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7 TESTING
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
timing accuracy. Pre-trip values may be viewed by pressing
Table 7–18: SHORT CIRCUIT TIMING
INJECTED CURRENT
5 A UNIT
30 A
40 A
50 A
GE Power Management
EXPECTED TIME
TO TRIP
1 A UNIT
6 A
< 50 ms
8 A
< 50 ms
10 A
< 50 ms
469 Motor Management Relay
7.3 ADDITIONAL FUNCTIONAL TESTING
7.3.5 SHORT CIRCUIT TEST
RESET
NEXT
after each trip.
MEASURED TIME
TO TRIP
key, and verify
7
7-13
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