How does a driver isolate defective pantographs?

Isolating defective pantographs is crucial for maintaining safety and proper functioning on the railway system. The process involves disconnecting or disabling the pantograph that is not operating correctly to avoid potential hazards or further damage.

Trip Panto Control MCB on the affected motor is the correct answer as this action directly cuts power to the defective pantograph, effectively isolating it from the operational circuit. This step is essential to prevent any electrical faults or short circuits that may arise from a malfunctioning pantograph. By tripping the MCB (Miniature Circuit Breaker), you can ensure that the transport system remains operational with the other pantographs while addressing the issue with the defective one.

Other options, while relevant to the overall management of pantograph issues, do not specifically isolate the defective unit in the hands-on, operational manner that tripping the MCB does. For instance, ensuring the master key is on or notifying maintenance could be part of the system's protocols but do not directly address isolating the faulty part from the system. Lowering the defective pantograph automatically might not guarantee isolation from electrical faults, as it could still remain connected to the power unless the MCB is tripped.