM 21 75 0.75 0.8 Infinity 1 0.85 Infinity252-3 SB-1 TIE TO TG-1 SG CDD 31 500 1.25 0.95 Infinity 1 0.7 Infinity252-26 TG-1 TIE TO SB-1 CDD 31 500 1 0.65 8 1 0.7 Infinity252-21 TG-1 I/C FROM TG CDG 31 600 1 0.4 3 1 0.85 Infinity




S.No SB No DescriptionPrimary

Current in CT(A)

Relay Type PS TMS Tripping Time (Sec) Relay Type PS TMS Tripping Time

(Sec)

252-2 SB-1 OG TO SB-2 150 TJM 10 0.1 0.2 0.75 TJM 10 0.3 0.1 0.75252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 7 MIT 161 0.075 0.15 2.05

SB-1 GT T/F NUTRAL 100 - - - - MIT 161 0.6 0.15 2.05152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.23 ICM 21 0.75 0.2 2.30252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 1.28 MIT 161 0.1 0.15 1.51

252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.458 MIT 161 0.1 0.15 1.51252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 1.1 CDG 31 0.1 0.45 1.80

252-8 SB-2 OG TO TR-1 NO RELAY252-7 SB-2 I/C FROM SB-1 150 TJM 10 0.1 0.5 1.7 TJM 10 0.3 0.1 0.75252-2 SB-1 OG TO SB-2 150 TJM 10 0.1 0.2 0.75 TJM 10 0.3 0.1 0.75252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 1.053 MIT 161 0.075 0.15 2.05152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.28 ICM 21 0.75 0.2 2.30252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 1.28 MIT 161 0.1 0.15 1.51


252-10 SB-3 OG TO TR-2 100 TJM 10 0.1 0.1 0.31 TJM 10 0.5 0.1 0.90252-9 SB-3 I/C FROM SB-1 NO RELAY NO RELAY252-4 SB-1 OG TO SB-3 400 TJM 10 0.1 0.15 1 MIT 161 0.125 0.125 1.25252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 7 MIT 161 0.075 0.15 2.05152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.27 ICM 21 0.75 0.2 2.30252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 1.28 MIT 161 0.1 0.15 1.51


252-15 SB-4 OG TO TR-11 200 TJM 10 0.2 0.5 0.43 TJM 10 0.25 0.1 0.90252-14 SB-3 I/C FROM SB-1 NO RELAY NO RELAY252-5 SB-1 OG TO SB-4 500 TJM 10 0.2 0.8 20 MIT 161 0.1 0.125 1.25252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 7 MIT 161 0.075 0.15 2.05152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.27 ICM 21 0.75 0.2 2.30252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 1.28 MIT 161 0.1 0.15 1.51

252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.458 MIT 161 0.1 0.15 1.51




Fault at SB-1 (11kV)Existing Service Settings ELSYTEC Recommended Settings

4.2.Comparison of Existing and Recommended Settings - Earth Fault


Current in CT(A)


(Sec)

Existing Service Settings ELSYTEC Recommended Settings252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 0.5 CDG 31 0.1 0.45 1.80

252-25 TG-1 OG TO AUX.TR-3 200 CDG 31 0.1 0.1 0.16 CDG 31 0.25 0.3 0.92252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 1.3 CDG 31 0.1 0.45 1.80252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 1.053 MIT 161 0.075 0.15 2.05152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.28 ICM 21 0.75 0.2 2.30252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 1.28 MIT 161 0.1 0.15 1.51


352-1 SB-5 I/C FROM TR-2 200 TJM 10 0.1 0.1 0.43 TJM 10 0.25 0.1 0.90SB-5 TR-2 NUTRAL 200 MIT 161 - - - MIT 161 0.25 0.1 1.00

252-10 SB-3 OG TO TR-2 100 TJM 10 0.1 0.1 0.31 TJM 10 0.5 0.1 0.90252-9 SB-3 I/C FROM SB-1 NO RELAY NO RELAY252-4 SB-1 OG TO SB-3 400 MIT 161 0.1 0.15 1 MIT 161 0.125 0.125 1.25252-1 SB-1 I/C FOR SB-1 800 MIT 161 0.2 0.2 7 MIT 161 0.075 0.15 2.05152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.27 ICM 21 0.75 0.2 2.30252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 1.28 MIT 161 0.1 0.15 1.51


352-2 SB-6 I/C FROM AUX.TR-3 500 CDG 31 0.1 0.1 0.26 CDG 31 0.1 0.1 0.26SB-6 AUX.TR NUTRAL 500 - - - MIT 161 0.1 0.075 0.75

252-25 SB-1 OG TO AUX.TR-3 200 CDG 31 0.1 0.1 0.16 CDG 31 0.25 0.3 0.92252-21 SB-1 I/C FROM TG 600 CDG 31 0.1 0.3 1.1 CDG 31 0.1 0.45 1.80252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 7 MIT 161 0.075 0.15 2.05152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.27 ICM 21 0.75 0.2 2.30252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 1.28 MIT 161 0.1 0.15 1.51


452-2 PMCC-2 I/C FROM AUX.TR-2 3000 CDG 31 0.1 0.1 0.28 CDG 31 0.1 0.1 0.29PMCC-2 AUX.TR NUTRAL 3000 - - - - MIT 161 0.1 0.075 0.86

252-23 TG-1 OG TO AUX.TR-2 200 CDG 31 0.1 0.1 Infinity CDG 31 0.25 0.3 INFINITY252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 Infinity CDG 31 0.1 0.45 INFINITY252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 Infinity MIT 161 0.075 0.15 INFINITY

Fault at SB-5 (3kV)

Fault at TG PMCC-3(3.3kV)




Current in CT(A)


(Sec)

Existing Service Settings ELSYTEC Recommended Settings152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.55 ICM 21 0.75 0.2 INFINITY252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 2.22 MIT 161 0.1 0.15 INFINITY252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.793 MIT 161 0.1 0.15 INFINITY

452-11 PMCC1 I/C FROM SB2 4000 CDG 31 0.1 0.1 0.3 CDG 31 0.1 0.1 0.29PMCC1 TR-1 NUTRAL 4000 - - MIT 161 0.1 0.075 0.83

252-8 SB-2 OG TO SB-2 NO RELAY NO RELAY252-7 SB-2 I/C FROM SB-1 150 TJM 10 0.1 0.5 1.7 TJM 10 0.3 0.1 INFINITY252-2 SB-1 OG TO SB-2 150 TJM 10 0.1 0.2 1.7 TJM 10 0.3 0.1 INFINITY252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 Infinity MIT 161 0.075 0.15 INFINITY152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.45 ICM 21 0.75 0.2 INFINITY252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 1.937 MIT 161 0.1 0.15 INFINITY252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.692 MIT 161 0.1 0.15 INFINITY252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 Infinity CDG 31 0.1 0.45 INFINITY

252-12 PMCC3 I/C FROM SB-3 3000 CDG 31 0.1 0.2 0.55 CDG 31 0.1 0.1 0.25PMCC3 TR-3 NUTRAL 3000 - - MIT 161 0.1 0.075 0.67

252-11 SB-3 OG TO TR-3 125 TJM 10 0.1 0.2 1.7 TJM 10 0.4 0.1 INFINITY252-9 SB-3 I/C FROM SB1 NO RELAY NO RELAY252-4 SB-1 OG TO SB-3 400 TJM 10 0.1 0.15 Infinity MIT 161 0.125 0.125 INFINITY252-1 SB-1 I/C OF SB-1 800 TJM 10 0.2 0.2 Infinity MIT 161 0.075 0.15 INFINITY152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.5 ICM 21 0.75 0.2 INFINITY252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 2.056 MIT 161 0.1 0.15 INFINITY252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.735 MIT 161 0.1 0.15 INFINITY252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 Infinity CDG 31 0.1 0.45 INFINITY

452-13 PMCC4 I/C FROM TR-4 3000 CDG 31 0.1 0.1 0.27 CDG 31 0.1 0.1 0.24PMCC4 TR-4 NUTRAL 3000 - - - MIT 161 0.1 0.075 0.67

252-12 SB-3 OG TO TR-4 125 TJM 10 0.1 0.2 1.7 TJM 10 0.4 0.1 INFINITY252-9 SB-3 I/C FROM SB-1 NO RELAY NO RELAY252-4 SB-1 OG TO SB-3 400 TJM 10 0.1 0.15 Infinity MIT 161 0.125 0.125 INFINITY252-1 SB-1 I/C OF SB-1 800 TJM 10 0.2 0.2 Infinity MIT 161 0.075 0.15 INFINITY152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.5 ICM 21 0.75 0.2 INFINITY252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 2.051 MIT 161 0.1 0.15 INFINITY





Current in CT(A)


(Sec)

Existing Service Settings ELSYTEC Recommended Settings252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.733 MIT 161 0.1 0.15 INFINITY252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 Infinity CDG 31 0.1 0.45 INFINITY

452-14 PMCC-5 I/C FROM TR-5 3000 CDG 31 0.1 0.15 0.4 CDG 31 0.1 0.1 0.25PMCC-5 TR-5 NUTRAL 3000 - - - - MIT 161 0.1 0.075 0.68

252-13 SB-3 OG TO TR-5 125 TJM 10 0.1 0.2 1.7 TJM 10 0.4 0.1 INFINITY252-9 SB-3 I/C FROM SB-1 NO RELAY NO RELAY252-4 SB-1 OG TO SB-3 400 TJM 10 0.1 0.15 Infinity MIT 161 0.125 0.125 INFINITY252-1 SB-1 I/C OF SB-1 800 TJM 10 0.2 0.2 Infinity MIT 161 0.075 0.15 INFINITY152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.5 ICM 21 0.75 0.2 INFINITY252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 2.059 MIT 161 0.1 0.15 INFINITY252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.736 MIT 161 0.1 0.15 INFINITY252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 Infinity CDG 31 0.1 0.45 INFINITY

452-20 PMCC-6 I/C FROM TR-6 600 CDG 31 0.1 0.35 CDG 31 0.1 0.1 0.20PMCC-6 TR-6 NUTRAL 600 - - - MIT 161 0.1 0.075 0.52

252-20 SB-4 OG TO TR-6 25 TJM 10 0.1 0.1 0.7 TJM 10 2 0.1 INFINITY252-9 SB-4 I/C FROM SB-1 NO RELAY NO RELAY252-4 SB-1 OG TO SB-4 500 TJM 10 0.2 0.8 Infinity MIT 161 0.1 0.125 INFINITY252-1 SB-1 I/C OF SB-1 800 TJM 10 0.2 0.2 Infinity MIT 161 0.075 0.15 INFINITY152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 Infinity ICM 21 0.75 0.2 INFINITY252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 5.124 MIT 161 0.1 0.15 INFINITY252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 1.83 MIT 161 0.1 0.15 INFINITY252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 Infinity CDG 31 0.1 0.45 INFINITY

452-19 PMCC-7 I/C FROM TR-7 2500 CDG 31 0.1 0.1 0.26 CDG 31 0.1 0.1 0.26PMCC-7 TR-7 NUTRAL 2500 - - - MIT 161 0.1 0.075 0.70

252-19 SB-4 OG TO TR-7 100 TJM 10 0.1 0.2 1.7 TJM 10 0.5 0.1 INFINITY252-9 SB-4 I/C FROM SB-1 NO RELAY NO RELAY252-4 SB-1 OG TO SB-4 500 TJM 10 0.2 0.8 Infinity MIT 161 0.1 0.125 INFINITY252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 Infinity MIT 161 0.075 0.15 INFINITY152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.52 ICM 21 0.75 0.2 INFINITY252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 2.264 MIT 161 0.1 0.15 INFINITY252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.809 MIT 161 0.1 0.15 INFINITY252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 Infinity CDG 31 0.1 0.45 INFINITY





Current in CT(A)


(Sec)

Existing Service Settings ELSYTEC Recommended Settings

452-18 PMCC-8 I/C FROM TR-8 2500 CDG 31 0.1 0.1 0.26 CDG 31 0.1 0.1 0.25PMCC-8 TR-8 NUTRAL 2500 - - - - MIT 161 0.1 0.075 0.67


452-17 PMCC-9 I/C FROM TR-9 2500 CDG 31 0.1 0.1 0.26 CDG 31 0.1 0.1 0.26PMCC-9 TR-9 NUTRAL 2500 - - - MIT 161 0.1 0.075 0.69


452-16 DCD-10 I/C FROM TR-10 2500 CDG 31 0.4 0.5 Infinity CDG 31 0.1 0.1 0.26DCD-10 TR-10 NUTRAL 2500 - - - MIT 161 0.1 0.075 0.70

252-16 SB-4 OG TO TR-10 100 TJM 10 0.2 0.2 Infinity TJM 10 0.5 0.1 INFINITY252-9 SB-4 I/C FROM SB-1 NO RELAY NO RELAY252-4 SB-1 OG TO SB-4 500 TJM 10 0.2 0.8 Infinity MIT 161 0.1 0.125 INFINITY252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 Infinity MIT 161 0.075 0.15 INFINITY152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.45 ICM 21 0.75 0.2 INFINITY252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 2.262 MIT 161 0.1 0.15 INFINITY252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.808 MIT 161 0.1 0.15 INFINITY252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 Infinity CDG 31 0.1 0.45 INFINITY

452-15 DCD-11 I/C FROM TR-11 2500 CDG 31 0.4 0.5 Infinity CDG 31 0.1 0.1 0.26Fault at DCD 11 (433V)





Current in CT(A)


(Sec)

Existing Service Settings ELSYTEC Recommended SettingsDCD-11 TR-11 NUTRAL 2500 - - - MIT 161 0.1 0.075 0.69

252-15 SB-4 OG TO TR-11 100 TJM 10 0.2 0.5 Infinity TJM 10 0.5 0.1 INFINITY252-9 SB-4 I/C FROM SB-1 NO RELAY NO RELAY252-4 SB-1 OG TO SB-4 500 TJM 10 0.2 0.8 Infinity MIT 161 0.1 0.125 INFINITY252-1 SB-1 I/C FOR SB-1 800 TJM 10 0.2 0.2 Infinity MIT 161 0.075 0.15 INFINITY152-1 SB-1 I/C FROM 110kV Line 75 ICM 21 0.1 0.1 0.45 ICM 21 0.75 0.2 INFINITY252-3 SB-1 TIE TO TG-1 SG 500 MIT 161 0.005 0.7 2.257 MIT 161 0.1 0.15 INFINITY252-26 TG-1 TIE TO SB-1 500 MIT 161 0.005 0.25 0.806 MIT 161 0.1 0.15 INFINITY252-21 TG-1 I/C FROM TG 600 CDG 31 0.1 0.3 Infinity CDG 31 0.1 0.45 INFINITY

5. Proposed additional Relays recommended Relays to be procured & installed in all Transformer secondary neutral side at following places

1. GT 2. Tr-1 3. Tr-2 4. Tr-3 5. Tr-4 6. Tr-5 7. Tr-6 8. Tr-7 9. Tr-8 10. Tr-9 11. Tr-10 12. Tr-11 13. Aux.Tr-1 14. Aux.Tr-2 15. Aux.Tr-3 and also 252-1 Incoming from 10/12.5MVA Transformer 252-4 Outgoing to SB-3 from SB-1. 252-5 Outgoing to SB-4 from SB-1 252-3 Tie feeder from SB-1 to TG 252-26 Tie feeder from TG to SB-1 In the above places MIT 161 type of relays is recommended to installed and CT

ratios to match with LT side CT’s respective Breakers. (Refer 3.2.1.)

5. RECOMMENDED SETTINGS FOR OVER CURRENT &

EARTH FAULT

Device No Device Location Relay Type CT Ratio Plug Settings TMS

152-1 I/C FROM 110kV LINE ICM 21 75/1A 1 0.85252-1 I/C FOR SB-1 TJM 10 800/1A 1 0.4252-2 OG TO SB-2 FROM SB-1 TJM 10 150/1A 1 0.3252-3 TIE TO SB-1 TO TG1 CDD 31 500/1A 1 0.7252-4 OG TO SB-3 FROM SB-1 TJM 10 400/1A 1 0.3252-5 OG TO SB-4 FROM SB-1 TJM 10 500/1A 1 0.3252-7 I/C FROM SB-1 IN SB-2 TJM 10 150/1A 1 0.3252-8 OG TO TR-1 FROM SB-2 - - - -252-9 I/C FROM SB-1 IN SB-3 - - - -252-10 OG TO TR-2 FROM SB-3 TJM 10 100/1A 0.75 0.1252-11 OG TO TR-3 FROM SB-3 TJM 10 125/1A 1 0.1252-12 OG TO TR-4 FROM SB-3 TJM 10 125/1A 1 0.1252-13 OG TO TR-5 FROM SB-3 TJM 10 125/1A 1 0.1252-14 I/C FROM SB-1 IN SB-4 - - - -252-15 OG TO TR-11 FROM SB-4 TJM 10 100/1A 1 0.1252-16 OG TO TR-10 FROM SB-4 TJM 10 100/1A 1 0.1252-17 OG TO TR-9 FROM SB-4 TJM 10 100/1A 1 0.1252-18 OG TO TR-8 FROM SB-4 TJM 10 100/1A 1 0.1252-19 OG TO TR-7 FROM SB-4 TJM 10 100/1A 1 0.1252-20 OG TO TR-6 FROM SB-4 TJM 10 100/1A 1 0.1252-21 I/C FROM TG IN TG SG CDG 31 600/1A 1 0.85252-22 OG TO Aux.TR-1 FROM TG1 CDG 31 200/1A 1 0.3252-23 OG TO Aux.TR-2 FROM TG1 CDG 31 200/1A 1 0.3252-25 OG TO Aux.TR-3 FROM TG1 CDG 31 200/1A 1 0.3252-26 TIE TO TG1 TO SB-1 CDD 31 500/1A 1 0.7352-1 I/C FROM TR-2 IN SB-5 TJM 10 200/1A 1 0.1352-2 I/C FROM Aux.TR-3 IN TG PMCC-3 CDG 31 500/1A 1 0.1452-1 I/C FROM Aux.TR-1 IN TG PMCC-1 CDG 31 3000/1A 1 0.1452-2 I/C FROM Aux.TR-2 IN TG PMCC-2 CDG 31 3000/1A 1 0.1452-11 I/C FROM TR-1 IN PMCC-1 CDG 31 4000/1A 1 0.15452-12 I/C FROM TR-3 IN PMCC-3 CDG 31 3000/1A 1 0.15452-13 I/C FROM TR-4 IN PMCC-4 CDG 31 3000/1A 1 0.15452-14 I/C FROM TR-5 IN PMCC-5 CDG 31 3000/1A 1 0.15452-15 I/C FROM TR-11 IN DCD-11 CDG 31 2500/1A 1 0.15452-16 I/C FROM TR-10 IN DCD-10 CDG 31 2500/1A 1 0.15452-17 I/C FROM TR-9 IN PMCC-9 CDG 31 2500/1A 1 0.15452-18 I/C FROM TR-8 IN PMCC-8 CDG 31 2500/1A 1 0.15452-19 I/C FROM TR-7 IN PMCC-7 CDG 31 2500/1A 1 0.15452-20 I/C FROM TR-6 IN PMCC-6 CDG 31 600/1A 1 0.15

RECOMMENDED SETTINGS FOR OVER CURRENT

RECOMMENDED SETTINGS FOR OVER CURRENT AND EARTH FAULT BY ELSYTEC

49

Device No Device Location Relay Type CT RatioPlug

Settings TMS152-1 I/C FROM 110kV LINE ICM 21 75/1A 0.75 0.2252-1 I/C FOR SB-1 MIT 161 800/1A 0.075 0.15252-2 OG TO SB-2 FROM SB-1 TJM 10 150/1A 0.3 0.1252-3 TIE TO SB-1 TO TG1 MIT 161 500/1A 0.1 0.15252-4 OG TO SB-3 FROM SB-1 MIT 161 400/1A 0.125 0.125252-5 OG TO SB-4 FROM SB-1 MIT 161 500/1A 0.1 0.125252-7 I/C FROM SB-1 IN SB-2 TJM 10 150/1A 0.3 0.1252-8 OG TO TR-1 FROM SB-2 - - - -252-9 I/C FROM SB-1 IN SB-3 - - - -252-10 OG TO TR-2 FROM SB-3 TJM 10 100/1A 0.5 0.1252-11 OG TO TR-3 FROM SB-3 TJM 10 125/1A 0.4 0.1252-12 OG TO TR-4 FROM SB-3 TJM 10 125/1A 0.4 0.1252-13 OG TO TR-5 FROM SB-3 TJM 10 125/1A 0.4 0.1252-14 I/C FROM SB-1 IN SB-4 - - - -252-15 OG TO TR-11 FROM SB-4 TJM 10 100/1A 0.5 0.1252-16 OG TO TR-10 FROM SB-4 TJM 10 100/1A 0.5 0.1252-17 OG TO TR-9 FROM SB-4 TJM 10 100/1A 0.5 0.1252-18 OG TO TR-8 FROM SB-4 TJM 10 100/1A 0.5 0.1252-19 OG TO TR-7 FROM SB-4 TJM 10 100/1A 0.5 0.1252-20 OG TO TR-6 FROM SB-4 TJM 10 100/1A 2 0.1252-21 I/C FROM TG IN TG SG CDG 31 600/1A 0.1 0.45252-22 OG TO Aux.TR-1 FROM TG1 CDG 31 200/1A 0.25 0.3252-23 OG TO Aux.TR-2 FROM TG1 CDG 31 200/1A 0.25 0.3252-25 OG TO Aux.TR-3 FROM TG1 CDG 31 200/1A 0.25 0.3252-26 TIE TO TG1 TO SB-1 MIT 161 500/1A 0.1 0.15352-1 I/C FROM TR-2 IN SB-5 TJM 10 200/1A 0.5 0.1352-2 I/C FROM Aux.TR-3 IN TG PMCC-3 CDG 31 500/1A 0.1 0.1452-1 I/C FROM Aux.TR-1 IN TG PMCC-1 CDG 31 3000/1A 0.1 0.1452-2 I/C FROM Aux.TR-2 IN TG PMCC-2 CDG 31 3000/1A 0.1 0.1452-11 I/C FROM TR-1 IN PMCC-1 CDG 31 4000/1A 0.1 0.1452-12 I/C FROM TR-3 IN PMCC-3 CDG 31 3000/1A 0.1 0.1452-13 I/C FROM TR-4 IN PMCC-4 CDG 31 3000/1A 0.1 0.1452-14 I/C FROM TR-5 IN PMCC-5 CDG 31 3000/1A 0.1 0.1452-15 I/C FROM TR-11 IN DCD-11 CDG 31 2500/1A 0.1 0.1452-16 I/C FROM TR-10 IN DCD-10 CDG 31 2500/1A 0.1 0.1452-17 I/C FROM TR-9 IN PMCC-9 CDG 31 2500/1A 0.1 0.1452-18 I/C FROM TR-8 IN PMCC-8 CDG 31 2500/1A 0.1 0.1452-19 I/C FROM TR-7 IN PMCC-7 CDG 31 2500/1A 0.1 0.1452-20 I/C FROM TR-6 IN PMCC-6 CDG 31 600/1A 0.1 0.1

GT NEUTRAL MIT 161 100/1A 0.6 0.15TR-1 NEUTRAL MIT 161 4000/1A 0.1 0.075TR-2 NEUTRAL MIT 161 200/1A 0.25 0.1TR-3 NEUTRAL MIT 161 3000/1A 0.1 0.075TR-4 NEUTRAL MIT 161 3000/1A 0.1 0.075TR-5 NEUTRAL MIT 161 3000/1A 0.1 0.075TR-6 NEUTRAL MIT 161 600/1A 0.1 0.075TR-7 NEUTRAL MIT 161 2500/1A 0.1 0.075TR-8 NEUTRAL MIT 161 2500/1A 0.1 0.075TR-9 NEUTRAL MIT 161 2500/1A 0.1 0.075TR-10 NEUTRAL MIT 161 2500/1A 0.1 0.075TR-11 NEUTRAL MIT 161 2500/1A 0.1 0.075Aux.TR-1 NEUTRAL MIT 161 3000/1A 0.1 0.075Aux.TR-2 NEUTRAL MIT 161 3000/1A 0.1 0.075

RECOMMENDED SETTINGS FOR EARTH FAULT

50

Aux.TR-3 NEUTRAL MIT 161 500/1A 0.1 0.075

51

3.1.1.Fault Calculations for Over Current

Documents

110kv line

existing service

existing relay

elsytec recommended

110kv line

ipu tripping

tr nutral

existing amp