
MEP 660 - Trouble shooting Manual
Doc No.: IM – 51
Rev.2.0
Print: October 2008
69
PARAMETER
DESCRIPTION
FAULT CODE
1068
FAULT MESSAGE REV Stuck in Reverse. Run Auto/Manual Test
RESTRICTIONS
Forward Motoring and Forward Dynamic Brake Prohibited
ALARM BELL
30 seconds
RESET LEVEL
Low, Manual
After manual reset if the fault still present, the fault will be generated
again.
FAULT
RECOVERY
Automatic when the RVFFB and RVRFB feed back signals become
normal.
PROBABLE
CAUSES
1. Control air pressure is < 2Kg./Sq.Cm.
2. The REV is physically got stuck due to mechanical obstruction.
3. Defective wiring of REV feed back signals RVFFB and RVRFB
4. Defective digital input card.
5. REV forward direction magnet valve defective.
6. REV forward direction magnet valve is not getting electrical supply.
7. Defective digital output card.
FAULT
ISOLATION
1. Check and adjust the control air pressure to 5 Kg./Sq.Cm.
2. Manually operate the Reverser by pressing the forward and reverse
magnet valves alternatively to ensure free operation of the
contacts.
A. Ensure that change over contacts and auxiliary contacts are
changing their position freely.
B. If the operation of the REV is sluggish / not operating, attend /
replace the reverser.
C. Check the status of the corresponding feed back LEDs (14 & 15)
on the digital input card in slot 10. Both Green and Yellow LEDs
should toggle their status with respect to REV operation.
D. If the status is not syncronysing to REV operation:
a) Adjust the feedback auxiliary contacts to get correct logic.
b) If both Green LEDs (14 & 15) are not glowing, check the
incoming supply at the common terminal of the Aux. Contacts.
(wire No. 51) with respect to locomotive 4 wire.
c) If the supply is zero, check the continuity of 51wire loop. If
necessary change the wiring.
d) If supply is more than 65V, check the supply at out going
terminals (wire nos. RVFFB and RVRFB).
e) If supply is more than 65V on the corresponding terminal with
respective REV position
1) Check the slackness of the connector of cable ID: AU. If
slack tighten the connector.
2) Check the wire continuity of wires from REV feed back
auxiliary contacts to MEP-660. (Cable ID: AU, Pins – R &
S). If necessary replace the cable.
f) If only Green LEDs (14 & 15) are toggling their status and
corresponding Yellow LEDs are not toggling, then Digital input
card in slot 10 is defective. Replace the card.
3. Manually set the REV in Reverse direction.
4. Set the display mode to ‘Manual Test for outputs’ under Test Mode
menu.
5. Enter 11 and press ‘Enter’ key to test reverser forward.
6. Press 1 to energise the REV forward side magnet valve.