
MEP 660 - Trouble shooting Manual
Doc No.: IM – 51
Rev.2.0
Print: October 2008
215
PARAMETER
DESCRIPTION
FAULT CODE
1206
FAULT MESSAGE GF Stuck Closed. Run Auto/Manual Test
RESTRICTIONS
None
ALARM BELL
--
RESET LEVEL
Low, Manual
If the fault condition is still present when cleared manually, the fault
will be generated again.
FAULT
RECOVERY
Automatic when the GF auxiliary contact found open.
PROBABLE
CAUSES
1. Defective GF contactor or aux. Contacts.
2. Defective wiring.
3. Defective digital output cards MLSD16 in slot No. 14 & 15.
FAULT
ISOLATION
1. Shut down the engine. Switch ON MB1, MB2, MPCB, MFPB1, and
MFPB2 circuit breakers. Check the status of the GF contactor.
2. If GF contactor is in energized position, check the voltage across
the GF contactor operating coil terminals.
A. If the voltage is zero, the contactor is defective. Replace the
contactor.
B. If the voltage is more than 65V, MLSD16 in slot No. 14 and in
slot 15 is defective. Replace the cards 1 by 1 and check up.
3. If GF Contactor is in de-energised position, check the status of the
Green LED 0 on the digital input card MDIP16 in slot 11 and Green
LED 1 on the digital input card MDIP16 in slot 12.
A. If any of the above green LEDs is glowing, disconnect the wire
GFFB1 & 2 wires from the GF contactor Aux. Contact. Check the
status of the Green LEDs.
a) If the Green LED is still glowing, the wire GFFB1/GFFB2
is/are shorted with some positive wire in the bunch. Identify
and remove the short circuit.
b) If the Green LED is OFF, then the GF aux. Contact is welded.
Replace the GF contactor.
4. Run self test for the GF contactor to ensure proper feed back signal
under ‘Auto test for relays’ in the ‘Test Mode’ menu available in
main menu.