Zero Sequence Overvoltage Unit, Low Level (59 Nl); Breaker Maintenance - GE SMOR-B GEK 105593C Instructions Manual

27/'59 Functions Settings Group
59NH Pick up
Time Delay 59NH
• Apply on phase A of the relay 2.7 Vac and check that the relay does not trip.
• Apply 3.3 Vac and check that the relay trips.
• Check that for this trip, the operating time is in between 0.18 and 0.22 sec.
• Set the relay as follows:
27/'59 Functions Settings Group
59NH Pick up
Time Delay 59NH
• Apply on phase A of the relay 95 Vac and check that the relay does not trip.
• Apply 105 Vac and check that the relay trips.
• Check that for this trip, the operating time is in between 3.9 and 4.1 sec.

6.25. ZERO SEQUENCE OVERVOLTAGE UNIT, LOW LEVEL (59 NL)

• Enable only 59NL function and its related trip.
• Set the relay as follows:
27/'59 Functions Settings Group
59NL Pick up
Time Delay 59NL
• Apply on phase A of the relay 2.7 Vac and check that the relay does not trip.
• Apply 3.3 Vac and check that the relay trips.
• Check that for this trip, the operating time is in between 0.18 and 0.22 sec.
• Set the relay as follows:
27/'59 Functions Settings Group
59NL Pick up
Time Delay 59NL
• Apply on phase A of the relay 95 Vac and check that the relay does not trip.
• Apply 105 Vac and check that the relay trips.
• Check that for this trip, the operating time is in between 3.9 and 4.1 sec.

6.26. BREAKER MAINTENANCE

• Set the relay as follows :
Breaker Settings Group
KI2T Operation Mode
KI2T Integration Time
• Reset all the counters on the relay.
• Enable 50PL function and its related trip. Set its pick up and time delay to the minimum possible.
• Force 2 trips, one below the nominal current and one above :
Trip-1 : 0.8 x In (phase) flowing through phases A, B and C.
Trip-2 : 1.2 x In (phase) flowing through phases A, B and C.
GEK-105593C
3 V
0.20 sec
100 V
4.0 sec
3 V
0.20 sec
100 V
4.0 sec
FIXED
0.1 sec
60