What is the maximum speed at which a pantograph may be raised?

• A. 30 mph
• B. 60 mph
• C. 50 mph
• D. 70 mph

Answer: (B)

Raising the pantograph is a controlled mechanical action that must be done within a safe speed window. The pantograph is the device that collects power from the overhead wire, and doing this deployment too quickly exposes it to sudden aerodynamic forces and misalignment as it emerges into the airstream. Setting a maximum of 60 mph provides enough time to verify proper alignment, avoid excessive wear or stress on the pantograph and the catenary, and prevent arcing at the moment contact is made. Lower speeds are allowed but slower operation isn’t necessary, while speeds above 60 mph are not permitted because they increase the risk of damage or unsafe contact.