BE1-951
Testing and Maintenance
13-31
Step 5
With three-phase voltage still applied, increase the A-phase current until OUT1 closes. Swing the
angle of the applied c90 degrees and -90 degrees away from the 80-degree positive
sequence line angle. Verify that OUT1 opens at approximately 170 degrees I lag E and 350
degrees I lag E. Out1 should remain closed from 170 through 80 to 350 degrees I lag E (defined
as forward trip direction)
Negative Sequence Voltage Polarizing, Phase Overcurrent Elements
Step 6
Apply a 120 Vac, three-phase voltage source at nominal frequency to terminals C13 (A-phase),
C14 (B-phase), C15 (C-phase) and C16 (Neutral). Reduce the A-phase voltage by 1/3. Transmit
M-V command or view HMI screen 3.4 to verify that negative sequence voltage is greater than 1
volt.
Step 7
Apply 0 amp A-phase current at an angle of 80 degrees I lag E (same as positive sequence line
angle) and slowly increase the current until OUT1 closes. Decrease A-phase current until OUT1
just drops out. Pickup will occur 2 percent of the 50TP pickup setting. Dropout will occur
at 93 to 97% of actual pickup. Verify 67A target on the HMI.
Step 8
With the same voltage still applied, increase the A-phase current until OUT1 closes. Swing the
angle of the applied c90 degrees and -90 degrees away from the 80-degree positive
sequence line angle. Verify that OUT1 opens at approximately 170 degrees I lag E and 350
degrees I lag E. Out1 should remain closed from 170 through 80 to 350 degrees I lag E (defined
as forward trip direction)
Negative Sequence Voltage Polarizing, Negative Sequence Overcurrent Elements
Step 9
Using Table 13-36 as a guide, transmit the 67 setting commands to the relay.
Table 13-36. 67P-50TQ Operational Settings
Operating Settings
Purpose
S0-50TP=0,0,F
Sets 50TP at 0 amps, 0 time delay, Forward Tripping Direction
S0-50TN=0,0,F
Sets 50TN at 0 amps, 0 time delay, Forward Tripping Direction
S0-50TQ=0.5,0,F
Sets 50TN at 0.5 amps, 0 time delay, Forward Tripping Direction
Step 10 Apply a 120 Vac, three-phase voltage source at nominal frequency to terminals C13 (A-phase),
C14 (B-phase), C15 (C-phase) and C16 (Neutral). Reduce the A-phase voltage by 1/3. Transmit
M-V command or view HMI screen 3.4 to verify that negative sequence voltage is greater than 1
volt.
Step 11 Apply 0 amp A-phase current at an angle of 80 degrees I lag E (same as positive sequence line
angle) and slowly increase the current until OUT3 closes (Negative Sequence Pickup current will
be approximately 1/3 the applied A-phase current value). Decrease A-phase current until OUT3
just drops out. Pickup will occur 2 percent of the 50TQ pickup setting. Dropout will occur
at 93 to 97% of actual pickup. Verify the 67Q target on the HMI.
Step 12 With the same voltage still applied, increase the A-phase current until OUT3 closes. Swing the
angle of the applied c90 degrees and -90 degrees away from the 80-degree positive
sequence line angle. Verify that OUT3 opens at approximately 170 degrees I lag E and 350
degrees I lag E. OUT3 should remain closed from 170 through 80 to 350 degrees I lag E (defined
as forward trip direction)
Step 13 (Optional) Repeat steps 3 through 12 for B-phase current (D3 and D4) and C-phase current (D5
and D6). Reduce the corresponding B-phase and C-phase voltage for negative sequence tests.
