GE 750, Instruction Manual

Page: 425 / 504

GE Power Management 750/760 Feeder Management Relay 17-
19
17 COMMISSIONING 17.6 METERING
17
17.6.10 MEASUREMENT OF APPARENT POWER DEMAND
Test Connections per Figure 17–1: RELAY TEST WIRING – WYE CONNECTION or Figure 17–2: RELAY
TEST WIRING – DELTA CONNECTION on page 17–4.
Expected Accuracy: ± 2.0% of full scale
Actual Values Displays:
Under subheading
A2 METERING \ DEMAND \ APPARENT POWER \
LAST APPARENT POWER DEMAND
MAX APPARENT POWER DEMAND (DATE, TIME)
Procedure:
Follow the procedure in Section 17.6.7: MEASUREMENT OF CURRENT DEMAND on page 17–17, except
that the injected and monitored parameter is VA.
17.6.11 CALCULATION OF PERCENT OF LOAD-TO-TRIP
Test Connections per Figure 17–1: RELAY TEST WIRING – WYE CONNECTION or Figure 17–2: RELAY
TEST WIRING – DELTA CONNECTION on page 17–4.
Expected Accuracy: equivalent to that of phase current inputs
Actual Values Displays:
Under subheading
A2 METERING \ CURRENT \
% OF LOAD-TO-TRIP
Note:
Percent of load-to-trip is calculated from the phase with the highest current reading. It is the ratio of this current
to the lowest pickup setting among the phase time and instantaneous overcurrent protection features. If all of
these features are disabled, the value displayed will be 0.
Procedure:
Inject current of various values into phase A. Check that percent load-to-trip is calculated as the correct per-
centage of the most sensitive operational phase O/C element and displayed. Repeat for phases B and C.