Light Railway Transit (LRT)
National Authority for Tunnels (NAT)
Electrical
Inspection Test Plan Manual
Power
Transformers
Protection
Relays
L.R.T
Prepared By:
Usama Ali Taha
Testing and Comissioning Engineer
CREC-AVIC INTL.
Revised By:
Mahmoud Abd ELShafy
Senior Power Supply Engineer
Khatib&Alami
Mariam Adel
Senior Power Supply Engineer
National Authority for Tunnels
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Introduction
We provide a guidebook for the owner to supervise and follow up
Testing and Commissioning for all the power supply equipment’s in
LRT project.
Why Testing and Commissioning?
- To assure all tested equipment or system supplied by contractor within applicable
standards and manufacturer’s tolerance.
- To assure that the systems are installed accordance with design
specification:
• Shipping and installation damage.
• Field and factory wiring errors.
• Manufacturing defects and system.
• Components not accordance with drawing and specification.
• And some of the problem can be detected during testing only.
- When these defects found before start-up, they can be corrected under warranty
without safety hazard.
- Consequential damage of loss / production that can be occur if discovered after
start-up or energizing.
Page | 2
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
References
•
•
•
•
•
Page | 3
ASNI: American national standards institute
IEEE: Institute for electrical and electronic engineers
IE: International electro technical committee.
CSD Commissioning Manual
Madkour & El-Fanar Testing Team
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Content
Table of Contents
Introduction: ...........................................................................................................................................2
References: ..............................................................................................................................................3
GIS and Switchgears............................................................................ 11
GIS HV CB Tests ..................................................................................................................... 11
Mechanical Check and Visual Inspection: ..................................................................................... 13
Spring Charging Motor: ................................................................................................................. 14
Coil Resistance Test: ....................................................................................................................... 14
Timing Test: .................................................................................................................................... 15
SWGR MV CB Tests................................................................................................................ 17
Mechanical Check and Visual Inspection: ..................................................................................... 19
Insulation Resistance Test: ............................................................................................................. 20
Spring Charging Motor: ................................................................................................................. 21
Coil Resistance Test: ....................................................................................................................... 21
Contact Resistance Test: ................................................................................................................. 22
Timing Test: .................................................................................................................................... 23
GIS HV DS Procedure Tests .................................................................................................... 25
Mechanical Check and Visual Inspection: ..................................................................................... 27
Timing Test: .................................................................................................................................... 27
SWGR MV DS Procedure Tests ........................................................................................................... 29
Mechanical Check and Visual Inspection: ..................................................................................... 31
Timing Test: .................................................................................................................................... 31
Contact Resistance Test: ................................................................................................................. 33
GIS BB Contact Resistance Procedure Tests .......................................................................... 34
Mechanical Check and Visual Inspection: ..................................................................................... 36
Contact Resistance Test: ................................................................................................................. 36
SWGR BB Contact Resistance Procedure Tests ..................................................................... 37
Mechanical Check and Visual Inspection: ..................................................................................... 39
Contact Resistance Test: ................................................................................................................. 39
GIS HV Procedure Tests.......................................................................................................... 40
Page | 4
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Mechanical and Visual Inspection Test: ......................................................................................... 42
Measurement of insulation Resistance Test: .................................................................................. 43
High Voltage and PD (Partial Discharge) Test: ............................................................................. 44
SWGR HV Procedure Tests .................................................................................................... 50
Mechanical and Visual Inspection Test: ......................................................................................... 52
Measurement of insulation Resistance Test: .................................................................................. 53
High Voltage Test:........................................................................................................................... 54
SWGR Mechanical Interlock Procedure Test......................................................................... 56
Mechanical Interlock Check: .......................................................................................................... 57
GIS Mechanical Interlock Procedure Test .............................................................................. 59
Mechanical Interlock Check: .......................................................................................................... 60
Surge Arrestor Procedure Test................................................................................................ 62
Mechanical and Visual Inspection Test: ......................................................................................... 64
Insulation Resistance Test: ............................................................................................................. 65
loss factor tan δ and capacitance C Test: ....................................................................................... 66
GIS Primary Injection Procedure Test ................................................................................... 68
Primary Injection Test .................................................................................................................... 70
SWGR Primary Injection Procedure Test .............................................................................. 72
Primary Injection Test .................................................................................................................... 74
Current Transformers ......................................................................... 76
CT Procedure Tests.................................................................................................................. 76
Mechanical Check and Visual Inspection: ..................................................................................... 78
Winding Resistance Test: ................................................................................................................ 80
Turns Ratio-Polarity Test: .............................................................................................................. 82
Excitation Curve Test: .................................................................................................................... 83
Burden Test: .................................................................................................................................... 84
CT Loop Procedure Test.......................................................................................................... 86
Secondary Loop current Injection Test:......................................................................................... 88
Loop Resistance and Burden Test: ................................................................................................. 89
Voltage Transformers .......................................................................... 90
VT Procedure Tests.................................................................................................................. 90
Mechanical Check and Visual Inspection: ..................................................................................... 92
Page | 5
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Insulation Resistance Test: ............................................................................................................. 92
Winding Resistance Test ................................................................................................................. 94
Polarity Check Test:........................................................................................................................ 95
Turns Ratio Error Test: .................................................................................................................. 96
Burden Test: .................................................................................................................................... 98
VT Loop Procedure Test.......................................................................................................... 99
Secondary Loop Voltage Injection Test: ...................................................................................... 101
Power Transformers .......................................................................... 102
Procedure Tests ...................................................................................................................... 102
Mechanical Check and Visual Inspection: ................................................................................... 105
Polarization Index Test: ................................................................................................................ 105
Turns-Ratio (TTR) Test:............................................................................................................... 107
DC Winding Resistance Test: ....................................................................................................... 108
loss factor tan δ and capacitance C of the winding Test: ............................................................. 110
loss factor tan δ and capacitance C of the Bushing Test .............................................................. 113
Zero sequence impudence Test ..................................................................................................... 115
Vector Group Check Test ............................................................................................................. 116
Magnetic Balance Test .................................................................................................................. 118
Short Circuit Impedance Test....................................................................................................... 120
Excitation Current (No load) Test ................................................................................................ 122
SFRA Test ..................................................................................................................................... 124
Oil and Winding Temperature Calibration Test.......................................................................... 131
On Load Tap Changer Test .......................................................................................................... 133
Oil Dielectric Breakdown Test ...................................................................................................... 135
Supervision Equipment Functional Test ...................................................................................... 137
Traction Transformers ...................................................................... 139
Procedure Tests ...................................................................................................................... 139
Mechanical Check and Visual Inspection: ................................................................................... 142
Polarization Index Test: ................................................................................................................ 142
Turns-Ratio (TTR) Test:............................................................................................................... 144
DC Winding Resistance Test: ....................................................................................................... 145
Loss factor tan δ and capacitance C of the winding Test: ............................................................ 147
Page | 6
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
loss factor tan δ and capacitance C of the Bushing Test .............................................................. 150
Vector Group Check Test ............................................................................................................. 152
Magnetic Balance Test .................................................................................................................. 154
Short Circuit Impedance Test....................................................................................................... 156
Excitation Current (No load) Test ................................................................................................ 158
SFRA Test ..................................................................................................................................... 160
Oil and Winding Temperature Calibration Test.......................................................................... 166
On Load Tap Changer Test .......................................................................................................... 168
Oil Dielectric Breakdown Test ...................................................................................................... 170
Supervision Equipment Functional Test ...................................................................................... 172
Auxiliary Transformer ...................................................................... 174
Procedure Tests ...................................................................................................................... 174
Mechanical Check and Visual Inspection: ................................................................................... 176
Polarization Index Test: ................................................................................................................ 176
Turns-Ratio (TTR) Test:............................................................................................................... 177
DC Winding Resistance Test: ....................................................................................................... 178
Grounding Transformer.................................................................... 181
Procedure Tests ...................................................................................................................... 181
Mechanical Check and Visual Inspection: ................................................................................... 183
Polarization Index Test: ................................................................................................................ 183
DC Winding Resistance Test: ....................................................................................................... 185
Zero Sequence Impedance Test: ................................................................................................... 186
Neutral Resistor Test: ................................................................................................................... 187
Neutral Current Transformer Test: ............................................................................................. 187
Stability Tests ..................................................................................... 188
Power Transformer Stability Procedure Test ....................................................................... 188
Power Transformer Stability Test ................................................................................................ 191
Traction Transformer Stability Procedure Test ................................................................... 195
Traction transformer Stability Test ............................................................................................. 198
Busbar Stability Procedure Test............................................................................................ 205
Busbar Stability Test..................................................................................................................... 207
(REF) Restricted Earth Fault Stability Procedure Test ....................................................... 211
Page | 7
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Restricted Earth Fault (REF) Stability Test................................................................................. 215
HV Under Ground Feeder Stability Procedure Test ............................................................ 218
HV Under Ground Feeder Stability Test ..................................................................................... 220
Meters Tests ....................................................................................... 226
Digital Meters Test ................................................................................................................. 226
Mechanical and Visual Inspection Test: ....................................................................................... 228
Secondary Current and Voltage Injection Test: .......................................................................... 228
Energy Meter Procedure Test ............................................................................................... 230
Mechanical and Visual Inspection Test: ....................................................................................... 232
Secondary Current and Voltage Injection Test: .......................................................................... 232
SF6 Gas Tests ..................................................................................... 235
SF6 Analysis Procedure Test ................................................................................................. 235
SF6 Analysis Test .......................................................................................................................... 238
SF6 Gauge Procedure Test .................................................................................................... 239
SF6 Gauge Test ............................................................................................................................. 240
MV Cables Tests ................................................................................ 241
VLF Procedure Test ............................................................................................................... 241
Measurement of insulation Resistance Test: ................................................................................ 243
High Voltage Test:......................................................................................................................... 245
Batteries Tests .................................................................................... 246
Battery Discharge Procedure Test ......................................................................................... 246
Battery Discharge Test: ................................................................................................................ 248
Static Var Generator Tests ................................................................ 250
SVG Procedure Tests ............................................................................................................. 250
Contact Resistance Test: ............................................................................................................... 252
Circuit Breaker Timing Test: ....................................................................................................... 253
Current Transformer Tests: ......................................................................................................... 254
Step Down Transformer Tests: ..................................................................................................... 260
High Voltage Tests: ....................................................................................................................... 265
Measurement of insulation Resistance: ........................................................................................ 266
PLC Function Test: ....................................................................................................................... 267
Page | 8
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Cold Run Test: .............................................................................................................................. 267
Hot Run Test: ................................................................................................................................ 267
Protection Function Test:.............................................................................................................. 268
Scheme Check Test: ...................................................................................................................... 268
POWER QUALITY ANALYZER IMAGE BEFORE ENERGIEZ Test: .................................. 268
POWER QUALITY ANALYZER IMAGE AFTER ENERGIEZ Test: ..................................... 268
Protection Relays Tests ...................................................................... 269
PCS-931 Relay Functions Test Procedures ........................................................................... 269
Mechanical Check and Visual Inspection: ................................................................................... 273
Electrical Tests: ............................................................................................................................. 273
Earth Fault Protection (50G/51G/IDMT_ROC) Test .................................................................. 274
Inverse time of EF protection test ................................................................................................. 275
Overcurrent protection (50P/51P/IDMT_OC) ............................................................................. 277
Definite time of OC protection test ............................................................................................... 277
Inverse time of Overcurrent protection Test ................................................................................ 278
Line Differential Protection (87L) Test ........................................................................................ 280
Steady State (Biased 87L) Differential Relay ............................................................................... 282
Steady State (Biased 87L) Differential Relay ............................................................................... 286
Zero Sequence Differential Protection (87 Neutral) Test ............................................................. 290
87 Function blocked by CTS Test ................................................................................................. 295
87 Interstrip function Test ............................................................................................................ 296
Distance Protection (21M/21Q) Test............................................................................................. 298
Distance Protection (21Q) ............................................................................................................. 299
Distance Tele-Protection Schemes Test ........................................................................................ 310
Permissive Underreaching Transfer Trip (PUTT) ....................................................................... 312
Blocking Transfer Trip ................................................................................................................. 314
Switch onto fault protection (21SOTF/50PSOTF) ....................................................................... 316
Switch onto fault protection (21SOTF) By Manual Close BI: ..................................................... 316
Switch onto fault protection (21SOTF) By Breaker Position BI: ................................................ 317
Switch onto fault protection (50PSOTF) By Breaker Position BI: .............................................. 319
Reverse Power (32R) Protection Test ........................................................................................... 320
Auto Reclose (79) and Synch Check Protection Test ................................................................... 322
Synch Check Test .......................................................................................................................... 328
Page | 9
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Over Voltage and Under Voltage Protection Functions(59P/27P) Test ....................................... 330
Broken Conductor (46BC) Protection Function .......................................................................... 331
Thermal Overload (49).................................................................................................................. 333
Power Swing Releasing Block Protection Function Test .............................................................. 335
VTS (Voltage Supervision) Protection Function .......................................................................... 337
Loss of one or two phases test: ...................................................................................................... 337
CHECK THE FUSE FAIL UNBLOCKING BY I2> and Io>...................................................... 338
Check the relay unblocking trip during internal fuse fail for Io & I ........................................... 338
Testing of 3 phase voltages loss (detect 3p) ................................................................................... 338
DELTA I> Test.............................................................................................................................. 339
Absence of 3 phase volts online Energization test ........................................................................ 339
Fault Locator Protection Function (FL) ....................................................................................... 339
PCS-978 Power Transformer Relay Functions Procedure Test ........................................... 341
Transformer Differential Protection (87T) Test........................................................................... 345
Inrush Current 2nd Harmonics Blocking Test .............................................................................. 354
Inrush Current 3rd and 5th Harmonics Blocking Test .................................................................. 355
Restricted Earth Fault (64REF) Protection Test.......................................................................... 356
Over Excitation (24DT) Protection Function Test ....................................................................... 361
PCS-9671S Traction Transformer Relay Functions Procedure Test ................................... 363
Transformer Differential Protection (87T) Test........................................................................... 368
Inrush Current 2nd Harmonics Blocking Test .............................................................................. 376
Over Excitation (24DT) Protection Function Test ....................................................................... 378
PCS-9151C BBP Relay Protection Functions Test Procedure ............................................. 380
Busbar Differential Protection (87BBP) Test ............................................................................... 384
Feeder Breaker Failure Protection (BFP) Test ............................................................................ 391
PCS-9151 ATS Relay Protection Functions Procedure Test ................................................ 396
Automatic Transfer Switch (ATS) Test ........................................................................................ 399
MR TAPCON 260 AVR Relay Functions Procedure Test ................................................... 405
Automatic Voltage Regulator (AVR) Test.................................................................................... 408
End to End Procedure Test ................................................................................................................. 420
Mechanical and Visual Inspection Test: ....................................................................................... 422
End To End of Differential Over Head T.L Test: ........................................................................ 423
Page | 10
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
GIS And Switchgears
GIS HV CB Tests
Page | 11
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Circuit Breaker Technical Data (Name Plate)
Manufacturer
Type
Bay No.
Rated Current
Rated Voltage
Short Circuit Current
Rated Frequency
Rated Gas Pressure
Coil Voltage
Production date
Serial No.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
EGIL
Megger
2
Multimeter
OMICRON
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 12
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that circuit breaker is ready to test and doesn’t have any
damage parts which prevents perfuming tests.
REMARKS
#
TEST DESCRIPTION
(OK / NOT OK)
1.
Inspect bus for physical damage or defects.
2.
Check nameplate information for correctness.
3.
Check tightness of all bolted connections (torque wrench method).
4.
Check all wiring is correct according to approved drawings and that terminal
connections are secure.
5.
Check quality of paintwork.
6.
Check that all grounding cables are securely connected.
7.
Check for correct breaker position indication (breaker open/closed).
8.
Check operation of all mechanical interlocks with associated disconnects,
grounding switches, racking truck mechanism, cubicle doors, etc.
9.
Verify correct spring status indication (spring charged/discharged).
10. Check for gas leakage.
11. Check for correct SF6 pressure in each pole.
12. Verify that all special filling adapters have been provided.
Perform all specific checks on the mechanism according to the manufacturer’s
13. instructions.
14. Verify that correct Dispatch Numbers have been installed.
Page | 13
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Spring Charging Motor:
3.1.2) Purpose of test:
- Calculate max spring motor current and spring charging time to compare
them with name plate or FAT values.
➢ Criteria: (As per FAT): 660/1100 W, Current ~ 5Amp
➢ Note: This test is performed for GIS/SWG circuit breakers.
3.1.3) Work Instructions/Test Procedures:
1- Connect multimeter by spring motor circuit.
2- Close the breaker.
3- Evaluate results for max current and time for this by stopwatch.
4- Compare measured values by FAT results if accepted.
5- Repeat this step at 85% of operating voltage.
Coil Resistance Test:
3.1.4) Purpose of test:
- Make sure that closing and opening coil resistance within range value of
FAT results.
➢ Criteria: (As per FAT Results).
➢ Note: This test is performed for GIS/SWG circuit breakers.
3.1.5) Work Instructions/Test Procedures:
1- Connect props of multimeter by closing and opening terminals coil.
2- Evaluate results for closing - opening1,2 coil.
3- Compare measured values by FAT results if accepted.
Page | 14
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
PHASE
Closing Coil (Ω)
Opening Coil1 (Ω) Opening Coil2 (Ω)
R
S
T
Timing Test:
3.1.6) Purpose of test:
- This test is used on medium and high-voltage circuit breakers and provides
information as to whether the operating mechanism of the circuit breaker is
operating properly or not by measuring the closing and opening time of the breaker
contacts.
- This test can be used to determine the opening and closing speeds of the breaker,
the interval time for closing and tripping and the contact bounce. The test provides
information that can be used to detect problems such as weak accelerating springs,
defective shock absorbers, dashpots, buffers, and closing mechanisms.
- Make sure circuit breaker poles at closing and opening position time is
within range of times value of FAT results.
3.1.7) Work Instructions/Test Procedures :
1- Preparing connection of EGIL tester as shown below.
2- Connect external DC supply for closing and tripping coils.
3- Connect wires for closing and tripping coils at schematic DWG.
4- Connect sensing current feedback cable as shown.
5- Evaluate results for each sequence and compared it by FAT results.
6- Repeat same sequence at 85% of voltage supply.
➢ Criteria: (As per FAT): Closing time 35-70ms & Opening Time 25-40ms.
➢ Note: This results for GIS CB.
Page | 15
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Applied Voltage
(V)
Timing (ms)
Operation
Close
Open1
Open2
Close-Open1
100% VDC
Close-Open2
OCO1
OCO2
Close
85% VDC
Open1
Open2
Page | 16
R
S
T
Aux
Contact
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SWGR MV CB Tests
Page | 17
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Circuit Breaker Technical Data (Name Plate)
Manufacturer
Type
Bay No.
Rated Current
Rated Voltage
Short Circuit Current
Rated Frequency
Production date
Coil Voltage
Serial No.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers
S.N
Type
Make
1
EGIL
Megger
2
Multimeter
OMICRON
3
Megger 5K VDC
Megger
4
Ohmmeter
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 18
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that circuit breaker is ready to test and doesn’t have any damage
parts which prevents perfuming tests.
REMARKS
#
TEST DESCRIPTION
(OK / NOT OK)
15. Inspect bus for physical damage or defects.
16. Check nameplate information for correctness.
17. Check tightness of all bolted connections (torque wrench method).
Check all wiring is correct according to approved drawings and that terminal
18. connections are secure.
19. Check quality of paintwork.
20. Check that all grounding cables are securely connected.
21. Check for correct breaker position indication (breaker open/closed).
Check operation of all mechanical interlocks with associated disconnects,
22. grounding switches, racking truck mechanism, cubicle doors, etc.
23. Verify correct spring status indication (spring charged/discharged).
24. Check for gas leakage.
25. Check for correct SF6 pressure in each pole.
26. Verify that all special filling adapters have been provided.
Perform all specific checks on the mechanism according to the
27. manufacturer’s instructions.
28. Verify that correct Dispatch Numbers have been installed.
Page | 19
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Insulation Resistance Test:
3.2.1) Purpose of test:
- To determine the equipment in proper condition to put in service. Results can
be kept as record to compare in future and to understand the trend of
insulation during maintenance.
➢ Applied Voltage: 5000V DC
➢ Criteria: (As per FAT): More than 2500 MΩ.
➢ Note: this test is performed for GIS/SWG circuit breakers.
3.2.2) Work Instructions/Test Procedures:
1- Connect megger tester as shown below.
2- Apply voltage test value for each connection.
3- Close circuit breaker.
4- Repeat this step for phase Y and B.
5- Evaluate test results and compare it by FAT results.
Insulation Resistance test between R phase and Y,B phase are earthed.
R
CB
Close
Page | 20
R
S
EARTH
S
T
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Spring Charging Motor:
3.3.1) Purpose of test:
- Calculate max spring motor current and spring charging time to compare them
with name plate or FAT values.
➢ Criteria: (As per FAT): 660/1100 W, Current ~ 5Amp
3.3.2) Work Instructions/Test Procedures:
1- Connect multimeter by spring motor circuit.
2- Close the breaker.
3- Evaluate results for max current and time for this by stopwatch.
4- Compare measured values by FAT results if accepted.
5- Repeat this step at 85% of operating voltage.
Coil Resistance Test:
3.4.1) Purpose of test:
- Make sure that closing and opening coil resistance within range value of FAT
results.
➢ Criteria: (As per FAT Results).
3.4.2) Work Instructions/Test Procedures:
1- Connect props of multimeter by closing and opening terminals coil.
2- Evaluate results for closing - opening1,2 coil.
3- Compare measured values by FAT results if accepted.
PHASE
R
S
T
Page | 21
Closing Coil (Ω)
Opening Coil1 (Ω)
Opening Coil2 (Ω)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Contact Resistance Test:
3.5.1) Purpose of test:
- Contact resistance tests are usually performed using a micro/milliohm meter
or a low ohmmeter. The measurement of contact resistance helps to identify
fretting corrosion of contacts and can diagnose and prevent contact
corrosion. An increase in contact resistance can cause a high voltage to drop
in the system and needs to be controlled.
- Make sure contact resistance of 3 poles of circuit breaker within range value
of FAT results.
3.5.2) Work Instructions/Test Procedures:
1- Select path for injection current start and end point.
2- Connect cables of ohmmeter tester at selected path.
3- Start test be increase gradually injected current until 100A value.
4- Evaluate results for all selected paths.
5- Compare between measured values and FAT results if accepted.
6- Evaluate all results values and filling down test table formats.
➢ Injected Current: 100A DC
➢ Criteria: (As per FAT): within +/- 5% of FAT test Reports. (≤30 µΩ per
phase).
➢ Note: this test is performed for medium SWG.
Phase Result (µΩ)
R
S
T
Page | 22
Remarks
(OK / NOT OK)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Timing Test:
3.6.1) Purpose of test:
- This test is used on medium and high-voltage circuit breakers and provides
information as to whether the operating mechanism of the circuit breaker is
operating properly or not by measuring the closing and opening time of the
breaker contacts.
- This test can be used to determine the opening and closing speeds of the breaker,
the interval time for closing and tripping and the contact bounce. The test
provides information that can be used to detect problems such as weak
accelerating springs, defective shock absorbers, dashpots, buffers, and closing
mechanisms.
- Make sure circuit breaker poles at closing and opening position time is within
range of times value of FAT results.
3.6.2) Work Instructions/Test Procedures:
1- Preparing connection of EGIL tester as shown below.
2- Connect external DC supply for closing and tripping coils.
3- Connect wires for closing and tripping coils at schematic DWG.
4- Connect sensing current feedback cable as shown.
5- Evaluate results for each sequence and compared it by FAT results.
6- Repeat same sequence at 85% of voltage supply.
➢ Note: This test is performed for GIS/SWG circuit breakers.
Page | 23
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Criteria: (As per FAT): Closing time 35-70ms & Opening Time 25-40ms.
Applied Voltage
(V)
Timing (ms)
Operation
R
S
T
Aux
Contact
Close
Open
100% VDC
OCO
Close
85% VDC
Open
➢ Criteria: (As per FAT): Closing time 35-70ms & Opening Time 25-40ms.
Page | 24
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
GIS HV DS Procedure Tests
Page | 25
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Disconnector Switch Technical Data (Name Plate)
Rated SF6 Gas
Manufacturer
Pressure
Make
Rated Voltage
Rated Current
Rated Frequency
Short Circuit Current
Coil Voltage
Spring Motor Voltage
Serial No.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers
S.N
Type
Make
1
EGIL
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 26
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that circuit breaker is ready to test and doesn’t have any damage
parts which prevents perfuming tests.
#
TEST DESCRIPTION
REMARKS
(OK / NOT OK)
29. Inspect for any physical damage or defects.
30. Check name plate information for correctness.
31. Check for disconnector switch position indication (open/close)
32. Perform all specific checks as per manufacturer's recommendations.
33. Verify connection as per approved drawing.
34. Check that all grounding cables are securely connected.
Timing Test:
3.2.1) Purpose of test:
- This test is used on medium and high-voltage disconnectors provides
information as to whether the operating mechanism of the disconnector is
operating properly or not by measuring the closing and opening time of the
breaker contacts.
- This test can be used to determine the opening and closing speeds of the
disconnector, the interval time for closing and tripping and the contact
bounce. The test provides information that can be used to detect problems
such as weak accelerating springs, defective shock absorbers, dashpots,
buffers, and closing mechanisms.
- Make sure disconnectors poles at closing and opening position time is
within range of times value of FAT results.
Page | 27
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.2.2) Work Instructions/Test Procedures :
1- Preparing connection of EGIL tester as shown below.
2- Connect external DC supply for closing and tripping coils.
3- Connect wires for closing and tripping coils at schematic DWG.
4- Connect sensing current feedback cable as shown.
5- Evaluate results for each sequence and compared it by FAT results.
6- Repeat same sequence at 85% of voltage supply.
➢ Note: This test is performed for GIS/SWG circuit breakers.
➢ Criteria: (As per FAT): Closing ≤6sec, Opening ≤6sec)
Applied Voltage
(V)
Timing (s)
Operation
Close
100% VDC
Open
Close
85% VDC
Open
Page | 28
R
S
T
Aux
Contact
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SWGR MV DS Procedure Tests
Page | 29
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Disconnector Switch Technical Data (Name Plate)
Manufacturer
Type
Make
Serial No.
Bay No.
Control Voltage
Operation time
Motor Power
Rated Current
Year of Manufacture
2) Test Equipment’s Used:
Note: Used tester types below or approved testers
S.N
Type
Make
1
EGIL
Megger
2
Ohmmeter
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 30
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that disconnector is ready to test and doesn’t have any damage parts
which prevents perfuming tests.
#
TEST DESCRIPTION
REMARKS
(OK / NOT OK)
35. Inspect for any physical damage or defects.
36. Check name plate information for correctness.
37. Check for disconnector switch position indication (open/close)
38. Perform all specific checks as per manufacturer's recommendations.
39. Verify connection as per approved drawing.
40. Check that all grounding cables are securely connected.
Timing Test:
3.2.1) Purpose of test:
- This test is used on medium and high-voltage disconnectors provides
information as to whether the operating mechanism of the disconnector is
operating properly or not by measuring the closing and opening time of the
breaker contacts.
- This test can be used to determine the opening and closing speeds of the
disconnector, the interval time for closing and tripping and the contact
bounce. The test provides information that can be used to detect problems
such as weak accelerating springs, defective shock absorbers, dashpots,
buffers, and closing mechanisms.
- Make sure disconnectors poles at closing and opening position time is
within range of times value of FAT results.
3.2.2) Work Instructions/Test Procedures :
1- Preparing connection of EGIL tester as shown below.
2- Connect external DC supply for closing and tripping coils.
3- Connect wires for closing and tripping coils at schematic DWG.
4- Connect sensing current feedback cable as shown.
Page | 31
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
5- Evaluate results for each sequence and compared it by FAT results.
6- Repeat same sequence at 85% of voltage supply.
➢ Note: This test is performed for GIS/SWG circuit breakers.
➢ Criteria: (As per FAT): Closing ≤6sec, Opening ≤6sec)
Applied Voltage
(V)
Timing (s)
Operation
Close
100% VDC
Open
Close
85% VDC
Open
Page | 32
R
S
T
Aux
Contact
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Contact Resistance Test:
3.1.8) Purpose of test:
- Contact resistance tests are usually performed using a micro/milliohm meter
or a low ohmmeter. The measurement of contact resistance helps to identify
fretting corrosion of contacts and can diagnose and prevent contact
corrosion. An increase in contact resistance can cause a high voltage drop in
the system and needs to be controlled.
- Make sure contact resistance of 3 poles of disconnector switch within range
value of FAT results.
➢ Injected Current: 100A DC.
➢ Criteria: (As per FAT): within +/- 5% of FAT test Reports.
3.1.9) Work Instructions/Test Procedures:
1- Select path for injection current start and end point.
2- Connect cables of ohmmeter tester at selected path.
3- Start test be increase gradually injected current until 100A value.
4- Evaluate results for all selected paths.
5- Compare between measured values and FAT results if accepted.
6- Evaluate all results values and filling down test table formats.
Phase
R
S
T
Page | 33
Result (µΩ)
Remarks
(OK / NOT OK)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
GIS BB Contact Resistance
Procedure Tests
Page | 34
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used
Note: Used tester types below or approved testers by consultant.
S.N
Type
Make
1
Micro-ohmmeter meter
Megger
➢ ALL CALIBRATION CERTIFICATES ARE PROVIDED.
Page | 35
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
Mechanical Check and Visual Inspection:
#
REMARKS
(OK / NOT OK)
TEST DESCRIPTION
41. Inspect bus for physical damage or defects.
42. Check tightness of all bolted connections (torque wrench method).
43. Check quality of paintwork.
44. Check that all grounding cables are securely connected.
Contact Resistance Test:
2.2.1) Purpose of test:
- Measure contact resistance of GIS, SWG busbar to make sure that all joints
are good and no defected parts.
➢ Injected Current: 100A DC
➢ Criteria: (As per FAT): within +/- 5% of FAT test Reports.
➢ Note: this test is performed for GIS/SWG circuit breakers.
2.2.2) Work Instructions/Test Procedures:
1- Select path for injection current start and end point.
2- Connect cables of ohmmeter tester at selected path.
3- Start test be increase gradually injected current until 100A value.
4- Evaluate results for all selected paths for GIS or SWG.
5- Compare between measured values and FAT results if accepted.
#
1
FROM
BAY POINT
BAY
No. of
No. of
bays
bays
Page | 36
TO
POINT
Contact Resistance µΩ
THROUGH
R
S
T
REMARKS
(OK / NOT
OK)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SWGR BB Contact Resistance
Procedure Tests
Page | 37
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used
Note: Used tester types below or approved testers by consultant.
S.N
Type
Make
1
Micro-ohmmeter meter
Megger
➢ ALL CALIBRATION CERTIFICATES ARE PROVIDED.
Page | 38
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
Mechanical Check and Visual Inspection:
#
REMARKS
(OK / NOT OK)
TEST DESCRIPTION
45. Inspect bus for physical damage or defects.
46. Check tightness of all bolted connections (torque wrench method).
47. Check quality of paintwork.
48. Check that all grounding cables are securely connected.
Contact Resistance Test:
2.2.3) Purpose of test:
- Measure contact resistance of GIS, SWG busbar to make sure that all joints
are good and no defected parts.
➢ Injected Current: 100A DC
➢ Criteria: (As per FAT): within +/- 5% of FAT test Reports.
➢ Note: this test is performed for GIS/SWG circuit breakers.
2.2.4) Work Instructions/Test Procedures:
1- Select path for injection current start and end point.
2- Connect cables of ohmmeter tester at selected path.
3- Start test be increase gradually injected current until 100A value.
4- Evaluate results for all selected paths for GIS or SWG.
5- Compare between measured values and FAT results if accepted.
1
CIRCUIT
(BAY – BAY)
K1-1 – K1-2
8
BB Section n
#
Page | 39
R
Contact Resistance µΩ
S
T
REMARKS
(OK / NOT OK)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
GIS HV Procedure Tests
Page | 40
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
Portable UHF PD monitor, PD sensor, Coaxial cable; Noise
sensor or band rejection filter.
2
HV Compartment mobile Car
SIEMENS
Energy
3
Megger
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Additional Safety Precautions:
• Before testing, safety area should be installed around the H.V equipment.
(Clearance: 4m).
• Appropriate display device (Warning light, Warning plate) should be installed to
notify of the testing.
• The customer (or his representative at the substation) shall instruct to the test
personnel on safety work procedures at substation, and safety during its
commissioning, and shall ensure the
obedience.
• Unauthorized persons are not strictly allowed to stay in GIS room during tests.
Page | 41
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
Mechanical and Visual Inspection Test:
TEST #
TEST DESCRIPTION
1.
The resistance of the permanent earthing grid must be
tested.
2.
THE GIS must be filled with the SF6 gas at rated
pressure.
3.
GAS leakage test and moisture content test shall be
performed.
4.
ALL mechanical operation tests of DS, ES and C.B
shall be performed.
5.
Secondary windings of all CT shall be short circuited
and grounded.
6.
Surge arrestor have to be dismantled.
7.
All adjacent portions are insulated and grounded.
8.
9.
10.
VT’S not designed for GIS HV test are removed or
insulated by opening of a disconnector
Power transformers are isolated form the GIS substation
and connected to ground
Test voltage shall be applied from H.V test to GIS via
GAS to air bushing connected to GIS with the wire
covered by corona free shield.
12.
All apparatus of the circuit being tested are in a closed
position.
All grounding switches of the circuit being tested are in
opened position.
13.
Cable boxes are isolated from the substation and connected
to ground.
14.
All work on the substation is interrupted and staff is warned
that a test will be carried out.
11.
Page | 42
Remarks ( OK /
NOT OK )
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Measurement of insulation Resistance Test:
- Between main circuit and earth
2.2.1) Purpose of test:
- Check quality of insulation resistance before performing high pot test and
comparing it by name plate values or FAT results if its accepted.
➢ Applied Voltage: 5000V DC
➢ Criteria: R≥1GΩ as per FAT results.
2.2.2) Work Instructions/Test Procedures:
1- Between main circuit and earth shall be measured by using
5kV Insulation resistance test kit.
2- Before and after high voltage test.
3- All CB & DS → Closed, All ES & VT → Opened
4- Evaluate results on table.
Check Time
Date
Phase
Measured
Value
Result
Acceptance
Norm
R-E
Before HV
S-E
T-E
-5kV -.
More than
1 GΩ
R-E
After HV
S-E
T-E
➢ Note:
- Measurement values may vary depending on the measurement time.
- Namely, Measurement values may vary due to differences in the
moisture of the morning and afternoon.
Page | 43
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
High Voltage and PD (Partial Discharge) Test:
2.3.1) Purpose of test:
- To determine whether the actual condition will be healthy for this designed
GIS. To ensure there is no problem to energize.
- Partial discharge (PD) can occur in medium and high voltage switchgear. PD
represents a breakdown between two conducting electrodes. If PD is not
detected, the damage to the electrical equipment can be catastrophic and cause
serious safety events in the workplace. Partial discharge can easily be
detected by ultrasound and should be part of a routine predictive maintenance
inspection strategy of electrical components.
➢ Acceptance Criteria:
- Shall be withstood (IEC 62271-203).
- The voltage tolerance of HV test is within ±3% (IEC 60060-3)
- In the event of a disruptive discharge occurring during
dielectric tests on site, the tests shall be repeated.
➢ Guidelines on repetition tests:
The guideline is based on recommendations of IEC 62271-203(2003)
standards.
- Annex C 6 of these standards assorts between two kinds of
flashover.
a. Mere gas discharges. In this case the reason is supposed to lie in an
impurity (particle) which burn away during the flash over.
b. Flash overs involving solid insulating material.
- GIS Maker's Policy about disruptive discharge (Flash Over)
1) When disruptive discharge is occurred, the GIS should be visually
inspected all gas compartments.
2) After evacuating the gas, all inspection cover will be opened. Look
for some electrical trace of the solid insulation, enclosure, and main
conductor.
3) Take the necessary action at the fault point, the HV test will be done
again.
Progress procedure:
- Before the visually inspection in the GIS, test voltage injection again
without any modification to the GIS.
- CASE 1
If another F.O takes place at lower voltage level, it is to be assumed
that solid insulation (spacer, insulated rod, post insulator etc.) is
affected. Dividing the test section by disconnector, it can be fined out
the location of disruptive discharge. After repair or replace of the
Page | 44
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
defective solid insulation, HV test is repeated for concerned test
section.
- CASE 2
If the F.O voltage is the same as previous value, check the pole
distance. (DS, ES, CB etc.)
- CASE 3
If the test voltage can be raised to a value above the previous F.O
voltage, as checking the SO2 of the SF6 gas, find out the F.O occurred
section and degas and inspect inside to confirm that the any problem
inside. If there's some electrical trace of the solid insulation, take a
necessary action. If there's no visual defect, we assume that cause for
F.O has been eliminated by itself. HV test is repeated for concerned
test section. (90sec).
2.3.2) Work Instructions/Test Procedures:
1- Prior to performing the GIS EHV/HV Test, calibration of the GIS PD
internal sensor shall first be conducted as per the following Steps:
• Calibration of the GIS PD internal sensor without monitoring system:
- By Use of 3phase unified GIS using internal sensor:
▪ Connect UHF Calibrator to internal UHF sensor and portable
UHF PD monitor to another internal UHF sensor, Spacer, and
noise sensor.
▪ Record the spectrum reading from portable UHF PD monitor.
2- Perform the GIS EHV/HV Test and GIS EHV Partial Discharge Test:
• Connect all Circuit Breakers, disconnector switch, earth switch, and
remove all earthing wires with CT shorted and VT connected to check
the reading of voltage during test.
• Connect EHV/HV tester to GIS as shown below.
Page | 45
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Connect VT during injection EHV/HV.
• According to IEC 62271-101/103 the test value for 220kV GIS is 460kV.
• Site HV test is 80% from standard values, in other words, test value for
220kV GIS is 368kV for one minute (60 sec) or 335kV for 3min.
• We will follow previous IEC standard procedure for voltage step rising
for ensuring the voltage soaking process for gas stabilization for
determined time 3-5 minutes.
• The voltage rising process for 220kV GIS will be as follow:
• Inject voltage at phase R with Y+B connected to Earth as per the
following:
- Rated voltage for 3 mins.
- Increase the voltage gradually up to 1.2 rated voltage for 1min.
- Record the leakage current for GIS EHV/HV Test.
Page | 46
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Decrease the voltage gradually up to rated voltage to perform the GIS
EHV partial discharge test.
• Print the spectrum reading from portable UHF PD monitor or from
mounting system panel if available.
Page | 47
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 48
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• All the test results should be recorded in the test format and check list.
• Repeat above for phase Y and B.
- α: Voltage was applied for the time necessary to perform the
PD measurements in the points on the GIS enclosure. (After
HV Test)
Date
Phase
Section
R
S
T
Page | 49
Standard
Test
Voltage
(kV)
Duration
(Min)
146
220
368
170
146
220
368
170
146
220
368
170
5
3
1
α
5
3
1
α
5
3
1
α
Actual Data
Injection
Voltage
(kV)
Frequency
(Hz)
Current
(A)
Result
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SWGR HV Procedure Tests
Page | 50
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
Megger
Megger
2
HVT-70/50 Tester
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Additional Safety Precautions:
• Before testing, safety area should be installed around the H.V
equipment. (Clearance: 4m).
• Appropriate display device (Warning light, Warning plate) should
be installed to notify of the testing.
• The customer (or his representative at the substation) shall
instruct to the test personnel on safety work procedures at
substation, and safety during its commissioning, and shall ensure
the
obedience.
• Unauthorized persons are not strictly allowed to stay in SWGR room
during tests.
Page | 51
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
Mechanical and Visual Inspection Test:
TEST #
TEST DESCRIPTION
1.
The resistance of the permanent earthing grid must be tested.
2.
ALL mechanical operation tests of ES and C.B shall be performed.
3.
Secondary windings of all CT shall be short circuited and
grounded.
4.
Surge arrestors must be dismantled.
5.
All adjacent portions are insulated and grounded.
6.
VT’S not designed for SWGR HV test are removed or insulated by
opening of a disconnector
7.
Test voltage shall be applied from H.V test to CB Poles with the
wire covered by corona free shield.
8.
All apparatus of the circuit being tested are in a closed position.
9.
All grounding switches of the circuit being tested are in opened position.
10.
Cable boxes are isolated from the substation and connected to ground.
11.
All work on the substation is interrupted and staff is warned that a test
will be carried out.
Page | 52
Remarks ( OK / NOT OK )
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Measurement of insulation Resistance Test:
Between main circuit and earth
2.2.1) Purpose of test:
- Check quality of insulation resistance before performing high pot test
and comparing it by name plate values or FAT results if its accepted.
➢ Applied Voltage: 5000V DC
➢ Criteria: R≥1GΩ as per FAT results.
2.2.2) Work Instructions/Test Procedures:
1- Between main circuit and earth shall be measured by using
5kV Insulation resistance test kit.
2- Before and after high voltage test.
3- All CBs → Closed, All ES & VT → Opened
4- Evaluate results on table.
➢ Section-n High-Voltage Test:
• Insulation Resistance Test: @ 5KV DC for 1 min duration before HV Test:
C.B. Racked in and Closed
Section -1
R –(S+T+G)
S- (R+T+G)
T – (R+S+G)
Insulation Resistance
•
Insulation Resistance Test: @ 5KV DC for 1 min duration After HV Test: C.B.
Racked in and Closed
Section -1
R –(S+T+G)
S- (R+T+G)
T – (R+S+G)
Insulation Resistance
[
➢ Note: Make sure results of insulation resistance after high voltage test
is less than before it.
➢ Note:
- Measurement values may vary depending on the measurement time.
- Namely, Measurement values may vary due to differences in the
moisture of the morning and afternoon.
Page | 53
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
High Voltage Test:
2.3.1) Purpose of test:
- To determine whether the actual condition will be healthy for this
designed switchgear. To ensure there is no problem to energize.
➢ Acceptance Criteria:
- Shall be withstood (IEC 62271-203).
- The voltage tolerance of HV test is within ±3% (IEC 60060-3)
- In the event of a disruptive discharge occurring during
dielectric tests on site, the tests shall be repeated.
2.3.2) Work Instructions/Test Procedures:
1- Circuit Breaker ON, remove all earth wiring and Earth Switch in ON
Position: Inject voltage 3uo (3x rated Voltage/√3) for a duration
of 1 min for Phase R with Y+B earthed. Refer to the below image:
2- Repeat the above Procedure for the remaining 2 phases Y and B.
3- Record the Leakage current for each phase.
4- The measured leakage current should be as per the factory test value.
5- Evaluate results of HV values and leakage current.
6- Filing all results on test format tables.
Page | 54
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
•
HV Test by AC HV Testers for 60 Sec Duration: 1st C.B. is racked in and
closed and al CBs of section are Racked in and Open Position
Phase Applied Voltage
Leakage
Current (mA)
Duration
R
S
40 KV
60 Sec
T
•
HV Test by AC HV Testers for 60 Sec Duration: 1st C.B. is racked in and
closed and al CBs of section are Racked in and Closed Position
Phase Applied Voltage
Leakage
Current (mA)
Duration
R
S
40 KV
60 Sec
T
➢ Note: Make sure results of leakage current values when CB s are
opened less than which are closed.
2- After we finish HV test at selected values, we connected VT by
fuses and inject rated voltage of SWGR value.
3- Measure values of voltage at digital meters and protection relays.
4- Evaluate results and filling it on test tables.
Phase
R-N
S-N
T-N
Page | 55
Measured Point Location
Measured
Voltage (V)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SWGR Mechanical Interlock
Procedure Test
Page | 56
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used
S.N
Type
Make
1
SWGR tools for ES, CB, DS
SWGR Manufacture
Calibration date
2) TESTS:
Mechanical Interlock Check:
2.1.1) Purpose of test:
- Mechanical testing is very important to verify that SWGR mechanical parts
work together properly and all switchgear parts work properly during daily
operation.
- Make sure that mechanical interlock between electrical compartments meet
FAT and operation requirements.
2.1.2) Work Instructions/Test Procedures:
1- Check for any defected parts of compartments before starting any type
of testes on it.
2- Check for all interlock conditions between circuit breaker and earth
switch or disconnectors to make sure every compartment work
properly.
3- Check for test and service positions of circuit breaker.
4- Evaluate any defected part of compartment and record it on test format
tables as shown below:
Checked
#.
ES
OK/NOT OK
1
ES CLOSE: Check C.B cannot rack in.
2
ES CLOSE: Check can open Rear door and front door.
3
ES OPEN: Check cannot open Rear door and front door.
4
ES OPEN: Check ES emergency front door.
5
ES OPEN: Check ES emergency rear door.
Page | 57
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Checked
#.
C.B
OK/NOT OK
1
In service position CB door is locked.
2
In test position CB door is open.
3
CB can't operate in middle traveling position.
4
Can’t Rack C.B in or out while CB closed, or door is open.
5
ES cannot operate while CB in service.
6
Check CB emergency trip.
7
Check CB emergency door in service position.
#
VT
Checked
OK/NOT OK
1
VIS with front door and rear door (Can’t open)
2
VT truck with VT panel door
3
VT truck rack in and rack out positions
4
VT emergency door while in service.
5- Repeat this step for all bays of SWGR or GIS.
Page | 58
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
GIS Mechanical Interlock
Procedure Test
Page | 59
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used
S.N
Type
Make
1
SWGR tools for ES, CB, DS
SWGR Manufacture
Calibration date
2) TESTS:
Mechanical Interlock Check:
2.1.1) Purpose of test:
- Mechanical testing is very important to verify that SWGR mechanical parts
work together properly and all switchgear parts work properly during daily
operation.
- Make sure that mechanical interlock between electrical compartments meet
FAT and operation requirements.
2.1.2) Work Instructions/Test Procedures:
1- Check for any defected parts of compartments before starting any type
of testes on it.
2- Check for all interlock conditions between circuit breaker and earth
switch or disconnectors to make sure every compartment work
properly.
3- Check for test and service positions of circuit breaker.
4- Evaluate any defected part of compartment and record it on test format
tables as shown below:
Bay No:
Checked
#.
ES/DS
OK/NOT OK
1
Q51
2
Q52
3
Q53
4
Q1
5
Q2
Page | 60
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Checked
#.
C.B
OK/NOT OK
1
Spring Charging
2
Operation
5- Repeat this step for all bays of SWGR or GIS.
Page | 61
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Surge Arrestor Procedure
Test
Page | 62
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Surge Arrestor (Name Plate)
Manufacturer
Model No.
Rated Voltage
Rated Frequency
MCOV
Serial No.
LD Class
System Voltage
PR Relief Current
2) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
Megger
Megger
2
CPC 100
OMICRON
3
CP TD 12/15
OMICRON
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 63
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical and Visual Inspection Test:
#
DESCRIPTION
1.
Inspect for physical damage / defects.
2.
Check tightness of all bolted connections (torque wrench method).
3.
For multi-unit stacks, check that the physical arrangement of the
units are erected according to the manufacturer’s specifications.
4.
Check that all grounding cables are correctly and secured connected.
5.
Verify Meter as per approved drawings.
6.
Check name plate information for correctness as per SEC’s
specifications.
7.
Check that impulse counter and leakage current meter glasses are not
broken or cracked.
Page | 64
CHECKED
(OK / NOT OK)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Insulation Resistance Test:
3.2.1) Purpose of test:
- To determine the equipment in proper condition to put in service. Results
can be kept as record to compare in future and to understand the trend of
insulation during maintenance.
➢ Applied Voltage: 5000V DC
3.2.2) Work Instructions/Test Procedures:
1- Thoroughly clean all Bushings of the surge arresters to be tested.
2- Connect megger tester as shown below.
3- Perform Insulation Resistance Testing with injected DC voltage of
5kV as per the following test connections.
4- Repeat previous steps for phases B and C.
5- Evaluate test results and compare it by FAT results.
Phase
R
S
T
Page | 65
Measured Value (GΩ)
Remarks
(OK / NOT OK)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
loss factor tan δ and capacitance C Test:
3.3.1) Purpose of test:
- The main purpose of the tan delta test is to make sure of maintaining a
secure and reliable functioning of the transformer. With the calculation of
dissipation factor and capacitance values, it provides the result of
insulation behavior of bushings and in windings too.
- Variation in the capacitance value, for instance, it indicates partial kind of
breakdowns in bushings and automated movement of windings. Insulation
deprivation, aging of the equipment, enhancement in the energy levels is
transformed into heat. The number of losses in these is calculated as the
dissipation factor.
- All modern bushings rated 23 kV and higher have a power factor, or
capacitance tap which permits dissipation factor testing of the bushing
while it is in place on the apparatus without disconnecting any leads to the
bushing. The dis-septation factor is measured by the ungrounded specimen
test (UST) which eliminates the influence of transformer winding
insulation, breaker arc-interrupters, or support structures which are
connected to the bushing terminal.
➢ Criteria: The acceptance criteria for field tests that the measured value
doesn’t exceed 0.5% according to FAT.
➢ Using our CP TD12 respectively CP TD15 combined with
TESTRANO 600 or CPC 100/80, you can determine a wide range of
electric and dielectric parameters:
• Power factor (cos φ) / dissipation factor (tan δ).
• Capacitance.
• Exciting current.
3.3.2) Work Instructions/Test Procedures:
1- Connect CPC100 by CP TD 12/15 Unit as shown below.
2- Apply 10kV Test voltage from CPC100 kit screen.
3- Connect test ground to apparatus ground.
4- Connect the high-voltage lead to the terminal at the top of the bushing
and the low-voltage lead (red) to the power factor tap.
5- Ground the apparatus tank. The tap is normally grounded through a
spring, and it is necessary,
Page | 66
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
6- when making measurements, to remove the plug which seals and
grounds the tap. Use the UST measure red, ground blue test mode
setting (UST-R).
7- Perform the Dissipation Factor (tan δ) test as per the below test
connections:
PHASE
R
S
T
Page | 67
Test Voltage
(kV)
Capacitance
(nF)
DF%
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
GIS Primary Injection
Procedure Test
Page | 68
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: Used ODEN Tester for primary injection at GIS Busbar because
high load impedance and we need high injected current.
S.N
Type
Make
1
ODEN
Megger
2
Clamp meter
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
- Use series connection when you want a high voltage at a high load impedance.
- Use parallel connection when you need a low internal impedance to be able to
generate high current.
Page | 69
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
Primary Injection Test
2.1.1) Purpose of test:
- Primary injection test is to ensure the CT circuits are properly
connected with respected cores and there is no mix up in the circuits
(phase identification).
2.1.2) Work Instructions/Test Procedure:
- Core Identification Test:
• In this test we confirm the CT secondary connection.
• Inject low current (for example:50A).
• Use small jumper to short CT secondary from CT box, the
measurement will be gone at panel.
• Repeat this test for all phases and cores.
- Short and isolate facility Test:
• We confirm the CT short and isolate facility for correct
connection.
• Inject low current (for example:50A).
• Short CT links then isolate the external wiring to confirm CT
circuit will not be opened.
- Single earth point (SEP) Test:
• For all CT loops, each CT loop must have one (SEP), otherwise
secondary current will be divided.
• Open earth point and check with buzzer that there is no earth link
is closed, then close on point.
- Primary injection Test:
• After confirming all previous steps, CT is ready now to the
primary injection test.
• Choose two points to connect two terminals of ODEN Cables.
• Make sure chosen closed path has two specified CTs to check
them.
• Use ODEN kit to inject current.
• Measure the secondary current in all loop up to the end of this
loop.
Page | 70
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ INJECTED PRIMARY CURRENT (
• CORE-1: Protection Core:
Phase
R
S
T
N
Page | 71
Terminal
NO.
Injected
Current (A)
Terminal
NO.
)A
Measured
Current (A)
Terminal
NO.
Measured
Current (A)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SWGR Primary Injection
Procedure Test
Page | 72
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: Used CPC 100 Tester for primary injection at SWG because is less
than ODEN in weight or used another approved tester.
S.N
Type
Make
1
CPC 100 +Current Booster CB2
OMICRON
2
Clamp meter
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
- For primary injection by CPC 100,you need external booster (CB2)
which connected to CPC 100 kit as shown in figure below
Page | 73
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
Primary Injection Test
2.1.1) Purpose of test:
- Primary injection test is to ensure the CT circuits are properly connected
with respected cores and there is no mix up in the circuits (phase
identification).
2.1.2) Work Instructions/Test Procedure:
- Core Identification Test:
• In this test we confirm the CT secondary connection.
• Inject low current (for example:50A).
• Use small jumper to short CT secondary from CT box, the
measurement will be gone at panel.
• Repeat this test for all phases and cores.
- Short and isolate facility Test:
• We confirm the CT short and isolate facility for correct
connection.
• Inject low current (for example:50A).
• Short CT links then isolate the external wiring to confirm CT
circuit will not be opened.
- Single earth point (SEP) Test:
• For all CT loops, each CT loop must have one (SEP), otherwise
secondary current will be divided.
• Open earth point and check with buzzer that there is no earth link
is closed, then close on point.
- Primary injection Test:
• After confirming all previous steps, CT is ready now to the primary
injection test.
• Choose two points to connect two terminals of ODEN Cables.
• Make sure chosen closed path has two specified CTs to check them.
• Use CPC100+Booster with connection is shown below kit to inject
current.
• Select one of two modes:
- 1000A mode
- 2000A mode
Page | 74
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Measure the secondary current in all loops up to the end of this loop.
➢ INJECTED PRIMARY CURRENT (
• CORE-1: Protection Core:
Phase
R
S
T
N
Page | 75
Terminal
NO.
Injected
Current (A)
Terminal
NO.
)A
Measured
Current (A)
Terminal
NO.
Measured
Current (A)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Current Transformers
CT Procedure Tests
Page | 76
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Current Transformer Technical Data (Name Plate)
Manufacturer
Model No.
Bay No.
Rated Frequency
50 Hz
Burden
Class
Ratio
Core 1
Core 2
Core 3
Core 4
2) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
Megger 5K VDC
Megger
2
OMICRON CT Analyzer
OMICRON
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 77
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that current transformer is ready to test and doesn’t have
any damage parts which prevents perfuming tests.
#
TEST DESCRIPTION
1.
Inspect for physical damage or defects.
2.
Check nameplate information for correctness.
4.
Check that outdoor secondary wiring terminations are installed in moisture
proof enclosures.
Check tightness of all bolted connections (torque wrench method).
5.
Check that all grounding cables are securely connected.
6.
Check secondary wiring is correctly color coded and size of wires is as
specified.
7.
Check proper lugs have been used on terminations.
8.
Check CT locations physically and secondary terminal labeling has been
done correctly.
3.
REMARKS
(OK / NOT OK)
3.1) Insulation Resistance Test:
3.2.1) Purpose of test:
- To determine the equipment in proper condition to put in service.
Results can be kept as a record to compare in future and to understand
the trend of insulation during maintenance.
➢ Applied Voltage:
• 5000V DC for Primary – Earth.
• 2500V DC for Primary – Secondary.
• 1000V DC for Secondary - Secondary & Secondary - Earth
➢ Criteria:
As per FAT): More than 2500 MΩ for Primary – Secondary – Earth
More than 2000 MΩ for Secondary - Earth and between secondaries.
➢ Note: This test is performed for GIS/SWG current transformer.
Page | 78
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.2.2) Work Instructions/Test Procedure:
1- Connect megger tester as shown below.
2- Apply voltage test value for each connection.
3- Make sure CT secondaries earth connection are disconnected.
4- Make sure GIS/SWG is earthed successfully.
5- Evaluate test results and compare it by FAT results.
Phase: n
Primary
Earth
Core 1
Core 2
Core 3
Core 4
Primary - Earth
Page | 79
Core 1
Core 2
Core 3
Core 4
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Winding Resistance Test:
3.3.1) Purpose of test:
- Secondary resistance test is to verify the CT secondary winding
resistance with specified one and no discontinuity in the winding.
- Make sure measured value doesn’t affect on knee voltage value of
current transformer.
➢ The Resistance card is only available if winding resistance
measurement is enabled in the Select Cards page (Default Test Card
Selection or Select Cards soft key in the CT-Object card).
➢ Depending on your selection on the Select Cards page, the
Resistance card shows the parameters and results for the primary
winding resistance measurement or the secondary winding
resistance measurement only, or for both measurements.
Page | 80
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Criteria: within +/- 5% of FAT test Reports
➢ Note: CT Analyzer by OMICRON tester is used for all tests of current
transformer.
3.3.2) Work Instructions/Test Procedure:
1- Connect CT to CT Analyzer kit as shown in figure below.
2- Make sure terminal slide of secondary wiring is opened.
3- Choose the below tests from tester window.
4- Evaluate results as software file report which is printed later to
attached with main test report.
5- Compare measured values with FAT results.
Page | 81
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Turns Ratio-Polarity Test:
3.4.1) Purpose of test:
- Ratio test is to ensure the turns ratio of the all the taps.
- Make sure polarity of CT is OK for performing succeed stability test.
➢ Criteria: (As per FAT Results).
➢ The Ratio card is only available if it is enabled in the Select Cards
page (Default Test Settings or Select Cards soft key in the CTObject card).
➢ The ratio test measures the current ratio of the CT considering the
operating burden (parameter "Burden" in CT-Object card) or the
nominal burden (parameter "VA" in CT-Object card).
➢ For a better understanding of the test results, the most important
settings from the CT-Object card are shown once again in the upper
part of the Ratio card.
➢ Note: Although the test is not performed with the real current, the
test results reflect the current ratio and not the voltage ratio.
➢ Note: Although the test is not performed with the real current, the
test results reflect the current ratio and not the voltage ratio.
Page | 82
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.4.2) Work Instructions/Test Procedure:
1- Connect CT to CT Analyzer kit as shown in figure below.
2- Make sure terminal slide of secondary wiring is opened.
3- Choose the below tests from tester window.
4- Evaluate results as software file report which is printed later to
attached with main test report.
5- Compare measured values with FAT results
Excitation Curve Test:
3.5.1) Purpose of test:
- Mag curve test is to confirm the magnetization characteristics of CT.
- Calculate knee voltage point for current transformer which CT
enter saturation region after this point.
➢ The excitation graph page shows the graph calculated from the test
results.
➢ To display the excitation graph, press the Exist. Graph soft key in the
Excitation card. The graph shows the r.m.s. terminal/core voltage
over the r.m.s./peak current depending on the selected standard.
➢ Criteria: The %age error for Magnetizing current shall be within
+/-5% of the factory Test.
➢ ALL OMICRON CT ANALYZER REPORTS ARE PROVIDED.
➢ ALL FAT REPORTS ARE PROVIDED.
Page | 83
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.5.2) Work Instructions/Test Procedure:
1- Connect CT to CT Analyzer kit as shown in figure below.
2- Make sure terminal slide of secondary wiring is opened.
3- Choose the below tests from tester window.
4- Evaluate results as software file report which is printed later to
attached with main test report.
5- Compare measured values with FAT results.
Burden Test:
3.6.1) Purpose of test:
- Calculate secondary winding connected burden (VA) and compare it
by name plate values or FAT results.
- Calculate resistance of secondary winding of current transformer and
compare it by name plate values or FAT results.
➢ The Burden card is only available if it is enabled on the Select Cards
page
(Default Test Card Selection or Select Cards soft key in the CT-Object
card).
➢ Using the Burden card, a current transformer’s secondary burden
impedance can be measured with the selected secondary current (Isn) at
nominal frequency.
➢ If a current other than Isn should be used to test the burden, the desired
test current can be entered in the "I-test" parameter field.
Page | 84
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.6.2) Work Instructions/Test Procedure:
1- Connect CT to CT Analyzer kit as shown in figure below.
2- Make sure terminal slide of secondary wiring is opened.
3- Choose the below tests from tester window.
4- Evaluate results as software file report which is printed later to
attached with main test report.
5- Compare measured values with FAT results
Page | 85
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
CT Loop Procedure Test
Page | 86
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Current Transformer Technical Data (Name Plate)
Manufacturer
Model No.
Bay No.
Rated Frequency
50 Hz
Burden
Class
Ratio
Core 1
Core 2
Core 3
Core 4
2) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
FREJA 300
Megger
2
Multi-Ammeter
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 87
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Secondary Loop current Injection Test:
3.1.1) Purpose of test:
- Check the CTS’ protection and metering cores loops continuity.
- Make sure all injected values are corrected at metering and protection
devices.
➢ Criteria: As per FAT): %error accuracy of metering and protection core.
3.1.2) Work Instructions/Test Procedure:
1- Make sure CT terminal block slide is opened to inject secondary loop.
2- Connect 4 wire of FREJA tester for 4 points of CT from schematic
DWG.
3- Make sure that one specified (SEP) single earth point.
4- Measure the secondary current in all loops up to the end of this loop.
5- Inject different values of current to make sure no swape between
external cores of cable.
6- Evaluate test results and compare it by FAT results.
Page | 88
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Phase
Terminal
NO.
Injected
Current (A)
Terminal
NO.
Measured
Current (A)
Terminal
NO.
Measured
Current (A)
0.25 ∟0▪
0.5 ∟240▪
0.75 ∟120▪
0.43
R
S
T
N
Loop Resistance and Burden Test:
3.2.1) Purpose of test:
- Calculate external loop resistance and connected load burden with CT.
- Make sure measured values are within range of name plate data or FAT
results.
➢ Criteria: As per Name Plate Data): value of CT Burden.
3.2.2) Work Instructions/Test Procedure:
1- Inject 1A from FREJA tester for all phases.
2- By using multimeter measure voltage of each core for each phase.
3- Compare measured values with name plate data if accepted.
4- Repeat this step for all phases with all cores.
Phase R
Core
ZR(Ω)
Burden (VA)
Phase Y
ZS(Ω)
Burden (VA)
Phase B
ZT(Ω)
Burden (VA)
Core 1
Core 2
Core 3
Core 4
➢ For Burden Check we inject rated current (1A) and then measure VA for
each single phase.
Page | 89
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Voltage Transformers
VT Procedure Tests
Page | 90
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Voltage Transformer Technical Data (Name Plate)
Manufacturer
Model No.
Bay No.
Rated Frequency
Ratio
Burden
Class
Phase R
Phase S
Phase T
Core 1
Core 2
Core 3
Serial No.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
Megger 5K VDC
Megger
2
CPC 100
OMICRON
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 91
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that voltage transformer is ready to test and doesn’t have any
damage parts which prevents perfuming tests.
REMARKS
#
TEST DESCRIPTION
(OK / NOT OK)
1.
Inspect for physical damage or defects.
2. Check nameplate information for correctness.
3. Check tightness of all bolted connection.
Check that the HV connection does not transfer stress to the HV
4. terminal.
5. Check that all grounding cables are securely connected.
Check mechanical clearances and proper operation of all isolation and
6. grounding devices (as applicable).
7. Check integrity of primary fuses (if applicable).
8. Check insulation liquid level (if applicable).
Insulation Resistance Test:
3.2.1) Purpose of test:
- To determine the equipment in proper condition to put in service. Results
can be kept as record to compare in future and to understand the trend of
insulation during maintenance
➢ Applied Voltage:
• 5000V DC for Primary – Earth.
• 2500V DC for Primary – Secondary.
• 1000V DC for Secondary - Secondary & Secondary - Earth
➢ Criteria:
As per FAT): More than 2500 MΩ for Primary – Secondary – Earth
More than 2000 MΩ for Secondary - Earth and between secondaries.
Page | 92
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Note: This test is performed for GIS/SWG voltage transformer.
3.2.2) Work Instructions/Test Procedure:
1- Connect megger tester as shown below.
2- Apply voltage test value for each connection.
3- Make sure VT secondaries earth connection are disconnected.
4- Make sure GIS/SWG is earthed successfully.
5- Evaluate test results and compare it by FAT results.
Core 1
Primary
Earth
Core 1
Core 2
Core 3
Primary – Earth
Page | 93
Core 2
Core 3
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Winding Resistance Test
3.3.1) Purpose of test:
- Winding resistance test is to verify the PT primary and secondary have no
discontinuity or abnormal in the winding.
➢ Criteria: within +/- 5% of FAT test Reports
➢ Note: CT Analyzer by OMICRON tester is used for all tests of current
transformer.
3.3.2) Work Instructions/Test Procedure:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Identify test parameters and terminals for proper connections.
3- Set-up and effectively ground the test instrument. Supply voltage,
110Vac or 230Vac. Conduct testing as per the following illustrated test
Connections:
Page | 94
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
4- Power ON the Test Instrument and select R-Winding Test Card.
5- Properly fill-up test settings:
6- Press I/O (test start/stop) push-button to start the test.
7- Save test card for printing.
For multi-tap core/s, create and save test card for each tap tested.
8- Note and record all necessary test parameters
9- Evaluate test result as per general standard ratings and accuracy
classes for Voltage transformers.
Phase R (mΩ)
Phase S (mΩ)
Phase T (mΩ)
Core 1
Core 2
Core 3
➢ ALL FAT REPORTS ARE PROVIDED.
Polarity Check Test:
3.4.1) Purpose of test:
- Make sure that polarity is ok for all cores of VT to avoid maloperation of
protection relays or metering devices.
➢ Criteria: Polarity is OK.
3.4.2) Work Instructions/Test Procedure:
1- Setup the CALIBRATED test instrument in a firm, reasonably level base
and dry area.
2- Identify test parameters and terminals for proper connections.
3- Set-up and effectively ground the test instrument. Supply voltage,
110Vac or 230Vac. Conduct testing as per the following illustrated test
Connections:
Page | 95
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
4- Power ON the Test Instrument and select Polarity Test Card.
5- Properly fill-up test settings:
6- Press I/O (test start/stop) push-button to start the test.
7- Save test card for printing.
For multi-tap core/s, create and save test card for each tap tested.
8- Note and record all necessary test parameters
9- Evaluate test result as per general standard ratings and accuracy
classes for Voltage transformers.
Phase R
Phase S
Phase T
Core 1
(OK / NOT OK)
(OK / NOT OK)
(OK / NOT OK)
Core 2
(OK / NOT OK)
(OK / NOT OK)
(OK / NOT OK)
Core 3
(OK / NOT OK)
(OK / NOT OK)
(OK / NOT OK)
Turns Ratio Error Test:
3.5.1) Purpose of test:
- Calculate turns ratio of VT to make sure that VT is achieved requirements for
protection and metering.
➢ Criteria: The %age error for Ratio test shall be within +/-0.5% of FAT
results.
➢ ALL FAT REPORTS ARE PROVIDED.
3.5.2) Work Instructions/Test Procedure:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Identify test parameters and terminals for proper connections.
3- Set-up and effectively ground the test instrument. Supply voltage,
110Vac or 230Vac. Conduct testing as per the following illustrated
test Connections:
Page | 96
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
4567-
Power ON the Test Instrument and select VT Ratio Test Card.
Properly fill-up test settings:
Press I/O (test start/stop) push-button to start the test.
Save test card for printing.
For multi-tap core/s, create and save test card for each tap tested.
8- Note and record all necessary test parameters.
9- Evaluate test result as per general standard ratings.
Calculated
ratio
Phase R
Measured
ratio
Core 1
Core 2
Core 3
Page | 97
Ratio
Error
(%)
Phase S
Measured
ratio
Ratio
Error
(%)
Phase T
Measured
ratio
Ratio
Error
(%)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Burden Test:
3.1.10) Purpose of test:
- Calculate secondary winding connected burden (VA) and compare it
by name plate values or FAT results.
- Calculate resistance of secondary winding of current transformer and
compare it by name plate values or FAT results.
➢ The Burden card is only available if it is enabled on the Select Cards
page
(Default Test Card Selection or Select Cards soft key in the CT-Object
card).
➢ Using the Burden card, a current transformer’s secondary burden
impedance can be measured with the selected secondary current (Isn) at
nominal frequency.
➢ If a current other than Isn should be used to test the burden, the desired
test current can be entered in the "I-test" parameter field.
3.1.11)
1234-
Work Instructions/Test Procedure:
Connect CT to CT Analyzer kit as shown in figure below.
Make sure terminal slide of secondary wiring is opened.
Choose the below tests from tester window.
Evaluate results as software file report which is printed later to attached
with main test report.
5- Compare measured values with FAT results
Page | 98
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
VT Loop Procedure Test
Page | 99
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Voltage Transformer Technical Data (Name Plate)
Manufacturer
Model No.
Bay No.
Rated Frequency
Ratio
Burden
Class
Phase R
Phase S
Phase T
Core 1
Core 2
Core 3
Serial No.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S. N
Type
Make
1
FREJA 300
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 100
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Secondary Loop Voltage Injection Test:
3.1.1) Purpose of test:
- Check the VTS’ protection and metering cores loops continuity.
- Secondary injection test is to verify the VT wiring connected properly to
the load and there is no discontinuity and all the VT ratio setting set inside
the protection devices are correct.
➢ Criteria: As per FAT): %error accuracy of metering and protection core.
3.1.2) Work Instructions/Test Procedures :
1- Make sure VT terminal block slide is opened to inject secondary loop.
2- Connect 4 wire of FREJA tester for 4 points of VT from schematic DWG.
3- Make sure that one specified (SEP) single earth point.
4- Measure the secondary voltage in all loop up to the end of this loop.
5- Inject different values of voltage to make sure no swape between
external cores of cable.
6- Evaluate test results and compare it by FAT results.
Bay:
Bay:
Bay:
Phase
Terminal
NO.
R
S
T
Page | 101
Injected Voltage
(V)
(0.25Vr) =14.4
(0.5Vr) =28.9
(Vr)=57.73
Terminal
NO.
Measured
Voltage (V)
Terminal
NO.
Measured
Voltage (V)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Power Transformers
Procedure Tests
Page | 102
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Transformer Technical Data (Name Plate)
- For example: this name plate for power transformer installed at Traction_2 SS
-
Page | 103
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers by consultant.
S.N
Type
Make
1
Megger 5K VDC
Megger
2
CPC 100
OMICRON
3
Diesel Generator
PREDATOR
4
Multimeter + Clamp meter
Megger
5
CP TD 12/15
OMICRON
6
FRAX99 – Sweep Frequency Response
Analysis
7
Microcal T500
8
ZWJD111
Megger
Euro Tron
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 104
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that transformer is ready to test and doesn’t have a damage part
which prevents perfuming tests.
#
TEST DESCRIPTION
REMARKS
(OK / NOT OK)
Inspect for physical damage/defects (see for any cracks, chips, etc. on
49. visible outer layer of the cast resin).
50. Check nameplate for correctness.
51. Check tightness of all bolted connections (torque wrench method).
Check that all grounding is securely connected, including star point
52. neutral.
53. Perform all specific checks per manufacturer instructions
54. Check proper operation of all auxiliary devices (if applicable)
Polarization Index Test:
3.2.1) Purpose of test:
- Check quality of winding insulation resistance before performing high
pot test and comparing it by name plate values or FAT results if its
accepted.
- Check for all connections as shown below.
➢ Applied Voltage: 2500/5000V DC
➢ Criteria: PI > 1.25
POLARIZATION INDEX (PI) =
10 min Insulation resistance (Meg−ohm) reading
1 min Insulation resistance (Meg−ohm) reading
≥ 1.25.
3.2.2) Work Instructions/Test Procedures :
1- Connect megger tester as shown below.
2- Apply voltage test value for each connection.
3- Evaluate test results and compare it by FAT results.
4- Calculate PI value for each connection and make sure that more than
criteria value.
Page | 105
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1)HV-LV winding insulation
resistance test
2)HV winding-Ground insulation
resistance test
3)LV winding-Ground
insulation resistance test
4)Core-Frame insulation
resistance test
5)Frame-Earth insulation
resistance test
6)Core-Earth insulation
resistance test
Winding Under
Test
HV – E
HV – LV
LV- E
Core + Clamp
Core – E
Clamp – E
Page | 106
Test Voltage
(kV)
Results after
60 Seconds
Results after
600 Seconds
PI
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Turns-Ratio (TTR) Test:
3.3.1) Purpose of test:
- Ratio test is used to make sure that the ratio between the windings of the
primary and secondary coils follow the proper specifications.
- This test ensures that the transformer will provide the proper step down in
voltage.
➢ The CPC 100 tester is used or any approved suitable tester, the turns-ratio test
can be performed by two types of connections (1-PH or 3-PH) connections
which are available at site and approved, we use 1st connection.
➢ Criteria: The acceptance criteria for field tests that the range of measured
ratio shall be equal to the calculated ration ±0.5 %.
1) Single-Phase Test Connection: CPC 100 only with a maximum output voltage
of 2000V.
2) Three-Phase Test Connection: CPC 100 + CP SB1 with a maximum output
voltage of 300V.
3.3.2) Work Instructions/Test Procedures :
1- Connect CPC100 connections as shown below.
2- Apply selected test type from CPC100 window.
3- Connect primary winding connections and be careful during test.
4- Evaluate results during each tap.
Page | 107
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Tap Voltage
Tap
H.V
LV
Measured Value
Cal.
Ratio
Ratio
Error
%
(mA)
Ratio
Error
%
(mA)
Ratio
Error
%
(mA)
No. of
Taps
DC Winding Resistance Test:
3.4.1) Purpose of test:
- The purpose of measuring the DC winding resistance of the transformer
windings is to check the welding quality of the winding joints and whether the
windings have short circuits between the windings, whether the contact
positions of the voltage tap switches are good and whether the actual positions
of the taps match, whether there is a break in the lead wires or not.
➢ The CPC 100 is required or any approved tester. Before beginning the DC
Winding Resistance test, please consider the following,
➢ The DC Winding Resistance Test should always be the last test performed on
a power transformer.
➢ The DC Winding Resistance test can be performed with the CPC 100 or
another approved tester using three methods, which include:
• 400A DC Method – Recommend for measuring resistances < 50mΩ and
(e.g. typically useful for performing a low-voltage winding resistance
measurement)
• 6A DC Method – Recommended for measuring resistances > 50mΩ and
<10Ω (e.g. typically useful for performing a high-voltage winding
resistance measurement).
• 2-Wire Method – Recommended for measuring resistances >10Ω only.
➢ Note: make sure that each phase results must same as other phases within %error.
Page | 108
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.4.2) Work Instructions/Test Procedures :
1- Connect CPC100 connections as shown below.
2- Apply selected test type from CPC100 window.
3- Connect primary winding connections and be careful during test.
4- Repeat this step for all phases at all number of taps.
5- Evaluate results during each tap.
➢ High Voltage Side Winding Resistance:
➢ Criteria: As per FAT Results.
➢ Ambient Temperature: 28ᵒC
RN (Ω)
TAP #
SN (Ω)
TN (Ω)
No. of taps
➢ Low Voltage Winding Resistance:
➢ Criteria: As per FAT Results.
➢ Ambient Temperature: 28ᵒC
rs (mΩ)
Page | 109
st (mΩ)
tr (mΩ)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
loss factor tan δ and capacitance C of the winding Test:
3.5.1) Purpose of test:
- The main purpose of the tan delta test is to make sure of maintaining a
secure and reliable functioning of the transformer. With the calculation
of dissipation factor and capacitance values, it provides the result of
insulation behavior of bushings and in windings too.
- Variation in the capacitance value, for instance, it indicates partial kind
of breakdowns in bushings and automated movement of windings.
Insulation deprivation, aging of the equipment, enhancement in the
energy levels is transformed into heat. The number of losses in these is
calculated as the dissipation factor.
- With the tan delta testing method, one can easily know the dissipation
factor and the capacitance values at the required level of frequencies.
So, any kind of aging factor can be identified earlier, and the
corresponding action can be implemented.
➢ Criteria: The acceptance criteria for field tests that the measured value
doesn’t exceed 0.5% according to FAT.
3.5.2) Work Instructions/Test Procedures:
1- A Tan Delta test is performed by applying an ac voltage to a test cell
of known gap, measuring the total current flow through the oil, and
separating and comparing the reactive and resistance portions of the
current passing through the oil.
2- Connect CPC100 by CP TD 12/15 Unit as shown below.
3- Short Circuit each winding of the transformer at its bushing terminals and
connect all windings to ground except the winding to be measured.
4- Apply 10kV Test voltage from CPC100 kit screen.
5- Apply all test for all connections are mentioned in table below.
Page | 110
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Insulation
type
Test
Mode
HV/LV+G
GST
HV+LV/G
GST
LV/HV+G
GST
HV/LV
UST
Page | 111
Test
Voltage
(kV)
Capacitance
(nF)
Leakage
Current
(mA)
Tan Delta @ 30ᵒC
Tan δ = (IR /IC)
Tan Delta @ 20ᵒC
Tan δ = (IR /IC)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 112
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
loss factor tan δ and capacitance C of the Bushing Test
3.5.3) Purpose of test:
- The main purpose of the tan delta test is to make sure of maintaining a
secure and reliable functioning of the transformer. With the calculation
of dissipation factor and capacitance values, it provides the result of
insulation behavior of bushings and in windings too.
- Variation in the capacitance value, for instance, it indicates partial kind
of breakdowns in bushings and automated movement of windings.
Insulation deprivation, aging of the equipment, enhancement in the
energy levels is transformed into heat. The number of losses in these is
calculated as the dissipation factor.
- All modern bushings rated 23 kV and higher have a power factor, or
capacitance tap which permits dissipation factor testing of the bushing
while it is in place on the apparatus without disconnecting any leads to
the bushing. The dis-septation factor is measured by the ungrounded
specimen test (UST) which eliminates the influence of transformer
winding insulation, breaker arc-interrupters, or support structures
which are connected to the bushing terminal.
➢ Criteria: The acceptance criteria for field tests that the measured value
doesn’t exceed 0.5% according to FAT.
3.5.4) Work Instructions/Test Procedures:
1- A Tan Delta test is performed by applying an ac voltage to a test cell of
known gap, measuring the total current flow through the oil, and separating
and comparing the reactive and resistance portions of the current passing
through the oil.
2- Connect CPC100 by CP TD 12/15 Unit as shown below.
3- Apply 10kV Test voltage from CPC100 kit screen.
4- Connect test ground to apparatus ground.
5- Connect the high-voltage lead to the terminal at the top of the bushing
and the low-voltage lead (red) to the power factor tap.
6- Ground the apparatus tank. The tap is normally grounded through a
spring, and it is necessary,
7- when making measurements, to remove the plug which seals and
grounds the tap. Use the UST measure red, ground blue test mode
setting (UST-R).
Page | 113
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
8- Apply all test for all phases are mentioned in table below.
9- Evaluate results and check if it accepted.
- Connection of UST
mode for Bushing
insulation test.
- This kit connection for
illustration only.
HV
Insulation type
Test Mode
Test Voltage (kV)
Tan Delta %
N
10
R
10
UST-A
S
10
T
10
Page | 114
Capacitance (pF)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Zero sequence impudence Test
3.5.5) Purpose of test:
- The purpose of this test is to measure the zero-sequence impedance for
all-star connected windings of the transformer needed for earth fault
protection and earth fault current calculations.
3.5.6) Work Instructions/Test Procedures:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Thoroughly clean all Bushings of the Transformer to be tested.
3- Identify test parameters and terminals for proper connections.
4- Conduct testing as per the following illustrated test Connections:
• Test Connection with HV Winding Shorted.
• Record the Measured Current (Im) and Measured Voltage (Vm) at
first, middle and last tap.
• Calculate the Zero Sequence Impedance Percentage error by using
the formula:
Z% =
Page | 115
3∗𝑉𝑚/𝐼𝑚
(𝑉𝑟/√3)/𝐼𝑟
Ω/phase
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Tap position
9
Rated power
16MVA
HV rated voltage:
220Kv
LV rated voltage
20Kv
HV rated current:
42A
LV rated current
419A
LV
HV
Vm
Im
Zo
Zo%
Vector Group Check Test
3.5.7) Purpose of test:
- Vector group testing is done to ensure the parallel operation of three
phase transformer connected in the power system. There are various
ways of connecting three phase transformers with phase shift of 0 ,±30
and 180 degree This phase shift is due to different ways for connecting
the primary and secondary windings of the transformer. To connect the
various transformer, the secondary waveform should be same for all the
transformer otherwise a large circulating current will flow in system that
may cause short circuit
3.5.8) Work Instructions/Test Procedures:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Thoroughly clean all Bushings of the Transformer to be tested
3- Keep the tap changer of transformer at Nominal Tap
4- Identify test parameters & terminals for proper Connection (Consider
a Transformer with HV Side R-Y-B-N and LV side r-y-b)
5- Refer to the following illustrations shown below for test connections:
Page | 116
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
6- Record the test result in the applicable test forms and evaluate all
measured values are satisfying the following table:
1T-2t = 1S-2t
1S-2t = 1S-2s
1T-2s > 1T-2t
1R-1N = (1R-2t) + (2t-1N)
Page | 117
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Magnetic Balance Test
3.5.9) Purpose of test:
- Magnetic Balance test used to find the distribution of Flux (Magnetic),
Core Assembly Condition and defect in winding (If any). It may check at
HV Side or LV Side as per requirement/ site condition.
3.5.10) Work Instructions/Test Procedures:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Thoroughly clean all Bushings of the Transformer to be tested
3- Keep the tap changer of transformer in normal position.
4- Refer to the following illustrations shown below for test connections:
- TEST CONNECTION FOR POWER TRANSFORMER MAGNETIC
BALANCE TEST WITH INJECTED VOLTAGE ACROSS R & N PHASES:
- TEST CONNECTION FOR POWER TRANSFORMER MAGNETIC
BALANCE TEST WITH INJECTED VOLTAGE ACROSS R & N PHASES:
Page | 118
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- TEST CONNECTION FOR POWER TRANSFORMER MAGNETIC
BALANCE TEST WITH INJECTED VOLTAGE ACROSS R & N PHASES:
5- Record the test result in the applicable test forms.
➢
Important Note: The Injected Voltage across R-N phases shall equal
to the sum of measured voltages between Y-N and B-N. The
Transformer will be deemed not in good condition if this criterion is
not met.
➢ Note: selected tap position:9 for our example or power transformer.
Voltage measured at HV side (V)
Voltage applied (V)
1R-1N
1R-1N
231
1S-1N
230.8
1T-IN
231
1S-1N
1T-1N
Voltage measured at LV side
Voltage applied (V)
rs
1R-1N
231
1S-1N
230.8
1T-IN
231
Page | 119
st
tr
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Short Circuit Impedance Test
3.5.11) Purpose of test:
- The main purpose of this test is to compute the following:
• Equivalent impedance of the transformer referred to primary and
secondary.
• Cu loss of the transformer at any desired load.
• Total voltage drops of the transformer referred to primary and
secondary.
3.5.12) Work Instructions/Test Procedures:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Thoroughly clean all Bushings of the Transformer to be tested
3- Identify test parameters and terminals for proper connections.
4- Conduct testing as per the following illustrated test Connections:
Page | 120
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
5- Record the Measured Input Voltage and Current as shown in the
Above Connections at each phase for the first Tap, middle tap and
last tap.
6- For each of the recorded Input and Current Voltage, Calculate the
Average Value from all the phases.
7- Record the Rated Current and Voltage at first, middle and last taps.
8- Calculate the Impedance Voltage and %Z from by using the
following formulas for each phase.
Impedance Voltage =
Z% =
Rated Tap Current x measured Voltage
Impedance Voltage
Rated Tap Voltage
Average Current
𝑥100
➢ Criteria: Acceptance Criteria: (As per SEC Standard) ±10%
Page | 121
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Excitation Current (No load) Test
3.5.13) Purpose of test:
- The purpose of this test is to detect short-circuited turns, poor electrical
connections, core de-laminations, core lamination shorts, tap changer
problems, and other possible core and winding problems. On threephase transformers, results are also compared between phases.
3.5.14) Work Instructions/Test Procedures:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Thoroughly clean all Bushings of the Transformer to be tested
3- Identify test parameters and terminals for proper connections.
4- Conduct testing as per the following illustrated test Connections:
Measure the No Load Current at First Tap, Middle tap, and Last tap.
Page | 122
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
5- Record the measured values of No-Load Current for HV and LV test
connections on applicable test forms/Formats
Test Mode
1R-1N
UST-A
1S-1N
UST-A
1T-IN
UST-A
I (mA)
➢ Criteria: Acceptance Criteria: As FAT results.
Page | 123
P (W)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SFRA Test
3.5.15) Purpose of test:
- SFRA test is nothing but a Sweep Frequency Response analysis, which
is used to find out the physical condition of transformer windings.
- The winding of transformer or alternator rotor’s may be exposed to
mechanical stresses during unsafe transportation, lightning impulse,
heavy short circuit faults, transient switching impulses, and DC
component etc. Due to these mechanical stresses may damage the
transformer’s winding or cause displacement or deformation of
transformer windings from its original position.
- If the mechanical stress is high or exceeded the threshold limit, then
the transformer winding may touch the core which creates the earth
fault between the winding to core.
➢ Main Purposes of SFRA Test:
- Transformer Core displacement
- Winding displacement for both rotor and transformer
- Broken or loosen clamp connections
- Inter turn short circuit
- Internal short circuit
- Winding to Core Earth fault
- Winding Open circuit condition
Page | 124
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.5.16) Work Instructions/Test Procedures:
1- Position the test equipment/s on a safe location where possibility of
falling objects is remote to happen.
2- Ensure proper grounding of the Transformer and Test equipment to
be used.
3- Refer to the following diagrams for proper test connections using
different FRA Measurement methods:
- Considering that the Transformer being tested is in YNd11 Group,
Perform the FRA test by using the End-to-End OPEN circuit method
as shown in the diagram on the left and repeat for each of the phases.
Page | 125
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Considering that the Transformer being tested is in YNd11 Group,
Perform the FRA test by using the CAPACITIVE inter-winding test
method as shown in the diagram on the left and repeat for each of the
phases.
Page | 126
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Considering that the Transformer being tested is in YNd11 Group,
Perform the FRA test by using the End-to-End SHORT circuit
method as shown in the diagram on the left and repeat for each of
the phases.
- Considering that the Transformer being tested is in YNd11 Group,
Perform the FRA test by using the INDUCTIVE inter-winding test
method as shown in the diagram on the left and repeat for each of
the phase.
Page | 127
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
4- Record the test results in standard test forms and evaluate as per the
below common methods of FRA measurement assessment:
• Time-based comparison: Current SFRA results are compared
to previous results on the same power transformer under test.
SFRA Results for all phases of HV Side
SFRA Results for all phases of LV Side
Page | 128
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Type-based comparison: Current SFRA results are compared
to another power transformer of the same design (sister unit).
• Phase-based comparison: Current SFRA results of one phase
are compared to the results of the other phases of the same
power transformer under test.
SFRA Result for Separate R-Phase of HV Side
SFRA Result for Separate R-Phase of LV Side
Page | 129
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SFRA Test Result for Power Transformer as example.
Page | 130
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Oil and Winding Temperature Calibration Test
3.5.17) Purpose of test:
- The temperature parameter represents the most important factor to
fulfill quality, operational safety, and reliability of industrial processes.
Thermocouples, RTDs and any other temperature sensors, when
installed in an industrial process, they are subjected to mechanical,
thermal, and chemical stresses which accelerate their aging. Therefore,
it is a recommended procedure to inspect, check and calibrate each
sensor during the commissioning phase and at regular and programmed
time intervals.
3.5.18) Work Instructions/Test Procedures:
1- Position the test equipment/s on a safe location where possibility of
falling objects is remote to happen.
2- Ensure proper grounding of the equipment to be used.
3- Set up of the Test Set:
• Temperature Indicator Sensor calibration by Immersion in a heated
Oil:
-
Actual photos of Oil Temperature
calibration test on site
Page | 131
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Record The temperature in the Oil Temp Indicator sensor and
evaluate the result as per the acceptance.
- Repeat the Procedure for HV and LV winding Temperature
Indicators.
➢ Criteria: AS per FAT results ≤ ± 3 degree.
• Winding Temperature Calibration by Secondary Current Injection:
4- Record the Following Temperature Measurements and evaluate as
per the Transformer’s Manual specifications:
• Oil temp at Start (A)
• Oil temp at end (B)
• Winding temp before current injection (C)
• Winding temp after 45mins (D)
• Reference simulated temperature Rise
• Simulated Temperature rise measured ((D-C) – (B-A))
➢ Note: Measured Temperatures must be as per manufacture manual
specs.
Reference Temp
No. of Temp. Ref
Page | 132
Oil Temp Indicator
HV Winding
Temp. Indicator1
HV Winding
Temp. Indicator2
Inspection Test Plan
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
On Load Tap Changer Test
3.5.19) Purpose of test:
- Transformers equipped with on-load tap changers (OLTCs) are crucial
components in the power system due to their purpose of maintaining
the voltage output desired. To maintain these voltages, they are
required to perform frequent operations.
- We make sure control operating panel of OLTC meet operation
requirements.
3.5.20) Work Instructions/Test Procedures:
1- Position the test equipment/s on a safe location where possibility of
falling objects is remote to happen.
2- Ensure proper grounding of the Transformer and Test equipment to
be used.
3- Measure the Motor Starting Current of the OLTC MDU for all
phases and repeat with 1 phase removed for a specific time duration
as per the below figure.
4- Measure the Motor Running Current of the OLTC MDU for all
phases and repeat with 1 phase removed for a specific time duration.
5- Measure the Voltages across R-Y, Y-B, and B-R phases during
Operation of the OLTC’s MDU.
Page | 133
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
6- Physically check the rotation of the OLTC MDU during operation
by verifying if the direction of rotation is in clockwise direction.
7- Measure the resistance of OLTC MDU of all taps and repeat for all
Modules
8- Record and Evaluate Test results in Test Forms.
Remarks
#
Description
(OK / NOT OK)
1
2
3
4
5
6
7
8
9
10
11
12
HEATER
Mechanical operation check
Socket outlet
MECHANICAL LOCK (LOWER & UPPER) LIMIT
ELECTRICAL LOCK (LOWER & UPPER) LIMIT
INTERLOCKING SWITCH WITH HAND CRANK
Electrical operation
COUNTER OPERATION checkup
Local operation switch
Local remote check
STOP AND ROTATION POINTERS
WIRING check
13
CHECK VOLTAGE, PHASE ROTATION and MOTOR FOR
OLTC running CURRENT (AMPS)
Page | 134
voltage
current
Phase
rotation
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Oil Dielectric Breakdown Test
3.5.21) Purpose of test:
- Oils that combine a high flashpoint with high dielectric strength have
long been used as an insulating medium in transformers, switchgear,
and other electrical apparatus. To ensure that the dielectric strength of
the oil does not deteriorate however, proper maintenance is essential,
and the basis of proper maintenance is testing.
- For in-service equipment, there are many test techniques for evaluating
the condition of the insulating oil. If the technique of dissolved gas
analysis is excluded, oil tests can be divided into two basic groups.
• The first group includes tests that are concerned with the
immediate condition and acceptability of the insulation in an item
of electrical equipment. This group includes dielectric breakdown
voltage testing as well as moisture measurement by the Karl
Fischer (KF) method, and determination of insulation condition
by measuring the dielectric dissipation factor.
• The second group includes tests that look at the degree of
degradation and aging of the equipment’s insulation system.
These tests include interfacial tension, acidity (neutralization
value), resistivity and visual determination of color and
appearance of the insulating oil.
3.5.22) Work Instructions/Test Procedures:
1- Position the test equipment on a safe location where possibility of
falling objects is remote to happen.
2- Ensure proper grounding of the equipment to be used.
3- Set up of the Test Set:
• Place the instrument on a firm, reasonably level base and dry
area.
• Clean the test cup/vessel using a dry hydrocarbon solvent, then
dry and fill with the sample fluid to a prescribed level.
• The liquid is then gently agitated to remove air bubbles, and then
allowed to stand for 3 to 5 minutes.
4- Connect the test cup/vessel to the oil dielectric tester and apply the
necessary voltage(kV/second) until the oil sample breaks down.
Page | 135
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
(When the current arcs across the gap between the electrodes, the
voltage at that instant is the dielectric breakdown strength).
➢ Typical oil color specimens the darker the color the more contaminants
present:
5- Record and evaluate the results in the Test Form/s.
Model
Power Transformer
S/N
Sample
1
2
3
4
5
6
mean
Page | 136
Upper OR Lower
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Supervision Equipment Functional Test
3.5.23) Purpose of test:
- To guide the responsible persons in conducting Supervision
Equipment’s MK Scheme & Functional Check of Power Transformer.
3.5.24) Work Instructions/Test Procedures:
1- Ensure proper grounding of the Transformer and Test equipment to
be used.
2- Check all circuits as per schematic drawing of MK panel and
highlight with yellow if its ok.
3- Alarms & trips shall be checked in HMI’s, workstations, and
gateways. Trip commands shall be checked by closing related CB’s.
4- All functions shall be checked as per scheme, checklist, test forms
and settings and all should be recorded in checklist and test forms
which are to be duly signed.
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Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Item
Equipment
1
OTI1
Oil temperature Indicator
2
OTI2
Oil temperature Indicator
3
WTI1
Winding Temperature Indicator
4
OTL1
Oil Level Indicator for Main tank
Signal
Air cooling control
Air cooling control
Alarm
Trip
Air cooling control
Air cooling control
Alarm
Trip
spare
spare
Alarm
Trip
Low oil level alarm
High oil level alarm
Low oil level alarm
High oil level alarm
5
OTL/TC1
Oil Level Indicator for OLTC
6
GOR1
Buchholz Relay for Main Tank
7
GOR/TC1
Buchholz Relay for OLTC
PRD1
Pressure Relief Device for Main Tank
PRD2
Pressure Relief Device for Main Tank
PRD1
Quick acting oil pressure relay
8
9
10
Page | 138
Low oil level alarm
Low oil level alarm
High oil level alarm
High oil level alarm
Alarm
Alarm
Trip
Trip
Trip 1
Trip 2
Trip
Trip
Trip
Trip
TRIP
Terminal at
Marshalling
Status
Inspection Test Plan
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Traction Transformers
Procedure Tests
Page | 139
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Transformer Technical Data (Name Plate)
- For example: this name plate for Traction transformer installed at Traction_1 SS
-
Page | 140
Inspection Test Plan
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers by consultant.
S.N
Type
Make
1
Megger 5K VDC
Megger
2
CPC 100
OMICRON
3
Diesel Generator
PREDATOR
4
Multimeter + Clamp meter
Megger
5
CP TD 12/15
OMICRON
6
FRAX99 – Sweep Frequency Response
Analysis
7
Microcal T500
8
ZWJD111
Megger
Euro Tron
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 141
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that transformer is ready to test and doesn’t have a damage
part which prevents perfuming tests.
#
TEST DESCRIPTION
REMARKS
(OK / NOT OK)
Inspect for physical damage/defects (see for any cracks, chips, etc. on
55. visible outer layer of the cast resin).
56. Check nameplate for correctness.
1.
Check tightness of all bolted connections (torque wrench method).
2.
Check that all grounding is securely connected, including star point
neutral.
3.
Perform all specific checks per manufacturer instructions
4.
Check proper operation of all auxiliary devices (if applicable)
Polarization Index Test:
3.2.1) Purpose of test:
- Check quality of winding insulation resistance before performing high
pot test and comparing it by name plate values or FAT results if its
accepted.
- Check for all connections as shown below.
➢ Applied Voltage: 2500/5000V DC
➢ Criteria: PI > 1.25
POLARIZATION INDEX (PI) =
10 min Insulation resistance (Meg−ohm) reading
1 min Insulation resistance (Meg−ohm) reading
≥ 1.25.
3.2.2) Work Instructions/Test Procedures:
1- Connect megger tester as shown below.
2- Apply voltage test value for each connection.
3- Evaluate test results and compare it by FAT results.
4- Calculate PI value for each connection and make sure that more than
criteria value.
Page | 142
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1)HV-LV winding insulation
resistance test
4)Core-Frame insulation
resistance test
Winding Under
Test
HV –E
HV – LV1
HV-LV2
LV1-E
LV2-E
LV1-LV2
Core-E
Clamp-E
Page | 143
Test
Voltage
2)HV winding-Ground insulation
resistance test
3)LV winding-Ground
insulation resistance test
5)Frame-Earth insulation
resistance test
6)Core-Earth insulation
resistance test
15
Seconds
(G Ω)
60
Seconds
(G Ω)
600
Seconds
(G Ω)
PI
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Turns-Ratio (TTR) Test:
3.3.1) Purpose of test:
- Ratio test is used to make sure that the ratio between the windings of the
primary and secondary coils follow the proper specifications.
- This test ensures that the transformer will provide the proper step down
in voltage.
➢ The CPC 100 tester is used or any approved suitable tester, the turns-ratio
test can be performed by two types of connections (1-PH or 3-PH)
connections which are available at site and approved, we use 1st
connection.
➢ Criteria: The acceptance criteria for field tests that the range of
measured ratio shall be equal to the calculated ratio ±0.5 %.
3) Single-Phase Test Connection: CPC 100 only with a maximum output
voltage of 2000V.
4) Three-Phase Test Connection: CPC 100 + CP SB1 with a maximum
output voltage of 300V.
3.3.2) Work Instructions/Test Procedures :
1- Connect CPC100 connections as shown below.
2- Apply selected test type from CPC100 window.
3- Connect primary winding connections and be careful during test.
4- Evaluate results during each tap.
Page | 144
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Tap Voltage
Tap
H.V
LV
Cal.
Ratio
Measured Value
VRS/Vrn 1 Error% mA VTS/Vtn 2 Error% mA
No. of Taps 220Kv 27.5Kv
DC Winding Resistance Test:
3.4.1) Purpose of test:
- The purpose of measuring the DC winding resistance of the transformer
windings is to check the welding quality of the winding joints and whether
the windings have short circuits between the windings, whether the contact
positions of the voltage tap switches are good and whether the actual
positions of the taps match, whether there is a break in the lead wires or not.
➢ The CPC 100 is required or any approved tester. Before beginning the DC
Winding Resistance test, please consider the following,
➢ The DC Winding Resistance Test should always be the last test performed
on a power transformer.
➢ The DC Winding Resistance test can be performed with the CPC 100 or
another approved tester using three methods, which include:
• 400A DC Method – Recommend for measuring resistances < 50mΩ and
(e.g. typically useful for performing a low-voltage winding resistance
measurement)
• 6A DC Method – Recommended for measuring resistances > 50mΩ and
<10Ω (e.g. typically useful for performing a high-voltage winding
resistance measurement).
• 2-Wire Method – Recommended for measuring resistances >10Ω only.
➢ Note: make sure that each phase results must same as other phases within %error.
Page | 145
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.4.2) Work Instructions/Test Procedures :
1- Connect CPC100 connections as shown below.
2- Apply selected test type from CPC100 window.
3- Connect primary winding connections and be careful during test.
4- Repeat this step for all phases at all number of taps.
5- Evaluate results during each tap.
- High Voltage Side Winding Resistance:
➢ Criteria: As per FAT Results.
➢ Ambient Temperature: 28ᵒC
RS (Ω)
TAP #
TS (Ω)
No. of taps
- Low Voltage Winding Resistance:
➢ Criteria: As per FAT Results.
➢ Ambient Temperature: 28ᵒC
rn 1 (mΩ)
Page | 146
tn 1 (mΩ)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Loss factor tan δ and capacitance C of the winding Test:
3.5.1) Purpose of test:
- The main purpose of the tan delta test is to make sure of maintaining a
secure and reliable functioning of the transformer. With the calculation
of dissipation factor and capacitance values, it provides the result of
insulation behavior of bushings and in windings too.
- Variation in the capacitance value, for instance, it indicates partial kind
of breakdowns in bushings and automated movement of windings.
Insulation deprivation, aging of the equipment, enhancement in the
energy levels is transformed into heat. The number of losses in these is
calculated as the dissipation factor.
- With the tan delta testing method, one can easily know the dissipation
factor and the capacitance values at the required level of frequencies.
So, any kind of aging factor can be identified earlier, and the
corresponding action can be implemented.
➢ Criteria: The acceptance criteria for field tests that the measured value
doesn’t exceed 0.5% according to FAT.
3.5.2) Work Instructions/Test Procedures:
1- A Tan Delta test is performed by applying an ac voltage to a test cell
of known gap, measuring the total current flow through the oil, and
separating and comparing the reactive and resistance portions of the
current passing through the oil.
2- Connect CPC100 by CP TD 12/15 Unit as shown below.
3- Short Circuit each winding of the transformer at its bushing terminals and
connect all windings to ground except the winding to be measured.
4- Apply 10kV Test voltage from CPC100 kit screen.
5- Apply all test for all connections are mentioned in table below.
Page | 147
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 148
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Insulation type
Test Mode
Test Voltage KV
HV / LV+G
GST
10
HV+ LV1/LV2+G
GST
10
HV+ LV2/LV1+G
GST
10
LV1/HV+LV2+G
GST
10
LV2/HV+LV1+G
GST
10
LV1+LV2/HV+G
GST
10
HV+LV1,2/G
GST
10
HV/LV1
USTA
10
HV/LV2
USTA
10
Page | 149
Capacitance nf
Tan Delta %
At 20 0C
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
loss factor tan δ and capacitance C of the Bushing Test
3.5.3) Purpose of test:
- The main purpose of the tan delta test is to make sure of maintaining a
secure and reliable functioning of the transformer. With the calculation
of dissipation factor and capacitance values, it provides the result of
insulation behavior of bushings and in windings too.
- Variation in the capacitance value, for instance, it indicates partial kind
of breakdowns in bushings and automated movement of windings.
Insulation deprivation, aging of the equipment, enhancement in the
energy levels is transformed into heat. The number of losses in these is
calculated as the dissipation factor.
- All modern bushings rated 23 kV and higher have a power factor, or
capacitance tap which permits dissipation factor testing of the bushing
while it is in place on the apparatus without disconnecting any leads to
the bushing. The dis-septation factor is measured by the ungrounded
specimen test (UST) which eliminates the influence of transformer
winding insulation, breaker arc-interrupters, or support structures
which are connected to the bushing terminal.
➢ Criteria: The acceptance criteria for field tests that the measured value
doesn’t exceed 0.5% according to FAT.
3.5.4) Work Instructions/Test Procedures:
1- Connect CPC100 by CP TD 12/15 Unit as shown below.
2- Apply 10kV Test voltage from CPC100 kit screen.
3- Connect test ground to apparatus ground.
4- Connect the high-voltage lead to the terminal at the top of the
bushing and the low-voltage lead (red) to the power factor tap.
5- Ground the apparatus tank. The tap is normally grounded through a
spring, and it is necessary,
6- when making measurements, to remove the plug which seals and
grounds the tap. Use the UST measure red, ground blue test mode
setting (UST-R).
7- Apply all test for all phases are mentioned in table below.
8- Evaluate results and check if it accepted.
Page | 150
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Connection of UST
mode for Bushing
insulation test.
- This kit connection for
illustration only.
Test Voltage
(kV)
Insulation type
R
Test Mode
10
S
10
T
10
Page | 151
HV
Tan Delta %
Capacitance (pF)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Vector Group Check Test
3.5.5) Purpose of test:
- Vector group testing is done to ensure the parallel operation of three
phase transformer connected in the power system. There are various
ways of connecting three phase transformers with phase shift of 0 ,±30
and 180 degree This phase shift is due to different ways for connecting
the primary and secondary windings of the transformer. To connect the
various transformer, the secondary waveform should be same for all the
transformer otherwise a large circulating current will flow in system that
may cause short circuit
3.5.6) Work Instructions/Test Procedures:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Thoroughly clean all Bushings of the Transformer to be tested
3- Keep the tap changer of transformer at Nominal Tap
4- Identify test parameters & terminals for proper Connection (Consider
a Transformer with HV Side R-S-T and LV side rn1&tn2)
5- Refer to the following illustrations shown below for test connections:
Page | 152
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
6- Record the test result in the applicable test forms and evaluate all
measured values are satisfying the following table:
R-S=T-S=S-T
R-S>S-n1
T-S>S-n2
R-S=(r-n1) +(S-n1)
T-S=(t-n2) +(S-n2)
Page | 153
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Magnetic Balance Test
3.5.7) Purpose of test:
- Magnetic Balance test used to find the distribution of Flux (Magnetic),
Core Assembly Condition and defect in winding (If any). It may check at
HV Side or LV Side as per requirement/ site condition.
3.5.8) Work Instructions/Test Procedures:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Thoroughly clean all Bushings of the Transformer to be tested
3- Keep the tap changer of transformer in normal position.
4- Refer to the following illustrations shown below for test connections:
- TEST CONNECTION FOR POWER TRANSFORMER MAGNETIC
BALANCE TEST WITH INJECTED VOLTAGE ACROSS R & N PHASES:
- TEST CONNECTION FOR POWER TRANSFORMER MAGNETIC
BALANCE TEST WITH INJECTED VOLTAGE ACROSS R & N PHASES:
- TEST CONNECTION FOR POWER TRANSFORMER MAGNETIC
BALANCE TEST WITH INJECTED VOLTAGE ACROSS R & N PHASES:
Page | 154
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
5- Record the test result in the applicable test forms.
➢
Important Note: The Injected Voltage across R-N phases shall equal to the
sum of measured voltages between Y-N and B-N. The Transformer will be
deemed not in good condition if this criterion is not met.
➢ Note: selected tap position:9b for our example or power transformer.
Voltage measured at HV side (V)
Voltage applied (V)
RT
R-T
RS
ST
394
Voltage measured at LV side (V)
Voltage applied (V)
n1-n2
R-T
r-n1
t-n2
t-r
394
Condition n1&n2
Voltage applied (V)
r-n1
R-T
Page | 155
394
t-n2
t-r
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Short Circuit Impedance Test
3.5.9) Purpose of test:
- The main purpose of this test is to compute the following:
• Equivalent impedance of the transformer referred to primary and
secondary.
• Cu loss of the transformer at any desired load.
• Total voltage drops of the transformer referred to primary and
secondary.
3.5.10) Work Instructions/Test Procedures:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Thoroughly clean all Bushings of the Transformer to be tested
3- Identify test parameters and terminals for proper connections.
4- Conduct testing as per the following illustrated test Connections:
5- Record the Measured Input Voltage and Current as shown in the
Above Connections at each phase for the first Tap, middle tap and
last tap.
6- For each of the recorded Input and Current Voltage, Calculate the
Average Value from all the phases.
Page | 156
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
7- Record the Rated Current and Voltage at first, middle and last taps.
8- Calculate the Impedance Voltage and %Z from by using the
following formulas for each phase.
Impedance Voltage =
Z% =
Rated Tap Current x measured Voltage
Impedance Voltage
Rated Tap Voltage
Average Current
𝑥100
➢ Criteria: Acceptance Criteria: (As per SEC Standard) ±10%
Tap
1
Voltage applied in volts
Current measured in Amp
Z%
Error %
RS
427
2.3
12.86
1.47
9
RS
424
2.8
12.51
0.6
17
RS
422.8
3.5
12.32
0.52
1
ST
422.6
2.2
13.12
1.9
9
ST
422.7
2.8
12.47
1.35
17
ST
423.1
3.5
12.33
0.93
Page | 157
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Excitation Current (No load) Test
3.5.11) Purpose of test:
- The purpose of this test is to detect short-circuited turns, poor electrical
connections, core de-laminations, core lamination shorts, tap changer
problems, and other possible core and winding problems. On threephase transformers, results are also compared between phases.
3.5.12) Work Instructions/Test Procedures:
6- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
7- Thoroughly clean all Bushings of the Transformer to be tested
8- Identify test parameters and terminals for proper connections.
9- Conduct testing as per the following illustrated test Connections:
Measure the No Load Current at First Tap, Middle tap, and Last tap.
Page | 158
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
10- Record the measured values of No-Load Current for HV and LV test
connections on applicable test forms/Formats
Excitation Current TEST
I mA
P (W)
T-S
Test mode UST-A
22.39
114.79
R-S
Test mode UST-A
22.59
116.61
➢ Criteria: Acceptance Criteria: As FAT results.
Page | 159
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SFRA Test
3.5.13) Purpose of test:
- SFRA test is nothing but a Sweep Frequency Response analysis, which is
used to find out the physical condition of transformer windings.
- The winding of transformer or alternator rotor’s may be exposed to
mechanical stresses during unsafe transportation, lightning impulse, heavy
short circuit faults, transient switching impulses, and DC component etc.
Due to these mechanical stresses may damage the transformer’s winding
or cause displacement or deformation of transformer windings from its
original position.
- If the mechanical stress is high or exceeded the threshold limit, then the
transformer winding may touch the core which creates the earth fault
between the winding to core.
➢ Main Purposes of SFRA Test:
- Transformer Core displacement
- Winding displacement for both rotor and transformer
- Broken or loosen clamp connections
- Inter turn short circuit
- Internal short circuit
- Winding to Core Earth fault
- Winding Open circuit condition
-
Page | 160
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.5.14) Work Instructions/Test Procedures:
1- Position the test equipment/s on a safe location where possibility of
falling objects is remote to happen.
2- Ensure proper grounding of the Transformer and Test equipment to
be used.
3- Refer to the following diagrams for proper test connections using
different FRA Measurement methods:
- Considering that the Transformer being tested is in YNd11 Group,
Perform the FRA test by using the End-to-End OPEN circuit method
as shown in the diagram on the left and repeat for each of the phases.
Page | 161
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Considering that the Transformer being tested is in YNd11 Group,
Perform the FRA test by using the CAPACITIVE inter-winding test
method as shown in the diagram on the left and repeat for each of the
phases.
Page | 162
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Considering that the Transformer being tested is in YNd11 Group,
Perform the FRA test by using the End-to-End SHORT circuit
method as shown in the diagram on the left and repeat for each of
the phases.
- Considering that the Transformer being tested is in YNd11 Group,
Perform the FRA test by using the INDUCTIVE inter-winding test
method as shown in the diagram on the left and repeat for each of
the phase.
Page | 163
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
4- Record the test results in standard test forms and evaluate as per the
below common methods of FRA measurement assessment:
• Time-based comparison: Current SFRA results are compared
to previous results on the same power transformer under test.
• Type-based comparison: Current SFRA results are compared
to another power transformer of the same design (sister unit).
• Phase-based comparison: Current SFRA results of one phase
are compared to the results of the other phases of the same
power transformer under test.
SFRA Result for Separate R-Phase of HV Side
SFRA Result for Separate r-Phase of LV Side
Page | 164
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SFRA Test Results
Report date: 2022-11-19
Date of Test:
12-044-22
Time of Test:
08:06:46
Company Name:
AVEC
Location:
LRT1
Test Object:
212015N
Manufacturer:
Yunnan
Serial Number:
212015N
Built Year:
2021
Phase Design:
3
Winding Configuration:
Vv0/Vv6
KV Rating:
220-27.5-
KVA Rating:
40-40-
NLTC Position:
LTC Position:
1
Temperature:
Reason For Test:
Tested By:
Notes:
SFRA Test Result for Traction Transformer as example.
Page | 165
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Oil and Winding Temperature Calibration Test
3.5.15) Purpose of test:
- The temperature parameter represents the most important factor to
fulfill quality, operational safety, and reliability of industrial processes.
Thermocouples, RTDs and any other temperature sensors, when
installed in an industrial process, they are subjected to mechanical,
thermal, and chemical stresses which accelerate their aging. Therefore,
it is a recommended procedure to inspect, check and calibrate each
sensor during the commissioning phase and at regular and programmed
time intervals.
3.5.16) Work Instructions/Test Procedures:
5- Position the test equipment/s on a safe location where possibility of
falling objects is remote to happen.
6- Ensure proper grounding of the equipment to be used.
7- Set up of the Test Set:
• Temperature Indicator Sensor calibration by Immersion in a heated
Oil:
Page | 166
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Record The temperature in the Oil Temp Indicator sensor and
evaluate the result as per the acceptance.
- Repeat the Procedure for HV and LV winding Temperature
Indicators.
➢ Criteria: AS per FAT results ≤ ± 3 degree.
• Winding Temperature Calibration by Secondary Current Injection:
8- Record the Following Temperature Measurements and evaluate as
per the Transformer’s Manual specifications:
• Oil temp at Start (A)
• Oil temp at end (B)
• Winding temp before current injection (C)
• Winding temp after 45mins (D)
• Reference simulated temperature Rise
• Simulated Temperature rise measured ((D-C) – (B-A))
➢ Note: Measured Temperatures must be as per manufacture manual
specs.
Reference Temp
No. of Temp. Ref
Page | 167
Oil Temp Indicator
HV Winding
Temp. Indicator1
HV Winding
Temp. Indicator2
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
On Load Tap Changer Test
3.5.17) Purpose of test:
- Transformers equipped with on-load tap changers (OLTCs) are crucial
components in the power system due to their purpose of maintaining the
voltage output desired. To maintain these voltages, they are required to
perform frequent operations.
- We make sure control operating panel of OLTC meet operation
requirements.
3.5.18) Work Instructions/Test Procedures:
1- Position the test equipment/s on a safe location where possibility of
falling objects is remote to happen.
2- Ensure proper grounding of the Transformer and Test equipment to
be used.
3- Measure the Motor Starting Current of the OLTC MDU for all
phases and repeat with 1 phase removed for a specific time duration
as per the below figure.
4- Measure the Motor Running Current of the OLTC MDU for all
phases and repeat with 1 phase removed for a specific time duration.
5- Measure the Voltages across R-Y, Y-B, and B-R phases during
Operation of the OLTC’s MDU.
Page | 168
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
6- Physically check the rotation of the OLTC MDU during operation
by verifying if the direction of rotation is in clockwise direction.
7- Measure the resistance of OLTC MDU of all taps and repeat for all
Modules
8- Record and Evaluate Test results in Test Forms.
Remarks
#
Description
(OK / NOT OK)
1
2
3
4
5
6
7
8
9
10
11
12
HEATER
Mechanical operation check
Socket outlet
MECHANICAL LOCK (LOWER & UPPER) LIMIT
ELECTRICAL LOCK (LOWER & UPPER) LIMIT
INTERLOCKING SWITCH WITH HAND CRANK
Electrical operation
COUNTER OPERATION checkup
Local operation switch
Local remote check
STOP AND ROTATION POINTERS
WIRING check
13
CHECK VOLTAGE, PHASE ROTATION and MOTOR FOR
OLTC running CURRENT (AMPS)
Page | 169
voltage
current
Phase
rotation
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Oil Dielectric Breakdown Test
3.5.19) Purpose of test:
- Oils that combine a high flashpoint with high dielectric strength have
long been used as an insulating medium in transformers, switchgear,
and other electrical apparatus. To ensure that the dielectric strength of
the oil does not deteriorate however, proper maintenance is essential,
and the basis of proper maintenance is testing.
- For in-service equipment, there are many test techniques for evaluating
the condition of the insulating oil. If the technique of dissolved gas
analysis is excluded, oil tests can be divided into two basic groups.
• The first group includes tests that are concerned with the
immediate condition and acceptability of the insulation in an item
of electrical equipment. This group includes dielectric breakdown
voltage testing as well as moisture measurement by the Karl
Fischer (KF) method, and determination of insulation condition
by measuring the dielectric dissipation factor.
• The second group includes tests that look at the degree of
degradation and aging of the equipment’s insulation system.
These tests include interfacial tension, acidity (neutralization
value), resistivity and visual determination of color and
appearance of the insulating oil.
3.5.20) Work Instructions/Test Procedures:
1- Position the test equipment on a safe location where possibility of
falling objects is remote to happen.
2- Ensure proper grounding of the equipment to be used.
3- Set up of the Test Set:
• Place the instrument on a firm, reasonably level base and dry
area.
• Clean the test cup/vessel using a dry hydrocarbon solvent, then
dry and fill with the sample fluid to a prescribed level.
• The liquid is then gently agitated to remove air bubbles, and then
allowed to stand for 3 to 5 minutes.
4- Connect the test cup/vessel to the oil dielectric tester and apply the
necessary voltage(kV/second) until the oil sample breaks down.
Page | 170
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
(When the current arcs across the gap between the electrodes, the voltage at that
instant is the dielectric breakdown strength).
➢ Typical oil color specimens the darker the color the more contaminants
present:
5- Record and evaluate the results in the Test Form/s.
Model
Traction Transformer
S/N
212015N
1
2
3
4
5
6
mean
Page | 171
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Supervision Equipment Functional Test
3.5.21) Purpose of test:
- To guide the responsible persons in conducting Supervision
Equipment’s MK Scheme & Functional Check of Power Transformer.
3.5.22) Work Instructions/Test Procedures:
1- Ensure proper grounding of the Transformer and Test equipment to
be used.
2- Check all circuits as per schematic drawing of MK panel and
highlight with yellow if its ok.
3- Alarms & trips shall be checked in HMI’s, workstations, and
gateways. Trip commands shall be checked by closing related CB’s.
4- All functions shall be checked as per scheme, checklist, test forms
and settings and all should be recorded in checklist and test forms
which are to be duly signed.
Page | 172
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Item
Equipment
1
OTI1
Oil temperature Indicator
2
OTI2
Oil temperature Indicator
3
WTI1
Winding Temperature Indicator
4
OTL1
Oil Level Indicator for Main tank
Signal
Air cooling control
Air cooling control
Alarm
Trip
Air cooling control
Air cooling control
Alarm
Trip
spare
spare
Alarm
Trip
Low oil level alarm
High oil level alarm
Low oil level alarm
High oil level alarm
5
OTL/TC1
Oil Level Indicator for OLTC
6
GOR1
Buchholz Relay for Main Tank
7
GOR/TC1
Buchholz Relay for OLTC
PRD1
Pressure Relief Device for Main Tank
PRD2
Pressure Relief Device for Main Tank
PRD1
Quick acting oil pressure relay
8
9
10
Page | 173
Low oil level alarm
Low oil level alarm
High oil level alarm
High oil level alarm
Alarm
Alarm
Trip
Trip
Trip 1
Trip 2
Trip
Trip
Trip
Trip
TRIP
Terminal at
Marshalling
Status
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Auxiliary Transformer
Procedure Tests
Page | 174
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Transformer Technical Data (Name Plate)
Manufacturer
Type
Rated Power
Serial Number
Vector Group
Rated Frequency
Short Circuit Impedance
Insulation Grade
Method of Cooling
No-Load Current
Tapping
Position
High Voltage
Voltage (V)
Current (A)
Low Voltage
Voltage (V)
Current (A)
No. of
taps
2) Test Equipment’s Used:
Note: Used tester types below or approved testers by consultant.
S.N
Type
Make
1
Megger 5K VDC
Megger
2
CPC 100
OMICRON
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 175
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that transformer is ready to test and doesn’t have a damage
parts which prevents perfuming tests.
#
TEST DESCRIPTION
REMARKS
(OK / NOT OK)
Inspect for physical damage/defects (see for any cracks, chips, etc. on
57. visible outer layer of the cast resin).
58. Check nameplate for correctness.
59. Check tightness of all bolted connections (torque wrench method).
Check that all grounding is securely connected, including star point
60. neutral.
61. Perform all specific checks per manufacturer instructions
62. Check proper operation of all auxiliary devices (if applicable)
Polarization Index Test:
3.2.1) Purpose of test:
- To determine the equipment in proper condition to put in service. Results
can be kept as record to compare in future and to understand the trend of
insulation during maintenance.
➢ Applied Voltage: 5000V DC
➢ Criteria: PI > 1.25
POLARIZATION INDEX (PI) =
10 min Insulation resistance (Meg−ohm) reading
1 min Insulation resistance (Meg−ohm) reading
≥ 1.25.
3.2.2) Work Instructions/Test Procedures:
1- Connect megger tester as shown below.
2- Apply voltage test value for each connection.
3- Evaluate test results and compare it by FAT results.
4- Calculate PI value for each connection and make sure that more than
criteria value.
Page | 176
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1)HV-LV winding insulation
resistance test
Test
Results
After 1 min
2)HV winding-Ground insulation
resistance test
Results
After 10 min
3)LV winding-Ground
insulation resistance test
PI
Remarks
(OK / NOT OK)
HV – LV
HV – Earth
LV – Earth
Turns-Ratio (TTR) Test:
3.3.1) Purpose of test:
- Main purpose of turn ratio test to check for actual turns ratio which in
the range of acceptable error.
➢ The CPC 100 tester is used or any approved suitable tester, the turns-ratio test
can be performed by two types of connections (1-PH or 3-PH) connections
which are available at site and approved, we use 1st connection.
➢ Criteria: Error ≤ 0.5
1) Single-Phase Test Connection: CPC 100 only with a maximum output
voltage of 2000V.
2) Three-Phase Test Connection: CPC 100 + CP SB1 with a maximum
output voltage of 300V.
Page | 177
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.3.2) Work Instructions/Test Procedures:
1- Connect CPC100 connections as shown below.
2- Apply selected test type from CPC100 window.
3- Connect primary winding connections and be careful during test.
4- Evaluate results during each tap.
Tap
Phases
No.
UV
of
UW
taps
VW
Rated Ratio
Measured Ratio
%
Error
Remarks
(OK / NOT OK)
DC Winding Resistance Test:
3.4.1) Purpose of test:
- Main purpose of winding resistance test to check for gross differences
between windings and for opens in the connections and readings are
compared with FAT results if they are acceptable.
➢ The CPC 100 is required or any approved tester. Before beginning the
DC Winding Resistance test, please consider the following,
➢ The DC Winding Resistance Test should always be the last test
performed on a power transformer.
➢ The DC Winding Resistance test can be performed with the CPC 100 or
another approved tester using three methods, which include:
Page | 178
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
•
400A DC Method – Recommend for measuring resistances < 50mΩ and
(e.g. typically useful for performing a low-voltage winding resistance
measurement)
• 6A DC Method – Recommended for measuring resistances > 50mΩ and
<10Ω (e.g. typically useful for performing a high-voltage winding
resistance measurement).
• 2-Wire Method – Recommended for measuring resistances >10Ω only.
➢ Note: make sure that each phase results must same as other phases within error.
3.4.2) Work Instructions/Test Procedures:
1- Connect CPC100 connections as shown below.
2- Apply selected test type from CPC100 window.
3- Connect primary winding connections and be careful during test.
4- Evaluate results during each tap.
Example of the single-phase test connection for Phase-A on the low voltage winding of a Dyn1
transformer.
Page | 179
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- High Voltage Side Winding Resistance:
➢ Criteria: As per FAT Results.
➢ Ambient Temperature: 28ᵒC
U V
Tap
Position
Result
(Ω)
Rc @
75 C
(Ω)
V W
FAT R
@ 30 C
(Ω)
Result
(Ω)
Rc @
75 C
(Ω)
W U
FAT R
@ 30 C
(Ω)
Result
(Ω)
Rc @
75 C
(Ω)
FAT R
@ 30 C
(Ω)
No. of
taps
- Low Voltage Winding Resistance:
➢ Criteria: As per FAT Results.
➢ Ambient Temperature: 28ᵒC
u v
Tap
Position
Rm
(mΩ)
Rc @
75 C
(mΩ)
v w
FAT R
@ 30 C
(mΩ)
Rm
(mΩ)
Rc @
75 C
(mΩ)
w u
FAT R
@ 30 C
(mΩ)
Rm
(mΩ)
1
Notes: this formula is used to calculate winding resistance referred to 75  C.
Rc: Calculated value at 75  C.
Rm: Measurement value which contained a measurement cable.
Ta: Ambient Temperature.
Rc = Rm*(235+75)
(236+Ta)
Page | 180
Rc @
75 C
(mΩ)
FAT R
@ 30 C
(mΩ)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Grounding Transformer
Procedure Tests
Page | 181
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Transformer Technical Data (Name Plate)
Manufacturer
Type
Rated Power
Serial Number
Vector Group
Rated Frequency
Rated Voltage
Rated Current
Method of Cooling
Zero Sequence Imp.
High Voltage
Tapping
Position
Voltage (V)
1-n
2) Test Equipment’s Used:
Note: Used tester types below or approved testers by consultant.
S.N
Type
Make
1
Megger 5K VDC
Megger
2
CPC 100
OMICRON
3
Multimeter
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 182
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that transformer is ready to test and doesn’t have a damage
parts which prevents perfuming tests.
#
TEST DESCRIPTION
1.
Inspect for physical damage/defects (see for any cracks ,chips ,etc. on
visible outer layer of the cast resin).
2.
Check nameplate for correctness.
3.
Check tightness of all bolted connections (torque wrench method).
4.
Check that all grounding is securely connected, including star point
neutral.
5.
Perform all specific checks per manufacturer instructions
6.
Check proper operation of all auxiliary devices (if applicable)
REMARKS
(OK / NOT OK)
Polarization Index Test:
3.2.1) Purpose of test:
- To determine the equipment in proper condition to put in service.
Results can be kept as record to compare in future and to understand the
trend of insulation during maintenance. Check quality of insulation
resistance between cire and ground.
➢ Applied Voltage: 5000V DC
➢ Criteria: PI > 1.25
POLARIZATION INDEX (PI) =
10 min Insulation resistance (Meg−ohm) reading
1 min Insulation resistance (Meg−ohm) reading
≥ 1.25.
3.2.2) Work Instructions/Test Procedures:
1- Connect megger tester as shown below.
2- Apply voltage test value for each connection.
3- Evaluate test results and compare it by FAT results.
4- Calculate PI value for each connection and make sure that more than
criteria value.
Page | 183
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2)Core-Ground insulation
resistance test
1)HV winding-Ground
insulation resistance test
Test
HV – Ground
Core – Ground
Page | 184
Results
After 15 sec
Results
After 1 min
PI
Remarks
(OK / NOT OK)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
DC Winding Resistance Test:
3.3.1) Purpose of test:
- Main purpose of winding resistance test to check for gross differences
between windings and for opens in the connections and readings are
compared with FAT results if they are acceptable.
➢ The CPC 100 is required or any approved tester. Before beginning the
DC Winding Resistance test, please consider the following,
➢ The DC Winding Resistance Test should always be the last test
performed on a power transformer.
➢ The DC Winding Resistance test can be performed with the CPC 100 or
another approved tester using three methods, which include:
• 400A DC Method – Recommend for measuring resistances < 50mΩ
and (e.g. typically useful for performing a low-voltage winding
resistance measurement)
• 6A DC Method – Recommended for measuring resistances > 50mΩ and
<10Ω (e.g. typically useful for performing a high-voltage winding
resistance measurement).
• 2-Wire Method – Recommended for measuring resistances >10Ω only.
➢ Note: make sure that each phase results must same as other phases within error.
3.3.2) Work Instructions/Test Procedures:
1- Connect CPC100 connections as shown below.
2- Apply selected test type from CPC100 window.
3- Connect primary winding connections and be careful during test.
4- Evaluate results during each tap.
Page | 185
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- High Voltage Side Winding Resistance:
➢ Criteria: As per FAT Results.
➢ Ambient Temperature: 35ᵒC
Tap
Position
A O
Result
(Ω)
FAT Result
(Ω)
B O
Result
(Ω)
FAT Result
(Ω)
C O
Result
(Ω)
FAT Result
(Ω)
1-n
Zero Sequence Impedance Test:
3.4.1) Purpose of test:
- Make sure zero sequence impedance value is within value of name
plate value or FAT results.
- The purpose of this test is to measure the zero-sequence impedance for all-star
connected windings of the transformer needed for earth fault protection and
earth fault current calculations.
➢ Criteria: it must be the same as manufacturer’s nameplate.
3.4.2) Work Instructions/Test Procedures:
1- Setup the CALIBRATED test instrument in a firm, reasonably level
base and dry area.
2- Thoroughly clean all Bushings of the Transformer to be tested.
3- Identify test parameters and terminals for proper connections.
4- Conduct testing as per the following illustrated test Connections:
• Test Connection with HV Winding Shorted.
Page | 186
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Record the Measured Current (Im) and Measured Voltage (Vm) at
first, middle and last tap.
• Calculate the Zero Sequence Impedance Percentage error by using
the formula:
3∗𝑉𝑚/𝐼𝑚
Z% =
Result
Z%
(𝑉𝑟/√3)/𝐼𝑟
Zero Sequence
Impedance %
Remarks
(OK / NOT OK)
Neutral Resistor Test:
3.5.1) Purpose of test:
- Calculate neutral resistance value which its value is very important for
earth fault protection setting, so we compare between measured value
and name plate value and make sure measured value is accepted.
➢ Criteria:
- it must be the same as manufacturer’s nameplate.
- As per FAT Results (20Ω±5%)
3.5.2) Work Instructions/Test Procedures:
1- Measure resistance connected to zigzag transformer by using
multimeter.
2- Evaluate results with name plate data.
Test Result
(Ω)
Remarks
(OK / NOT OK)
Neutral Current Transformer Test:
- This test is performed according to the CT Test procedures page:68.
Page | 187
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Stability Tests
Power Transformer Stability Procedure
Test
Page | 188
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Transformer Technical Data (Name Plate)
- For example: this name plate for power transformer installed at Traction_1 SS
-
Page | 189
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) Test Equipment’s Used:
Note: Used ODEN Tester for primary injection at GIS Busbar because
high load impedance and we need high injected current.
S.N
Type
1
AC Generator
2
Clamp meter
Make
Calibration date
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Additional Safety Precautions:
1- LOCKOUT RELAY should be isolated and ensure NO POSSIBLE tripping during the test.
2- Check that any high impedance protection (ex. Transformer REF protection) is shorted
before primary injection on their CT Cores.
3- Any CT cores not related to Transformer protection should be shorted for safety.
4- Check that Transformer is short-circuited at the LV side after the transformer LV Side CT
for differential protection.
5- Isolate the Differential Protection Trip Links
6- The injected current should not exceed the smallest turns ratio CT.
7- Check the balance and phase sequence of the three phases power supply at the HV side of
the transformer.
Page | 190
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Power Transformer Stability Test
3.1.1) Purpose of test:
- The objective of this test is confirmed that the differential relay or REF
relay doesn't operate at normal conditions even though load currents are
high, where it should operate when a fault occurs in its zone.
3.1.2) Work Instructions/Test Procedure:
➢ IMPORTANT POINTS should be CONFIRMED Before starting the
Busbar stability test:
1- Make sure that star point (of all CTs used for Transformer Differential
Protection) are towards power transformer, and it is grounded only in the
transformer protection panels.
2- Confirm the capability of the injection kit. The injection of primary current
shall satisfy and exceed 50% of secondary current that will operate the
transformer relay during sensitivity.
3- The clamp meter should have a direction indication, and this direction
must be taken into consideration when measurements.
4- CT loop and primary injection tests should be completed for High
voltage and Low voltage sides.
5- Make sure there is no more than one earthing point on the CT at the
secondary circuit for HV side and LV sides.
6- The final settings must be applied and tested before the stability test.
7- Check that all associated CT cores are having the same Knee point
nearly for high voltage side and low voltage sides for high impedance
protection.
8- For Transformer Differential Stability Test for 3 Phases, Use first tap,
middle tap & last tap.
9- Good earth of:
- The Generator.
- The Transformer.
- The shield of the cables.
10- The correct size of connected testing cables.
11- Determine working zones and places and preventing any person to be in
these zones.
Page | 191
Inspection Test Plan
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
12- Suitable MCB for 3-phase supply.
13- CT terminal blocks must be checked and tightness well.
14- All REF (Restricted Earth Fault) relays must be removed or its CT
terminal shorted.
15- Check the Phase Sequence of the 3-Phase Supply.
16- Test equipment and tools:
- Calibrated multi-meters.
- Calibrated testers for measure current and phase angle.
17- If we Connect 3 phase AC voltage supply to the Low voltage side of the
transformer and make a short circuit on High voltage side to get more
current at low voltage side to be sensitive for protection relays.
Page | 192
Inspection Test Plan
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• For Transformer Differential Stability Test for 3 Phases, Use first
tap, middle tap & last tap:
I1=I2
&
Ǿ1-Ǿ2=180˚
• For Transformer Differential Sensitivity Test Swap 3 phase of CT
Polarity. Use middle tap only:
I1=I2
&
Ǿ1-Ǿ2=0˚
- Thesis results values for our example of power transformer for
illustration only.
Page | 193
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
18- Normalize the reversed CT.
19- Normalize the trip isolation links.
20- Normalize the shorted CT cores.
21- Evaluate results on test format tables as below:
➢ Note:
Stability Test:
• 180-degree phase Shift between HVS & LVS
• For YnD11 Transformer the phase shift (180 + 30)
• On reversing the CT Star point it is a differential trip state
Page | 194
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Traction Transformer
Stability Procedure Test
Page | 195
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Transformer Technical Data (Name Plate)
- For example: this name plate for Traction transformer installed at Traction_1 SS
-
-
Page | 196
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) Test Equipment’s Used:
Note: Used ODEN Tester for primary injection at GIS Busbar because
high load impedance and we need high injected current.
S.N
Type
1
AC Generator
2
Clamp meter
Make
Calibration date
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Additional Safety Precautions:
1- LOCKOUT RELAY should be isolated and ensure NO POSSIBLE tripping during the
test.
2- Check that any high impedance protection (ex. Transformer REF protection) is shorted
before primary injection on their CT Cores.
3- Any CT cores not related to Transformer protection should be shorted for safety.
4- Check that Transformer is short-circuited at the LV side after the transformer LV Side CT
for differential protection.
5- Isolate the Differential Protection Trip Links
6- The injected current should not exceed the smallest turns ratio CT.
7- Check the balance and phase sequence of the three phases power supply at the HV side of
the transformer.
Page | 197
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Traction transformer Stability Test
3.1.1) Purpose of test:
- The objective of this test is confirmed that the differential relay or REF
relay doesn't operate at normal conditions even though load currents are
high, where it should operate when a fault occurs in its zone.
3.1.2) Work Instructions/Test Procedure:
➢ IMPORTANT POINTS should be CONFIRMED Before starting the
Busbar stability test:
1- Make sure that star point (of all CTs used for Transformer Differential
Protection) are towards traction transformer, and it is grounded only in
the transformer protection panels.
2- Confirm the capability of the injection kit. The injection of primary
current shall satisfy and exceed 50% of secondary current that will
operate the transformer relay during sensitivity.
3- The clamp meter should have a direction indication, and this direction
must be taken into consideration when measurements.
4- CT loop and primary injection tests should be completed for High
voltage and Low voltage sides.
5- Make sure there is no more than one earthing point on the CT at the
secondary circuit for HV side and LV sides.
6- The final settings must be applied and tested before the stability test.
7- Check that all associated CT cores are having the same Knee point
nearly for high voltage side and low voltage sides for high impedance
protection.
8- For Transformer Differential Stability Test for 3 Phases, Use first tap,
middle tap & last tap.
9- Good earth of:
- The Generator.
- The Transformer.
- The shield of the cables.
10- The correct size of connected testing cables.
11- Determine working zones and places and preventing any person to be in
these zones.
Page | 198
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
12- Suitable MCB for 3-phase supply.
13- CT terminal blocks must be checked and tightness well.
14- All REF (Restricted Earth Fault) relays must be removed or its CT
terminal shorted.
15- Check the Phase Sequence of the 3-Phase Supply.
16- Test equipment and tools:
- Calibrated multi-meters.
- Calibrated testers for measure current and phase angle.
17- IF We Connect 2 phase AC voltage supply to Low voltage side of the
transformer and make a short circuit on High voltage side.
Page | 199
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 200
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 201
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 202
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• For Transformer Differential Stability Test for 3 Phases, Use first
tap, middle tap & last tap:
I1=I2
&
Ǿ1-Ǿ2=0˚
• For Transformer Differential Sensitivity Test Swap 3 phase of CT
Polarity. Use middle tap only:
I1=I2
&
Ǿ1-Ǿ2=180˚
18- Normalize the reversed CT.
19- Normalize the trip isolation links.
20- Normalize the shorted CT cores.
21- Evaluate results on test format tables as below:
Thesis results values for our example of traction transformer for
illustration only.
Page | 203
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Note:
Stability Test:
• 180-degree phase Shift between HVS & LVS
• For Vv0/Vv6 Transformer the phase shift (0)
• On reversing the CT Star point it is a differential trip state
Page | 204
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Busbar Stability Procedure
Test
Page | 205
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: Used ODEN Tester for primary injection at GIS Busbar because
high load impedance and we need high injected current.
S.N
Type
Make
1
ODEN
Megger
2
Clamp meter
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
- Use series connection when you want a high voltage at a high load impedance.
- Use parallel connection when you need a low internal impedance to be able to
generate high current.
Page | 206
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
Busbar Stability Test
2.1.1) Purpose of test:
- This test is prepared to carry out various pre- commissioning tests to be
conducted in systematic manner for CT to ensure the healthiness and
performance of the equipment.
- Make sure all polarity of CTs is ok and BB protection function operates
successfully during actual fault.
2.1.2) Work Instructions/Test Procedure:
➢ IMPORTANT POINTS should be CONFIRMED Before starting the
Busbar stability test:
1- Final setting for Busbar protection relays should be applied and tested.
2- Make sure that star point (of all CTs used for Busbar Protection) are
towards Busbar, and it is grounded only in the Busbar protection panels.
3- CT loop test should be checked (High Impedance Busbar)
4- Secondary injection for Busbar CTs should be completed.
5- Resistors (Series and Shunt) settings should be done accurately as per
final setting (High Impedance Busbar).
6- CT supervision contacts shall be isolated. (High Impedance Busbar).
7- Confirm the capability of the injection kit. The injection of primary
current shall satisfy and exceed 50% of secondary current that will
operate the Busbar relay during sensitivity.
8- Confirm that the auxiliary contacts of the double busbar isolators are of
Early make, Late break type.
9- The clamp meter should have a direction indication, and this direction
must be taken into consideration when measurements.
➢ Core Identification Test:
• In this test we confirm the CT secondary connection.
• Inject low current (for example:50A).
• Use small jumper to short CT secondary from CT box, the
measurement will be gone at panel.
• Repeat this test for all phases and cores.
Page | 207
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Short and isolate facility Test:
• We confirm the CT short and isolate facility for correct connection.
• Inject low current (for example:50A).
• Short CT links then isolate the external wiring to confirm CT circuit
will not be opened.
➢ Single earth point (SEP) Test:
• For all CT loops, each CT loop must have one (SEP), otherwise
secondary current will be divided.
• Open earth point and check with buzzer that there is no earth link is
closed, then close on point.
➢ Primary injection Test:
• After confirming all previous steps, CT is ready now to the primary
injection test.
• Choose two points to connect two terminals of ODEN Cables.
• Make sure chosen closed path has two specified CTs to check them.
• Use ODEN kit to inject current.
• Measure the secondary current in all loops up to the end of this loop.
• Inject primary current between feeders 1 and 2 For R Phases,
• Measure currents and phase angles in all panels for discrimination zone
(for BB 1 & 2) & check zone.
• For BB Stability Test:
I1=I2
&
Ǿ1-Ǿ2=180˚
• For Sensitivity Test, Swap one of CT polarity:
I1=I2
&
Ǿ1-Ǿ2=0˚
• Repeat steps for Y and B phases for all feeders and Bus
Page | 208
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Example for GIS 220/27.5/22Kv LRT SS:
\
Page | 209
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 210
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
(REF) Restricted Earth Fault
Stability Procedure Test
Page | 211
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Transformer Technical Data (Name Plate)
- For example: this name plate for power transformer installed at Traction_1 SS
Page | 212
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) Test Equipment’s Used:
Note: Used ODEN Tester for primary injection at GIS Busbar because
high load impedance and we need high injected current.
S.N
Type
Make
1
ODEN
ODEN
2
Clamp meter
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
- Use series connection when you want a high voltage at a high load impedance.
- Use parallel connection when you need a low internal impedance to be able to
generate high current.
Page | 213
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Additional Safety Precautions:
1- LOCKOUT RELAY should be isolated and ensure NO POSSIBLE tripping during the test.
2- Check that any high impedance protection (ex. Transformer REF protection) is shorted
before primary injection on their CT Cores.
3- Any CT cores not related to Transformer protection should be shorted for safety.
4- Check that Transformer is short-circuited at the LV side after the transformer LV Side CT
for differential protection.
5- Isolate the Differential Protection Trip Links
6- The injected current should not exceed the smallest turns ratio CT.
7- Check the balance and phase sequence of the three phases power supply at the HV side of
the transformer.
Page | 214
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Restricted Earth Fault (REF) Stability Test
3.1.1) Purpose of test:
- Earth fault is the unintended fault between the live conductor and the
earth. It also occurs, because of the insulation breakdown. When the
fault occurs, the short-circuit currents flow through the system, and this
current is returned through the earth or any electrical equipment. This
fault current damaged the equipment of the power system and
interrupted the continuity of the supply.
- The earth fault can be dispersed by using the restricted earth fault
protection scheme. The earth fault protection scheme consists of the
earth fault relay, which gives the tripping command to the circuit
breaker and hence restricted the fault current.
- The objective of this test is confirmed that the REF relay doesn't
operate at normal conditions even though load currents are high, where
it should operate when a fault occurs in its zone.
3.1.2) Work Instructions/Test Procedure:
1- Choose two points to connect two terminals of ODEN Cables.
2- Make a bridge between Transformer windings R, S&T.
3- Make sure chosen closed path has two specified CTs to check them.
4- Use ODEN kit to inject current.
5- Measure the secondary current in all loops up to the end of this loop.
6- Inject 50 A from primary test kit ODEN between CT phase R & ground.
7- Repeat the previous step with phase S & ground, then phase T & ground.
Page | 215
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• For REF Stability Test for R Phase:
IR=IN
&
ǾR-ǾN=180˚
• For Transformer Differential Sensitivity Test Swap 3 phase of CT
Polarity. Use middle tap only:
I1=I2
&
ǾR-ǾN=0˚
8- Evaluate test results and fill it at test formats tables.
- Thesis results values for our example of power transformer for
illustration only.
Page | 216
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
9- Normalize the reversed CT.
10- Normalize the trip isolation links.
11- Normalize the shorted CT cores.
➢ Note:
- Stability Test:
• 180-degree phase Shift between HVS & LVS
• For YnD11 Transformer the phase shift (180 + 30)
• On reversing the CT Star point it is a differential trip state
Page | 217
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
HV Under Ground Feeder
Stability Procedure Test
Page | 218
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: Used INGAVAR Tester for primary injection at GIS Busbar
because high load impedance and we need high injected current.
S.N
Type
Make
1
INGVAR
Megger
2
Clamp meter
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 219
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
HV Under Ground Feeder Stability Test
2.1.1) Purpose of test:
- The objective of this test is confirmed that the differential relay doesn't
operate at normal conditions even though load currents are high, where it
should operate when a fault occurs in its zone.
2.1.2) Work Instructions/Test Procedure:
1- IMPORTANT POINTS should be CONFIRMED Before starting the
stability test:
• Make sure that star point (of all CTs used for Underground Differential
Protection) are towards underground cable, and it is grounded only in the
feeder protection panels.
• Confirm the capability of the injection kit. The injection of primary current
shall satisfy and exceed 50% of secondary current that will operate the
transformer relay during sensitivity.
• Make sure there is no more than one earthing point on the CT at the
secondary circuit.
• The final settings must be applied and tested before the stability test.
• Check that all associated CT cores have the same Knee point nearly for
high voltage side and low voltage sides for high impedance protection.
• Good earth of:
- The INGVAR tester
- The shield of the cables.
• The correct size of connected testing cables.
• Determine working zones and places and prevent any person to be in these
zones.
• Suitable MCB for 3-phase supply.
• CT terminal blocks must be checked and tightness well.
2- Choose the selected path as shown in the figure below and inject between
two phases of bay from TSS2 and TSS1 and we will perform these steps:
Page | 220
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
For TSS2:
o Open Q1&Q2 of bus bar at TSS2.
o Remove earth jumper bar of earth switch disconnector Q51 or Q52
to access for INGAVAR outlet cable.
o Close Q51 or Q52 to inject from it which are circled.
o Close Q0 (circuit breaker) which is circled.
o Close Q9 line disconnector which is circled.
o Open all earth disconnectors which are not related test.
o We inject from two bays D11 and D14 at TSS2 to D02 and D05
bays at TSS1.
For TSS1:
o Open Q1&Q2 of bus bar at TSS1.
o Keep earth jumper bar of earth switch disconnector Q51 or Q52 and
remove connection between it and earth bars of GIS body to close
back the injection loop between phases: R&Y for example.
o Close Q51 or Q52 to receive injection current from it.
o Close Q0 (circuit breaker) which is circled.
o Close Q9 line disconnector which is circled.
o Open all earth disconnectors which are not related test.
3- Make sure chosen closed path has two specified CTs to check them.
4- Use INGAVAR kit to inject current.
5- Measure the secondary current in all loops up to the end of this loop.
6- Inject 5 A from primary test kit INGAVAR between CT phase R&Y.
7- Measure reading of secondary currents at local and remote relays for this bay
and check for differential and restraint current values which at normal injection
current value as 15A that restraint current greater than differential current.
8- Swap two terminal block from test plug at protection panel or LCP of this
feeder to simulate fault case.
9- Measure the differential current which greater than restraint current and two
local and remote relays will be trips by differential protection function if
differential current equal or greater than minim pickup setting value.
10- Repeat the previous step with phase Y&B, then phase B&R.
Page | 221
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
For UG Stability Test:
I1=I2
&
Ǿ1-Ǿ2=180˚
For Sensitivity Test, Swap one of CT polarity:
I1=I2
&
Ǿ1-Ǿ2=0˚
➢ For TSS2: This figure is taken from TSS2 GIS SLD
Page | 222
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ For TSS1: This figure is taken from TSS1 GIS SLD
Page | 223
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Stability Condition between D11 @TSS2 and D02 @TSS1
Phase
D11
D02
CT Ratio
1250/1A
1250/1A
IA Diff
IA Rest
PH-A
---
---
---
---
---
---
PH-B
15 ∟0̊
15 ∟180̊
PH-C
15 ∟180̊
15 ∟0̊
IB Diff
IC Diff
---0.00A
----
- This values from NR protection Relay (PCS-931)
Page | 224
IB Rest
--31.38A
---
IC Rest
----
1.596A
29.812A
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Un-Stable Condition between D11 @TSS2 and D02 @TSS1
➢ Swap between Phase B and Neutral at TSS2 side (local Relay)
Phase
D11
D02
CT Ratio
1250/1A
---
1250/1A
---
PH-B
replaced By
N (3I0)
15 A∟0̊
15 A∟0̊
PH-C
15 A∟0̊
15 A∟0̊
PH-A
IA Diff
IA Rest
---
---
---
---
IB Diff
IC Diff
---14.122A
----
- This values from NR protection Relay (PCS-931)
Page | 225
IB Rest
--14.122A
---
IC Rest
----
1.596A
32.95A
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Meters Tests
Digital Meters Test
Page | 226
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Digital Meter Technical Data (Name Plate)
Manufacturer
Model
Bay No.
Rated Voltage
110 V DC/AC
Accuracy Class
0.5
VT Ratio
CT Ratio
2) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
FREJA 300
Megger
2
Multi-Ammeter
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 227
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical and Visual Inspection Test:
#
DESCRIPTION
1.
Inspect for physical damage or defects.
2.
Check test plug for correct function.
3.
Verify all connections as per approved drawing.
4.
Check tightness of all connections.
5.
Check all display functions.
REMARKS
(OK / NOT OK)
Secondary Current and Voltage Injection Test:
3.2.1) Purpose of test:
- Check the CTs and VTs connections and values are corrected.
- Make sure all injected values are corrected at metering Panels.
- Make sure for (P-Q-PF-S) values are corrected and match with current and
voltage ratios.
➢ Criteria: As per FAT):
Error % = [(Measured value- actual value)/actual value] *100
Error range %= ±5 as per meter technical data.
3.2.2) Work Instructions/Test Procedure:
1- Connect 4 wire of FREJA tester for 4 points of CT from schematic DWG.
2- Connect 4 wire of FREJA tester for 4 points of VT from schematic DWG.
Page | 228
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3- Make sure that one specified (SEP) single earth point.
4- Inject different values of current to make sure no swape between
external cores of cable.
5- Evaluate test results and compare it by FAT results.
➢
Current Injection:
Injected one value for illustration only:
Applied Current (A)
primary
secondary
Measured Current
(A)
XCT:30
250
0.25
249
-0.4
S
XCT:31
250
0.25
249
-0.4
T
XCT:32
250
0.25
249
-0.4
N
XCT:33
Measured Voltage
(kV)
Error %
Phase
Injection Point Location
R
➢
Error %
-
Voltage Injection:
Injected one value for illustration only:
Applied Voltage
Primary Secondary
(kV)
(V)
Phase
Injection Point Location
R
XVT:6
5.77
28.86
5.76
-0.17
S
XVT:7
5.77
28.86
5.76
-0.17
T
XVT:8
5.77
28.86
5.76
-0.17
N
XVT:20
-
➢ Power Readings:
V ° Phase Angel
P
Q
P. F
0
34.62
0
1
180
-34.64
0.04
1
90
0.02
34.64
0
270
-0.02
34.62
0
Page | 229
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Energy Meter Procedure Test
Page | 230
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Digital Meter Technical Data (Name Plate)
Panel Name
K1-4
C.T Ratio
750/1
Make
CEWE
P.T Ratio
20000/100
Type No.
PROMETER100
Accuracy Class
0.2S
Serial No.
WP026369
Scale Range
Drwg
Sheet No.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
FREJA 300
Megger
2
Multi-Ammeter
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 231
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical and Visual Inspection Test:
TEST
NO:
DESCRIPTION
1.
Inspect for physical damage or defects.
2.
Check test plug for correct function.
3.
Verify all connections as per approved drawing.
4.
Check tightness of all connections.
5.
Check all display functions.
CHECKED
Secondary Current and Voltage Injection Test:
3.2.1) Purpose of test:
- Check the CTs and VTs connections and values are corrected.
- Make sure all injected values are corrected at metering Panels.
- Make sure for (P-Q-PF-S-KWH-MVARH) values are corrected and
match with current and voltage ratios.
➢ Criteria: As per FAT):
Error % = [(Measured value- actual value)/actual value] *100
Error range %= ±5 as per meter technical data.
3.2.2) Work Instructions/Test Procedure:
1- Connect 4 wire of FREJA tester for 4 points of CT from schematic DWG.
2- Connect 4 wire of FREJA tester for 4 points of VT from schematic DWG.
3- Make sure that one specified (SEP) single earth point.
Page | 232
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
4- Inject different values of current to make sure no swape between
external cores of cable.
5- Evaluate test results and compare it by FAT results.
➢
Current Injection:
Injected one value for illustration only:
PHASES
MEASURED CURRENT
INJECTED
Sec
CURRENT
(A)
A
A-N
0.25
B-N
0.5
C-N
1
➢
SCALE
VOLTAGE (V)
50 %
28.86
100 %
57.73
Page | 233
B
(A)
%age
ERROR
C
Voltage Injection:
Injected one value for illustration only:
APPLIED Sec
Ph-N
[
EXPECTED
CURRENT
EXPECTED
VOLTAGE
(KV)
Ph-N
MEASURED VOLTAGE
% ERROR
(KV)
A-N
B-N
C-N
A-N
B-N
C-N
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Power Readings:
-
Active Power
Reactive Power
Apparent Power
Sec Ph-N
Voltage
(V)
Injected
Sec
Current
(A)
Phase
Angle
1
57.73
1
0
2
57.73
1
180
3
57.73
1
90
4
57.73
1
270
S.#
(MW) =√𝟑 VI Cos Φ
(MVARH) =√𝟑 VI Sin Φ
(MVA) =√𝟑 VI
EXPECTED VALUE
MW
MVAR
MVA
MEASURED VALUE
P.F
MW
MVAR
%age ERROR OF POWER MEASURMENT
S.#
MW
1
2
3
4
Page | 234
MVAR
MVA
MVA
P.F
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SF6 Gas Tests
SF6 Analysis Procedure Test
Page | 235
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: Used 3-038R-R DILO Multi-Analyzer SF6 Tester or another tester
for GIS compartments or any SF6 SWGR.
S.N
Type
Make
1
DILO MULTI-ANALYZER
DILO
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 236
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) Check List:
#
TEST DESCRIPTION
1.
Inspect for physical damage or defects.
2.
Check nameplate information for correctness.
3.
Inspect enclosures for proper alignment and foundation fixing
and grounding.
4.
Check quality of paintwork.
5.
Ensure that all special tools and equipment are provided as
specified and have proper storage.
6.
Ensure that gas-handling cart (if provided) operates correctly
and that special filling and degassing fittings are provided and
have proper storage.
7.
Check each gas section filled to correct rated pressure.
8.
Check SF6 gas at each gas section for air and moisture content
after filling at rated pressure.
9.
Gas leak test of all flanges and joints after erection and filling.
Calibrate gas pressure (density) gauges. Check the gauges
10. have correct, legible and readable scales.
11. Check the gauges are ambient temperature compensated.
12. Verify that all operating devices are correctly labeled.
Page | 237
REMARKS
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
SF6 Analysis Test
3.1.1) Purpose of test:
- To verify the quality and condition of the gas in the equipment prior to
the latter being put into service; typically, SF6 percentage and humidity
are measured, to determine if SF6 decomposition products are present,
though normally the result should always be below the permitted levels
for re-used.
- Methods of Testing:
• There are two main concepts in which you can have your SF6 gas tested.
Field-level gas analysis can be completed with a lightweight portal multianalyzer, or you can collect and send out your samples to a lab. Sending
samples to a lab is the more accurate option but has drawbacks. One is the
timeframe it can take to receive results. It is not uncommon for it to take
days/weeks to receive an analysis report.
• Second is the risk of human error contaminating the sample while
capturing the sample. With a limited number of samples, you can draw out,
you have fewer chances of successfully collecting an accurate sample. This
leads us to the second concept, and usually most preferred. Testing the gas
quality with a portable multi-analyzer is generally the industry standard.
You are guaranteed limitless, accurate results within minutes if you use
DILO zero-emission equipment or services.
3.1.2) Work Instructions/Test Procedure:
1- Make sure that test equipment and Tested panels are properly grounded.
2- Check the power supply source for equipment is stable and safe
3- Check that device/equipment under test is isolated and secured.
4- After test completion, return all removed wiring, connections to their
original status.
5- Evaluate results for each compartment and comparing it with FAT results.
6- Filling results on table below as test report and repeate this steps for all bays.
Phase
BAY
Dew Point
Gauge
SO2
(°C)
N
Page | 238
n
Pressure
Percentage
(100%)
R
S
T
(ppmv)
MPa
Rel
Remarks
(OK/NOT OK)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
SF6 Gauge Procedure Test
Page | 239
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: we use multimeter and special tool to get 1st and 2nd stage or each
gauge pressure for each compartment of GIS or SF6 SWGR.
S.N
Type
Make
Calibration date
1
Multimeter
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
2) TESTS:
SF6 Gauge Test
2.1.1) Purpose of test:
- SF6 gas medium is more important for each compartment of GIS or SWGR so we
need to check for all its conditions.
- Check for all contacts of 1st and 2nd stage for all gauge pressure meter which work
successfully.
- Make sure for 1st stage alarm that blocking close for circuit breaker.
- Make sure for 2nd stage alarm that block trip for two trip coils of circuit breaker.
➢ Criteria: The test done according to the FAT procedure and results
referred to the FAT criteria.
3.3.2) Work Instructions/Test Procedure:
1- The test was proceeding locally by discharging the SF6 gas in the indicator
compartment and check the performance of SF6 gauge.
2- The following figure showing the steps of gas discharging by closing valve
1 then open valve 2 using special tool.
3- The CB was checked for operation (close/open) in case of blocking
condition in case of Lock and Unlock position from LCC.
4- All alarms were checked at local control cabinet (LCC).
No.
Bay
Gauge
Pressure 1 Alarm (MPa)
R
Meas.
1
n
Page | 240
S
Act.
Meas.
Low Pressure Lock 1
(MPa)
R
S
T
Act.
Meas.
Act.
Meas.
Act.
Meas.
T
Act.
Meas.
Remarks
(OK/NOT
OK)
Low Pressure Lock 2
(MPa)
R
S
Act.
Meas.
Act.
Meas.
T
Act.
Meas.
Act.
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
MV Cables Tests
VLF Procedure Test
Page | 241
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
Megger
Megger
2
VLF Sinus 45Kv
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Additional Safety Precautions:
• Before testing, safety area should be installed around the H.V
Cable. (Clearance: 4m).
• Appropriate display device (Warning light, Warning plate) should
be installed to notify of the testing.
• The customer (or his representative at the substation) shall
instruct to the test personnel on safety work procedures at
substation, and safety during its commissioning, and shall ensure
the
obedience.
• Unauthorized persons are not strictly allowed to stay in SWGR room
during tests.
Page | 242
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
Measurement of insulation Resistance Test:
Between main circuit and earth
2.1.1) Purpose of test:
- Check quality of insulation resistance before performing high pot test and
comparing it by name plate values or FAT results if its accepted.
➢ Applied Voltage: 5000V DC
➢ Criteria: R≥1GΩ as per FAT results.
2.1.2) Work Instructions/Test Procedures:
1- The cables must be removed from the Busbar.
2- Conduct testing as per below connection diagram with applied
voltage of 5kV DC from the IR/Capacitance Tester for a duration
of 1 minute.
Page | 243
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3- Between each main phase conductor and (earth-sheath+earth) shall
be measured by using 5kV Insulation resistance test kit.
4- Before and after high voltage test.
5- Evaluate results on table.
phase
Sheath
(R)/E
Sheath
(S)/E
Sheath
(T)/E
R/sheath+E
S/sheath+E
T/sheath+E
Applied voltage
(DC)
1 KV for
1 min
1 KV for
1 min
1 KV for
1 min
5 KV for
1 min
5 KV for
1 min
5 KV for
1 min
Megger before
VLF(G.Ω)
Megger after
VLF(G.Ω)
status






➢ Note: Make sure results of insulation resistance after high voltage test
is less than before it.
➢ Note:
- Measurement values may vary depending on the measurement time.
- Namely, Measurement values may vary due to differences in the
moisture of the morning and afternoon.
Page | 244
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
High Voltage Test:
2.2.1) Purpose of test:
- Voltage withstands tests need to be made between each energized phase and the
grounded enclosure. For enclosures containing all three phases, each phase needs
to be tested, one at a time, with the enclosure and the other two phases grounded.
Before voltage withstand tests are initiated, all power transformers, surge
arresters, protective gaps, power cables, overhead transmission lines, and voltage
transformers need to be disconnected. Voltage transformers may be tested up to
the saturation voltage of the transformer at the frequency of the test.
2.3.3) Work Instructions/Test Procedures:
1- The cables must be removed from the Busbar.
2- Inject High voltage 3uo for a duration of 1 hr. for each phase. Refer to the
below image:
3- Repeat the above Procedure for the remaining 2 phases Y and B
4- Record the Leakage current for each phase.
5- The measured leakage current should be as per the factory test value
6- VLF TEST with applied voltage 34.6 KV & frequency 0.1 HZ.
Leakage current
Capacitance
Sequence
Time
(mA)
(micro.F)
R+S+T/E
Page | 245
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Batteries Tests
Battery Discharge Procedure
Test
Page | 246
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Battery Cell Technical Data:
Manufacturer
Nominal Cell Voltage
Dimensions
Terminal Size
Max Weight
Container Material
Type
2) Test Equipment’s Used:
Note: Used tester types below or approved testers by consultant.
S.N
Type
Make
1
Multimeter
Megger
2
External Loads
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 247
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) Tests:
Battery Discharge Test:
3.1.1) Purpose of test:
- The purpose of the test is to determine the true capacity of the
battery by finding the time that it takes the battery to reach the end of
discharge voltage and compare it to the expected time from the battery
specifications. The ratio between the resulting time and the expected time
defines the capacity of the battery in percentages.
3.1.2) Work Instructions/Test Procedures:
1- Ensure that the Battery Bank to be tested has not been discharged within
the last 7 days before performing Battery discharge test.
2- Measure the Voltage of the battery bank and each of its battery cell while
on float mode (battery being charged).
3- Disconnect the battery charger from the battery bank and perform
measurement of initial voltage of each of the battery cells and the battery
bank as shown above.
4- Select the discharge rate based upon the battery capacity (ampere-hour)
and the time the test shall be carried out for 3 hours.
5- Start discharge process for 3 hours individually and note total
voltage and cell voltage for each phase then fill down all results at
test format tables as shown below.
Page | 248
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢
Measuring before Discharging:
-
Time: 09:30
Cell
n
Total Volt:
V
Cell
n
Cell Volt
Cell Volt
➢ Measuring for the first hour
-
Time: 10:30
Cell
n
Total Volt:
V
Current:
A
Cell
n
Cell Volt
Cell Volt
➢ Measuring for the second hour
-
Time: 11:30
Cell
n
Total Volt:
V
Current:
A
Cell
n
Cell Volt
Cell Volt
➢ Measuring for the third hour
-
Time: 11:30
Cell
n
Total Volt:
V
Cell Volt
Current:
A
Cell
n
Cell Volt
6- Generate finally graph shows relation between total voltage and
discharging hours
Page | 249
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Static Var Generator Tests
SVG Procedure Tests
Page | 250
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) SVG (Static Var Compensator) Tests:
1- CONTACT RESISTANCE TEST.
2- CIRCUIT BREAKER TIMING TESTS.
3- SCHEME CHECK.
4- PLC TEST.
5- CURRENT TRANSFORMERS TEST.
6- STEP-DOWN POWER TRANSFORMER TEST.
7- HIGH VOLTAGE INSULATION TEST.
8- PROTECTION FUNCTION TEST.
9- COLD RUN TEST.
10- POWER QUALITY ANALYZER IMAGE BEFORE ENERGIEZ.
11- HOT RUN TEST.
12- POWER QUALITY ANALYZER IMAGE AFTER ENERGIEZ.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers by consultant.
S.N
Type
Make
1
Megger 5K VDC
Megger
2
CPC 100
OMICRON
3
Micro-ohmmeter meter
Megger
4
EGIL
Megger
5
HVT-70/50 Tester
6
Freja 300
7
Class (A) Power Quality Analyzer
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
Page | 251
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Contact Resistance Test:
3.1.1) Purpose of test:
- The purpose is to appreciate the status of internal fabrication and
dimension of conductors which lie in GIS compartment indirectly
thereby ensuring good contact.
3.1.2) Work Instructions/Test Procedures:
1- Select path for injection current start and end point.
2- Connect cables of ohmmeter tester at selected path.
3- Start test be increase gradually injected current until 100A value.
4- Evaluate results for all selected paths.
5- Compare between measured values and FAT results if accepted.
6- Evaluate all results values and filling down test table formats.
Page | 252
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Circuit Breaker Timing Test:
3.2.1) Purpose of test:
- This test is used on medium and high-voltage circuit breakers and
provides information as to whether the operating mechanism of the
circuit breaker is operating properly or not by measuring the closing
and opening time of the breaker contacts.
- This test can be used to determine the opening and closing speeds of the
breaker, the interval time for closing and tripping and the contact
bounce. The test provides information that can be used to detect
problems such as weak accelerating springs, defective shock absorbers,
dashpots, buffers, and closing mechanisms.
3.2.2) Work Instructions/Test Procedures:
1- Preparing connection of EGIL tester as shown below.
2- Connect external DC supply for closing and tripping coils.
3- Connect wires for closing and tripping coils at schematic DWG.
4- Connect sensing current feedback cable as shown.
5- Evaluate results for each sequence and compared it by FAT results.
6- Repeat same sequence at 85% of voltage supply.
Page | 253
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Current Transformer Tests:
3.3.1) Mechanical Check and Visual Inspection:
3.3.1.1) Purpose of test:
- Make sure that current transformer is ready to test and doesn’t
have any damage parts which prevents perfuming tests.
#
TEST DESCRIPTION
REMARKS
(OK / NOT OK)
13. Inspect for physical damage or defects.
14. Check nameplate information for correctness.
Check that outdoor secondary wiring terminations are installed in moisture
proof enclosures.
16. Check tightness of all bolted connections (torque wrench method).
15.
17. Check that all grounding cables are securely connected.
Check secondary wiring is correctly color coded and size of wires is as
18. specified.
19. Check proper lugs have been used on terminations.
Check CT locations physically and secondary terminal labeling has been
20. done correctly.
3.3.2) Insulation Resistance Test:
3.3.2.1) Purpose of test:
- To determine the equipment in proper condition to put in service.
Results can be kept as record to compare in future and to understand
the trend of insulation during maintenance.
➢ Applied Voltage:
• 5000V DC for Primary – Earth.
• 2500V DC for Primary – Secondary.
• 1000V DC for Secondary - Secondary & Secondary - Earth
➢ Criteria:
As per FAT): More than 2500 MΩ for Primary – Secondary – Earth
More than 2000 MΩ for Secondary - Earth and between secondaries.
➢ Note: This test is performed for GIS/SWG current transformer.
Page | 254
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.3.2.2) Work Instructions/Test Procedure:
1- Connect megger tester as shown below.
2- Apply voltage test value for each connection.
3- Make sure CT secondaries earth connection are disconnected.
4- Make sure GIS/SWG is earthed successfully.
5- Evaluate test results and compare it by FAT results.
Phase: n
Primary
Earth
Core 1
Core 2
Primary - Earth
Page | 255
Core 1
Core 2
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.3.3) Winding Resistance Test:
3.3.3.1) Purpose of test:
- Secondary resistance test is to verify the CT secondary winding
resistance with specified one and no discontinuity in the winding.
- Make sure measured value doesn’t affect on knee voltage value
of current transformer.
➢ The Resistance card is only available if winding resistance
measurement is enabled in the Select Cards page (Default Test
Card Selection or Select Cards soft key in the CT-Object card).
➢ Depending on your selection on the Select Cards page, the
Resistance card shows the parameters and results for the primary
winding resistance measurement or the secondary winding
resistance measurement only, or for both measurements.
➢ Criteria: within +/- 5% of FAT test Reports
➢ Note: CT Analyzer by OMICRON tester is used for all tests of current
transformer.
Page | 256
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.3.3.2) Work Instructions/Test Procedure:
1- Connect CT to CT Analyzer kit as shown in figure below.
2- Make sure terminal slide of secondary wiring is opened.
3- Choose the below tests from tester window.
4- Evaluate results as software file report which is printed later to
attached with main test report.
5- Compare measured values with FAT results.
Page | 257
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.3.4) Turns Ratio-Polarity Test:
3.3.4.1) Purpose of test:
- Make sure measured value of turns ratio is within error % according
to FAT error criteria.
- Make sure polarity of CT is OK for performing succeed stability test.
➢ Criteria: (As per FAT Results).
➢ The Ratio card is only available if it is enabled in the Select Cards
page (Default Test Settings or Select Cards soft key in the CT-Object
card).
➢ The ratio test measures the current ratio of the CT considering the
operating burden (parameter "Burden" in CT-Object card) or the
nominal burden (parameter "VA" in CT-Object card).
➢ For a better understanding of the test results, the most important
settings from the CT-Object card are shown once again in the upper
part of the Ratio card.
➢ Note: Although the test is not performed with the real current, the
test results reflect the current ratio and not the voltage ratio.
➢ Note: Although the test is not performed with the real current, the
test results reflect the current ratio and not the voltage ratio.
3.3.4.2) Work Instructions/Test Procedure:
1- Connect CT to CT Analyzer kit as shown in figure below.
2- Make sure terminal slide of secondary wiring is opened.
3- Choose the below tests from tester window.
4- Evaluate results as software file report which is printed later to
attached with main test report.
5- Compare measured values with FAT results.
Page | 258
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.3.5) Excitation Curve Test:
3.3.5.1) Purpose of test:
- Calculate knee voltage point for current transformer which CT enter
saturation region after this point.
- Make sure that CT excitation curve for metering and protection
core is accepted according to standard.
➢ The excitation graph page shows the graph calculated from the test
results.
➢ To display the excitation graph, press the Exist. Graph soft key in the
Excitation card. The graph shows the r.m.s. terminal/core voltage over
the r.m.s./peak current depending on the selected standard.
➢ Criteria: The %age error for Magnetizing current shall be within +/5% of the factory Test.
➢ ALL OMICRON CT ANALYZER REPORTS ARE PROVIDED.
➢ ALL FAT REPORTS ARE PROVIDED.
3.3.5.2) Work Instructions/Test Procedure:
1- Connect CT to CT Analyzer kit as shown in figure below.
2- Make sure terminal slide of secondary wiring is opened.
3- Choose the below tests from tester window.
4- Evaluate results as software file report which is printed later to
attached with main test report.
5- Compare measured values with FAT results.
Page | 259
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Step Down Transformer Tests:
3.4.1) Mechanical and Visual Inspection Test:
3.4.1.1) Purpose of test:
- Make sure that transformer is ready to test and doesn’t have a
damage part which prevents perfuming tests.
#
TEST DESCRIPTION
REMARKS
(OK / NOT OK)
Inspect for physical damage/defects (see for any cracks, chips, etc. on
21. visible outer layer of the cast resin).
22. Check nameplate for correctness.
23. Check tightness of all bolted connections (torque wrench method).
Check that all grounding is securely connected, including star point
24. neutral.
25. Perform all specific checks per manufacturer instructions
26. Check proper operation of all auxiliary devices (if applicable)
3.4.2) Polarization Index Test:
3.4.2.1) Purpose of test:
- To determine the equipment in proper condition to put in service.
Results can be kept as record to compare in future and to understand
the trend of insulation during maintenance.
➢ Applied Voltage: 5000V DC
➢ Criteria: PI > 1.25
POLARIZATION INDEX (PI) =
10 min Insulation resistance (Meg−ohm) reading
1 min Insulation resistance (Meg−ohm) reading
≥ 1.25.
3.4.2.2) Work Instructions/Test Procedures:
1- Connect megger tester as shown below.
2- Apply voltage test value for each connection.
3- Evaluate test results and compare it by FAT results.
4- Calculate PI value for each connection and make sure that more
than criteria value.
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Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1)HV-LV winding insulation
resistance test
Test
Results
After 1 min
3)LV winding-Ground
insulation resistance test
2)HV winding-Ground insulation
resistance test
Results
After 10 min
PI
Remarks
(OK / NOT OK)
HV – LV
HV – Earth
LV – Earth
3.4.3) Turns-Ratio (TTR) Test:
3.4.3.1) Purpose of test:
- Main purpose of turn ratio test to check for actual turns ratio
which in the range of acceptable error.
➢ The CPC 100 tester is used or any approved suitable tester, the
turns-ratio test can be performed by two types of connections
(1-PH or 3-PH) connections which are available at site and
approved, we use 1st connection.
➢ Criteria: Error ≤ 0.5
1) Single-Phase Test Connection: CPC 100 only with a maximum
output voltage of 2000V.
2) Three-Phase Test Connection: CPC 100 + CP SB1 with a
maximum output voltage of 300V.
Page | 261
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.4.3.2) Work Instructions/Test Procedures:
1- Connect CPC100 connections as shown below.
2- Apply selected test type from CPC100 window.
3- Connect primary winding connections and be careful during test.
4- Evaluate results during each tap.
Tap
Phases
No.
UV
of
UW
taps
VW
Page | 262
Rated Ratio
Measured Ratio
%
Error
Remarks
(OK / NOT OK)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.4.4) DC Winding Resistance Test:
3.4.4.1) Purpose of test:
- Secondary resistance test is to verify the CT secondary winding
resistance with specified one and no discontinuity in the
winding.
➢ The CPC 100 is required or any approved tester. Before
beginning the DC Winding Resistance test, please consider the
following,
➢ The DC Winding Resistance Test should always be the last test
performed on a power transformer.
➢ The DC Winding Resistance test can be performed with the CPC
100 or another approved tester using three methods, which
include:
• 400A DC Method – Recommend for measuring resistances <
50mΩ and (e.g. typically useful for performing a low-voltage
winding resistance measurement)
• 6A DC Method – Recommended for measuring resistances >
50mΩ and <10Ω (e.g. typically useful for performing a highvoltage winding resistance measurement).
• 2-Wire Method – Recommended for measuring resistances >10Ω
only.
➢ Note: make sure that each phase results must same as other
phases within error
3.4.4.2) Work Instructions/Test Procedures :
1- Connect CPC100 connections as shown below.
2- Apply selected test type from CPC100 window.
3- Connect primary winding connections and be careful during
test.
4- Evaluate results during each tap.
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Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Example of the 1ph test connection for Phase-A on the low voltage winding of a Dyn1
transformer.
- High Voltage Side Winding Resistance:
➢ Criteria: As per FAT Results.
➢ Ambient Temperature: 28ᵒC
U V
Tap
Position
Result
(Ω)
Rc @
75 C
(Ω)
V W
FAT R
@ 30 C
(Ω)
Result
(Ω)
Rc @
75 C
(Ω)
W U
FAT R
@ 30 C
(Ω)
Result
(Ω)
Rc @
75 C
(Ω)
FAT R
@ 30 C
(Ω)
No. of
taps
-
Low Voltage Winding Resistance:
➢ Criteria: As per FAT Results.
➢ Ambient Temperature: 28ᵒC
u v
Tap
Position
Rm
(mΩ)
Rc @
75 C
(mΩ)
v w
FAT R
@ 30 C
(mΩ)
Rm
(mΩ)
Rc @
75 C
(mΩ)
w u
FAT R
@ 30 C
(mΩ)
Rm
(mΩ)
1
Notes: this formula is used to calculate winding resistance referred to 75  C.
Rc: Calculated value at 75  C.
Rm: Measurement value which contained a measurement cable.
Ta: Ambient Temperature.
Rc = Rm*(235+75)
(236+Ta)
Page | 264
Rc @
75 C
(mΩ)
FAT R
@ 30 C
(mΩ)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
High Voltage Tests:
3.5.1) Purpose of test:
- To determine the equipment is in proper condition to put in service, after
installation for which it was designed and to give some basis for predicting
whether that a healthy condition will remain, or deterioration is underway
which can result in abnormally short life.
- Check insulation resistance between CT primary and its cores-between
each core to another – primary to earth and cores to earth and
comparing it by FAT results if its accepted.
➢ Additional Safety Precautions:
• Before testing, safety area should be installed around the H.V
equipment. (Clearance: 4m).
• Appropriate display device (Warning light, Warning plate)
should be installed to notify of the testing.
• The customer (or his representative at the substation) shall instruct to
the test personnel on safety work procedures at substation, and safety
during its commissioning, and shall ensure the obedience.
• Unauthorized persons are not strictly allowed to stay in SWGR room
during tests.
3.5.2) Work Instructions/Test Procedures:
1- It includes panel enclosure, bus bar, CT & breaker / contactor. The
following precautions should be taken care, before starting the test:
- A visual inspection will be made to ensure the surface dust and
moisture has been removed from the component under test.
- Ensure the component is isolated from other connected system,
which may feedback to other components or circuits not under
test.
- A check shall be made to verify the ground for the component
under test and test equipment being connected to system ground.
- CT’s secondary terminals shall be shorted.
- VT’s & Surge arresters shall be isolated from the equipment
under test.
- Mark out test area and assure nobody can enter during test.
- Circuit breakers/contactors should be inserted and closed.
Page | 265
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Bus bars should be fully mounted tightened and shields between
phases & between phases and earth should be in place. Moreover,
bus bar covers should be in place.
- All Earthing switches related to equipment under test should be open.
- Bus bar conductivity test shall be performed.
- Insulation resistance test should be performed before and after the test.
- Instructions of test equipment being used should be followed.
- After each test subject under test should be discharged to ground.
-
HV Test by AC HV Testers for 60 Sec Duration: 1st C.B. is racked in
and closed and al CBs of section are Racked in and Open Position
Phase Applied Voltage
Leakage
Current (mA)
Duration
R
S
18 KV
60 Sec
T
Measurement of insulation Resistance:
3.5.3) Purpose of test:
- Check quality of insulation resistance before performing high pot test
and comparing it by name plate values or FAT results if its accepted.
➢ Applied Voltage: 5000V DC
➢ Criteria: R≥1GΩ as per FAT results.
3.5.4) Work Instructions/Test Procedures:
1- Between main circuit and earth shall be measured by using
5kV Insulation resistance test kit.
2- Before and after high voltage test.
3- All CBs → Closed, All ES & VT → Opened
4- Evaluate results on table
➢ Power Units and Startup Cabinet Compartment:
- Insulation Resistance Test: @ 5KV DC for 1 min duration before HV Test:
R –(S+T+G)
Insulation Resistance
Page | 266
S- (R+T+G)
T – (R+S+G)
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Insulation Resistance Test: @ 5KV DC for 1 min duration After HV Test:
R –(S+T+G)
S- (R+T+G)
T – (R+S+G)
Insulation Resistance
➢ Note: Make sure results of insulation resistance after high voltage test
is less than before it.
➢ Note:
- Measurement values may vary depending on the measurement time.
- Namely, Measurement values may vary due to differences in the
moisture of the morning and afternoon.
PLC Function Test:
3.5.5) Purpose of test:
- To verify that Hardware and Software of the PLC are met the
specifications of the design.
3.5.6) Work Instructions/Test Procedures :
1- Check all PLC inputs, Output, and software logic by simulate or initiate
field signals
2- Check the PLC action in various conditions.
Cold Run Test:
3.5.7) Purpose of test:
- To verify the proper action of the controller at all power system
condition prior to energization.
3.5.8) Work Instructions/Test Procedures:
1- Check all PLC inputs, Output, and software logic by simulate or
initiate field signals
2- Check the PLC action in various conditions.
Hot Run Test:
3.5.9) Purpose of test:
- Energize the system and assess its action.
Page | 267
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Protection Function Test:
3.5.10) Purpose of test:
- To verify the physical condition and electrical characteristics of
protective relays.
- This test is to confirm the above tested relay is properly connected /
interfaced with system that required. This will verify all inputs to
relay and outputs from the relay are properly connected, as it
required. An injection (current/ voltage) shall be made and
- Checked the functions outputs (trip, alarm, indication, control).
Inputs shall be initiated from the source and monitored the proper
outputs from the relay.
Scheme Check Test:
3.5.11) Purpose of test:
- To verify that all panels wiring are correct according to approved
drawings.
3.5.12) Work Instructions/Test Procedures:
1- Operation sequence and interlock verification.
2- Opening and closing operations of switching devices from local and
remote.
3- Tripping of switching devices from protection.
4- Status of switching devices to local and remote.
5- Alarms/indications availability to local and remote.
POWER QUALITY ANALYZER IMAGE BEFORE ENERGIEZ Test:
3.5.13) Purpose of test:
- To check the power system parameters for 24 hours at full load prior to
energization.
POWER QUALITY ANALYZER IMAGE AFTER ENERGIEZ Test:
3.5.14) Purpose of test:
- To check the power system parameters for 24 hours at full load after
energization.
Page | 268
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Protection Relays Tests
PCS-931 Relay Functions Test
Procedures
Page | 269
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Protection Relay Technical Data (Name Plate)
Designation No.
Manufacturer
Type
Function
Model No.
S/N
Aux. DC Supply
Page | 270
PCS-931
NR
Line Feeder Protection
1- Line Differential
2- Distance Protection
3- SOTF
4- Overcurrent
5- Earth fault
6- VT Fail
7- Power Swing
PCS-931
NRJB2134812160030
110 Vdc
CT Rating
1250/1 A
Residual current
VT rating
N/A
220/0.1 KV
Residual voltage
Rated frequency
N/A
50 HZ
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) Test Equipment’s Used:
➢ Note: Used tester types below or approved testers
➢ Note: we use different testers other than OMICRON tester
S.N
Type
Make
1
OMICRON CMC256-6
OMICRON
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
** Example for connection of Freja Device to advanced relays.
Page | 271
Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
** A picture for CMC256-6.
➢ Software will be used for configuration and final setting tests
- We will use the PCS-Explorer V1.1.2 in this instruction.
Page | 272
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that protection relay is good for testing and it doesn’t have
any damage or missing parts.
ITEM
DESCRIPTION
CHECKED
1
Inspect for any physical damage or defects.
2
Verify connections as per approved drawings.
OK
OK
3
Check that serial no. of relay matching with serial no. of display.
OK
Electrical Tests:
3.2.1) Functional Test
ITEM
DESCRIPTION
CHECKED
4
5
Set Clock to local time
Time maintained when Aux. Supply removed
Make Test Mode Enable under commissioning menu to check ALARM LED
Make Test Mode Enable under commissioning menu to check OUT OF SERVICE
LED
Apply any fault condition to check TRIP LED (Red)
Apply Test LEDs under commissioning menu to check all programmable LEDs.
6
Measured FIELD SUPPLY Voltage
1
2
3
Date & time
Between terminals (+ve) – (-ve)
3.2.2) Measurement Test:
- Inject different values for current and voltage to make sure ratio is ok
Phase
Current Injected (A)
R
S
T
Phase
1∟0
1∟240
1∟120
R-N
S-N
T-N
Page | 273
Voltage Injected (V)
57.7∟0
57.7∟240
57.7∟120
Measuring (A)
“Primary Value”
1249.68 ∟0
1250.69 ∟240
1248.11 ∟120
Measuring (v)
“Primary Value”
127.0 ∟0
127.1 ∟240
127.0 ∟120
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Earth Fault Protection (50G/51G/IDMT_ROC) Test
3.3.1) Definite time of EF protection test
3.3.1.1) Purpose of Test
- During normal operation of power system, there is trace
residual current, whereas a fault current flows to earth will
result in greater residual current. Therefore, residual current is
adopted for the calculation of earth fault protection.
- To improve the selectivity of earth fault protection in power
grid with multiple power sources, directional element can be
selected to control earth fault protection. For application
online-transformer unit, second harmonic also can be selected
to block earth fault protection to avoid the effect of
sympathetic current on the protection.
3.3.1.2) Work Instructions/Test Procedures:
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
➢ Protection Setting:
3- Set 50/51G1.Opt_Dir as 0, to make this function not blocked
by directional element. Disable all other block element (set
logic setting as 0), including50/51G1.En_Hm2_Blk、
50/51G1.En_Abnor_Blk 50/51G2.En_CTS_Blk, set
50/51G1.Opt_Curve as 0 to select definite time characteristic.
Set two states in test kit.
Page | 274
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
•
•
•
•
•
State 1 simulates normal condition:
Set Ur/Us/Ut as positive sequence rated voltage Un.
Ir/Is/It set as 0.
This state lasts for 11S (longer than 10S)
State 2 simulates faulty state:
Simulate PG fault, set faulty voltage between 0V and 0.9Un.
Faulty current set as 1.05*50/51G1.3I0_Set, Faulty time set
as 50/51G1.t_Op+50ms.
Inverse time of EF protection test
3.4.1) Purpose of Test
- During normal operation of power system, there is trace
residual current, whereas a fault current flows to earth will
result in greater residual current. Therefore, residual current
is adopted for the calculation of earth fault protection.
- To improve the selectivity of earth fault protection in power
grid with multiple power sources, directional element can be
selected to control earth fault protection. For application
online-transformer unit, second harmonic also can be
selected to block earth fault protection to avoid the effect of
sympathetic current on the protection.
Page | 275
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.4.2) Work Instructions/Test Procedures:
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Set 50/51G1.Opt_Dir=0, to make this function not blocked
by directional element. Disable all other block element (set
logic setting as 0), including 50/51G1.En_Hm2_Blk、
50/51G1.En_Abnor_Blk、50/51G2.En_CTS_Blk, set
50/51G1.Opt_Curve as 1 to select IEC normal inverse
characteristic. Connect the trip BO of relay to the BI of test
kit to measure the operating time. Open Quick CMC
module in Omicron.
- State 1 simulates normal condition:
• Set Ur/Us/Ut as positive sequence rated voltage Un.
• Ir/Is/It set as 0.
• This state lasts for 11S (longer than 10S)
- State 2 simulates faulty state:
• Simulate PG fault, set faulty voltage between 0V and 0.9Un.
• For example, 50/51G1.3I0_Set=1A, 50/51G1.TMS=0.5,
Then the operating time(state:2) will be:
Page | 276
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Overcurrent protection (50P/51P/IDMT_OC)
Definite time of OC protection test
3.5.1) Purpose of Test
- When a fault occurs in power system, usually the fault current
would be very large and phase overcurrent protection operates
monitoring fault current is then adopted to avoid further
damage to protected equipment. Directional element can be
selected to improve the sensitivity and selectivity of the
protection. For application on feeder-transformer circuits,
second harmonic can also be selected to block phase
overcurrent protection to avoid the effect of inrush current on
the protection.
3.5.2) Work Instructions/Test Procedures:
1- Preparing connection of OMICRON tester.
2- Connect probs of current to OMICRON tester.
3- Set 50/51P1.Opt_Dir=0, 50/51P1.En_Hm2_Blk=0, Set
50/51P1.Opt_Curve=0 to use the definite time function, Set two
states in test kit:
- State 1 simulate normal state:
• Set Ur/Us/Ut as positive sequence rated voltage Un.
• Ir/Is/It set as 0.
• This state lasts for 11S (longer than 10S)
- State 2 simulate faulty state:
• Simulate a single-phase fault, Set faulty voltage between 0V and
0.9Un
Page | 277
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Faulty current set as 1.05*50/51P1.I_Set, fault time set as
50/51P1.t_Op+50ms.
➢ Result:
- If the faulty current is 1.05 times of setting, relay will trip, if it is
0.95 time of setting, relay will not trip. If 50/51P1.En_BlkAR set
as 0.
Inverse time of Overcurrent protection Test
3.6.1) Purpose of Test
- During normal operation of power system, there is trace residual
current, whereas a fault current flows to earth will result in greater
residual current. Therefore, residual current is adopted for the
calculation of earth fault protection.
- To improve the selectivity of earth fault protection in power grid with
multiple power sources, directional element can be selected to control
earth fault protection. For application online-transformer unit, second
harmonic also can be selected to block earth fault protection to avoid
the effect of sympathetic current on the protection.
➢ 50/51P/IDMT (Over Current) C/C’s with equations:
Page | 278
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.6.2) Work Instructions/Test Procedures :
1- Preparing connection of OMICRON tester.
2- Connect probs of current to OMICRON tester.
3- Set 50/51P1.Opt_Dir=0, to disable direction block element. Disable
all other block element by set the logic settings as 0,
including50/51P1.En_Hm2_Blk, 50/51P1.En_Abnor_Blk,
50/51P1.En_CTS_Blk, and set 50/51P1.Opt_Curve=1 to select IEC
normal inverse time characteristic. Connect the trip BO of relay to
the BI of test kit to measure the operating time, use to measure the
operating time. Open Quick CMC module in Omicron.
- State 1 simulates normal condition:
• Set Ur/Us/Ut as positive sequence rated voltage Un.
• Ir/Is/It set as 0.
• This state lasts for 11S (longer than 10S)
- State 2 simulates faulty state:
• Change the current and voltage to simulate a single-phase fault,
Then Release The test kit. Test the operating time by inject
different faulty current.
• Take 50/50P1.I_Set=1A, 50/51P1.TMS=0.5 as an example,
the test result of stage 2 is:
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Line Differential Protection (87L) Test
3.7.1) Purpose of Test
- Current differential protection can be used as main protection of
EHV and HV overhead line or cable. It includes phase-segregated
current differential protection and neutral current differential
protection.
- Make sure that protection relay work properly according to its
differential curve with threshold values and tripping values.
- Discriminate tripping and non-tripping regions of its curve.
3.7.2) Work Instructions/Test Procedures:
1- Preparing connection of OMICRON tester.
2- Connect probs of current to OMICRON tester.
3- Prepare calculations of differential function.
4- Calculate local and remote current carefully to inject them and make
sure relay will work successfully.
➢ Current differential protection comprises three elements:
1- DPFC current differential element (2 stages)
2- Steady-state current differential element (2 stages)
3- Neutral current differential element (1 stage)
3.7.3) DPFC Differential Relay.
- DPFC percent differential element only reflects fault components
which can perform a sensitive protection for the transmission line.
Lab test shows that it is more sensitive in the heavy load condition
than the conventional percent differential element.
- 1st Stage Operation Criteria:
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- 2nd Stage Operation Criteria:
]
- Operation characteristics of DPFC Differential Function
Criteria:
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Steady State (Biased 87L) Differential Relay
• Stage 1:
- The pickup value of 87 biased stage 1 is 1.5 times of the pickup value
setting of 87L.I_Biased. The slope is 0.6, enable the 87L_biased
stage 1 function and disable the others. The settings are as follow:
➢ Test of the pickup value
- Use the QuickCMC function of the test kit, set the magnitude of Ir as the
ramp signal, step is 0.01A:
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Notice:
(1) Slowly increase the value of the current lower than the pickup setting
until it reaches the pickup value. The device will trip when the current is
higher than the settings.
(2) The other two phases can be test in the same way.
➢ Differential Characteristic Test
According to the formulas of this function:
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ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- We can calculate a series of threshold values that can simulate relay
operation:
K
IR (A)
ID Calculated
0.6
2
2.5
3
4
5
6
1.5
1.5
1.8
2.4
3
3.6
I1
(Local end)
1.75
2
2.4
3.2
4
4.8
I2
(Remote end)
0.25
0.5
0.6
0.8
1
1.2
R
1.49
1.49
1.79
2.39
2.9
3.59
ID measured
S
T
1.48
1.49
1.48
1.49
1.78
1.77
2.38
2.39
2.8
2.9
3.59
3.58
- Take Phase R differential protection as an example:
• Use the QuickCMC function of the test kit, the phase angle between
two sides is 180°.
• Connect the trip BO of the relay to the BI of the test kit, to stop the
testing automatically when relay trip.
• Set local current Ir as ramp signal, step is 0.01A, step changing time 0.1S.
• Remote current is fixed. Enable Auto Step.
• Tick the function that stop test when the relay trips (BI changes)
• Start the test kit and then click the increase button.
No.1: Local current 1.75A, remote current0.25A, differential current 1.5A, and
restricted current 2A.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Result: After the current of Ir increase up to the threshold value,
differential protection of phase R trip, then the test kit stops and display
operating value.
No.2: Local current 2A, remote current0.5A, differential current 1.5A, and restricted
current 2A.
➢ Result: After the current of Ir increase up to the threshold value,
differential protection of phase R trip, then the test kit stops and display
operating value.
➢ Notice:
- Please refer to Node 1&2 for the other nodes.
- Test the other two phases in the same way.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Steady State (Biased 87L) Differential Relay
• Stage 2:
- The pickup value of 87 biased stage 2 is the same as the pickup value
setting of 87L.I_Biased. The slope is 0.6, enable the 87L_biased stage 2
function and disable the others. The settings are as follow:
➢ Test of the pickup value
- Use the QuickCMC function of the test kit, set the magnitude of Ir as
the ramp signal, step is 0.01A:
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ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Result: After the current of Ir increase up to the threshold value,
differential
protection of phase R trip, then the test kit stops and
display operating value.
➢ Notice:
- Slowly increase the value of the current lower than the pickup setting
until it reaches the pickup value. The device will trip when the
current is higher than the settings.
- The other two phases can be test in the same way.
➢ Differential Characteristic Test
According to the formulas of this function:
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Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- We can calculate a series of threshold values that can simulate relay
operation:
K
IR (A)
ID Calculated
0.6
1.4
1.666
3
4.
5
6
1
1
1.8
2.4
3
3.6
I1
(Local end)
1.2
1.334
2.4
3.2
4
4.8
I2
(Remote end)
0.2
0.3333
0.6
0.8
1.0
1.2
R
1
1
1.79
2.39
2.9
3.59
ID measured
S
T
0.99
0.98
0.99
0.99
1.78
1.8
2.38
2.39
2.89
2.99
3.59
3.6
➢ Take Phase R differential protection as an example:
• Use the QuickCMC function of the test kit, the phase angle between
two sides is 180°.
• Connect the trip BO of the relay to the BI of the test kit, to stop the
testing automatically when relay trip.
• Set local current Ir as ramp signal, step is 0.01A, step changing time
0.1S.
• Remote current is fixed. Enable Auto Step.
• Tick the function that stop test when the relay trips (BI changes)
• Start the test kit and then click the increase button.
No.1: Local current 1.2A, remote current0.2A, differential current 1A, and restricted
current 1.4A.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢
Result: After the current of Ir increase up to the threshold value,
differential protection of phase R trip, then the test kit stops
and display operating value.
No.2: Local current 1.3A, remote current0.333A, differential current 1A, and
restricted current 1.667A.
➢ Result: After the current of Ir increase up to the threshold value,
differential protection of phase R trip, then the test kit stops and display
operating value.
➢ Notice:
- Please refer to Node 1&2 for the other nodes.
- Test the other two phases in the same way.
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Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Zero Sequence Differential Protection (87 Neutral) Test
- The sensitivity of steady-state differential current element is too low for
the slight fault during heavy load, and DPFC current differential element
can only reflect the slight fault during heavy load, but low for the slow
changing fault due to the small change of fault component. Neutral current
differential element can be very sensitive to this kind of fault.
- The pickup value of Zero sequence differential protection (87_Neutral) is
the same as the pickup value setting of 87L.I_Biased. The slope is 0.75,
enable the 87L_Neutral function and disable the others. The settings are as
follow:
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Test of the pickup value
- Use the QuickCMC function of the test kit, set the magnitude of Ir as the
ramp signal, step is 0.01A:
➢ Notice:
- Slowly increase the value of the current lower than the pickup setting
until it reaches the pickup value. The device will trip when the
current is higher than the settings.
- The other two phases can be test in the same way.
Page | 291
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Differential Characteristic Test
According to the formulas of this function:
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Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- We can calculate a series of threshold value which can simulate relay
operation.
K
IR (A)
ID Calculated
0.75
1.2
1.666
3
4
5
6
1
1.001
2.25
3
3.75
4.5
I1
(Local end)
1.1
1.167
2.625
3.5
4.375
5.250
I2
(Remote end)
0.1
0.166
0.375
0.5
0.625
0.75
R
0.98
1
2.24
2.99
3.748
4.5
ID measured
S
T
0.99
0.99
1
0.991
2.25
2.25
2.98
2.9
3.749
3.75
4.5
4.49
➢ Take Phase R differential protection as an example:
- Use the Quick CMC function of the test kit, the phase angle between
two sides is 180°.
- Connect the Trip Bo of the relay to the BI of the test kit, to stop the
test kit automatically when relay trips.
- Set local current Ir as ramp signal, step is 0.01A, step changing time
0.1S.
- Remote current is fixed.
- Enable Auto Step.
- Tick the function that stop test when the relay trips (BI changes).
- Start the test kit and then click the increase button.
No.1: Local current 1.1A, remote current 0.1A, differential current 1A, and restricted
current 1.2A.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Result: After the current of Ir increase up to the threshold value,
differential protection of phase R trip, then the test kit stops and display
operating value.
No.2: Local current 1.167A, remote current 0.166A, differential current 1A, and
restricted current 1.333A
➢ Result: After the current of Ir increase up to the threshold value, differential
protection of phase R trip, then the test kit stops and display operating value.
➢ Notice:
- Slowly increase the value of the current lower than the pickup setting
until it reaches the pickup value. The device will trip when the current is
higher than the settings.
- The other two phases can be test in the same way.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
87 Function blocked by CTS Test
- This function can be enabled or disabled by the logic setting
[87L.En_CTS_Blk].
- If set 87L.En_CTS_Blk=0, after the alarm of CTS issuing, differential
current will trip it reach the pickup differential currents and CTS should
lower than the setting of pickup.
- If set 87L.En_CTS_Blk=1, after the alarm of CTS issuing, differential
protection will never trip even the differential current is very high.
- Set the settings as 87L.I_CTS > 87L.I_Biased. Enable all the differential
protection logic settings.
➢ 87L.En_CTS_Blk set as 0
- Use the Quick CMC function of test kit and set local Ir as ramp
signal, step is 0.01A.
- Start the test kit, only inject local Ir0.2A, keep longer than 10S to
make sure the CTS alarm issue.
- Increase the current slowly, when the differential current is higher
than 87L.I_CTS, protection will trip.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ 87L.En_CTS_Blk set as 1
- Use the Quick CMC function of test kit and set local Ir as ramp
signal, step is 0.01A.
- Start the test kit, only inject local Ir0.2A, keep longer than 10S to
make sure the CTS alarm issue.
- Increase the current slowly, when the differential current is higher
than 87L.I_CTS, protection will not trip.
87 Interstrip function Test
- The purpose of this function is to avoid the following circumstance: If there
is an earth fault occurred with a very high resistance on a long-distance line,
the relay cannot pickup if it is far away from the faulty location.
- The logic setting [87L.En_InterTrp] enable or disable the logic for receive
signal of inter trip function, not include the send signal. No matter set it as 0
or 1, the relay will always send the inter trip signal to the remote relay if any
element operates in local side.
- Set 87L.En_InterTrp=1 in local relay, if the inter trip signal from the remote
relay comes, and the common condition of differential protection is satisfied
(Differential current is higher than the pickup setting of 87Land0.15 times of
the restricted current both), the inter trip function will operate with time delay
10ms, the operation report will be 87L.Op_InterTrp.
- Set 87L.En_InterTrp=0, the relay will not operate if the inter trip signal comes.
- Set local 87L.En_InterTrp as 0, remote87L.En_InterTrp as 1. Increase the
pickup setting of the remote relay to avoid the relay operates caused by
differential current.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Set two sequence states, the angle between the two sides is 180° (local side
current is higher than the remote side), make sure the differential current is
higher than the remote side pickup setting and higher than 0.15 times of
restricted current.
- Inject the voltage in local side to simulate distance protection operate, and the
differential protection does not operate. To send the inter trip signal to the remote
side.
- We can find that distance protection operates in local and in the Remote Side
87L.Op_InterTrp Operates also with operating time of 10ms.
➢ Notice:
- Local side faulty current2.2A, remote side 1.1A.
- Differential current is 2.2-1.1=1.1A, it is larger than the pickup
setting.
- [Differential current] / [restricted current] =1.1/3.3=0.33, it is
larger than 0.15, but less than the differential slope 0.6.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Distance Protection (21M/21Q) Test
3.8.1)
Purpose of Test
- When a fault happens on a power system, distance protection will trip
circuit breaker to isolate the fault from power system with its specific
time delay if the fault is within the protected zone of distance
protection.
- For long overhead transmission lines we use distance protection with
different zones with different time for tripping can protect all transmission
line.
- Discriminate tripping and non-tripping zones of its setting.
3.8.2) Work Instructions/Test Procedures :
1- Preparing connection of OMICRON tester.
2- Connect probs of voltage and current to OMICRON tester.
3- Calculate local and remote current carefully to inject them and
make sure relay will work successfully.
➢ Distance protection includes:
1- DPFC distance protection:
• It is independent fast protection providing extremely fast speed to
clear close-Up fault especially on long line and thus improves system
stability.
2- Mho phase-to-phase distance protection
• Zone 1: forward direction
• Zone 2~5: settable forward or reverse directional Neutral current
differential element (1 stage)
3- Mho phase-to-ground distance protection
• Zone 1: forward direction
• Zone 2~5: settable forward or reverse direction.
4- Quadrilateral phase-to-phase distance protection
• Zone 1: forward direction
• Zone 2~5: settable forward or reverse direction
5- Quadrilateral phase-to-ground distance protection
• Zone 1: forward direction
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Zone 2~5: settable forward or reverse direction
6- Pilot distance protection
• The pilot zone is for PUTT, POTT and blocking scheme. The
forward direction element is for sending signal for POTT and
tripping upon receiving permissive signal for both PUTT and
POTT scheme. The forward direction element for blocking scheme
is used to stop sending blocking signal. The reverse direction
element is only for POTT scheme with weak infeed condition.
7- Load encroachment
• It is used to prevent all distance elements from undesired trip due
to load encroachment under heavy load condition especially for
long lines.
8- Out-of-step protection (OOS)
9- Power swing blocking releasing (PSBR)
• For power swing with external fault, distance protection is always
blocked, but for power swing with internal fault, PSBR will
operate to release the blocking for distance protection.
10- SOTF distance protection
• For manual closing or automatic closing on to a fault, zone 2, 3
or 4 of distance protection will accelerate to trip.
Distance Protection (21Q)
- Setting:
➢ Notice:
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- In the setting list, the x in ZGx&ZPx is 1, 2, 3, 4, 5, means stage
1\2\3\4\5 of the 21M/21Q.
➢ Test of phase to ground fault
- According to the phase voltage calculate formula:
- Use the sequence function of test kit and simulate two states:
- State1 simulates the normal condition:
• Set Ur/Us/Ut as positive sequence rated voltage Un.
• Ir/Is/It set as 0.
• This state lasts for 11S (longer than 10S, the drop-off time
setting of VTS alarm).
- State 2 simulates faulty state:
• Faulty voltage set as 39.9V, Faulty current set as 5A.
• When test the reactance setting, the faulty current should lag
the voltage 75° (The angle value of positive sequence angle of
line).
• When test the resistance setting, the angle of faulty current and
faulty voltage is the same.
• State 2 lasts for 0.05S.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Result:
• If AR ready before state 2, distance protection will trip phase R and reclose
successfully.
• If any stage of PG distance protection enables the Block AR logic
setting, distance protection will trip three phase and not reclose.
• Repeat this step for two other phases.
➢ Test of phase-to-phase fault
- According to the phase voltage calculate formula:
- Use the sequence function of test kit and simulate two states:
- State1 simulates the normal condition:
• Set Ur/Us/Ut as positive sequence rated voltage Un.
• Ir/Is/It set as 0.
• This state lasts for 11S (longer than 10S, the drop-off time setting of
VTS alarm).
- State 2 simulates faulty state:
• Faulty voltage set as 23.75V, Faulty current set as 5A.
• When test the reactance setting, the faulty current should lag the
voltage 75°(The angle value of positive sequence angle of line).
• When test the resistance setting, the angle of faulty current and faulty
voltage is the same.
• State 2 lasts for 0.05S.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test of distance protection trip
R-S phase to phase fault: Urs = 23.75V
S-T phase to phase fault: Ust = 23.75V
T-R phase to phase fault: Utr = 23.75V
➢ Result:
If the AR ready before state 2, and the AR mode is 3P AR or 1P/3P AR, the distance
protection will trip three phase and auto reclose, if the AR mode is 1P AR, distance
protection will trip three phase and not reclose.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) Test of distance protection not trip
R-S phase to phase fault: Urs = 26.25V
S-T phase to phase fault: Ust = 26.25V
T-R phase to phase fault: Utr = 26.25V
➢
Result: Fault detector pick up, relay not trip.
➢ Notice:
- Stage 4 is the reverse directional and during testing the angles of
faulty current should plus 180° on the degrees of stage 1\2\3.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- In the above pictures of the test, voltage is marked by the red circles,
please set the voltage angle correctly to make sure the angle of the
voltage of normal phase is continuous.
➢ Quadrilateral forward distance element characteristics:
- Where:
ZZD: impedance setting in forward direction
RZD: resistance setting in forward direction
φ: line positive-sequence characteristic angle
α: the angle of directional line in the second quadrant, set by the
setting [21Q.Ang_Alpha]
β: the angle of directional line in the fourth quadrant, fixed at 15 °
θ: downward offset angle of the reactance line AB
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Quadrilateral Reverse distance element characteristics:
- Zone 2, 3, 4, 5 can be set as reverse direction by the setting [21 x. DirMode]
(x=2, 3, 4, 5). When a fault occurs on the busbar at the back, reverse distance
element is provided to clear it with definite time delay and is used as backup
protection for reverse busbar fault.
- Where:
ZZD: impedance setting in reverse direction
RZD: resistance setting in reverse direction
φ: line positive-sequence characteristic angle
α: the angle of directional line, set by the setting [21Q.Ang_Alpha]
β: the angle of directional line, fixed at 15°
θ: downward offset angle of the reactance line AB.
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Auto test for the boundary of distance protection:
- If the tester has auto test like as OMICRON CMC tester or another
approved tester, we can test distance protection with satisfy each
boundary of zones do not get tripes of each zone only, in addition we
can print out all XRIO file of all zones with tripping and nit tripping
points.
- After opening the function view, click [Test Object Parameters] in
the toolbox to set the distance characteristic.
- Double click [Distance] to open the distance setting view.
-
Page | 306
Set the line impedance and the angle in [System Settings]
Set the distance characteristic in [Zone Settings]
Click [New] 4 times to establish 4 zones of distance protection.
Click on the name of zone1, 2, 3, 4, and set the trip time and
tolerances.
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Double click on zone 1, open the characteristic setting view.
- Assume the impedance of zone 1 is 5Ω, resistance 8Ω, choose Mho
or quadrilateral in [Predefined shapes] to
- set the characteristic of distance protection.
- 21Q (quadrilateral characteristic)
Page | 307
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Notice:
• Tick “Auto close” to get a closed quadrilateral automatically.
• The first line, choose the mode as “Line Cartesian”, set R and X as（0, 0
and the angle as -15˚.
• The second line, choose the mode as “Line Cartesian”, set R and X as（
8, 0）and the angle as 75˚.
• The third line, choose the mode as “Line polar”, set Z and Phi as（5, 75˚
）, and the angle as -12˚.
• The fourth line, choose the mode as “Line cartesian”, set R and X as（0,
0）and the angle as 105˚.
- After setting the characteristic, click OK to go back to the test view.
- Click [Sequence...] to add the test item.
- Set the original point R and X as (0, 0) to set the start point of search
test.
- Set search length, it should cover all the impedance area.
- Set the range of angle, set start angle as 0°and end angle as 90°, angle
step as 30°, then click OK.
- Click [Sequence...] again, set start angle as 0°and end angle as 90°,
angle step as 30°, then click OK. Quadrilateral characteristic
Page | 308
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 309
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Distance Tele-Protection Schemes Test
3.9.1) Permissive Overreaching Transfer Trip (POTT)
- ZPilot will send permissive signal to remote end once it picks up and
release tripping signal upon receiving permissive signal from the remote
end.
3.9.1.1)
Purpose of Test
- Pilot distance protection determines whether it will send the signal to
the remote end according to the discrimination result of the distance
element or direction element. Pilot distance protection can be divided
into permissive scheme and blocking scheme according to whether
the signal sent is used to permit tripping or block tripping. For
permissive scheme, it can be divided into overreaching mode or
underreaching mode according to the setting of distance element and
scheme selected, furthermore, it will provide the unblocking scheme
as auxiliary function. For overreaching mode, current reversal logic
and weak infeed logic are available for parallel line operation and
weak power source situation respectively.
We need to test these functions individually to make sure that all
communication fiber between two relays and each function work
successfully with setting time adapted.
3.9.1.2)
Work Instructions/Test Procedures
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Disable all other functions as follow:
Item
50/51P1.En
50/51G1.En
21SOTF.En
85.Z.En
VTS.En
Page | 310
value
0
0
0
1
0
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Simple schematic of POTT
4- By applying signal receive to slot 09 BI 1 (TB... XB211: 10 &
21) and inject impedance value in zone 2, trip appears on relay
will be tele-prot trip with 0 sec.
5- If the fault is between SS1 & SS2, There is signal transmitted
between protection relays for different feeders
Page | 311
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
6- If the fault is outside SS2, there is no signal transmitted
between protection relays for different feeders.
Permissive Underreaching Transfer Trip (PUTT)
3.10.1) Purpose of Test
- Distance elements zone 1 (Z1) with underreaching setting
and pilot zone (ZPilot) with overreaching setting are used for
this scheme. Z1 element will send permissive signal to the
remote end and release tripping after Z1 time delay expired.
After receiving permissive signal with ZPilot element pickup,
a tripping signal will be released.
3.10.2) Work Instruction/Test Procedures
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Disable all other functions as follow:
Item
50/51P1.En
50/51G1.En
21SOTF.En
85.Z.En
VTS.En
Page | 312
value
0
0
0
1
0
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Simple schematic of PUTT
4- By applying signal receive to BI of relay and inject impedance value in
zone 1, trip appears on relay will be tele-prot. trip with 0 sec.
5- If the fault is between SS1 & SS2, there is signal transmitted between
protection relays for different feeders
Page | 313
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Blocking Transfer Trip
3.11.1)
Purpose of Test
- Permissive scheme has high security, but it relies on pilot channel
seriously. Pilot distance protection will not operate when there is an
internal fault with abnormal channel. Blocking scheme could be
considered as an alternative.
- Blocking scheme takes use of pilot distance element Zpilot operation
to terminate sending of blocking signal. Blocking signal will be sent
once fault detector picks up without pilot zone Zpilot operation. Pilot
distance protection will operate with a short time delay if pilot
distance element operates and not receiving blocking signal after
timer expired.
3.11.2)
Work Instructions/Test Procedures
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Disable all other functions as follow:
Item
50/51P1.En
50/51G1.En
21SOTF.En
85.Z.En
VTS.En
value
0
0
0
1
0
4- Simulation of Blocking scheme from the injected secondary
impedance zone 4(reverse zone) value to the relay
Page | 314
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
5- Inject secondaries values for voltage and current for Z1
➢ Simple schematic of Blocking Scheme
Page | 315
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Switch onto fault protection (21SOTF/50PSOTF)
- Setting List:
Switch onto fault protection (21SOTF) By Manual Close BI:
3.13.1) Purpose of Test
- When the circuit breaker is closed manually or
automatically, it is possible to switch on to an existing fault.
This is especially critical if the line in the remote station is
grounded since time-delayed protection would not clear the
fault until their time delays had elapsed. In this situation,
however, the fastest possible clearance is desired.
3.13.2) Work Instructions/Test Procedures:
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Set the logic setting SOTF.Opt_Mode_ManCls as Man_Cls_BI
4- Connect the BO of the test kit to the Manual close BI of relay.
5- Preparation:
Item
50/51P1.En
50/51G1.En
21SOTF.En
85.Z.En
VTS.En
Page | 316
value
0
0
1
0
0
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
6- Set three states in the sequence test function:
- State 1: Normal condition, Set Ur/Us/Ut as positive rated
voltage Un, set three phase current as 0, this state lasts for 11S.
- State 2: Set the voltage and current same as state1 and output
the BO of test kit to simulate the manual close command to
relay, state lasts for 30ms.
- State 3: Faulty state set the fault in Zone 2, Zone 3or Zone 4
area according to setting. The state lasts for 50ms.
7- Result: 21SOTF operated, time delay 25ms.
Switch onto fault protection (21SOTF) By Breaker Position BI:
3.14.1) Purpose of Test
- When the circuit breaker is closed manually or automatically, it is
possible to switch on to an existing fault. This is especially
critical if the line in the remote station is grounded since timedelayed protection would not clear the fault until their time
delays had elapsed. In this situation, however, the fastest possible
clearance is desired.
3.14.2) Work Instructions/Test Procedures :
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Set SOTF.Opt_Mode_ManCls as CB Pos.
4- Preparation:
Page | 317
Item
value
50/51P1.En
50/51G1.En
21SOTF.En
0
0
1
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
85.Z.En
VTS.En
0
0
5- Connect the BO of the test kit to the Breaker Position BI of relay.
6- Set two states in the sequence test function:
- State 1: Normal condition, Set Ur/Us/Ut as positive rated voltage
Un, three phase current as 0, this state lasts for 11S (longer than
10S) and CB is closed position.
- State 2: Fault condition, set the fault in Zone 2, Zone 3 or Zone 4
area according to setting, state lasts for 50ms.
➢ Result: 21SOTF operated, time delay 25ms.
Page | 318
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Switch onto fault protection (50PSOTF) By Breaker Position BI:
3.15.1) Purpose of Test
- When the circuit breaker is closed manually or automatically, it is
possible to switch on to an existing fault. This is especially
critical if the line in the remote station is grounded since timedelayed protection would not clear the fault until their time
delays had elapsed. In this situation, however, the fastest possible
clearance is desired.
3.15.2) Work Instructions/Test Procedures :
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Set SOTF.Opt_Mode_ManCls as CB Pos.
4- Preparation:
Item
50/51P1.En
50/51G1.En
21SOTF.En
85.Z.En
VTS.En
value
1
0
0
0
0
5- Connect the BO of the test kit to the Breaker Position BI of relay.
6- Set two states in the sequence test function:
- State 1: Normal condition, Set Ur/Us/Ut as positive rated voltage
Un, three phase current as 0, this state lasts for 11S.
- State 2: Faulty state, the over current is higher than
50PSOTF.I_Set, lasts for 50ms.
➢ Result: 50PSOTF operated, time delay 25ms.
Page | 319
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ For 50PSOTF By Manual close BI is the same sequence by change BO of
the Kit by BI of protection Relay.
Reverse Power (32R) Protection Test
3.16.1) Purpose of Test
- Due to various reasons lead to lose motivity, synchronous generator
is changed to run as a motor state, absorbing energy from the power
grid to drive a turbine (gas turbine) operation. To prevent turbine
blade or gas turbine gear from being damaged, reverse power
protection (reversal direction) should be configured.
3.16.2) Work Instructions/Test Procedures :
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Simulate two states:
- State 1 simulate normal state:
• Set Ur/Us/Ut as positive sequence rated voltage Un, Ur angle =0.
• Set Ir/Is/It positive sequence current 1A, the angle between the
voltage and current each phase is 0°~90°.
• This state lasts for 11S (longer than 10S)
- State 2 simulate faulty state:
• Keeps voltage not changing in this state.
• According to the settings, P=20W, so the faulty current should
be 20/63.51/3=0.105A, Set the Ir/Is/It=1.05×0.105A=0.11A,
The angle between voltage and current each phase is 180 °,
lasts for32R1.t_Trp+50ms.
Page | 320
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Setting:
➢ Result:
- If state2 current set as 1.05 times of setting, relay will trip, set as 0.95 time of
setting, Relay not trip.
Page | 321
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Auto Reclose (79) and Synch Check Protection Test
3.17.1) Purpose of Test
- To maintain the integrity of the overall electrical transmission
system, the device is installed on the transmission system to
isolate faulted segments during system disturbances. Faults
caused by lightning, wind, or tree branches could be transient in
nature and may disappear once the circuit is de-energized.
According to statistics, for overhead transmission line,80%~90%
of the faults on overhead lines are the transient faults. Autoreclosing systems are installed to restore the faulted section of the
transmission system once the fault is extinguished (providing it is
a transient fault).
- When external auto-reclosure is used, the device can output some
configurable output to initiate external AR, such as, contact of initiating
AR, phase-segregated tripping contact, single-phase tripping contact,
three-phase tripping contact and contact of blocking AR. According to
requirement, these contacts can be selectively connected to external autoreclosure device to initiate AR.
- For certain transmission systems, auto-reclosure is used to improve
system stability by restoring critical transmission paths as soon as
possible.
➢ Note: this function is used for distance or over current
protection function
3.17.2)
Work Instructions/Test Procedures :
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Disable other zones of distance protection except zone 1.
4- Jumper at test plug points at output contact of Auto reclose.
5- Disable other backup functions.
6- Enable AR function.
7- Close the Circuit Breaker
Page | 322
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
8- Inject voltage and current (impedance value of Z1) into 3 stages
as follow:
• State1: Healthy state for time more than CB in Service Time
(more than 3S)
• State 2: Trip Z1
• State 3: CB Re-Closing state with time more than Dead Time
(more than 0.5S) CB Status is simulated.
➢ AR TEST with Live Line Live Bus sync. condition
➢ AR TEST with Live Line Dead Bus sync. condition
Page | 323
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ AR TEST with Deadline Live Bus sync. condition
➢ AR TEST with Deadline Dead Bus sync. condition
➢ DEAD TIME Measurement:
• Program two Binary Output from the relay to operate when injection of an
instantaneous fault takes place (Trip contact) and connect one to Start the
Timer and the other one to BI of the Freja to stop the injection.
• Program another Binary Output to operate when the dead time elapses (Closing
Pulse Contact) and connect it to Stop the Timer.
• Measure the Dead Time of the AR relay,
• Record the Dead Time and calculate the percentage error by the formula:
error% = Set Time / Dead Time
• Repeat the test at different settings of dead time.
Page | 324
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ RECLAIM TIME Measurement:
• After the Dead Time has elapsed and all conditions of closing the circuit
breaker are fulfilled, a closing pulse will be sent from the AR relay to the
circuit breaker. Assign a BO from the AR to Start the Timer
• Enable the function of AR second shot if its disabled.
• Record the Reclaim Time and calculate the percentage error by the
formula: error% = Set Time / Reclaim Time.
➢ Single-phase transient fault
Page | 325
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 326
➢
Single-phase permanent fault
➢
AR Setting Values
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 327
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Synch Check Test
1- Live Line - Live Bus Sync. Check
- SYNCHRO-CHECK VOLTAGE CHECK:
- Fix U1 at normal voltage and change U2.
MEASURED VOLTAGE U2
SETVALUE
APPLIED
PICK-UP
U % (V)
VOLTAGE U1
Voltage (V)
Errors %
+U
10.0
+U
-U
-U
+U %
+U %
57.74
- Fix U2 at normal voltage and change U1.
MEASURED VOLTAGE U1
SETVALUE
APPLIED
PICK-UP
U % (V)
VOLTAGE U2
Voltage (V)
Errors %
+U
10.0
+U
-U
-U
+U %
+U %
57.74
- SYNCHRO-CHECK FREQUENCY CHECK:
- Fix U1 at normal frequency and change frequency of U2.
f
PICK-UP
f (U2)
+f
-f
+f
-f
100mHz
- Fix U2 at normal frequency and change frequency of U1.
+f
100mHz
Page | 328
f
PICK-UP
f (U1)
-f
+f
-f
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- SYNCHRO-CHECK PHASE ANGLE CHECK:
- Fix U1at zero reference phase angle and change phase angle of U2.
ANGLE DIFFERENCE (U2)
SET
VALUE
+ Angle
- Angle
+ Angle
Errors %
- Angle
+ Angle
- Angle
15
- Fix U2 at zero reference phase angle and change phase angle of U1.
ANGLE DIFFERENCE (U1)
SET
VALUE
+ Angle
- Angle
+ Angle
Errors %
- Angle
+ Angle
- Angle
15
2- Live Line - Dead Bus Sync. Check
- Set the live value = 80 % of nominal voltage & Dead Value = 5 % of
nominal voltage.
Pickup value of U1
Live
Error % of U1
Pickup value of U2 Dead
Error % of U2
3- Deadline - Live Bus Sync. Check
- Set the live value = 80 % of nominal voltage & Dead Value = 5 % of
nominal voltage
Pickup value of U1
Dead
Error % of U1
Pickup value of U2
Live
Error % of U2
4- Deadline - Dead Bus Sync. Check
- Set the live value = 80 % of nominal voltage & Dead Value = 5 % of
nominal voltage
Pickup value of U1
Dead
Page | 329
Error % of U1
Pickup value of U2
Dead
Error % of U2
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Over Voltage and Under Voltage Protection Functions(59P/27P) Test
3.16.1) Purpose of Test
- Abnormal high voltages often occur e.g. in low loaded, long distance
transmission lines, in islanded systems when generator voltage
regulation fails, or load rejection of a generator. Even if
compensation reactors are provided to avoid line overvoltage by
compensation of the line capacitance and thus reduction of the
overvoltage, the overvoltage will endanger the insulation if the
reactors fail. The line must be de-energized within a very short time.
- The overvoltage protection in this device detects the phase voltages
Ua, Ub and Uc or the phase-to-phase voltages Uab, Ubc and Uca
with an option of any phase or all phases operation for output. The
overvoltage protection can be used for tripping purpose as well as to
initiate transfer trip, which selectable controlled by local circuit
breaker.
3.16.2) Work Instructions/Test Procedures :
1- Preparing connection of Freja 300 tester.
2- Connect probs of voltage to Freja 300 tester.
3- Check the relay’s configuration, disturbance recorder, contact
resistance of all relay outputs and the operation of binary inputs
and outputs on the relay’s LCD display.
4- Configure LED’s as per required functions.
5- Perform Voltage measurement test by applying the correct VT ratio
to the relay and checking both the primary and secondary
measurements.
6- For Over Voltage Protection Function:
• Measure and record the relay’s Pick-up voltage for L1 to
L2(Phase R), L2 to L3(Phase Y), L3 to L1(Phase B), by applying
secondary voltage values as per PED’s Overvoltage Setting until
such time the pick-up voltage is reached.
• Measure and record the relay’s drop-off voltage for L1 to
L2(Phase R), L2 to L3(Phase Y), L3 to L1(Phase B), by applying
secondary voltage values as per PED’s Overvoltage Setting until
such time the drop-off voltage is reached.
Page | 330
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Calculate the Reset Ratio with the formula:
7- For Over Voltage Protection Function:
• Measure and record the relay’s Pick-up voltage for L1 to
L2(Phase R), L2 to L3(Phase Y), L3 to L1(Phase B), by applying
secondary voltage values as per PED’s Undervoltage Setting
until such time the pick-up voltage is reached.
• Measure and record the relay’s drop-off voltage for L1 to
L2(Phase R), L2 to L3(Phase Y), L3 to L1(Phase B), by applying
secondary voltage values as per PED’s Undervoltage Setting
until such time the drop-off voltage is reached.
• Calculate the Reset Ratio with the formula:
Broken Conductor (46BC) Protection Function
3.17.1) Purpose of Test
- Broken-conductor fault mainly is single-phase broken, or two-phases
broken. According to the ratio of negative-sequence current to positivesequence current (I2/I1), it is used to judge whether there is a brokenconductor fault. Negative-sequence current under normal operating
condition (i.e., unbalance current) is due to CT error and unbalance load,
so the ratio of negative-sequence current to positive-sequence current
(amplitude) is relative steady. The value with margin can then be used as
the setting of broken conductor protection. It is mainly used to detect
broken-conductor fault and CT circuit failure as well.
3.17.2) Work Instructions/Test Procedures :
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Set 2 states:
- State 1 is normal condition:
• Set Ur/Us/Ut as positive sequence rated voltage Un.
• Set Ir/Is/It as 0.
• State lasts for 11S (longer than 10S)
Page | 331
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- State 2 is fault condition:
• Keep Ur/Us/Ut as rated value.
• Setting:
• Set Is=2A∠-120°, It=2A∠120°, Ir=0.196A∠180°,
• According to following equations:
𝐼2/𝐼1= [(2+0.1963)/3]/[ (4−0.1963)/3] = 0.577 Lasts for
46BC.t_Op+50ms.
➢ Result:
In state 2, if I2/I1is higher than setting, relay will trip.
Page | 332
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Thermal Overload (49)
3.18.1) Purpose of Test
- During overload operation of a transmission line (specially for cable),
great current results in greater heat to lead temperature increase and if
the temperature reaches too high values the equipment might be
damaged.
- Thermal overload protection estimates the internal heat content
(temperature) continuously. This estimation is made by using a
thermal model with two-time constants, which is based on current
measurement.
- When the temperature increases to the alarm value, the protection
issues alarm signals to remind the operator for attention, and if the
temperature continues to increase to the trip value, the protection
sends trip command to disconnect the protected line.
- Thermal overload protection has following functions:
• Thermal time characteristic Adopting IEC 60255-8
• Two stages for alarm purpose and two stages for trip purpose
• Thermal accumulation can be cleared by external input signal
• The device provides a thermal overload model which is based
on the IEC60255-8 standard. The thermal overload formulas
are shown as below.
3.18.2) Work Instructions/Test Procedures :
1- Preparing connection of OMICRON tester.
2- Connect probs of current and voltage to OMICRON tester.
3- Connect BO of protection relay kit with BI of tester kit.
4- Step1: Set Ur/Us/Ut as the positive sequence rated voltage Un, and Ir/Is/It
as0, then start the test kit.
5- Step2: Click the hold values button on the test view or press F9 to
continue the analog outputs of the test kit.
6- Step3: Change the current and voltage to simulate a single-phase
fault, then release the analog outputs of the test kit.
7- Test the operating time by injecting different faulty current.
Page | 333
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ Characteristic’s:
❖ Setting:
❖ Pickup values:
Page | 334
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Power Swing Releasing Block Protection Function Test
3.19.1) Purpose of Test
- When power swing occurs on the power system, the impedance measured
by the distance measuring element may vary from the load impedance area
into the operating zone of the distance element. The distance measuring
element may operate due to the power swing occurs in many points of
interconnected power systems. To keep the stability of whole power
system, tripping due to operation of the distance measuring element during
a power swing is generally not allowed. Our distance protection adopts
power swing blocking releasing to avoid maloperation resulting from
power swing. In another word, distance protection is blocked all along
under the normal condition and power swing when the respective logic
settings are enabled. Only when fault (Internal fault or power swing with
internal fault) is detected, power swing blocking for distance protection is
released by PSBR element.
- In the Power Swing case, the Impedance will decrease but in very short
time, it will be decrease related with proper time for that decreasing, so the
Power Swing depend on changing the Impedance with Time (dZ / dt).
However, the time must be proper with this changing (Not very short when
the Impedance will decrease).
- As shown in figure below, if normal load impedance locates at position 1
and the impedance locates at position 2 when positive-sequence current is
lower than the setting [I_PSBR], it means FD operates between point 1 and
point 2 if operation condition for FD PSBR mentioned above is fulfilled
(point 3 as an example), and then FD PSBR will operate for 160ms.
Page | 335
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.19.2) Work Instructions/Test Procedures :
1- Preparing connection of Freja 300 tester.
2- Connect probs of current and voltage to Freja 300 tester.
3- Inject Normal Current & Normal Voltage, Then Decrease the Voltage by
constant (d / dt),
[ (i.e.) Decrease the Impedance by (dZ / dt).]
4- The Power Swing depend on changing the Impedance with Time (dZ/dt)
5- The Power Swing Impedance starts before Z5 by 5Ω
6- When the Impedance enter the Polygon the relay trip by Delay after
Power Swing Blocking.
7- If the changing of the Impedance in the Polygon is slowly then the
relay will be Blocked by The Power Swing Function.
8- If the changing of the Impedance in the Polygon is fastly and the Impedance is
gone out from the Polygon, then any Fault will make Trip.
Page | 336
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
VTS (Voltage Supervision) Protection Function
3.20.1) Purpose of Test
- The VT supervision function monitors the healthiness of Potential transformers and
gives alarm in case of PT fails to measure voltage. It is rare to fail PTs themselves,
the common problem is with failure of protective fuses connected in series with
PTS.
- VTS function is very important for alarm signals when one or 2phases fail and
blocking signal for distance function or another function depending on voltage.
3.20.2) Work Instructions/Test Procedures :
1- Preparing connection of Freja 300 tester.
2- Connect probs of current and voltage to Freja 300 tester.
3- Setting:
- VTS time delay
= 5.0 Sec.
- VTS I2> and Io> inhibit = 500 mA
- Delta I> block
=0.1 A
- Threshold for 3p detect
= 30 V
Loss of one or two phases test:
-
Fixed setting = 75% VN (Ures=3Uo = 0.75 * Uph)
Apply 3 Phase rated voltage (Ur V) with balanced angles.
Apply 3 Phase rated current (Ir A) with balanced angles.
For the phase under test start decrease the voltage on one phase and / or
two phases till you get Internal fuse fail (fuse fail without time lag).
- For time test inject voltage less than Vo.
Page | 337
Inspection Test Plan
ITP Guidebook
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being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
PHASE
UNDER
TEST
Fixed setting
(Uo=1/3
Ures) volts
Measured
value
(Vo) volts
Set
Time
(sec)
Measured
Time
(sec)
R
Y
5.0
Sec.
14.43 V
B
CHECK THE FUSE FAIL UNBLOCKING BY I2> and Io>
-
Simulate 3 phase voltage to get fuse Fail.
Io = 1/3 (IA + IB + IC), Where IA, IB, IC is vectors component
I2 = 1/3 (IA + a2 * IB + a * IC), where a = 1 L120, a2 = 1 L240
For VTS Unblock by Io> inject the rated current on two phases and increase the
third phase current from rated current till you get fuse fail removed.
- For VTS Unblock by I2> inject 3ph balanced and but with swap phase Y
with phase B angle (ph. Y angle = 120, ph. B angle = 240)
With 1.0 A rated & decrease 3 phase current till you get fuse fail.
- [I2> Unblock measured >
mA].
- [Io> Unblock measured>
mA].
Check the relay unblocking trip during internal fuse fail for Io & I
- Simulate 2 stages:
- Stage 1: inject 3 phase voltage to get fuse fail and zero current.
- Stage 2: inject the same voltage as in stage 1 & inject 3 phase current to get a
value greater than Io> inhibit.
Testing of 3 phase voltages loss (detect 3p)
- Setting range = 10 to 70 volts.
Set volts (V)
Applied current per
phase(A)
30.0 V
1.0
Measured volts
(V)
- Apply 3 Phase Voltage as healthy condition.
- Decrease the 3 phase Voltage until VTS Operate
Page | 338
Inspection Test Plan
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
DELTA I> Test
- Stage 1: normal case (V=Vr & I=Ir) for the three phase.
- Stage 2: test case (V<U/V on 3phase & current >or≤ ΔI setting) for fuse fail
block or fuse fail unblock.
ΔI Measured=
A.
- Note: check of ΔI setting should be during one cycle so, use sequence test method.
Absence of 3 phase volts online Energization test
- VT MCB input energized (VT MCB OFF), apply 3 phase 1A current with no volts
Apply Fault – Relay Not Trip
- VT MCB input not energized (VT MCB ON), apply 3 phase 1A current with no volts
Apply Fault – Relay Trip
Fault Locator Protection Function (FL)
3.26.1) Purpose of Test
- The fault locator function is used for recording an estimated distance to
the point where a fault has occurred. It is mostly used in directional
overcurrent protection or distance protection applications but can be
also triggered by other protections. The function can be used if all
three phase currents and three phase voltages are available.
3.26.2) Work Instructions/Test Procedures :
1- Preparing connection of Freja 300 tester.
2- Connect probs of current and voltage to Freja 300 tester.
3- Setting:
• Reactance set at =
Ω/ Km
• Length =
Km
• Calculated total reactance of line =
Ω
4- Apply 3 phase voltage and current to generate zero sequence voltage and
current equal to reactance impedance of the line for example at 30% of line:
5- Voltage V1= 6.83∟90 V2= 66.4∟330, V3= 66.4∟210,
Current 1=1.12∟0, I2= 1.0∟240, I3=1.0∟120
6- Compensation in test set shall be set to zero for earth faults.
7- Results for Distance Relay:
Page | 339
Inspection Test Plan
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being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Item
Fault Type
Distance to Fault
Relay Fault Location
Km
Expected
Remarks
Actual
1
R-N
25% Line Length
1.3
-
2
B-N
25% Line Length
1.3
-
3
Y-B
25% Line Length
1.3
-
4
Y-N
50% Line Length
2.55
-
5
R-Y
50% Line Length
2.55
-
6
R-Y
75% Line Length
3.83
-
7
R-B
75% Line Length
3.83
-
8
Y-B
100% Line
Length
5.1
9
R-Y-B
100% Line
Length
5.1
10
R-N
Reverse
25% Line Length
-0.29
11
Y-B
Reverse
25% Line Length
-0.29
12
R-B
Reverse
50% Line Length
-0.59
13
R-Y-B
Reverse
50% Line Length
-0.59
14
R-Y
Reverse
100% Line
Length
-1.17
Page | 340
-
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
PCS-978 Power Transformer Relay
Functions Procedure Test
Page | 341
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being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Protection Relay Technical Data (Name Plate)
- We select power Transformer YNd11 as example for all tests are
mentioned below.
Designation No.
PCS-978
CT rating
Manufacturer
Type
S/N
NR
Differential relay
NRJB2134802170010
VT rating
Rated frequency
Aux. Voltage
300/1 A (HVS)
750/1 A (LVS)
220/0.1 KV
50 HZ
110
dc
2) Test Equipment’s Used:
Note: Used tester types below or approved testers
S.N
Type
Make
1
Freja 300
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Software will be used for configuration and final setting tests
- We will use the PCS-Explorer V1.1.2 in this instruction.
Page | 342
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
3.1) Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that protection relay is good for testing, and it doesn’t
have any damage or missing parts.
ITEM
DESCRIPTION
CHECKED
1
Inspect for any physical damage or defects.
2
Verify connections as per approved drawings.
3
Check that serial no. of relay matching with serial no. of display.
3.2) Electrical Tests:
3.2.1) Functional Test
ITEM
DESCRIPTION
CHECKED
Set Clock to local time
1
Date & time
2
4
Make Test Mode Enable under commissioning menu to check ALARM LED
Make Test Mode Enable under commissioning menu to check OUT OF SERVICE
LED
Apply any fault condition to check TRIP LED (Red)
5
Apply Test LEDs under commissioning menu to check all programmable LEDs.
6
Measured FIELD SUPPLY Voltage
-
3.2.2) Measurement Test:
Inject values for current to make sure ratio is ok
3
Side
Time maintained when Aux. Supply removed
Input CT
Between terminals (+ve) – (-ve)
Applied value
Displayed value
IA
1A
299.628
IB
1A
300.744
IC
1A
299.628
IA
1A
750.0
IB
1A
749.07
IC
1A
749.06
1A
300.178
220 KV
20 KV
220 KV NP
Page | 343
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
-
Inject values for Voltage to make sure ratio is ok
Side
Input CT
Applied value
Displayed value
(KV)
VA
57.73 V
127.5
VB
57.73 V
127.4
VC
57.73 V
127.04
Input CT
Applied value
Displayed value
(KV)
VA
57.73 V
11.54
VB
57.73 V
11.54
VC
57.73 V
11.54
220 KV
Side
20 KV
Page | 344
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Transformer Differential Protection (87T) Test
3.3.1) Purpose of Test
In power system, the power transformer is one of most valuable and
expensive equipment. If a fault occurs in the protection zone of a
transformer, current differential protection operates quickly to clear the
fault to avoid the transformer from damages or reduce the maintenance
cost as low as possible.
We test differential protection curve for selected points and make sure
that points with slope less than setting slope, the relay not trip
3.3.2) Work Instructions/Test Procedures :
1- Preparing connection of FREJA tester.
2- Connect probs of current to Freja tester with one channel.
3- Prepare calculations of differential function.
➢ Pickup Differential Test:
❖ Setting:
Global:system_settings
Group1:diff_prot_settings
Page | 345
Name
Sn
HVS.U1n_Plate
LVS.U1n_Plate
Clk_LVS_WRT_HVS
Clk_PhComp
HVS.En_I0Elim
LVS.En_I0Elim
HVS.I1n
HVS.I2n
LVS.I1n
LVS.I2n
87T.I_Knee1
87T.I_Knee2
87T.I_Biased
87T.I_Inst
87T.Slope1
87T.Slope2
87T.Slope3
87T.I_Alm
87T.En_Inst
87T.En_Biased
87T.En_DPFC
87T.En_CTS_Blk
Value
12.5
220
20
11
11
1
0
300
1
750
1
0.6
5
0.4
13
0.2
0.5
0.75
0.25
1
1
0
1
Unit
MVA
KV
KV
clk
clk
--A
A
A
A
PU
PU
PU
PU
---PU
-----
Inspection Test Plan
ITP Guidebook
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being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ Preparation:
Group1:HVS_REF_prot_settings
Group1:HVS_backup_prot_settings
Group1:LVS_backup_prot_settings
Group1:diff_prot_settings
-
Page | 346
Name
HVS.64REF.En
HVS.50/51Px.En
HVS.50/51Gx.En
LVS.50/51Px.En
87T.En_CTS_Blk
Value
0
0
0
0
0
❖ Calculations:
We will test pick up values of differential current by using
connection below for HVS and LVS individually
Unit
-----
Inspection Test Plan
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Calculated diff. pickup values according to the following eq.:
I injected = Ipickup *Irated * CTR * KVG
Where:
12.5∗1000
I rated HVS = *
1.732∗220
I rated LVS = *
12.5∗1000
1.732∗20
= 32.8 A
= 360.8 A
According to vector group (YNd11) from relay manual, we will use this
compensation matrix and we use vector group factor KVG for easily
calculations.
KVG=1/compensation matrix, so we will use KVG as follow:
Fault type
1 ɸ (with Zero seq. elimination)
1 ɸ (without Zero seq. elimination)
2ɸ
3ɸ
LVS (Delta)
1.5
1
1
1
𝑦1
To get the min. differential current 𝑥1 = 2 = 𝑠𝑙𝑜𝑝𝑒
𝑦1−0.4
𝑥1
= 0.2
X1 = 0.222
Page | 347
HVS ( Y )
1.73
1.73
0.866
1
y1 = 2x1
2x1-0.4 = 0.2X1
y 1 = 0.444 = min. diff. pickup
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
HVS calculations:
1 phase with zero seq. elimination = 0.444 * 32.8 *
1
2 phase = 0.444 * 32.8 *
3 phase = 0.444 * 32.8 *
300
1
3 phase = 0.444 * 360.8 *
300
* 1.73 = 0.084 A
* 0.866 = 0.042 A
300
* 1 = 0.049 A
LVS calculations:
1 phase w/o zero seq. elimination = 0.444 * 360.8 *
2 phase = 0.444 * 360.8 *
1
1
750
1
*1=
0.2136 A
*1=
0.2136 A
750
1
750
*1=
0.2136 A
Testing Values:Faulted
phase
R
S
T
RS
ST
TR
RST
Page | 348
pickup
0.086
0.084
0.084
0.043
0.043
0.044
0.049
HVS
Timing (ms)
25.6
26.1
26.5
26.9
26.3
26.3
26.3
pickup
0.214
0.215
0.214
0.213
0.214
0.213
0.214
LVS
Timing(ms)
25.6
26.5
26.6
26.3
26.1
26.2
26.0
Inspection Test Plan
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Differential characteristics:
❖ Setting Preparations:
As shown before in differential pickup test.
❖ Operation characteristic of sensitive biased differential element
is shown below
Page | 349
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being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ c/c’s calculations for vector group YnD11we have the
following o’clock so , if we inject 1 phase fault at HVS we
must inject 2 phase fault at LVS.
❖ So we use 1 phase KVG value for HVS (1.73) and 2 phase KVG value
for LVS(1)
❖ HVS Factor=PU*32.8*1/300*1.73=0.189PU
❖ LVS Factor=PU*360.8*1/750*1=0.481PU
HVS
LVS
RN
RT
SN
SR
TN
TS
➢ Point (2)
Let X2 = 0.4
𝑦2−0.4
0.4−0
y2 – 0.4 = 0.08
= 0.2
Y2 = 0.48
Id = 0.48 = I1 – I2
Ir = 0.4 =
𝐼 1+𝐼2
2
(1)
0.8 = I1 + I2
(2)
By solving (1) & (2) equations, we get I1 = 0.64 PU & I2 = 0.16 PU
I1 injected = 0.64 * 0.189 = 0.121 A
I2 injected = 0.16 * 0.481 = 0.077 A
➢ Point (3)
Let X3 = 0.6
𝑦3−0.4
0.6−0
= 0.2
y3 = 0.52
𝐼𝑑 = 0.52 = I1 – I2
𝐼 𝑟 = 0.6 =
𝐼 1+𝐼2
2
(1)
(2)
By solving (1) & (2) equations , we get I1 = 0.86 PU & I2 = 0.34 PU
I1 injected = 0.86 * 0.189 = 0.162 A
I2 injected = 0.34 * 0.481 = 0.1635 A
Page | 350
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being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Point (4)
Let X4 = 1
𝑦4−0.52
= 0.5
y4 = 0.72
𝐼𝑑 = 0.72 = I1 – I2
(1)
1−0.6
𝐼𝑟 =1 =
𝐼 1+𝐼2
2
(2)
By solving (1) & (2) equations , we get I1 = 1.36 PU & I2 = 0.64 PU
I1 injected = 1.36 * 0.189 = 0.257 A
I2 injected = 0.64 * 0.481 = 0.308 A
➢ Point (5)
Let X5 = 3
𝑦5−0.52
= 0.5
y5 = 1.72
𝐼𝑑 = 1.72 = I1 – I2
(1)
3−0.6
𝐼𝑟 =3 =
𝐼 1+𝐼2
2
(2)
By solving (1) & (2) equations , we get I1 = 3.86 PU & I2 = 2.14 PU
I1 injected = 3.86 * 0.189 = 0.729 A
I2 injected = 2.14 * 0.481 = 1.029 A
➢ Point (6)
Let X6 = 5
𝑦6−0.52
= 0.5
y6 = 2.72
𝐼𝑑 = 2.72 = I1 – I2
(1)
5−0.6
𝐼𝑟= 5 =
𝐼 1+𝐼2
2
(2)
By solving (1) & (2) equations , we get I1 = 6.36 PU & I2 = 3.64 PU
I1 injected = 6.36 * 0.189 = 1.202 A
I2 injected = 3.64 * 0.481 = 1.750 A
Page | 351
Inspection Test Plan
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Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Point (7)
Let X7 = 8
𝑦7−2.72
= 0.75
y7 = 4.97
𝐼𝑑 = 4.97 = I1 – I2
(1)
8−5
𝐼𝑟 =8=
𝐼 1+𝐼2
2
(2)
By solving (1) & (2) equations, we get I1 = 10.485 PU & I2 = 5.515 PU
I1 injected = 10.485 * 0.189 = 1.981 A
I2 injected = 5.515* 0.481 = 2.653 A
➢ Point (8)
Let X8 = 10
𝑦8−2.72
= 0.75
y8 = 6.47
𝐼𝑑 = 6.47 = I1 – I2
(1)
10−5
𝐼 𝑟 = 10 =
𝐼 1+𝐼2
2
(2)
By solving (1) & (2) equations, we get I1 = 13.235 PU & I2 = 6.765 PU
I1 injected = 13.235 * 0.189 = 2.501 A
I2 injected = 6.765* 0.481 = 3.254 A
Page | 352
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ Testing Values:
c/c’s
point
2
3
4
5
6
7
8
HVS phase R
magnitude
Angle
0.121
0
0.163
0
0.257
0
0.728
0
1.199
0
1.978
0
2.496
0
LVS phase R
magnitude
angle
0.0765
0
0.163
0
0.307
0
1.029
0
1.751
0
2.653
0
3.255
0
LVS phase T
magnitude
angle
0.0765
180
0.163
180
0.307
180
1.029
180
1.751
180
2.653
180
3.255
180
c/c’s
point
2
3
4
5
6
7
8
HVS phase S
magnitude
Angle
0.120
0
0.162
0
0.255
0
0.726
0
1.196
0
1.973
0
2.492
0
LVS phase S
magnitude
magnitude
0.0765
0
0.163
0
0.307
0
1.029
0
1.751
0
2.653
0
3.255
0
LVS phase R
magnitude
angle
0.0765
180
0.163
180
0.307
180
1.029
180
1.751
180
2.653
180
3.255
180
c/c’s
point
2
3
4
5
6
7
8
HVS phase T
magnitude
Angle
0.121
0
0.162
0
0.255
0
0.727
0
1.197
0
1.974
0
2.493
0
LVS phase T
magnitude
angle
0.0765
0
0.163
0
0.307
0
1.029
0
1.751
0
2.653
0
3.255
0
LVS phase S
magnitude
angle
0.0765
180
0.163
180
0.307
180
1.029
180
1.751
180
2.653
180
3.255
180
Page | 353
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Inrush Current 2nd Harmonics Blocking Test
3.4.1) Purpose of Test
- The “Inrush current and 2nd harmonic detection” function
recognizes an inrush process on transformers, generates a blocking
signal for protection functions that protect the transformer
(protected object) or for protection functions that are affected in
undesirable ways when transformers are switched on, and allows a
sensitive setting of the protection functions.
- We make sure that 2nd , 3rd and 5th harmonics frequencies don’t
effect on differential protection by wrong so we block this
harmonics during connecting transformer.
3.4.2) Work Instructions/Test Procedures:
1- Setting:
Group1:diff_prot_settings
Name
87T.En_Inst
87T.En_Biased
87T.K_Hm2_Inrush
87T.Opt_Inrush_Ident
87T.Opt_BlkMode_Inrush
Value
1
1
0.2
1
1
Unit
----
Value
0
0
0
0
0
Unit
------
--
2- Preparation:
Group1:HVS_REF_prot_settings
Group1:HVS_backup_prot_settings
Group1:LVS_backup_prot_settings
Name
LVS.64REF.En
HVS.50/51Px.En
HVS.50/51Gx.En
LVS.50/51Px.En
LVS.50/51Gx.En
3- Connect I prim L1 & L2 from Freja with the same phase @ relay.
4- Make frequency of I prim L2 equals 100 HZ with magnitude equals 0.21
5- -Gradually decrease value of I prim until the pickup value of 2nd
harmonic
Page | 354
Phase
Fundamental
R
S
T
1A
1A
1A
2nd harmonic (100 HZ)
pickup
0.2
0.2
0.2
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Inrush Current 3rd and 5th Harmonics Blocking Test
3.5.1) Purpose of Test
- When a transformer is overexcited, the exciting current will increase
sharply which may result in an unwanted operation of differential
protection. Therefore, the overexcitation shall be discriminated to block
differential protection. The third or fifth harmonic differential current can
be selected to determinate overexcitation.
- If overexcitation factor is less than 1.4, biased differential element is
blocked when the constant of fifth or third harmonics is greater than
[87T.K_Hm3/Hm5_OvExc] and this condition is judged as overexcitation
condition without damages to transformer. If overexcitation factor is
greater than 1.4, biased differential element is no longer being blocked by
overexcitation because transformer is damaged in this situation.
3.5.2) Work Instructions/Test Procedures :
1- Setting:
Group1:diff_prot_settings
Name
87T.En_Inst
87T.En_Biased
87T.K_Hm3_Inrush
87T.K_Hm3/Hm5_OvExc
87T.Opt_Inrush_Ident
87T.Opt_BlkMode_Inrush
Value
1
1
0.15
0.15
1
1
Unit
-------
2- Preparation:
Group1:HVS_REF_prot_settings
Group1:HVS_backup_prot_settings
Group1:LVS_backup_prot_settings
Name
LVS.64REF.En
HVS.50/51Px.En
HVS.50/51Gx.En
LVS.50/51Px.En
LVS.50/51Gx.En
Value
0
0
0
0
0
Unit
------
3- Connect I prim L1 & L2 from FREJA with the 3 phases at relay.
4- Make frequency of I prim L2 equals 150 HZ with magnitude equals 0.16
5- - Gradually decrease value of I prim until the pickup value of 3rd
harmonic.
Fundamental
100 %
Page | 355
3rd harmonic pickup
15.28 %
5th harmonic pickup
14.34 %
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Restricted Earth Fault (64REF) Protection Test
3.6.1) Purpose of Test
- Restricted earth fault protection (REF) is meant to protect a single winding
of a power transformer, and the protected winding must be earthed. In the
case of delta windings, the winding must be earthed by an earthing
transformer, which must be electrically placed between the winding and the
current transformers. REF can be applied to protection of two-winding
transformer, three-winding transformer, or auto-transformer.
- REF is a kind of differential protection, so it calculates differential
current and restrained current.
- The differential current is a vector difference of the neutral current (i.e.,
current flowing in the neutral conductor) and the residual current from the
lines. For internal faults, this difference is equal to the total earth fault
current. REF operates on the fault current only and is not dependent on
eventual load currents. This makes REF a very sensitive protection.
3.6.2) Work Instructions/Test Procedures:
1- Setting:
Group1:LVS_REF_prot_settings
Name
HVS.64REF.I_Knee
HVS.64REF.I_Biased
HVS.64REF.Slope
HVS.64REF.t_Op
HVS.64REF.En_CTS_Blk
HVS.64REF.En_NPCurr
HVS.64REF.En
Value
0.8
0.15
0.3
0.1
1
1
1
Unit
In
In
S
----
2- Preparations:
Group1:diff_prot_settings
Group1:HVS_backup_prot_settings
Group1:MVS_backup_prot_settings
Name
87T.En_Inst
87T.En_Biased
HVS.50/51Px.En
HVS.50/51Gx.En
MVS.50/51Px.En
MVS.50/51Gx.En
Value
0
0
0
0
0
0
Unit
-------
3- Connect probs of current to Freja Tester.
4- Prepare calculations of injected different values of differential current.
Page | 356
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
5- Select different points for restrain current and calculate opposite
differential current and make sure relay will trip or not if slope of
selected points equal or greater than setting slope that relay will trip.
6- Calculations:
REF's pickup criterion is:
1- Through-flowing current under undisturbed conditions or external fault:
- I_NP' flows into the protected zone from ground, 3I0Cal' leaves the
protected zone, i.e. is positive according to the definition of signs in
above figure, therefore I_NP'= 3I0Cal'.
I0d=|3I0Cal'–I_NP'|=|3I0Cal'–3I0Cal'|=0
Page | 357
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
I0r=Max (|3I0Cal'|, |I_NP'|) =|3I0Cal'|
- No differential current, but restraint current corresponds to the
through-flowing current, hence, REF does not operate.
2- Internal short-circuit:
- The following applies I_NP'=–3I0Cal', moreover |I_NP'|=|3I0Cal'|
3I0d=|3I0Cal'–I_NP'|=|3I0Cal'–(–3I0Cal’) |=2x|3I0Cal'|
3I0r=Max (|3I0Cal'|, |I_HNP) =Max(|3I0Cal'|,|3I0Cal'|)=|3I0Cal'| Differential
current are two times of restraint current and corresponding to the total fault,
hence, REF operates.
❖ REF Principle:
Page | 358
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ REF Min. pickup testing values:
❖ there are two branches at HV side (wye winding with neutral point
earthed), so there are three branches constitute REF of HV side m=3
phase
R
S
T
N (NP)
pickup
0.152
0.150
0.151
0.151
Timing (ms)
128.1
127.9
127.8
128.0
notes
En.NPcurr must be 0
❖ REF C/C’s:
0.15
𝑥1
=3
, X1 = 0.05
Let I 1 = HVS phase
Page | 359
& I 2 = NP
➢ Point (1)
I d = 0.15 = I1 – I2
I 1 = 0.2
,
I 2 = 0.05
➢ Point (2)
I d = 0.15 = I1 – I2
I 1 = 0.4
,
I 2 = 0.25
➢ Point (3)
I d = 0.15 = I1 – I2
I 1 = 0.8
,
,
I R = 0.2 = I1
,
I R = 0.4 = I1
,
I 2 = 0.65
I R = 0.8 = I1
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Point (4)
𝑦1−0.15
= 0.3
,
2−0.8
I d = 0.51 = I1 – I2
,
I1=2
,
I 2 = 1.49
y 1 = 0.51
I R = 2 = I1
➢ Point (5)
𝑦2−0.15
= 0.3
,
5−0.8
I d = 1.41 = I1 – I2
,
I1=5
,
I 2 = 3.59
y 1 = 1.41
I R = 5 = I1
❖ Testing Values:
C/C’s point
1
2
3
4
5
Page | 360
HVS
Magnitude
0.2
0.399
0.80
1.989
4.986
NP
angle
0
0
0
0
0
magnitude
0.05
0.25
0.65
1.49
3.59
angle
180
180
180
180
180
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Over Excitation (24DT) Protection Function Test
3.7.1) Purpose of Test
- Overexcitation results from excessive applied voltage, possibly in
combination with below-normal frequency. Such condition may occur
when a unit is on load but are more likely to arise when it is on open
circuit, or at a loss of load occurrence. Transformers directly connected
to generators are danger to experience overexcitation condition.
- During overexcitation, field current of transformer rises greatly to
cause excessive heating and severe damage. The transformer,
working magnetic flux density near the knee point, is subject to
overexcitation. Frequency range for normal operation is 45~55Hz
for 50Hz working frequency of power system and 55~65Hz for
60Hz working frequency of power system.
Overexcitation protection can be configured at any side of
transformer through PCS-Explorer, and it is recommended to be
equipped at the side without OLTC.
3.7.2) Work Instructions/Test Procedures:
1- Setting:
• Overexcitation protection consists of two stages definite-time
overexcitation protection and one stage inverse-time
overexcitation protection for trip purpose or alarm purpose. The
voltage for protection calculation is RMS of three phase voltages
and not affected by frequency fluctuation.
• Overexcitation inverse-time curve is sectional linear curve,
which has high adaptability.
• The overexcitation degree can be reflected by overexcitation
multiple which is calculated by voltage and frequency,
according to the following equation:
n=U*/f*
Where:
U* and f* are per unit value of voltage and frequency
respectively.
Page | 361
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ Definite-time operation criterion:
•
U*/f*>[24DTn.K_Set]
Name
24.opt_up/upp
24DT1.K_Set
24DT1.t_Op
24DT1.En
24DT2.K_Set
24DT2.t_Op
24DT2.En
Group1:HVS_Backup_prot_settings
Value
1
1.2
5
1
1.05
60
1
Unit
-S
--S
--
• Alarm eq.
N=
𝑉𝑎𝑐𝑡/𝑉𝑏𝑎𝑠𝑒
𝐹𝑎𝑐𝑡./𝐹𝑏𝑎𝑠𝑒
𝑉𝑎𝑐𝑡/100
𝐹𝑎𝑐𝑡./50
= 1.05
= 1.05
𝑽 𝒂𝒄𝒕𝒖𝒂𝒍 = 2.1 * F actual
𝑖𝑓 𝐹 = 50 𝐻𝑍
𝑡ℎ𝑒𝑛 𝑉 = 105
• Trip eq.
N=
𝑉𝑎𝑐𝑡/𝑉𝑏𝑎𝑠𝑒
𝐹𝑎𝑐𝑡./𝐹𝑏𝑎𝑠𝑒
𝑉𝑎𝑐𝑡/100
𝐹𝑎𝑐𝑡./50
= 1.2
= 1.2
𝑽 𝒂𝒄𝒕𝒖𝒂𝒍 = 2.4 * F actual
𝑖𝑓 𝐹 = 50 𝐻𝑍
❖ Testing values:
𝑡ℎ𝑒𝑛
𝑉 = 120
(by applying 3 phase voltage
Pickup
timing
Alarm ( @ 50 HZ )
60.51 V (per phase)
60.0064
Trip ( @ 50 HZ )
69.11 V (per phase)
5.03
Page | 362
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
PCS-9671S Traction Transformer
Relay Functions Procedure Test
Page | 363
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Protection Relay Technical Data (Name Plate)
- We select Traction Transformer Vv0 as example for all tests are
mentioned below.
Designation No.
PCS-9671S
CT rating
Manufacturer
Type
S/N
NR
Traction Differential relay
NRJB2176642160050
VT rating
Rated frequency
Aux. Voltage
- Functional diagram of PCS-9671S
Page | 364
400/1 A (HVS)
2000/1 A (LVS)
220/0.1 KV
50 HZ
110 DC
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) Test Equipment’s Used:
Note: Used tester types below or approved testers
S.N
Type
Make
1
Freja 300
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Software will be used for configuration and final setting tests
- We will use the PCS-Studio V1.2.2 in this instruction.
Page | 365
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
3.1) Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that protection relay is good for testing, and it doesn’t
have any damage or missing parts.
ITEM
DESCRIPTION
CHECKED
1
Inspect for any physical damage or defects.
2
Verify connections as per approved drawings.
3
Check that serial no. of relay matching with serial no. of display.
3.2) Electrical Tests:
3.2.1) Functional Test
ITEM
DESCRIPTION
CHECKED
Set Clock to local time
1
Date & time
2
4
Make Test Mode Enable under commissioning menu to check ALARM LED
Make Test Mode Enable under commissioning menu to check OUT OF SERVICE
LED
Apply any fault condition to check TRIP LED (Red)
5
Apply Test LEDs under commissioning menu to check all programmable LEDs.
6
Measured FIELD SUPPLY Voltage
3
Time maintained when Aux. Supply removed
Between terminals (+ve) – (-ve)
3.2.2) Measurement Test:
Inject values for current to make sure ratio is ok
Phase Current Accuracy HVS
CT Ratio: 400/1
Phase
Current Injected (A)
Measuring (A)
“Primary Value”
R
S
T
1∟0˚
1∟240˚
1∟120˚
398.8 ∟0˚
398.7 ∟240˚
398.7 ∟119.8˚
Phase Current Accuracy LVS1
CT Ratio 2000/1
Page | 366
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Phase
Current Injected (A)
Measuring (A)
R-N
1∟0˚
1992.7∟0˚
Phase
Current Injected (A)
Measuring (A)
R-N
1∟0˚
1992.7∟0˚
Phase Current Accuracy LVS2
CT Ratio 2000/1
Inject values for Voltage to make sure ratio is ok
Phase Voltage Accuracy HVS
VT Ratio 220,000/100
Phase
Voltage Injected (V)
Measuring (Kv)
“Primary Value”
R
S
T
57.73∟0
57.73∟240
57.73∟120
127.0 ∟0
127.01 ∟240
127.0 ∟120
Phase
Voltage Injected (V)
Measuring (KV)
R-N
57.73∟0˚
27.491∟0˚
Phase
Voltage Injected (V)
Measuring (KV)
R-N
57.73∟0˚
27.491∟0˚
Phase Voltage Accuracy LVS1
VT Ratio 27.5,000/100
Phase Voltage Accuracy LVS2
VT Ratio 27.5,000/100
Page | 367
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Transformer Differential Protection (87T) Test
3.3.1) Purpose of Test
- In power system, the power transformer is one of most valuable and
expensive equipment. If a fault occurs in the protection zone of a
transformer, current differential protection operates quickly to clear the
fault to avoid the transformer from damages or reduce the maintenance
cost as low as possible.
- We test differential protection curve for selected points and make sure
that points with slope less than setting slope, the relay not trip
3.3.2) Work Instructions/Test Procedures :
1- Preparing connection of FREJA tester.
2- Connect probs of current to Freja tester with one channel.
3- Prepare calculations of differential function.
➢ Pickup Differential Test:
❖ Setting:
Item
Opt_TractionTr
Sn_Tr1
Sn_Tr2
HVS.U1n_Plate
LVS1.U1n_Plate
LVS2.U1n_Plate
HVS. Prot.I1n
HVS. Prot.I2n
LVS1.I1n
LVS1.I2n
LVS2.I1n
LVS2.I2n
87T.I_Inst_A
87T.I_Inst_B
87T.I_Inst_C
87T.I_biased_A
87T.I_biased_B
87T.I_biased_C
87T. I_Knee1_A
Page | 368
value
Vv
40
40
220
27.5
27.5
400
1
2000
1
2000
1
3.82
6.61
3.82
0.23
0.39
0.23
0.45
unit
MVA
MVA
KV
KV
KV
A
A
A
A
A
A
A
A
A
A
A
A
A
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
87T. I_Knee1_B
87T. I_Knee1_C
87T. I_Knee2_A
87T. I_Knee2_B
87T. I_Knee2_C
87T.Slope1
87T.Slope2
87T.Slope3
87T. K_Hm2_Inrush
87T. En_Inst
87T. En_Biased
❖ Differential Equations:
Page | 369
0.79
0.45
1.36
2.36
1.36
0.3
0.5
0.75
0.15
ENABLED
ENABLED
A
A
A
A
A
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ Calculations of Differential and Restraint Currents:
• From the above equations:
It1
I`A = Kph1
It1
It2
I`B = − Kph1 − Kph2
It2
I`C = Kph2
Where:
•
•
UeH∗nH
220∗400
UeH∗nH
27.5∗2000
220∗400
Kph1 = UeL1∗nL1 =
Kph2 = UeL2∗nL2 =
27.5∗2000
= 1.6
= 1.6
Ida = IA – 0.625 It1
Idb = IB + 0.625 It1 + 0.625 It2
Idc = IC – 0.625 It2
Ira =
Irb =
Page | 370
IA+0.625 It1
2
IB−0.625 It1−0.625It2
2
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ Differential C/Cs:
• The phase A operation criterion is listed as below: The operation
criteria of phase B and phase C are similar.
Ida>[87T.I_Inst_A]
Where:
Ida is the phase A differential current.
Page | 371
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ Calculations:
• Characteristics of phase A & C:
• We will test pick up values of differential current by using
connection for HVS and LVS1 and LVS2 individually
• Calculated diff. pickup values according to the equations were
mentioned before.
- Phase A & C:
Slope = 2 =
y1
y1 = 2 x1
x1
Slope = 0.3 =
y1−0.23
x1
By solving Eq. (1) & Eq. (2), we get
Eq. (1)
y1 – 0.23 = 0.3 x1
x1 = 0.1353
Eq. (2)
y1 = 0.271
HVS min. Pickup (phase A & C) = 0.271 A
• LVS1 & LVS2 min. Pickup (phase A & C) = 0.271
= 0.434 A
0.625
Page | 372
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Characteristics of phase B:
• Calculated diff. pickup values according to the equations were
mentioned before.
- Phase B:
y1
Slope = 2 = x1
Slope = 0.3 =
y1 = 2 x1
y1−0.39
x1
Eq. (1)
y1 – 0.39 = 0.3 x1
By solving Eq. (1) & Eq. (2), we get
x1 = 0.2294
HVS min. Pickup (phase B) = 0.459 A
Eq. (2)
y1 = 0.459
➢ Note: since min. pickup of A & C less than min. pickup of B & Idb
depends on LVS1 & LVS2 currents, So the min. pickup of LVS1 &
LVS2 will be equal 0.434 for all phases
Side
HVS
LVS1
LVS2
Page | 373
Phase
A
B
C
---
Min. pickup value (A)
0.274
0.463
0.274
0.437
0.439
Timing ( ms)
28.7
28.9
28.5
28.8
28.8
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ Differential Slope Check:
• For Phase A&C:
-
To check the slope of phase A & C , we must get Id & Ir for all points then we
can get the injected currents as follows :➢ Point (2)
Let Ir = 0.225
y2−0.23
Slope = 0.3 = 0.225
y2 = 0.2975
I d = 0.2975 = IA – 0.625 It1
2Ir = 2*0.225 = IA + 0.625 It1
➢ Point (3)
Let Ir = 0.45
y3−0.23
Slope = 0.3 = 0.45
IA=0.3775
It1 = 0.122
y3 = 0.365
I d = 0.365 = IA – 0.625 It1
2Ir = 2*0.455 = IA + 0.625 It1
IA=0.632
It1 = 0.4288
➢ Point (4)
Let Ir = 0.9
y4−0.365
Slope = 0.5 = 0.9−0.45
I d = 0.59 = IA – 0.625 It1
2Ir = 2*0.9 = IA + 0.625 It1
y4 = 0.59
IA= 1.195
It1 = 0.986
➢ Point (5)
Let Ir = 2
y5−0.59
Slope = 0.5 = 1.36−0.9
Slope = 0.75 =
y6−0.82
2−1.36
I d = 1.3 = IA – 0.625 It1
2Ir = 2*2 = IA + 0.625 It1
y5 = 0.82
y6 = 1.3
IA= 2.65
It1 = 2.16
• Note: we repeat the previous calculations for Phase C and Itr2
with same calculations and record all current values as follow:
Page | 374
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Phase
point
Id
Ir
2
3
4
5
2
3
4
5
0.2975
0.365
0.59
1.3
0.2975
0.365
0.59
1.3
0.225
0.45
0.9
2
0.225
0.45
0.9
2
A
C
Injected IA
With angle 00
0.375
0.631
1.194
2.640
---
Injected IC
With angle 00
Injected It1
With angle 00
0.122
0.428
0.986
2.16
--0.374
0.630
1.193
2.646
---
Injected It2
With angle 00
--0.122
0.428
0.986
2.16
• For Phase B:
-
To check the slope of phase B , we must get Id & Ir for all points then we can get
the injected currents as follows :
➢ Point (2)
Let Ir = 0.3
y2−0.39
Slope = 0.3 = 0.3
I d = 0.48 = IB + 0.625 It1
2Ir = 2*0.3 = IB - 0.625 It1
1800)
➢ Point (3)
Let Ir = 0.45
y3−0.39
Slope = 0.3 = 0.45
I d = 0.525 = IB + 0.625 It1
2Ir = 2*0.45 = IB - 0.625 It1
1800)
➢ Point (4)
Let Ir = 0.9
y4−0.39
Slope = 0.3 = 0.79
y5−0.627
Slope = 0.5 = 0.9−0.79
I d = 0.682 = IB + 0.625 It1
2Ir = 2*0.9 = IB - 0.625 It1
with 1800)
➢ Point (5)
Let Ir = 3
y6−0.682
Slope = 0.5 = 2.36−0.9
Page | 375
y2 = 0.48
IB= 0.54
It1= - 0.096 (reversed with
y3 = 0.525
IA= 0.7125
It1= - 0.3 (reversed with
y4 = 0.627
y5 = 0.682
IA= 1.241
It1= - 0.8944 (reversed
y6 = 1.412
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Slope = 0.75 =
y7−1.412
y7 = 1.892
3−2.36
I d = 1.892 = IB + 0.625 It1
2Ir = 2*3 = IB - 0.625 It1
Phase
point
Id
Ir
2
0.48
0.3
3
0.525
0.45
4
0.682
0.9
5
1.892
3
B
Injected IB
With angle 00
0.541
0.542
0.713
0.713
1.240
1.241
3.944
3.946
IA= 3.946
It1= - 3.2864 (reversed with 1800)
Injected It1
With angle 1800
0.096
--0.30
--0.894
--3.286
---
Injected It2
With angle 1800
--0.096
--0.30
--0.894
--3.286
Inrush Current 2nd Harmonics Blocking Test
3.4.1) Purpose of Test
- The “Inrush current and 2nd harmonic detection” function recognizes
an inrush process on transformers, generates a blocking signal
for protection functions that protect the transformer (protected
object) or for protection functions that are affected in undesirable ways
when transformers are switched on, and allows a sensitive setting of
the protection functions.
- We make sure that 2nd , 3rd and 5th harmonics frequencies don’t effect
on differential protection by wrong so we block this harmonics during
connecting transformer.
- The device provides optional inrush current distinguished principles:
harmonic principle (second harmonic and third harmonic). The
discrimination of inrush current by third harmonics is independent
criterion. When an internal fault occurs and CT goes to stable
saturation, there are great third harmonic component in CT secondary
current. Because sensitive biased differential element has too high
sensitivity, the third harmonic criterion is only used to block sensitive
biased differential element to prevent it from maloperation when
[87T.En_Hm3_Blk] are set as “1”.
Page | 376
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.4.2) Work Instructions/Test Procedures:
1- Setting:
The inrush current discrimination based on harmonics is adopted
in this device. The 2nd and 3rd harmonics of differential current
can be used to distinguish inrush current. Its criteria are:
𝐼𝑑_2𝑛𝑑 > [87𝑇. 𝐾_𝐻𝑚2_𝐼𝑛𝑟𝑢𝑠ℎ] × 𝐼𝑑_1𝑠𝑡
𝐼𝑑_3𝑟𝑑 > [87𝑇. 𝐾_𝐻𝑚3_𝐼𝑛𝑟𝑢𝑠ℎ] × 𝐼𝑑_1𝑠𝑡
Where:
• 𝐼𝑑_2𝑛𝑑 is the second harmonic of phase differential current.
• 𝐼𝑑_3𝑟𝑑 is the third harmonic of phase differential current.
• 𝐼𝑑_1𝑠𝑡 is the fundamental component of corresponding phase
differential current.
• 2nd Harmonics set value = 15%
𝑇𝑅𝐼𝑃 < 𝑆𝐸𝑇 𝑉𝐴𝐿𝑈𝐸
𝐼𝑋𝐷𝑖𝑓
< 𝐵𝐿𝑂𝐶𝐾
𝐼𝐹𝐷𝑖𝑓
Where:
X: number of harmonics
F: the fundamental value
phase
2nd Harmonics set value = 15%
R
S
T
Trip ≤ 15.0% < block
Trip ≤ 15.1% < block
Trip ≤ 15.1% < block
2- Connect I prim L1 & L2 from Freja with the same phase @ relay.
3- Make frequency of I prim L2 equals 100 HZ with magnitude equals 0.16
4- Gradually decrease value of I prim until the pickup value of 2nd
harmonic.
Page | 377
Phase
Fundamental
R
S
T
1A
1A
1A
2nd harmonic (100 HZ)
pickup
0.15
0.15
0.15
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Over Excitation (24DT) Protection Function Test
3.5.1) Purpose of Test
- Overexcitation results from excessive applied voltage,
possibly in combination with below-normal frequency. Such
condition may occur when a unit is on load but are more
likely to arise when it is on open circuit, or at a loss of load
occurrence. Transformers directly connected to generators are
danger to experience overexcitation condition.
- During overexcitation, field current of transformer rises
greatly to cause excessive heating and severe damage. The
transformer, working magnetic flux density near the knee
point, is subject to overexcitation. Frequency range for normal
operation is 45~55Hz for 50Hz working frequency of power
system and 55~65Hz for 60Hz working frequency of power
system.
- Overexcitation protection can be configured at any side of
transformer through PCS-Explorer, and it is recommended to
be equipped at the side without OLTC.
3.5.2) Work Instructions/Test Procedures:
1- Setting:
• Overexcitation protection consists of two stages definite-time
overexcitation protection and one stage inverse-time
overexcitation protection for trip purpose or alarm purpose. The
voltage for protection calculation is RMS of three phase voltages
and not affected by frequency fluctuation.
• Overexcitation inverse-time curve is sectional linear curve,
which has high adaptability.
• The overexcitation degree can be reflected by overexcitation
multiple which is calculated by voltage and frequency,
according to the following equation:
n=U*/f*
- Where:
U* and f* are per unit value of voltage and frequency
respectively.
Page | 378
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ Definite-time operation criterion:
item
24DT1. K_Set
24DT1. t_Op
24DT1.EN
24DT2. K_Set
24DT2. t_Alm
24DT2.EN
•
Value
1.2
5
ENABLE
1.05
60
ENABLE
unit
Sec.
Sec.
U*/f*>[24DTn.K_Set]
• Alarm eq.
N=
𝑉𝑎𝑐𝑡/𝑉𝑏𝑎𝑠𝑒
𝐹𝑎𝑐𝑡./𝐹𝑏𝑎𝑠𝑒
𝑉𝑎𝑐𝑡/100
𝐹𝑎𝑐𝑡./50
= 1.05
= 1.05
𝑽 𝒂𝒄𝒕𝒖𝒂𝒍 = 2.1 * F actual
𝑖𝑓 𝐹 = 50 𝐻𝑍
𝑡ℎ𝑒𝑛 𝑉 = 105
• Trip eq.
N=
𝑉𝑎𝑐𝑡/𝑉𝑏𝑎𝑠𝑒
𝐹𝑎𝑐𝑡./𝐹𝑏𝑎𝑠𝑒
𝑉𝑎𝑐𝑡/100
𝐹𝑎𝑐𝑡./50
= 1.2
= 1.2
𝑽 𝒂𝒄𝒕𝒖𝒂𝒍 = 2.4 * F actual
𝑖𝑓 𝐹 = 50 𝐻𝑍
❖ Testing values:
Function
V/F alarm
V/F trip
Page | 379
𝑡ℎ𝑒𝑛
𝑉 = 120
(by applying 3 phase voltage
Freq.
50 HZ
50 HZ
Pickup Voltage
60.64
69.32
Timing (S)
60.276
5.03
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
PCS-9151C BBP Relay Protection
Functions Test Procedure
Page | 380
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Protection Relay Technical Data (Name Plate)
- We take an example for Traction-1 SS GIS double bus single breaker
arrangements which consist of 4 zone and bus coupler.
Designation No.
Manufacturer
Type
S/N
PCS-9151C
NR
Centralized Busbar Relay
CT rating
VT rating
Rated frequency
Aux. Voltage
Ref. CT=1250/1A
220/0.1 KV
50 HZ
111
dc
2) Test Equipment’s Used:
Note: Used tester types below or approved testers
S.N
Type
Make
1
Freja 300
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Software will be used for configuration and final setting tests
- We will use the PCS-Explorer V1.1.2 in this instruction.
Page | 381
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
3.1) Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that protection relay is good for testing and it doesn’t have
any damage or missing parts.
No
Description
Result
1
Visual Inspection / Rating Information
OK
2
Case Earthing
OK
3.2) Electrical Tests:
3.2.1) Functional Test
ITEM
DESCRIPTION
Set Clock to local time
1
Date & time
2
4
Make Test Mode Enable under commissioning menu to check ALARM LED
Make Test Mode Enable under commissioning menu to check OUT OF SERVICE
LED
Apply any fault condition to check TRIP LED (Red)
5
Apply Test LEDs under commissioning menu to check all programmable LEDs.
6
Measured FIELD SUPPLY Voltage
3
Time maintained when Aux. Supply removed
3.2.2) Measurement Test:
Q1
Q2
Page | 382
Between terminals (+ve) – (-ve)
CHECKED
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Note: Selection of bus disconnector Q1 or Q2 set which zone will be test.
- All measurement referred to ref. CT (1250/1)
• Bay D01&D15 (CT=300/1)
• Q1 or Q2 Closed for D01 and D15 (Power Transformers bays)
PHASE Injected current D01 reading CZ reading BB1 reading BB3 reading
R
1.0
0.24
0.24
0.24
0.24
S
1.0
0.24
0.24
0.24
0.24
T
1.0
0.24
0.24
0.24
0.24
- CZ: Check Zone
• Bay D02&D05 (CT=1250/1)
• Q1 or Q2 Closed for D02 and D05 (Underground Cables bays)
PHASE Injected current D02 reading CZ reading BB2 reading BB4 reading
R
1.0
0.99
0.99
0.99
0.99
S
1.0
0.99
0.99
0.99
0.99
T
1.0
1.00
1.00
1.00
1.00
• Bay D06&D12 (CT=400/1)
• Q1 or Q2 Closed for D06 and D12 (Traction Transformers bays)
PHASE Injected current D06 reading CZ reading BB2 reading BB4 reading
R
1.0
0.32
0.32
0.32
0.32
S
1.0
0.32
0.32
0.32
0.32
T
1.0
0.32
0.32
0.32
0.32
• Bay D11&D14 (CT=1250/1)
• Q1 or Q2 Closed for D06 and D12 (Overhead T.L bays)
PHASE Injected current D11 reading CZ reading BB1 reading BB3 reading
R
1.0
1.00
1.00
1.00
1.00
S
1.0
1.00
1.00
1.00
1.00
T
1.0
0.99
0.99
0.99
0.99
• Bay D08 (CT1=CT2=1250/1)
• CB Closed for D08
Injected
BB1
BB2
BB3
BB4
CZ
PHASE
current
reading
reading
reading
reading
reading
R
1.0
0.99
--0.99
----CT1
S
1.0
0.99
--0.99
----T
1.0
1.00
--1.00
----R
1.0
--0.99
--0.99
--CT2
S
1.0
--0.99
--0.99
--T
1.0
--1.00
--1.00
--➢ Note: For future extension bays we confirm the previous measurements.
Page | 383
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Busbar Differential Protection (87BBP) Test
3.3.1) Purpose of Test
- The busbar element is most important compartment at substation, so the
protection of it is very important to prevent any maloperation depend on any
fault, so we test its relay with two mainly functions will be discussed below
which 1st function that BBP which trip any internal fault at any check zone of
zone of busbar arrangement and 2nd function is BF (breaker fail protection
function.
- Busbar differential protection systems are used for fast and selective
protection of busbars and can be implemented both centrally.
- The basic mode of operation is based on the classic differential
protection, in which all input and output currents are monitored and used
to evaluate the operating or fault status.
3.3.2) Work Instructions/Test Procedures :
1- Preparing connection of FREJA tester.
2- Connect probs of current to Freja tester with all terminal block for
selected tested two bays in the same zone.
3- Make sure that test plug points for BBP and BF are jumper.
4- We will test each phase of bay with other phase of other bay.
5- Prepare calculations of differential current setting values for each bay.
6- Select bus disconnector Q1 or Q2 for selected check zone.
7- Start by zone 1 which has two bays D01 and D02 which have
different CTR, but we make all calculations of differential protection
referring to reference CTR=1250/1A.
8- Inject calculated current values as shown below and make sure that
selected two bays will be tripped by BBP function.
Page | 384
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Sketch Diagram for double busbar single breaker and single CT
- Sketch Diagram for difference between Check zone and Discrimination
(Selective) Zone
- Sketch Diagram for selection zone depending on disconnectors positions
Page | 385
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Pickup Differential Test:
❖ Setting:
Item
Value
87B.I_Pkp
87B.SlopeH_CZ
87B.SlopeL_CZ
87B.SlopeH_DZ
87B.SlopeL_DZ
87B.En
En_AutoRecov_DS
87B.En_DSAlm_Blk
87B.En_CTS_Blk
87B.VCE.En
1.25 A
0.5
0.3
0.6
0.5
1
1
0
1
0
❖ Calculations:
- For Ref. CT = 1250/1 & Pickup = 1.25
- Feeder pickup (CT = 1250/1)
1
= 1.25 * 1250 *
= 1.25 A
1250
- Power TR pickup (CT = 300/1)
1
1.25 * 1250 *
= 5.208 A
300
- Traction TR pickup (CT = 400/1)
1
1.25 * 1250 *
= 3.906 A
400
- Bay D01 and D15 (CT = 300/1)
PHASE
R
S
T
RST
Page | 386
PICKUP
5.231
5.232
5.233
5.225
TIMING (ms)
18.3
18.4
17.9
15.3
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Bay D02&D05 (CT = 1250/1)
PHASE
R
S
T
RST
PICKUP
1.257
1.258
1.258
1.257
- Bay D06&D12
PHASE
R
S
T
RST
- Bay D11
PHASE
R
S
T
RST
Page | 387
TIMING (ms)
18.9
18.3
18.5
17.6
(CT = 400/1)
PICKUP
3.903
3.918
3.909
3.913
TIMING (ms)
16.3
16.6
16.5
16.7
(CT = 1250/1)
PICKUP
1.256
1.255
1.258
1.255
TIMING (ms)
17.7
17.5
17.5
13.9
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ BBP Differential C/Cs:
- Operation C/C’s of steady state percentage restraint differential
element
When any phase of check zone differential current is larger than the setting, this
element will be operated.
The Operating criterion is:
Page | 388
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
❖ BBP C/C’s curve slope check:
- And we have 87B.SlopeH_CZ = 0.5 & 87B.SlopeL_DZ = 0.5 So, slope of
line should be 0.5 (Id = 0.5 I r)
Page | 389
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
-
Let I1 be current at bay D02 & I2 current at bay D14 and D02 & D14 at the same Bus
❖ Point (1)
I d = 1.25 ,
I1 – I2 = 1.25
I1 + I2 = 1.5
I r = 1.5
I1 = 1.375
❖ Point (2)
I d = 1.25 ,
I1 – I2 = 1.25
I1 + I2 = 2
, I 2 = 0.125
Ir=2
I1 = 1.625
, I 2 = 0.375
❖ Point (3)
I d = 1.25 ,
I1 – I2 = 1.25
I1 + I2 = 2.5
I1 = 1.875
❖ Point (4)
I d = 1.5 ,
I1 – I2 = 1.5
I1 + I2 = 3
Ir=3
❖ Point (5)
I d = 2.5 ,
I1 – I2 = 2.5
I1 + I2 = 5
Ir=5
point
1
2
3
4
5
Page | 390
I r = 2.5
I1 = 2.25
I1 = 3.75
Phase
R
S
T
R
S
T
R
S
T
R
S
T
R
S
T
, I 2 = 0.625
, I 2 = 0.75
, I 2 = 1.25
BAY D02 (A)
WITH ANGLE = 0
1.362
1.364
1.388
1.615
1.618
1.617
1.873
1.877
1.891
2.252
2.254
2.270
3.740
3.760
3.744
BAY D14 (A)
WITH ANGLE = 180
0.125
0.125
0.125
0.375
0.375
0.375
0.625
0.625
0.625
0.75
0.75
0.75
1.25
1.25
1.25
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Feeder Breaker Failure Protection (BFP) Test
3.4.1) Purpose of Test
- To comprehend breaker failure philosophy, we will explain this example to
comprehend purpose of breaker failure protection function test.
- For the bus protection in Figure for example, the breakers X and Y must
trip on a fault, otherwise the adjacent zone providing power to the fault
must be tripped.
- Similarly, for breaker X in Figure below, the adjacent zone H2 would
have to be tripped if breaker X did not open. However, to maintain the
speed and security in protection zones the use of timed backup
protections is minimized.
- Breaker X fails to clear a fault, all the equipment on bus H2 as well as
bus H1 would be given a trip signal via the breaker failure protection
scheme.
Page | 391
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3.4.2) Work Instructions/Test Procedures:
1- Preparing connection of FREJA tester.
2- Connect probs of current to Freja tester with all terminal block
for selected tested two bays in the same zone.
3- Check all settings for CBF protection and its Conditions as per
approved schematic drawing.
4- Check CB status and its function and logic if applicable.
5- Check CBF for mechanical protection initiate low current mode
in the relay if applicable for power transformer.
6- Check CBF initiate conditions as per approved schematic
drawing & Check transfer trip facility in CBF protection for
feeder.
7- Check phase segregated initiation if applicable (for single pole
CB)
8- Calculate Pick up / Drop OFF BF setting values as shown below
then inject each value for each bay.
Page | 392
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
9- Inject current setting value to simulate that breaker fail to trip and
still current exist with initiation binary input to BBP relay from
selected bay.
10- All B/I's and B/O's /LED configuration to be checked as per
approved scheme.
❖ Setting:
Item
50BF.t_ReTrp
50BF.t_TrpBC
50BF.t_TrpBB
Bay1.50BF.I_Set
Value
0.1 S
0.25 S
0.25 S
0.03 A
Bay2.50BF.I_Set
0.4 A
Bay4.50BF.I_Set
BC.50BF.I_Set
BC.50BF.t_TrpBB
50BF.En_Current_Ctrl
ACC_BFP.En
50BF.En
50BF.En_ReTrp
0.16 A
0.4 A
0.25 S
1
0
1
1
Notes
For bay D01 & D15
Typical for bay D02 , D05 , D11, D14 , D16 &
D17
Typical for bay D06 & D12
bay D08
❖ Calculations:
-
•
Power TR pickup (CT = 300/1) = 0.03 * 1250 * 300 = 0.125 A
•
Traction TR pickup (CT = 400/1) = 0.16 * 1250 * 400 = 0.5 A
1250
= 0.4 A
1
1
PICKUP
0.123
0.123
0.123
0.124
1ST STAGE BF TIMING (ms)
113.3
113.4
113.3
113.2
2nd STAGE BF TIMING (ms)
264.4
263.7
264.3
264.1
1ST STAGE BF TIMING (ms)
113.9
113.6
114.0
112.5
2nd STAGE BF TIMING (ms)
264.3
264.1
264.6
262.3
Bay D02&D05 : (CT= 1250/1)
PHASE
R
S
T
RST
-
Feeder pickup (CT = 1250/1) = 0.4 * 1250 *
Bay D01&D15 : (CT= 300/1)
PHASE
R
S
T
RST
-
1
•
PICKUP
0.401
0.403
0.402
0.399
Bay D06&D12 : (CT= 400/1)
Page | 393
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
PHASE
R
S
T
RST
-
PICKUP
0.504
0.506
0.505
0.504
1ST STAGE BF TIMING (ms)
119.3
118.7
119.2
117.2
2nd STAGE BF TIMING (ms)
270.2
270.1
270.8
268.6
1ST STAGE BF TIMING (ms)
119.4
119.8
120.1
117.6
2nd STAGE BF TIMING (ms)
270.9
270.6
270.6
268.9
Bay D11&D14 : (CT= 1250/1)
PHASE
R
S
T
RST
-
PICKUP
0.400
0.399
0.402
0.399
Bay D08 : (CT= 1250/1)
CT1
CT2
PHASE
PICKUP
R
S
T
RST
R
S
T
RST
0.402
0.403
0.402
0.399
0.402
0.402
0.402
0.400
1ST STAGE BF TIMING
(ms)
120.6
120.6
121.3
119.0
121.7
122.0
122.0
119.7
2nd STAGE BF TIMING
(ms)
270.2
270.5
270.8
268.7
271.3
271.3
272.0
269.3
❖ BBP&BFP Logic Test:
➢ Notes:
• BFP has topology logic as same as of BBP for tripping zones.
• For each bay table, other bays are connected as follows : odd
bays at Q1 & even bays at Q2
• BBP Block Selector is checked.
• BF Block Selector is checked.
• If we have DS status alarm, BBP will use last state of DS.
Page | 394
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Bay D01:
Bay D01
Q1
Q2
OPEN
OPEN
CLOSE
OPEN
CLOSE
CLOSE
OPEN
CLOSE
CLOSE
CLOSE
Q1A
Q1B
Q2A
Q2B
BC CB
BBP & BFP ACTION
--OPEN
CLOSE
CLOSE
----OPEN
CLOSE
---
---
------OPEN
NO TRIP
CLOSE
CLOSE
---
---
---
---
CLOSE
OPEN
CLOSE
CLOSE
--OPEN
CLOSE
----OPEN
CLOSE
CLOSE
CLOSE
TRIP BB1A
TRIP BB1A & BB1B
TRIP BB1A , BB1B &
BC
TRIP BB2A
TRIP BB2A&BB2B
TRIP BB2A , BB2B &
BC
TRIP BB1A & BB2A
TRIP BB1A , BB1B ,
BB2A & BB2B
OPEN
CLOSE
--CLOSE
OPEN
CLOSE
--CLOSE
---
Q1A
Q1B
Q2A
Q2B
BC CB
BBP & BF ACTION
----OPEN
CLOSE
--OPEN
CLOSE
CLOSE
-----
-----
------OPEN
NO TRIP
CLOSE
CLOSE
---
• Bay D11
Bay D11
Q1
Q2
OPEN
OPEN
CLOSE
OPEN
CLOSE
CLOSE
Page | 395
OPEsN
CLOSE
CLOSE
CLOSE
---
--CLOSE
---
OPEN
CLOSE
CLOSE
--OPEN
CLOSE
OPEN
CLOSE
CLOSE
----OPEN
CLOSE
CLOSE
CLOSE
--CLOSE
OPEN
CLOSE
-----
TRIP BB1B
TRIP BB1A & BB1B
TRIP BB1A , BB1B &
BC
TRIP BB2B
TRIP BB2A&BB2B
TRIP BB2A , BB2B &
BC
TRIP BB1B & BB2B
TRIP BB1A , BB1B ,
BB2A & BB2B
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
PCS-9151 ATS Relay Protection
Functions Procedure Test
Page | 396
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Protection Relay Technical Data (Name Plate)
- We take an example for Traction-1 SS ATS between two traction
transformers 220/27.5Kv
Designation No.
Manufacturer
Type
PCS-9651
NR
ATS
Rated frequency
Aux. Voltage
Traction 1&2 VT
Bus 1&2 VT
50 HZ
110 Vdc
220,000/100
27,500/100 V
2) Test Equipment’s Used:
Note: Used tester types below or approved testers
S.N
Type
Make
1
Freja 300
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Software will be used for configuration and final setting tests
- We will use the PCS-Explorer V1.1.2 in this instruction.
Page | 397
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
3.1) Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that protection relay is good for testing, and it doesn’t
have any damage or missing parts.
No
Description
Result
1
Visual Inspection / Rating Information
OK
2
Case Earthing
OK
3.2) Electrical Tests:
3.2.1) Functional Test
ITEM
DESCRIPTION
CHECKED
Set Clock to local time
1
Date & time
2
4
Make Test Mode Enable under commissioning menu to check ALARM LED
Make Test Mode Enable under commissioning menu to check OUT OF SERVICE
LED
Apply any fault condition to check TRIP LED (Red)
5
Apply Test LEDs under commissioning menu to check all programmable LEDs.
6
Measured FIELD SUPPLY Voltage
3
Time maintained when Aux. Supply removed
Between terminals (+ve) – (-ve)
3.2.2) Measurement Test:
-
Traction 1 measurement accuracy (VT = 220,000/100)
PHASE
Injection voltage (V)
Measured voltage (KV)
R
57.74
127.054
S
57.74
126.992
T
57.74
127.131
- Traction 2 measurement accuracy (VT = 220,000/100)
PHASE
R
S
T
Page | 398
Injection voltage (V)
57.74
57.74
57.74
Measured voltage (KV)
127.093
127.098
127.027
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
-
6.1-
Bus 1 measurement accuracy (VT = 27,500/100)
PHASE
Injection voltage (V)
R
57.737
Bus 2 measurement accuracy (VT = 27,500/100)
Measured voltage (KV)
27.521
PHASE
R
Measured voltage (KV)
27.505
Injection voltage (V)
57.737
[
Automatic Transfer Switch (ATS) Test
3.2.1) Purpose of Test
- Voltage decrease or complete supply interruption represent the most
important and critical problems for quality of energy supply today, it is
especially true that voltage disturbances of electronic control systems and
other sensitive installation can lead to complete loss of productions and long
stoppage time.
to realize a permeant availability, the load is supplied by at least two different
power supplies which are independent from one another, and which are
equipped with automatic transfer switch ATS devices.
- We test ATS function for protection relay to test all procedures of
operating individually to make sure that relay device will operate
successfully for applied setting values and logic diagram.
3.2.2) Work Instructions/Test Procedures :
1- Preparing connection of FREJA tester.
2- Connect probs of current and voltage to Freja tester.
3- Review the setting and check all setting values are matched with
actual setting.
4- Setting:
Item
Power1.U1n
Power1.U2n
Power2.U1n
Power2.U2n
Bus1.U1n
Bus1.U2n
Bus2.U1n
Bus2.U2n
Power.U_Dd
Bus1.U_Dd
Bus2.U_Dd
Page | 399
Value
220 KV
100 V
220 KV
100 V
27.5 KV
100 V
27.5 KV
100 V
50 V
50 V
50 V
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Power.U_LV
Bus1.U_LV
Bus2.U_LV
Power.ATS.t_Op_VoltLoss
ATS.t_Reclaim
7QF.EN_out
7QF.EN_out
Page | 400
70 V
70 V
70 V
3 sec
15 sec
1
1
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
5- Review ATS logic Procedure from manual as follow and test
according to it:
➢ According to relay manual we have two modes for ATS function depending
on which side is energize and other side is ready. In this test we will use
mode 1.
➢ The normal situation The CB1, CB3, CB5 are all close and CB2, CB4,
CB6 are open. CB7 and CB8 are close and feed to OCS but they don’t
attend to the ATS procedure.
➢ There have 2 fault which will cause ATS operation, one is transformer
fault (for example, mechanical fault) and the other is 220kV loss.
➢ Note: the CB is act one by one, that is, the PCS-9651 sends tripping
command to one CB first, and then sends tripping command to the next
CB after receiving the CB position signal. The time of each CB is
200ms.
➢ The procedure is executed automatically. MT1 fault (MT2 the same)
• In case of 87T (transformer differential protection) or MR
(mechanical protection) protection action, send tripping
command, trip the CB1, CB3 and CB5 simultaneously and send
start ATS signal to ATS device
PCS-9651.
Page | 401
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• After receiving the ATS signal, delay 50ms, the PCS-9651 will
trip CB3, CB5, CB1 again and close CB2, CB4, CB6 orderly.
• The voltage of the 220kV incoming power1 loss (ATS1), ATS2 is
the same
➢ Ready Conditions:
• All the following conditions are satisfied for an appoint time (the setting
[ATS.t_Reclaim]), the ATS1 will be ready for operation.
o CB1, CB3 and CB5 are closed, CB2, CB4 and CB6 are opened.
o “Powerx.Uab_Sec”>[Power.U_Lv],
“Powerx.Ubc_Sec”>[Power.U_Lv] and
“Powerx.Uca_Sec”>[Power.U_Lv].
- “Powerx.Uab_Sec” is the secondary value of phase A to phase B
voltage of the incoming powerx.
- “Powerx.Ubc_Sec” is the secondary value of phase B to phase C
voltage of the incoming powerx.
- “Powerx.Uca_Sec” is the secondary value of phase C to phase A
voltage of the incoming powerx.
- x Is 1 and 2.
o “Bus1.U_Sec”>[Bus1.U_Lv] and “Bus2.U_Sec”>[Bus2.U_Lv].
- “Bus1.U_Sec” is the secondary value of the busbar1 voltage.
- “Bus2.U_Sec” is the secondary value of the busbar2 voltage.
➢ Lockout Conditions:
• If anyone of the following conditions is satisfied, the ATS1 function
will be blocked.
o The binary input [BI_BlkATS] is “1”, or [BI_Maintenance_Power]
is “1”, or [BI_Maintenance_Tr] is “1”.
o The logic setting [En_ATS1] is “0”.
o The voltage of the incoming power2 is lost for at least 15s.
o Anyone of the circuit breakers CB1, CB2, CB3, CB4, CB5 or CB6
is not in normal operation state of this mode.
o Anyone of the circuit breakers and disconnector switches refuses to
operate during the ATS1 operation.
o The ATS1 Operate Successfully.
o The device blocked and LED indicator “HEALTHY” is off.
Page | 402
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
o The position of anyone of the circuit breakers and disconnectors
switches is abnormal.
o If the setting [CB7.En_Out] 、[CB8.En_Out] set as 1, the PCS9651 will not operate to trip CB7 and CB8 when operate.
➢ Operation Process:
• After ATS1 is ready for operation, if the following three conditions are
satisfied at the same time, the fault detector of ATS1 will pick up, and
the PCS-9651 will operate to trip CB3, CB5 and CB1 orderly, then
close CB2, CB4 and CB6 orderly after the time delay
[Power.ATS.t_Op_VoltLoss].
o “Power1.Uab_Sec”<[Power.U_Dd],
“Power1.Ubc_Sec”<[Power.U_Dd],
“Power1.Uca_Sec”<[Power.U_Dd],
o “Bus1.U_Sec”<[Bus1.U_Dd],
“Bus2.U_Sec”<[Bus2.U_Dd]
o “Power2.Uab_Sec”>[Power.U_Lv],
“Power2.Ubc_Sec”>[Power.U_Lv],
“Power2.Uca_Sec”>[Power.U_Lv],
• If the above circuit breakers operation is successful, the binary output
signal [ATS.Sig_Succeeded] will be sent, otherwise the ATS1 function
the ATS1 function returns
6- After reviewing logic procedure, we will be ready to test ATS function
as follow:
• Assume that:
- CB1, CB3 & CB5 are Closed.
- CB2, CB4 & CB6 are open.
Traction 1
Dead
Value
28.80
Page | 403
Bus 1 Dead
Bus 2 Dead
Value(ph.=line) Value(ph.=line)
value
value
49.90
49.87
Traction 2
Live Value
Action
40.50
CB 3 Trip time = 3002 ms
CB 5 Trip time = 3078 ms
CB 1 Trip time = 3153 ms
CB 2 closing time = 3238 ms
CB 4 closing time = 3386 ms
CB 6 closing time = 3471 ms
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Assume that:
- CB2, CB4 & CB6 are Closed.
- CB1, CB3 & CB5 are open.
Traction 2
Dead Value
28.80
Bus 1 Dead
Bus 2 Dead
Value(ph.=line) Value(ph.=line)
value
value
49.90
49.85
Traction 1 Live
Value
Action
40.50
CB 4 Trip time = 3001 ms
CB 6 Trip time = 3076 ms
CB 2 Trip time = 3151 ms
CB 1 closing time = 3236
ms
CB 3 closing time = 3374
ms
CB 5 closing time = 3457
ms
• Assume that:
- CB1, CB3 & CB5 are Closed
- CB2, CB4 & CB6 are open
- All voltage is OK, then Protection Trip occurred for Traction
Action
CB 3 Trip time = 0051 ms
CB 5 Trip time = 0127 ms
CB 1 Trip time = 0203 ms
CB 2 closing time = 0287 ms
CB 4 closing time = 0437 ms
CB 6 closing time = 0522 ms
• Assume that:
- CB2, CB4 & CB6 are Closed
- CB1, CB3 & CB5 are open
- All voltage is OK, then Protection Trip occurred for Traction
Action
CB 4 Trip time = 0052 ms
CB 6 Trip time = 0128 ms
CB 2 Trip time = 0205 ms
CB 1 closing time = 0291 ms
CB 3 closing time = 0414 ms
CB 5 closing time = 0496 ms
• All Binary Inputs checked as per schematic diagram.
• All Binary Outputs checked as per schematic diagram.
Page | 404
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
MR TAPCON 260 AVR Relay Functions
Procedure Test
Page | 405
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Protection Relay Technical Data (Name Plate)
- We take an example for Traction-1 SS Power Transformer 220/20Kv
Designation No.
Manufacturer
Type
TAPCON 260 PRO
MR
AVR
Rated frequency
Aux. Voltage
CT
VT
50 HZ
110 Vdc
2) Test Equipment’s Used:
Note: Used tester types below or approved testers
S.N
Type
Make
1
Freja 300
Megger
Calibration date
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
➢ Software will be used for configuration and final setting tests
- We will use the TAPCON 260 MR Software.
Page | 406
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
3) TESTS:
3.1) Mechanical Check and Visual Inspection:
3.1.1) Purpose of test:
- Make sure that protection relay is good for testing, and it doesn’t
have any damage or missing parts.
No
Description
Result
1
Visual Inspection / Rating Information
OK
2
Case Earthing
OK
3.3) Electrical Tests:
3.2.1) Functional Test
ITEM
DESCRIPTION
CHECKED
Set Clock to local time
1
Date & time
2
4
Make Test Mode Enable under commissioning menu to check ALARM LED
Make Test Mode Enable under commissioning menu to check OUT OF SERVICE
LED
Apply any fault condition to check TRIP LED (Red)
5
Apply Test LEDs under commissioning menu to check all programmable LEDs.
6
Measured FIELD SUPPLY Voltage
3
Time maintained when Aux. Supply removed
Between terminals (+ve) – (-ve)
3.2.2) Measurement Test:
➢ Current measurement accuracy (CT = 1200/1)
PHASE
R
Injection current (A)
1
Measured current (A)
1200
➢ Voltage measurement accuracy (VT = 10,000/100)
PHASE
RS
[
Page | 407
Injection Voltage (V)
100
Measured Voltage (KV)
10
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Automatic Voltage Regulator (AVR) Test
**We AVR panel with MR TAPCON 260
3.3.1) Purpose of Test
- The automatic voltage regulator is used to regulate the voltage. It takes the
fluctuate voltage and changes them into a constant voltage. The fluctuation
in the voltage mainly occurs due to the variation in load on the supply
system. The variation in voltage damages the equipment of the power
system. The variation in the voltage can be controlled by installing the
voltage control equipment at several places likes near the transformers,
generator, feeders, etc., The voltage regulator is provided in more than one
point in the power system for controlling the voltage variations.
- AVR panel is installed for remote automatic control of voltage of power
transformers HV side.
- AVR relay control the voltage by changing no. of taps of HV winding of
Power transformer to maintain same voltage of low side as desired value.
- Control of voltage is performed at onload process by using OLTC (onload tap
change) which is placed at high voltage winding.
3.3.2) Work Instructions/Test Procedures :
1- Preparing connection of FREJA tester.
2- Connect probs of current and voltage to Freja tester.
3- Review the setting and check all setting values are matched with actual setting.
4- Open software of TAPCON 260 as follow:
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Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
• Open the MR TAPCON 260 software
•
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Click on Establish connect to device.
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 410
•
Click on Connect.
•
Downloading the settings
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
•
-
Select the Device group, Device name & Name.
This Device ident code is last four digits from the relay serial
number. Then click finish.
• Here we have the settings of TAPCON 260. Right click on the AVR
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Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
5- Setting:
Item
Normset
Desired voltage Level 1
Bandwidth
Delay time T1
Delay time T2
Over voltage setting
Under voltage Setting
Over current setting
Under Current Setting
CTR
VTR
Pulse time
Value
Off
100 V
±5%
5 sec (DT)
10 sec
110 V
90 V
110 %
5%
1200/1
10000/100
1.5 sec
6- Insert setting values at software as follow:
• Set the desired value 1 as 100 V, Set the bandwidth value as 5%.
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Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Page | 413
•
Set the overcurrent settings 110%
•
Set the Over Voltage & undervoltage setting 110% & 90% respectively.
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
•
Set the primary current & Voltage.
• Here you can check your all settings:
Page | 414
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
7- Test raise and lower and other functions by using FREJA 300 tester
software as follow:
➢ Bandwidth Check:
- Connect the voltage and current leads as per given schemes You must inject
the secondary voltage as per your setting.
- Ramp from 100 V to 94 V it will start raising the pulse when it reaches
95 V.
Page | 415
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- Ramp from 100 V to 106 V it will start Lower the pulse when it reaches
105 V.
➢ Band width Test:
condition
pickup
T1
T2
Raise voltage
95.02 V
6.16 sec
16.23 sec
Lower voltage
105.1 V
6.15 sec
16.47 sec
Page | 416
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Undervoltage & Overvoltage Test
- To test the undervoltage ramp from 100 V to 85V it will give you trip at less
than 90 V
Page | 417
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
- To test the overvoltage ramp from 100 V to 115V it will give you trip at
more than 110 V.
Page | 418
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Overcurrent Test
- To test the Overcurrent ramp secondary current 1A to 1.2 A, it will give you
trip at 1320 A as primary in AVR front screen.
➢ Blocking conditions Test:
Condition
Pickup
Over Voltage
110.9 V
Under Voltage
90.18 V
Over Current
1.12 A
Under Current
0.052 A
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Result
AVR
Operation
Blocked
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
Protection Relays Tests
End to End Procedure Test
Page | 420
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
1) Test Equipment’s Used:
Note: Used tester types below or approved testers.
S.N
Type
Make
1
Freja 300
Megger
** ALL CALIBRATION CERTIFICATES SHOULD BE PROVIDED.
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Calibration date
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
2) TESTS:
Mechanical and Visual Inspection Test:
ITEM
DESCRIPTION
1
Inspect for any physical damage or defects.
2
Verify connections as per approved drawings.
3
Check that serial no. of relay matching with serial no. of display.
ITEM
DESCRIPTION
Set Clock to local time
1
Date & time
Time maintained when Aux. Supply removed
2
Make Test Mode Enable under commissioning menu to check ALARM LED
3
Make Test Mode Enable under commissioning menu to check OUT OF SERVICE
LED
4
Apply any fault condition to check TRIP LED (Red)
5
Apply Test LEDs under commissioning menu to check all programmable LEDs.
6
Measured FIELD SUPPLY Voltage
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Between terminals (+ve) – (-ve)
CHECKED
CHECKED
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
End To End of Differential Over Head T.L Test:
2.2.1) Purpose of test:
- Check for differential protection trips for two protection relays for
two connected stepdown substations.
- Check for logic interlocks between two substations.
2.2.2) Work Instructions/Test Procedures:
1- Connect Freja 300 tester kit to the protection relay for two
substation and injected measurements and pickup current
values for differential biased 1 and 2 values and check that
two protection relays will be operated, and two circuit
breakers will be tripped by differential function then repeat
this step for remote relay and check for all points.
2- Disconnect fiber optic cable and make sure its signal will be
sent to two protection relays for local and remote
substations.
3- Inject same values of differential protection setting and
make sure that local circuit breaker will be tripped by
backup protection function and differential function will be
blocked and remote circuit breaker will not be tripped by
any protection function.
4- By disconnecting fiber optic cable, check interlocks between two
substations that no interlocks will be achieved.
5- Evaluate all case sin test format tables as shown below.
Page | 423
Inspection Test Plan
ITP Guidebook
Safety Precautions: (1) Safety tagging shall be implemented (2) Isolate the area by safety warning tape (3) Keep a safe distance from the device
being tested (4) Wear appropriate personal protective equipment prior to starting any testing activity (5) Implementation proper grounding.
➢ Measurement Check:
- Injection from local end:
Phase
Current Injected
(A)
Local end Reading
(A)
Remote End
Reading (A)
Remarks
Local end Reading
(A)
Remote End
Reading (A)
Remarks
R
S
T
- Injection from remote end:
Phase
Current Injected
(A)
R
S
T
➢
Line Differential Test:
•
•
Check That the local and remote end Circuit breakers are closed.
Check that the fiber optic cable is ok by checking the (alm. fiber not come in the relay
alarms).
Injection Side
Current Injected
(A)
Local End
Remote End
•
Local End Circuit
Breaker
Tripped
Tripped
Remote End
Circuit Breaker
Tripped
Tripped
Remarks
OK
OK
If The Fiber optic cable Not OK and the Alm.Fiber is coming in the relay alarms
Injection Side
Local End
Remote End
Current Injected
(A)
Local End Circuit
Breaker
Tripped
No Trip
Remote End
Circuit Breaker
No Trip
Tripped
Remarks
OK
OK
6- Attach screenshots from protection relays for interlocks logic
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