When is it permissible to raise Pantograph(s) again after a hand signal to drop them?

When is it permissible to raise Pantograph(s) again after a hand signal to drop them?

• A. Immediately after signaling area.
• B. After one Pantograph passes.
• C. Immediately raise after the last pantograph passes.
• D. After all Pantograph(s) have passed the affected area.

Answer: (D)

The main idea is safety—only restore pantograph power after the train is fully clear of the danger zone. When a hand signal to drop pantographs is given, they’re lowered to prevent contact with energized overhead wires in the affected area. Re-raising them should wait until every pantograph on the train has passed through that area, so there’s no risk of any pantograph re-contacting the catenary while still within the hazard zone. Raising immediately after signaling area, after only one pantograph passes, or immediately after the last pantograph passes doesn’t guarantee the entire train is clear, which could lead to contact or arcing with the overhead. Waiting until all pantographs have passed ensures a safe, complete clearance before power is restored.

The main idea is safety—only restore pantograph power after the train is fully clear of the danger zone. When a hand signal to drop pantographs is given, they’re lowered to prevent contact with energized overhead wires in the affected area. Re-raising them should wait until every pantograph on the train has passed through that area, so there’s no risk of any pantograph re-contacting the catenary while still within the hazard zone. Raising immediately after signaling area, after only one pantograph passes, or immediately after the last pantograph passes doesn’t guarantee the entire train is clear, which could lead to contact or arcing with the overhead. Waiting until all pantographs have passed ensures a safe, complete clearance before power is restored.