13-32
Testing and Maintenance
BE1-951
Negative Sequence Voltage Polarizing, Ground Overcurrent Elements
Step 14 Using Table 13-37 as a guide, transmit the 67 setting commands to the relay.
Table 13-37. 67N (Q pol)-50TN Operational Settings
Operating Settings
Purpose
S0-50TP=0,0,F
Sets 50TP at 0 amps, 0 time delay, Forward
Tripping Direction
S0-50TN=2.0,0,F
Sets 50TN at 2.0 amps, 0 time delay, Forward
Tripping Direction
S0-50TQ=0,0,F
Sets 50TN at 0 amps, 0 time delay, Forward
Tripping Direction
Step 15 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 16 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 OUT2 closes. Decrease A-phase current until OUT2
just drops out. Pickup will occur 2 percent of the 50TN pickup setting. Dropout will occur
at 93 to 97% of actual pickup. Verify the 67N target on the HMI.
Step 17 With the same voltage still applied, increase the A-phase current until OUT2 closes. Swing the
angle of the applied c90 degrees and -90 degrees away from the 80-degree positive
sequence line angle. Verify that OUT2 opens at approximately 170 degrees I lag E and 350
degrees I lag E. OUT2 should remain closed from 170 through 80 to 350 degrees I lag E (defined
as forward trip direction)
Zero Sequence Voltage Polarizing, Ground Overcurrent Elements
Step 18 Using Table 13-38 as a guide, transmit the 67 setting commands to the relay.
Table 13-38. 67N (Vo pol)-50TN Operational Settings
Operating Settings
Purpose
S0-67=V, VOIN
Sets 67N to Zero Sequence Voltage Polarizing. Ref
quantity = calculated V0, op quantity = calculated IN
S0-50TP=0,0,F
Sets 50TP at 0 amps, 0 time delay, Forward Tripping
Direction
S0-50TN=2.0,0,F
Sets 50TN at 2.0 amps, 0 time delay, Forward
Tripping Direction
S0-50TQ=0,0,F
Sets 50TN at 0 amps, 0 time delay, Forward Tripping
Direction
Step 19 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 the zero sequence voltage is greater than 1
volt.
Step 20 Apply 0 amp A-phase current at an angle of 80 degrees I lag E (zero sequence line angle) and
slowly increase the current until OUT2 closes. Decrease A-phase current until OUT2 just drops
out. Pickup will occur 2 percent of the 50TN pickup setting. Dropout will occur at 93 to 97%
of actual pickup. Verify the 67N target on the HMI.