GE 469

GE Power Management 469 Motor Management Relay 7-13
7 TESTING 7.3 ADDITIONAL FUNCTIONAL TESTING
7
7.3.5 SHORT CIRCUIT TEST
The 469 specification for short circuit timing is +50 ms. The pickup accuracy is as per the phase current inputs.
Perform the steps below to verify the performance of the short circuit element.
1. Alter the following setpoints:
S2 SYSTEM SETUP\CURRENT SENSING\PHASE CT PRIMARY: 1000
S6 CURRENT ELEMENTS\SHORT CIRCUIT TRIP\SHORT CIRCUIT TRIP: On
S6 CURRENT ELEMENTS\SHORT CIRCUIT TRIP\ASSIGN TRIP RELAYS: Trip
S6 CURRENT ELEMENTS\SHORT CIRCUIT TRIP\SHORT CIRCUIT TRIP PICKUP: 5.0
×
CT
S6 CURRENT ELEMENTS\SHORT CIRCUIT TRIP\INTENTIONAL S/C DELAY: 0
2. Inject current as per the table below, resetting the unit after each trip by pressing the key, and verify
timing accuracy. Pre-trip values may be viewed by pressing after each trip.
Table 7–18: SHORT CIRCUIT TIMING
INJECTED CURRENT EXPECTED TIME
TO TRIP
MEASURED TIME
TO TRIP
5 A UNIT 1 A UNIT
30 A 6 A < 50 ms
40 A 8 A < 50 ms
50 A 10 A < 50 ms
RESET
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