Electric engines and MU under overhead wires must be considered energized (Live) except?

Electric engines and MU under overhead wires must be considered energized (Live) except?

• A. When it is known that all Pantographs are down and Pantograph grounding switches are closed, or overhead wires are de-energized, tested de-energized and properly grounded
• B. When the pantographs are up
• C. When the train is stopped
• D. When the crew has a permit

Answer: (A)

Electric locomotives and MU cars under overhead wires present a real risk of shock or arcing because the overhead system is a high-voltage power source. The safe rule is to treat the equipment as energized until you have verified it is truly de-energized and bonded to ground. The only situation that allows working as not energized is when all contact with the wire is removed and a verified de-energization process is in place: pantographs are down and the pantograph grounding switches are closed, or the overhead wires are de-energized, tested de-energized, and properly grounded. In that state there is no electrical energy available to the equipment, so it’s safe to work. If the pantographs are up, there could still be voltage present and a path for current. Merely stopping the train doesn't change the electrical status of the lines. Having a permit alone doesn’t guarantee that power is actually de-energized and grounded; verification and grounding are required to remove the live condition.

Electric locomotives and MU cars under overhead wires present a real risk of shock or arcing because the overhead system is a high-voltage power source. The safe rule is to treat the equipment as energized until you have verified it is truly de-energized and bonded to ground. The only situation that allows working as not energized is when all contact with the wire is removed and a verified de-energization process is in place: pantographs are down and the pantograph grounding switches are closed, or the overhead wires are de-energized, tested de-energized, and properly grounded. In that state there is no electrical energy available to the equipment, so it’s safe to work.

If the pantographs are up, there could still be voltage present and a path for current. Merely stopping the train doesn't change the electrical status of the lines. Having a permit alone doesn’t guarantee that power is actually de-energized and grounded; verification and grounding are required to remove the live condition.