Precautions after coupling a dead loco

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  1. Make the loco electrically dead by keeping BL, ZPT and HBA in off position.
  2. Keep both the reversers in neutral positions.
  3. Couple the dead loco mechanically (CBC?) behind the working loco.
  4. Keep A-9 (load brake) and SA-9 (loco independent brake) in the released position in both the cabs of the dead loco.
  5. Cut-out cock (A-15) of A-9 and SA-9 in both the cabs of the dead loco should be closed.
  6. Close the MTP and L&T (Brake Pipe Charging cock) of the dead loco.
  7. Keep MU2B of the dead loco in a dead or trail position.
  8. Completely drain the MR (Main Reservoir) of the dead loco and close the drain cock
  9. If the loco brakes of the dead loco are not in the released position, carry out the following steps.
    • Manually release the control pressure of the DV by release handle. This will cause the pressure to vent automatically and will release the brakes.
    • In brake cylinder line, if the brake cylinder pressure still persists, then in that case isolate the bogie isolating cock in both the bogies and wait for the BC pressure to be released before normalizing the bogie isolating cock again.
  10. Join the BP pipe of both the locos and open the BP angle cock of the working and the dead loco. Through the C-3W DV of the dead loco, the MR-4 of the dead loco will charge through the BP supply. Check the BP gauge of the dead loco. It should be in proportion with that of the working loco. If the locos to be coupled have twin pipe wherein both BP and FP pipes are present, in that case join the FP pipes and open the angle cock.
  11. If in both the locos, MR and BC equalizing pipes are present, in that case open their angle cock as done in the MU case.
Material provided by Sachin Buddhisagar, Copyright © 2008.
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