RFL 9300 RFL Electronics Inc.
October 20, 2004 8 - 13 (973) 334-3100
2. Connect a double-pole switch in the test current circuit.
This will provide a "timer-start" contact for trip time measurements. Use any
spare trip contact for "timer-stop," such as terminals 5-6 or 7-8 on TB-3.
3. Connect a dc circuit with 0.2-ampere loading in series with the TRIP 1 tripping contacts (TB3-1
and TB3-2).
4. Gradually increase the test current.
At 0.5 ampere, the ground fault detector will operate. At 0.75 ampere, the relay
will trip, and the G and TRIP-1 indicators on the 93B DISPLAY module will light.
At this point, the following conditions occur:
1. With a test current of 0.75 amperes to 1.0 amperes, the "arithmetic sum"
(or differential current) exceeds the ground bias setting of 1.5 amperes.
2. The ground fault detector will operate. This satisfies the fault detector re-
quirements for ground fault tripping.
3. The 93B PC module monitoring Phase A does not trip for two reasons:
a. There was no Phase A fault detector operation.
b. The phase bias setting is 3 amperes, which is well above the
arithmetic sum of 1.5 amperes.
5. Remove the test current. The indicators may be reset by pressing the RESET switch on the 93B
DISPLAY module.
If the 0.2-Adc trip current remains for more than 500 ms, the message "ALARM
27" will appear on the display. This means a breaker or auxiliary trip device is de-
fective.
6. Repeat steps 4 and 5 with the breaker trip circuit unloaded.
The TRIP 1 indicator will not light because the 0.2-ampere dc trip current was
never sensed. For this condition, the tripping relay remains operated for 100 ms
after the fault is removed, and the phase controller rescinds its trip signal.
7. Again starting from zero, gradually increase the current.
At 0.5 ampere, the ground fault detector will operate. At 0.75 ampere to 1.0 am-
pere, the relay will trip, and the G and TRIP-1 indicators on the 93B DISPLAY
module will light.
8. Continue to increase the current gradually.
At 1.5 amperes to 1.75 amperes, several alarms will appear:
a. The red SYS indicator on the 93B SV module will light.
b. The red alarm indicator on the 93B Phase A Controller module will light.
c. The message "ALARM 34 31 61" will appear on the display.
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