Transformer differential

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Q U A L I T Y P R O C E D U R E

TITLE : Transformer Differential Protection Testing for Devices and

Schemes. REF.No : TP/TPD/PFS/TPC/QP - 13 Copy No. : AMENDMENTS ISSUE / REVISIO N NO.

SUBJECT OF THE AMENDMENT REVIEWED BY & SIGNATURE

AUTHORIZED BY & SIGNATURE

DATE

1/0 New Procedure Prepared

2/0 Entire procedure has been amended to incorporate process change and restructuring within the department.

This procedure supersedes the old procedure No. TP/TPD/TPC/QP 13

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C O N T E N T S 1.0 PURPOSE 2.0 SCOPE 3.0 DEFINITIONS 4.0 CROSS REFERENCES 5.0 RESPONSIBILITY 6.0 PROCEDURE 7.0 RECORDS 8.0 DISTRIBUTION 9.0 ATTACHMENTS

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1.0 PURPOSE

1.1 This procedure is to explain in detail the steps to be followed for commissioning of Transformer differential protection devices and schemes and to facilitate effective control of documents.

2.0 SCOPE

2.1 This procedure applies to commissioning of Transformer differential protection devices and schemes in 132 kV and 400 kV substations.

3.0 DEFINITIONS

3.1 Approved drawing: The general arrangement, scheme drawings which are approved by TPE with status code A or B to execute the work at site. 3.2 Approved setting : The approved values, parameters & configuration of the protection

relays issued by PCS to be implemented in the protection relays before putting the relay in service.

3.3 BI : Binary Inputs. 3.3 BO : Binary Outputs. 3.4 CB : Circuit breaker 3.5 CT : Current Transformer.

3.6 CM-TPC: Commissioning Manager-Transmission Protection Commissioning. 3.7 DO : Drop Off.

3.8 HV : High Voltage.

3.9 IDT : Inter-Distribution Transformer 3.10 LV : Low Voltage.

3.11 LED: Light Emitting Diode.

3.12 M-TPC: Manager- Transmission Protection Commissioning. 3.13 PCS : Protection Calculation Setting, a section of TPD. 3.14 POC : Primary Operating Current.

3.15 PPE : Personal Protective Equipments. 3.16 PU : Pick-Up.

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3.19 TPD : Transmission Protection Department. 3.20 VP-TP : Vice President-Transmission Protection.

3.21 Testing Engineer: Engineer from contractor or manufacturer who performs the test as per this procedure.

3.22 Witness Engineer: Engineer from DEWA / approved consultant who witness the test

4.0 CROSS REFERENCES

4.1 Nil 4.2

5.0 RESPONSIBILITY

5.1 VP-TP : VP-TP is responsible for approval & modification of this procedure. 5.2 M-TPC : M-TPC is responsible for implementation of this procedure.

5.3 CM-TPC : CM-TPC is responsible to plan testing activities as per the details of this procedure.

5.4 Witness Engineer : Witness engineer is responsible to witness the testing of relay/scheme

6.0 PROCEDURE 6.1 General.

6.1.1 Ensure the availability of approved setting for the protection device from TPD-PCS. The RSI number of the setting template to be filled in the test formats

6.1.2 The TPC Witness engineer ensures the calibration certificate of measuring equipments used for testing are available at site and ensures the availability of relevant test sheets (given as attachment) prior to performing the site testing. The testing instruments details shall be recorded in the test report.

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6.1.3 Establish a communication between the relay and the computer (lap-top) for uploading / down loading settings using the appropriate application software and connecting cables.

6.1.4 Download the default settings from the relay to computer and update the approved settings with date and time.

6.1.5 Configure the input / output mappings in the application software as per the approved drawings. The date and time setting to be updated as actual 6.1.6 Upload the updated file to the relay and confirm the relay is healthy.

6.1.7 Relay soft setting and configuration file should be downloaded from the protection relay finally and saved with the filename provided on the footer of the specific setting template. A printout of the same shall be signed and attached with the test report. The setting template sheet, test reports are also to be signed by the

contractor and the witness engineer.

6.1.8 Test report shall be filled during testing and the same shall be signed on the same day of testing.

6.2 Protection Device testing.

Device - Siemens relay 7UT613 (Refer attachment 13:A01)

6.2.1 General Data and Inspection.

• The testing engineer has to fill the General data (Relay Type, Serial No, Firmware Version, Rated Current etc.) as mentioned in the test format.

• A general visual inspection is carried out to confirm the relay installation and wirings are carried out as per the approved drawings.

• The jumper settings to be set for the rated voltage, current and correct pick up voltage of the binary inputs. This is to be done as per Siemens relay 7UT613 manual.

6.2.2 Configuration of Protection functions:

• Relay configuration is done to enable only those protection functions which are recommended in the relay setting template.

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6.2.3 Measurements Checks:

• Use the secondary injection test kit to inject current in HV side CT ‘R’ phase and note down the relay display reading. Repeat the current injection in Y & B phases and note down the display readings in the test format.

• Repeat same for LV side CT. 6.2.4 Relay Pick Up values:

• Using the secondary injection test kit, gradually raise the current in R phase of HV side CT till the relay picks up. Note the value of differential pick-up. Repeat the same for the other phases in HV side CT. Repeat the same for LV side CT. 6.2.5 Timing Tests:

• Inject current 1.5 times setting current as mentioned in test format in R phase and note down the operating times values in the test format. The operating time should be less than that indicated in the test format.

• Repeat the test for other phases. 6.2.6 Differential protection testing:

• Bias characteristics are checked by injecting a balanced current in HV side and LV side CT secondary, and then gradually increasing current in HV side till differential pickup. Record the trip value of current in CT side-1.

• Inject 4 times I diff>> setting current in each phase and check trip time. Record the values. Also record LED operation.

• Repeat the test for other phases. 6.2.7 Testing 2’nd Harmonic restraint.

• 2nd harmonic blocking is set at 15%.

• 16% 2nd Harmonic is generated using the secondary injection kit and applied to relay for 5 periods (100 milli sec) and check differential is blocking.

• Note the value of set harmonic percentage in test kit. 6.2.8 To check cross block feature

• Inject 1 amp at 50 hertz in R phase and B phase along with 0.3 amps at 100 Hertz in Y phase.

• With cross block feature off, the relay should trip by R phase and B phase differential protection.

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• Set cross block feature “YES” and time for cross block as 80 milli sec. The differential trip will be blocked for 80 milli sec.

6.2.9 Testing of Add on Stabilisation for External faults: (Siemens 7UT612) • The test is carried out to check CT saturation detection during the

duration of add on stabilisation as explained in the test format. 6.2.10 Binary Inputs and Outputs:

• Record the function of BI/BO in the test format. Apply voltage and check the BI is functioning.

• Each BO to be checked separately by operating the particular function to which it is assigned. The BO is tested by checking the continuity between contacts using a multi-meter.

• Each LED indications are to be checked separately by operating the particular function to which it is assigned. LED resetting operation is checked by manually resetting the indications.

6.2.11 Other Checks:

• Disturbance recorder and event recorder from the relay are to be down loaded to the computer (laptop) and the printout to be attached with the test report.

• Confirm operation of trip relay by inserting the appropriate trip link. Also confirm signals to fault recorder and SCADA system are send from the relay.

Device - Areva relay Micom P 632(Refer attachment TP/TPD/PFS/TPC/QP- 13:A02)

6.2.12 Relay Data and General Inspection.

6.2.13 LED, Binary Inputs and Outputs:

• Record the function of BI/BO in the test format. Apply voltage and check the BI is functioning.

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• Use the secondary injection test kit to inject 1 amps current in HV side CT’s and note down the relay display reading. Repeat the current injection in LV side CT’s and note down the display readings in the test format. Compare with expected current.

6.2.15 Differential protection checks.

• Differential protection settings are entered in the test report.

• Using the secondary injection test kit, gradually raise the current in R phase of HV side CT till the relay picks up. Note the value of differential pick-up. Repeat the same for the R phase of LV side CT.

• Check 3 phase pickup by gradually raising the current in all phases in HV side CT till the relay picks up. Repeat the same for LV side CT.

6.2.16 Differential protection checks:

• Bias characteristics are checked by injecting a balanced current in HV side and LV side CT secondary, and then gradually increasing current in HV side till differential pickup. Record the trip value of current in CT side-1.

6.2.17 CT saturation check: (MICOM P632)

• CT saturation Check is tested by applying 1 Amps at 100 Hz to R, Y and B phases. The setting of vector group will be “YY0”, setting for 2nd

harmonic should be “disable” and zero sequence filter “OFF” .Confirm the relay detect CT saturation and Block differential function.

6.2.18 Timing Tests:

• Inject current 1.0 amp current as mentioned in test format in HV side R phase and note down the operating time value in the test format. The operating time should be

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• Repeat the test for other phases in HV side. Repeat the same for LV side also. 6.2.19 Testing 2’nd Harmonic restraint.

• 2nd harmonic blocking is set at 15%.

• 16% 2nd Harmonic is generated using the secondary injection kit is applied to HV side R phase of relay and check differential is blocking. Relay should not trip. • Reduce harmonics percentage in the injected current till the relay trips. Record the

value in the test format.

• Repeat the test for HV side Y and B phase. 6.2.20 Differential High set (I diff>>)test:

• Inject in R phase a current below “I diff>> setting and observe the tripping time. The tripping time should be the normal differential tripping time.

• Repeat injection, gradually raising the current till the tripping time is less than the differential operating current. Record the threshold value of “I diff>>” pickup current.

• The operating time of HIGH SET will be tested by injecting 2 times of high set differential setting current and record the time.

6.2.21 Other Checks

Device – Duo Bias M (Refer attachment TP/TPD/PFS/TPC/QP-13:A03)

6.2.22 Relay Data and General Inspection.

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• Use the secondary injection test kit to inject 1 amps current in HV side CT’s and note down the relay display reading. Repeat the current injection in LV side CT’s and note down the display readings in the test format. Compare with expected current.

6.2.24 Differential bias characteristic.

• Bias characteristics are checked by injecting a bias current as reference, and then gradually increasing the operating current till differential pickup. Verify results with expected and measured operating values. The readings are taken keeping bias currents at 0, 1, 1.5, 2 and 4 amps for each phase.

6.2.25 Timing Tests:

• Inject current 3 times setting current or as mentioned in test format in R phase and note down the operating times values in the test format. Repeat the test for other phases.

6.2.26 Differential High set test:

• The operating time of HIGH SET will be tested by injecting 2 times of high set differential setting current and record the time. Repeat the test for other phases. 6.2.27 Harmonic Block test

• Inject a current higher than differential setting with a harmonic content of more than harmonic block settings in red phase and see that the relay blocks tripping and gives correct LED indication.

• Repeat the Injection in the other Y & B phases. 6.2.28 LED, Binary Inputs and Outputs:

• Record the terminal numbers of BI/BO in the test format. Apply voltage and check the BI is functioning.

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6.2.29 Other Checks:

3.3 Protection Scheme testing. Note:

For Sensitivity test (refer attachment Transformer Differential Sensitivity Test Report.- TP/TPD/PFS/TPC/QP-13:A04)

For Stability test (refer attachment Transformer Differential Stability Test Report.- TP/TPD/PFS/TPC/QP-13:A05)

6.3.1 To avoid the operation of REF (High Imp) during the sensitivity and stability tests, ensure the REF and stabilizing resistor are by passed.

6.3.2 Sensitivity on HV Side

• The differential relay settings and calculated value of Primary Operating Current (POC) are recorded in test format.

• Primary current shall be injected on HV Side R Phase to earth and the same shall be increased slowly form zero till the differential protection Operates. The Primary current at which the protection operates is the minimum Primary Operating Current for R Phase. Record on test formats the corresponding secondary currents and relay display readings at this POC. The value shall be with in the limits of tolerance. The same shall be confirmed for Y and B Phases.

• The same injection is repeated for phase to phase injection (R-Y, Y-B and B-R) and the POC is compared again with the calculated values.

• When there are 2 sets of CT’s on the HV side, the values are recorded for each set as Bus-1 and Bus-2 CT’s.

6.3.3 Sensitivity on LV Side

• Primary current shall be injected to LV side CT’s to repeat the test as in 6.3.2, to find sensitivity of LV side.

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• Stability test in carried out as per the details given below. A 3 phase 415 Volts shall be applied on LV (11kV Side) side of Transformer and all three phases of HV Side shall be shorted and earthed. Actual values of current on HV and LV shall be compared with the calculated value based on percentage impedance of

transformer. The differential and bias currents will be compared with the primary current values.

• Identify the IDT for the differential relay under test.

• Isolate tripping to both HV and LV CB’s from differential relay.

• Isolate the section of 11 kV where this IDT-LV is connected by keeping all CB’s in test position and opening the bus earth switch.

• 132 kV IDT bay is connected to either bus-1 or bus-2 and the connected bus earth switch is closed. Line isolator and CB is kept closed for IDT.

• Supply 3 phase 415 Volts to one of the outgoing feeder in that section of 11 kV. Rack in the CB of that bay to service and close CB. 11 kV section is now energised with 415 V supply.

• Rack in the CB of the incomer where IDT-LV is connected. Close the CB to circulate a current in primary circuit.

• Record all values of primary and secondary currents including the Differential current and Restraint currents in the test formats. These are the normal values. The differential Current shall be zero and Restraint current shall be high. The

currents are recorded while keeping the tap-changer in extreme low tap, middle tap and high tap.

• Keep the tap changer in middle tap. The R phase of HV side CT shall be reversed without opening the CT. Record all values of primary and secondary currents including the Differential current and Restraint currents in the test formats. In this condition the Differential current shall be predominant and Restraint current shall be less. If the Differential current is more than the setting, the protections shall operate. After recording the currents, the R phase shall be normalized. Confirm the currents are normal values again. The same shall be repeated for Y and B Phase.

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• Keeping the tap changer in middle tap, the R phase of LV side CT shall be

reversed now without opening the CT and record all the above values as done for HV side CT’s. Again in this condition, the Differential current shall be high and Restraint currents shall be less. If the Differential current is more than the setting the protections shall operate. After Recording the currents the R phase shall be normalized and confirm the currents are in order. The same shall be repeated for Y and B Phase.

• If HV side is provided with 2 sets of CT’s, each set is compared individually with the LV side CT’s. Also normal values are also taken for each set of CT’s in the

beginning and end of testing.

• After normalizing the CT’s on HV and LV the currents in Diff. Protection shall measured and confirmed that the Diff current shall be zero and Restraint current shall be high.

6.4 Risk Assessment & safety precautions.

Safety measures are identified through risk assessment process as follows,

6.4.1 Risk assessment to be carried before the testing activity to identify areas of risk for both personal and equipment safety while doing the testing activity.

6.4.2 Adequate safety measures to be taken to avoid injury to persons or damages to equipment based on risk assessment.

6.4.3 Follow safety guidelines and procedures while working in substations. 6.4.4 Regarding the activity mentioned in the QP, The risk assessment & safety Precautions are identified in,

• TP/TPD/TPC-A01 – Conducting relay testing during commissioning

6.5 KPI / measurements.

KPI are identified, measured & results analysed to monitor the process/activity

and implement actions to achieve planned results and work for continual improvement.

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6.5.1 The measurement of the procedure output will be recorded in KPI sheet by

measuring the number of problems and abnormalities noticed after Energization of substation due to lapses in commissioning activities.

7.0 RECORDS

7.1 The test report shall be signed and kept in concerned file.

7.2 The relay configuration and settings file (soft copy)and signed setting template in PDF format is submitted to TPD-PCS

8.0 DISTRIBUTION

8.1 VP-TP

8.2 M-TPC

9.0 ATTACHMENTS

9.1 Final Setting Test Report Siemens 7UT612 – TP/TPD/PFS/TPC/QP-13:A01(5 pages)

9.2 Final Setting Test Report MICOM P632 - TP/TPD/PFS/TPC/QP-13:A02(4 pages)

9.3 Final Setting Test Report Duo Bias-M - TP/TPD/PFS/TPC/QP-13:A03(3 pages)

9.4 Transformer Differential Sensitivity Test Report.- TP/TPD/PFS/TPC/QP-13:A04 (7 pages)

9.5 Transformer Differential Stability Test Report.- TP/TPD/PFS/TPC/QP-13:A05(5 pages)

9.6 Risk assessment – TP/TPD/TPC-A01

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Main Contractor Name of Bay:

Consultant: Equipment:

Manufacturer SCADA No: Dt.

Final Settings Tests of DIFFERENTIAL RELAY Type: 7UT612.

RSI: ……… ELECTROSTATIC DISCHARGE (ESD)

The relay incorporate CMOS static sensitive devices, which may be damaged by static electricity discharged from the body. When handling care should be taken to avoid contact with components and electrical connections. If the relay is removed from its case for any period of time. It should be placed in an electrically conducting anti-static bag. If making measurements on the internal electronic circuitry, its preferable you are earthed to he case with a conductive strap having a resistance to ground between 500k Ohms – 10 m Ohms

REFERENCE DOCUMENT:

SIPROTEC Transformer Differential PROTECTION 7UT612: ……….………….. 1- GENERAL DATA

Ordered MLFB: Serial No.

Built in MLFB: Ordered Version: Built-in Version:

Ordered rated current IN: 1A Ordered rated auxiliary voltage (DC): 110 V DC Built-in rated current IN: 1A Built-in rated auxiliary voltage (DC): 110 V DC Software used: DIGSI 4.5/4.6

Serial interface configuration RS 232 Front Port

Substation address: Feeder address:

Relay address: Baud rate: 38400

Fault recording setting By pick-up By trip command

2- General Inspection and Testing:

i. Visual inspection ………

ii. Confirmation of unique Sr. Number on Case and inside the relay ……… iii. Correctness of installation and wiring as per approved drawings ………

iv. Confirmation of Earthing of relay case to local earth bar ………

v. Confirmation of Jumpers on A-CPU for 110- 250VDC Rated Voltage……… vi. Confirmation of Jumpers on A-I/O-3 for 1 Amp. Rated current ……… vii. Confirmation of Jumpers A-CPU for High Binary input voltage ……… CONFIGURATION OF PROTECTION FUNCTIONS

• Differential Protection Configured

• Back Up O/C Time Protection Configured

• Thermal over Load Protection Configured

• Cold Load Pick Up Configured

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RSI: ………

3- Transformer Data:

Transformer Data Primary Winding Secondary Winding

UN 132 kV 12kV

PN 50 MVA 50 MVA

IN (calculated) 218.7 A 2405.7

CT Ratio 300/1 3200/1

4- Settings of Diff. Protection:

I diff > : I/ In = t diff > delayed : I diff >> : I/ In = t diff >> delayed : 2nd. Harmonic : Slope 1: 5th. Harmonic : Slope 2: Vector Group: Base Point 1:

Base Point 2: 5- Measurements Checks:

Tested

Phases Tested Winding

Secondary Injected (A) Primary Measured (A) I diff. Measured (I/In) I Rest. Measured (I/In) R Y B Winding side 1 1.0 1.0 1.0 R Y B Winding side 2 1.0 1.0 1.0 6- Relay Pickup Values:

Test Function

Phases Tested Winding

Current (A)

Expected P/U D/O

R Side 1 Y B R Side 2 Y B 7- Timing Test: Test Function Phases Tested Winding Side 1 or Side 2 Timing Test Current Inj. (A) Expected

(mSec) Act (mSec) R

1.5 X Idiff >

38

Y 38

B 38

8- DIFFERENTIAL PROTECTION TESTING:

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RSI: ………

Phases _SettingsRelay

Current Injection on CT-1 (A) Current Injection on CT-2 (A) Expected Trip Value CT Side 1 Obtained Trip Value at Increasing current on CT Side-1 Trip Time 4 x Idiff Inj. (A) TIME (Sec) R 0.2 0.2 0.2 0.4 Y 0.2 0.2 0.2 0.4 B 0.2 0.2 0.2 0.4

7- DIFF (HIGH SET) TESTING

I Diff >> (High Set): Injected Current (A) LED Indication: ________ 8- HARMONIC BLOCK TESTING

Setting LED Indication

Harmonic Block in Red Phase 15 % ≥

Harmonic Block in Yellow Phase 15 % ≥

Harmonic Block in Blue Phase 15 % ≥

a. Testing of 2nd_{Harmonic Restraint :}

b. Testing of Cross Blocking of 2nd_Harmonics:

- Cross-blocking of Harmonics Setting: 15%

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RSI: ……… Set Cross-block time (ms) Phase Injected Current (A) Frequency/ Harmonics (Hz) Measured Cross-block time (ms)

Result with LED indication

100

R 1.0 50

Y 0.30 100

B 1.0 50

9- Testing of Add on Stabilization for External faults :

- I-ADD ON STAB setting: 3xI/In and Set duration of ADD-on stabilization: 10 Cycles. Simulate in state sequencer the saturation condition of one side CT:

Inject through fault currents (3.25 Amps) for 2 ms in state1 and then inject decreased currents through one side of relay for 2 ms in state2 while other side current is unchanged and then in state3, inject more decreased currents for time longer than blocking duration to observe trip blocking within the ADD-on stabilization period and trip release after the period is over. The relay will detect CT saturation within 5 ms after the fault incidence and saturation of CT and block trip for settable duration only.

Set duration of ADD-on stabilization (msec)

Measured duration of ADD-on stabilization (msec)

200

10- BINARY OUTPUT CONTACTS

Binary Output Terminal No. Assigned for Test Result

BO 1 F6 – F7 BO 2 F8 – F9 BO 3 F10 – F11 BO 4 F12 – F13 BO 5 F14 – F15 Watch Dog F3 – F5 F4 – F5

Note: check status of Watch Dog contacts while the relay is energized and de-energized. 10- BINARY INPUTS

Binary Output Terminal No. Assigned for Test Result

BI 1 F14 – F15 BI 2 F16 – F15 BI 3 F17 – F18 11- LEDS CHECK TP/TPD/PFS/TPC/QP-13:A01 Page 4 of 5

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RSI: ………

LEDs Assigned for Test Result

1 I Diff > Trip 2 I Diff >> Trip 3 Diff 2nd_{Harm L1/L2/L3} 4 Diff 5th Harm L1/L2/L3 5 Cross Blk by 2nd_Harm 6 Cross Blk by 5th Harm 7 Diff blk. EXT.Flt. L1/L2/L3 RESETTING OPERATION I. OTHER CHECKS:

A) Check Operation & Resetting Of All Front Panel LED's :…………

B) Trip Relay Operation And All Alarms : …………

C) DR, ER's Downloaded and print out attached/ Final setting print out attached: ………..

Testing Instruments Details

Particulars Make Type Sr.No. Cal. Due Date

Tested By (Manufacturer) Witnessed By (DEWA) Signature

Name

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Final Settings Tests of DIFFERENTIAL RELAY Type MICOM P632

RSI: ………..

ELECTROSTATIC DISCHARGE (ESD)

1- RELAY DATA

Current In Model No.

Voltage Vn SL.No.

Frequency Software Ref.

Aux. Voltage

2- GENERAL INSPECTION

Visual inspection/ Correctness of Installation and wiring

Sr.No. on module, case and cover are identical

Relay case connected to a local earth bar

Installation & wiring correct to relevant drawings

Wiring and installation checks

Check for correct voltage polarity/Record the level at rear of the relay 3- LED CHECK

Check the operation of all LED’s on the relay front panel.

LED No. Allocation Result

LRD H1 Healthy

LED H2 Out of Service

LED H3 Alarm

LED H4 Main Gen Trip Signal

LED H5 LED H6 LED H7 LED H8 LED H9 LED H10 LED H11 LED H12 LED H13 LED H14 LED H15 LED H16

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RSI: ……….. 4- OUTPUT RELAY CHECKS

Terminal No. Output Relay No. Contact Resistance_{( <0.5 Ohms)} Result

X18:2 - X18:3 K1801 X18:5 - X18:6 K1801 X18:8 - X18:9 K1802 X18:11 - X18:12 K1802 X18:14 - X18:15 K1803 X18:17 - X18:18 K1803 X18:20 - X18:21 K1804 X18:23 - X18:24 K1805 X18:26 - X18:27 K1806 X20:1 - X20:2 K2001 X20:3 - X20:4 K2001 X20:6 - X20:7 K2002 X20:8 - X20:9 K2003 X20:10 - X20:11 K2004 X20:10 - X20:12 K2005 X20:10 - X20:13 K2006 X20:10 - X20:14 K2007

Note: check status of Watch Dog contacts while the relay is energized and de-energized.

5- MEASUREMENT CHECK :

Winding HV CT ratio: ………, Winding LV CT ratio:…………..

HV Side LV Side Injected Current Amps Expected Current Amps Measured Current Amps Injected Current Amps Expected Current Amps Measured Current Amps IR IY IB

6- DIFFERENTIAL PROTECTION SETTINGS:

 HV Winding “a” Amplitude Matching Factor: Kam,a ……….

 LV Winding “b” Amplitude Matching Factor: Kam,b ………

 Vector Group referene ……….

 Zero Sequence filter on wingidng -HV “a” ……….

 Zero Sequence filter on wingidng -LV “b” ……….

 I diff > ………. M1 ……….M2 ………..

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RSI: ……….. 7- BINARY INPUTS CHECK:

Binary input No. Terminal No. Pick up Volgage Results U 2001 X20: 18 & 19

8- DIFFERENTIAL PROTECTION CHECKS:

8. a. Checking of the first section of tripping characteristics.

Test Winding Expected operating current Measured current

3-phase current injection a = (Idiff>* Inom)/Kam,a = = 3-phase current injection b = (Idiff>* Inom)/Kam,b = = 1-phase current injection (R phase) a = (Idiff>*Inom)/(Kam,a*Ks,1,a) = = 1-phase current injection (R phase) b = (Idiff>*Inom)/(Kam,b*Ks,1,b) = =

8. b. Checking of second/third section of tripping characteristic: Test method : 3 phase currents injected in winding “a” and “b”. Section of tripping char. Under test Sec. phase currents at operating point Winding “a” Sec. phase currents at operating point Winding “b” Differential current measured by relay at operating point Restrain current measured by relay at operating point Theoretical diff. current for measured restrain current Second Second Third Third 8. c. CT Saturation Checks :

Connection – YY0 2nd_{Harmonic –}_Disabled_{Zero Sequence Filter -}_Off

Phase _Current _Frequency _Current _Frequency LED Indications

IR

IY

IB

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RSI: ……….. Injected current = 1A Operating time Injected current = _1A Operating time

IR HV IR LV

IY HV IY LV

IB HV IB LV

8. e. 2 nd_{Harmonic Magnetizing Inrush Restraint Checks:}

Injected Current 1 Amp

2nd_{Harmonic inrush Block Setting} _{15 %}

Relay performance for 2nd_Harmonic content

R Phase Y Phase B Phase

BLK TRIP BLK TRIP BLK TRIP

9- HIGH SET FUNCTION CHECKS : Idiff >> Phase Setting Operating Current

expected

Operating Current (Actual)

Operating Time at Twice the Setting IR

IY

IB

10- OTHER CHECKS:

Check Operation Of All Front Panel LED's : ……….

Setting Printout taken and Confirmed with Approved Settings : ……… Fault recorder and Events Print out taken and Verified : ………

Operation of Trip Relay F94.1 Confirmed : ………

SCADA Alarms Confirmed : ………

Fault Recorder initiation Confirmed : ………

Tested By (Contractor) Witnessed By (DEWA) Signature

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Final Settings Tests of Differential Relay Type DUOBIAS-M

RELAY SETTING IDENTIFIER: ………

ELECTROSTATIC DISCHARGE (ESD)

1. GENERAL DATA

Relay Type : Model No :

In : Vx :

Serial No :

2- GENERAL INSPECTION

i) Visual inspection : __________

ii) Installation & Wiring Correct To Relevant Drawings : __________

iii) Relay Case Connected To Earth Bars : __________

iv) Insulation Resistance With 500v Megger : __________ v) Aux. Supply Connected To Correct Terminal 13 (+Ve), 14(-Ve) : __________

vi) Relay Test Block CT Shorting Proved : __________

2. SECONDARY INJECTION TEST

RELAY SETTING ADOPTED

H.V. CT RATIO :___________ L.V. CT RATIO :___________ H.V.INTERPOSING CT :___________ L.V.INTERPOSING CT :___________

CONNECTION : __________ CONNECTION :___________

MULTIPLIER : ___________ MULTIPLIER :___________

4. METERING CHECK

WINDING PHASES I-APPLIED

RELAY DISPLAY

L1 L2

RELAY CURRENT

OPERATE REST.

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5A. BIAS CHARACTERISTIC TEST BIAS SLOPE LIMIT: P H A S E S IN IT IA L S E T T IN G B IA S S E T T IN

G BIAS CURRENT (A1)

0 1 1.5 2 4

OPERATING CURRENT (A2)

MEAS. EXPT. MEAS. EXPT. MEAS EXPT MEAS EXPT MEAS EXPT

R

Y

B

5B. OPERATING TIME

RELAY SETTING

CURRENT INJECTED OPERATING TIME AT 3 X Is

R Y B R Y B

5 C. HIGHEST ELEMENT

RELAY SETTING _RCURRENT INJECTED_Y _B OPERATING TIME AT 2 X Is_B _Y _B

6. MAGNETIZING INRUSH RESTRAIN TEST:

PHASE SETTING SECOND HARMONIC CURRENT % RESULT

19 20 22 25

R 20%

Y 20%

B 20%

7. STATUS INPUT CHECKS Opto input no. Terminal No. Pickup (V) Drop Off (V) Opto input no. Terminal No. Pickup (V) Drop Off (V) S1 S7 S2 S8 S3 S9 S4 S10

(26)

S5 S11

S6

8- LED FUNCTIONAL LABEL AND OPERATION:

LED

NO. FUNCTION OPERATION LED NO. FUNCTION OPERATION

1 GENERAL TRIP 17 SPARE

2 HIGHE SET OPTD 18 SPARE

3 PHASE A TRIP 19 SPARE

4 PHASE B TRIP 20 SPARE

5 PHASE C TRIP 21 SPARE

6 NEW DATA STORED 22 SPARE

7 SPARE 23 SPARE 8 SPARE 24 SPARE 9 SPARE 25 SPARE 10 SPARE 26 SPARE 11 SPARE 27 SPARE 12 SPARE 28 SPARE 13 SPARE 29 SPARE 14 SPARE 30 SPARE 15 SPARE 31 SPARE 16 SPARE 32 SPARE

9. OUTPUT RELAY CHECK

Opto input

no. Terminal No.

Contact

Resistance Result input Opto no. Terminal No. Contact Resistance Result RL1 RL8 RL2 RL9 RL3 RL10 RL4 RL11 RL5 RL12 RL6 RL13 RL7

Note: check status of Watch Dog contacts while the relay is energized and de-energized.

10- OTHER CHECKS:

1. Trip relay operation, protection operated signal verified in SCS and FRP : ……….

2. Disturbance Recorder and Events printout attached : ………. 3. Date and time set in the relay/ Final setting printout attached with test format : ……….

Testing Instrument Details

Particulars Make Type Sr. No. Cal. Due Date

(27)

Signature Name

(28)

CONTRACT NO: NAME OF SUB STATION:

IDT Differential PROTECTION SENSITIVITY TESTS RELAY SETTING

I-DIFF > Setting : I/Inob I-DIFF >> Setting : I/Inob Calculated I POC : Amps

Slope 1 : Slope-2 :

Base point 1 : Base Point-2 :

CT

Ratio InjectedPhases

Primary Current

(Amps) Enter details of measured current in mA at Relay Panel

T R . D IF F & R E F 3 00 /1 ( 13 2 K V T 1. 1 S ID E ) B U S -1

XA (mA) X87 (mA) X64 (mA)

1 2 3 4 21₂₂ 23₂₄ 25₂₆ 27₂₈ 25₂₆ 27₂₈ R – E

Y – E B – E

Relay Display Relay Current (mA)

HV (A) LV (kA) HV LV

R Y B R Y B Q1 Q3 Q5 Q6 R1 R3 R5 R6

R – E Y – E B – E

Rest Current (IN) Oper. Current (IN) Led Indication

Relay Display Relay Display _{Relay Display}

R Y B R Y B

R – E Y – E B – E

SEQ (HV) (A) SEQ (LV) (kA)

I1 I2 3I0 I1 I2 3I0

R – E Y – E B – E

(29)

IDT Differential PROTECTION SENSITIVITY TESTS

CT

Ratio InjectedPhases

Primary Current

XA (mA) X87 (mA) X64 (μA)

1 2 3 4 21₂₂ 23₂₄ 25₂₆ 27₂₈ ₂₆25 ₂₈27 R – Y

Y – B B – R

R – Y Y – B B – R

Relay Display Relay Display _{Relay Display}

R Y B R Y B

R – Y Y – B B – R

I1 I2 3I0 I1 I2 3I0

R – Y Y – B B – R

(30)

CT Ratio

Phases Injected

Primary

Current (A) Enter details of measured current in mA at Relay Panel

XA (mA) X87 (mA) X64 (mA)

1 2 3 4 21₂₂ 23₂₄ 25₂₆ 27₂₈ 25₂₆ 27₂₈

R – E Y – E B – E

Relay Display Relay Display

Relay Display

R Y B R Y B

R – E Y – E B – E

I1 I2 3I0 I1 I2 3I0

R – E Y – E B – E

(31)

CT Ratio Phases Injected Primary Current

XA (mA) X87 (mA) X64 (μA)

1 2 3 4 21₂₂ 23₂₄ 25₂₆ 27₂₈ 25₂₆ 27₂₈

R – Y Y – B B – R

RELAY DISPLAY RELAY DISPLAY _{Relay Display}

R Y B R Y B

R – Y Y – B B – R

I1 I2 3I0 I1 I2 3I0

R – Y Y – B B – R

(32)

CT Ratio Phases Injected Primary Current (Amps)

Enter details of measured current in mA at Relay Panel

T R . D IF F & R E F 3 20 0/ 1 ( 11 K V S ID E )

XA (mA) X87 (mA) X64 (mA) (11KV)

9 10 11 12 5₆ 7₈ ₁₀9 11₁₂ 25₂₆ 27₂₈

R – E Y – E B – E

Relay Display Relay Display _{Relay display}

R Y B R Y B

R – E Y – E B – E

I1 I2 3I0 I1 I2 3I0

R – E Y – E B – E

(33)

CT Ratio Phases Injected Primary Current

T R . D IF F & R E F 3 20 0/ 1 ( 11 K V S ID E )

XA (mA) X87 (mA) X64 (μA) (11KV)

9 10 11 12 5₆ 7₈ ₁₀9 11₁₂ 25₂₆ 27₂₈

R – Y Y – B B – R

Relay Display Relay Display

Relay Display

R Y B R Y B

R – Y Y – B B – R

I1 I2 3I0 I1 I2 3I0

R – Y Y – B B – R

(34)

(35)

IDT Differential PROTECTION STEBILITY TESTS

RELAY SETTING

I-DIFF > Setting : I/Inob I-DIFF >> Setting : I/Inob Calculated I POC : Amps

Slope 1 : Slope-2 :

Base point 1 : Base Point-2 :

APPLIED VOLTAGE AT LV SIDE [WHILE HV SIDE SHORTED]: RY:……….., YB:……… , BR:……….

132KV BUS-1 CT : NORMAL 11KV CT : NORMAL

Tap position: 1 Tap position: 10 Tap position: 19

R Y B N R Y B N R Y B N Primary Current 11 KV (A) --- --- ---Secondary current 132 KV (F87T) mA 11 KV (F87T) mA Relay Display Line current (H.V) (A) --- --- ---Line current (L.V) (KA) --- --- ---Differential current --- --- ---Restraining current --- --- ---HV REF Relay current (mA) Operation LV REF Relay current (mA) Operation CT RATIO: 132 KV : 300/1A 11 KV : 3200/1A

(36)

132 Reversal

132KV BUS-1 CT : REVERSE 11KV CT : NORMAL

Tap position: 10

R - REVERSE Tap position: 10Y- REVERSE Tap position: 10B - REVERSE

R Y B N R Y B N R Y B N Primary Current 11 KV (A) --- --- ---Secondary current 132 KV (F87T) mA 11 KV (F87T) mA Relay Display Line current (H.V) (A) --- --- ---Line current (L.V) (KA) --- --- ---Differential current --- --- ---Restraining current --- --- ---HV REF Relay current (mA) Operation LV REF Relay current (mA) Operation 132KV BUS-2 CT : NORMAL 11KV CT : NORMAL

Tap position: 1 Tap position: 10 Tap position: 19

R Y B N R Y B N R Y B N Primary Current 11 KV (A) --- --- ---Secondary current 132 KV (F87T) mA 11 KV (f87T) mA Relay Display Line current (H.V) (A) --- --- ---Line current (L.V) (KA) --- --- ---Differential current --- --- ---Restraining current --- --- ---HV REF Relay current (mA) Operation LV REF Relay current (mA) Operation

(37)

132KV BUS-2 CT : REVERSE 11KV CT : NORMAL

Tap position: 10

R Y B N R Y B N R Y B N Primary Current 11 KV (A) --- --- ---Secondary current 132 KV (F87T) mA 11 KV (F87T) mA Relay Display Line current (H.V) (A) --- --- ---Line current (L.V) (KA) --- --- ---Differential current --- --- ---Restraining current --- ---

---HV REF Relay current (mA) Operation LV REF Relay current (mA) Operation 11kV Reversal 132KV BUS-1 CT : NORMAL 11KV CT : REVERSE Tap position: 10 R - REVERSE Tap position: 10 Y- REVERSE Tap position: 10 B - REVERSE R Y B N R Y B N R Y B N Primary Current 11 KV (A) --- --- ---Secondary current 132 KV (F87T) mA 11 KV (F87T) mA Relay Display Line current (H.V) (A) --- --- ---Line current (L.V) (KA) --- --- ---Differential current --- --- ---Restraining current --- --- ---HV REF Relay current (mA) Operation LV REF Relay current (mA) Operation

(38)

132KV BUS-2 CT : NORMAL 11KV CT : REVERSE

Tap position: 10

R Y B N R Y B N R Y B N Primary Current 11 KV (A) --- --- ---Secondary current 132 KV (F87T) mA 11 KV (F87T) mA Relay Display Line current (H.V) (A) --- --- ---Line current (L.V) (KA) --- --- ---Differential current --- --- ---Restraining current --- --- ---HV REF Relay current (mA) Operation LV REF Relay current (mA) Operation Normalising 132KV BUS-1 CT : NORMAL 11KV CT : NORMAL TAP POSISTION: 10 R Y B N Primary Current 11 KV (A) ---Secondary current 132 KV (F87T) mA 11 KV (F87T) mA Relay Display Line current (H.V) (A) ---Line current (L.V) (KA) ---Differential current ---Restraining current ---HV REF Relay current (mA) Operation LV REF Relay current (mA) Operation

(39)

132KV BUS-2 CT : NORMAL 11KV CT : NORMAL TAP POSISTION: 10 R Y B N Primary Current 11 KV (A) ---Secondary current 132 KV (F87T) mA 11 KV (F87T) mA Relay Display Line current (H.V) (A) ---Line current (L.V) (KA) ---Differential current ---Restraining current ---HV REF Relay current (mA) Operation LV REF Relay current (mA) Operation