DJ tripping without any apparent cause (TWAC)
ABNORMAL SIGN:
DJ tripping during coasting or progression/regression
CAUSES:
1. Action of safety relays without target
2. Pantograph not making contact with OHE at times
3. Poor contact of fuses CCPT,CCDJ,CCA
4. Sluggish operation of SMGR
5. Chattering of relays Q118 and Q44
6. Loose contact of BL switch interlocks
Troubleshooting
a) Gently tap the safety relays. If all relays are normal, place HQOA on 0, HQOP1 & HQOP2 and HOBA in OFF position. If successful, resume traction with precautions. b) Change the pantograph and try. c) Check the fuses CCPT, CCDJ & CCA for any slackness or rise in temperature. If so change the fuse and resume traction.
d) Ensure SMGR pressure 2.5-3.5Kg/cm² and try to work by notch by notch progression/ regression. If unsuccessful, clear section by manual control of GR with 40 Kmph and contact TLC
e) If unsuccessful, wedge Q118 in energized condition and resume traction with precautions.
f) For Q44 chattering Place HVSI 1 and HVSI 2 in 3 position and try.
g) If unsuccessful, normalize all the above switch position, lock and unlock BL and try if unsuccessful, change the cab and clear section by rear cab driving.
h) If unsuccessful contact TLC.
ABNORMAL SIGN:
DJ tripping during coasting or progression/regression
CAUSES:
1. Action of safety relays without target
2. Pantograph not making contact with OHE at times
3. Poor contact of fuses CCPT,CCDJ,CCA
4. Sluggish operation of SMGR
5. Chattering of relays Q118 and Q44
6. Loose contact of BL switch interlocks
Troubleshooting
a) Gently tap the safety relays. If all relays are normal, place HQOA on 0, HQOP1 & HQOP2 and HOBA in OFF position. If successful, resume traction with precautions. b) Change the pantograph and try. c) Check the fuses CCPT, CCDJ & CCA for any slackness or rise in temperature. If so change the fuse and resume traction.
d) Ensure SMGR pressure 2.5-3.5Kg/cm² and try to work by notch by notch progression/ regression. If unsuccessful, clear section by manual control of GR with 40 Kmph and contact TLC
e) If unsuccessful, wedge Q118 in energized condition and resume traction with precautions.
f) For Q44 chattering Place HVSI 1 and HVSI 2 in 3 position and try.
g) If unsuccessful, normalize all the above switch position, lock and unlock BL and try if unsuccessful, change the cab and clear section by rear cab driving.
h) If unsuccessful contact TLC.
