GENERAL DATA & INFORMATION Bay No. Bay Name Relay designation LINE DIFF. No. 0411L1x6x1C7CCxH5C424xx Make S. No. Rated Current 1A Rated Voltage 66.4 V L-N AC Frequency 50/60 HZ Logic inputs 125VDC Aux. Voltage 125/250V AC/DC Comm. Interface CH-X IEEEC37.94, 850nm Fiber Comm. Interface CH-Y IEEEC37.94, 850nm Fiber MECHANICAL CHECKS AND VISUAL INSPECTION Sl.no General checks Status 1. Inspect for no physical damage. 2. Verify the wiring connection as per approved drawing. 3. case connected to a local earth bar. 4. Power up the relay circuit and check relay is healthy. 5. Set the relay internal clock. 6. Send the relay setting configuration file to relay through Port F. WATCHDOG CHECK: Check status of watchdog contacts as below. OUTPUT Contact Status Remarks Relay De- energized Energized C28-C29 CLOSE OPEN DC BURDEN CHECK: Relay Status V Aux Applied(V) I Measured (mA) Expected Watts Calculated Watts Enabled 125 <25W Enabled & Trip 125 <25W
Note: Open 5025 HMI view after connecting to the relay. “Local Instantaneous metering” view and save the snapshot in to annexure word document. Click “phasor” view and save the snapshot in to annexure word document. Find the “Report annexure section.2” for relay Measurement report. Voltage Applied: 3PH, 115V AC Current applied: 3PH, 1.0A PTR: 380KV/115V CTR: 3000/1A CURRENT MEASUREMENT: Local PHASE A MAG/ ANG PHASE B MAG/ ANG PHASE C MAG/ ANG 3I0 MAG/ ANG 3I2 MAG/ ANG I1 MAG/ ANG Expected Actual Local PHASE A MAG/ ANG PHASE B MAG/ ANG PHASE C MAG/ ANG 3I0 MAG/ ANG 3I2 MAG/ ANG I1 MAG/ ANG Expected Actual
Local A MAG/ ANG B MAG/ ANG PHASE C MAG/ ANG 3I0 MAG/ ANG 3I2 MAG/ ANG I1 MAG/ ANG Expected Actual VOLTAGE MEASUREMENT: Local PHASE AN MAG/ ANG BN MAG/ ANG PHASE CN MAG/ ANG Expected Actual
CURRENT DIFFFERENTIAL: pick up A Phase B Phase C P/U (A) HMI Idiff = IAT (secA) D/O (A) P/U (A) HMI Idiff = IBT (sec A) D/O (A) P/U (A) HMI Idiff = ICT (sec A) D/O (A) Pick up Accuracy: ±3% ±0.01 INOM, According to the Catalogue for manual # 20130311 Page 56 pick up 87LPP Phase A B C P/U (A) HMI Idiff = IAT (secA) D/O (A) P/U (A) HMI Idiff = IBT (sec A) D/O (A) P/U (A) HMI Idiff = ICT (sec A) D/O (A) NEGATIVE/ ZERO SEQ CURRENT DIFFERENTIAL: 87L2P/ 87LGP Expected pick up 87L2P or 87LGP 87L2 –Negative seq diff 87LG- zero seq diff P/U (A) HMI display Idiff= 3I2T (pri A) D/O (A) P/U (A) HMI display Idiff= 3I0T (Pri A) D/O (A) Note: For 87L2 /87LG sensitivity a single current shall be injected. In this case the negative sequence (I2) or zero sequence (I0) current is equal to 1/3* Iph. But the relay compares 3 x I2_injected and 3 x I0_injected with the 87L2P / 87LGP thresholds. TIMING TEST: SETTING: A 87L2P: A 87LGP: A
Setting 87LANG=195deg, Restraining angle = 180 to 82.5 deg, Operating angle = 82.5deg to 0deg Accuracy: +/- 3deg . ALPHA RADIUS TEST: SETTING: 87LPP: 0.2 A 87L2P: 0.1A 87LGP: 0.1A 87LR:2 87LANG:195 DEG local and remote current out of phase and equal magnitude. Increase the remote current magnitude by fixing current until the relay trip to find the outer radius Increase the current magnitude by fixing remote current until the relay trip to find the outer radius. ALPHA RADIUS MEASURED AT ALPHA ANGLE =180deg. Diff. element RADIUS ODPERATION RADIUS OPERATION I Local (fixed)A I Remote(A) Radius(IL/IR) I Remote (fixed) A I Local (A) Radius (IL/IR) Operate Operate 87LA 87LB