What is the function of door interlock systems on passenger cars?

What is the function of door interlock systems on passenger cars?

• A. Prevent door operation when the car is not properly aligned or when the train is in motion, ensuring passenger safety and door integrity.
• B. Allow door operation whenever weight is detected.
• C. Lock doors only when brakes are applied.
• D. Open doors during motion for ventilation.

Answer: (A)

Door interlock systems are safety features that ensure doors can only be opened under safe conditions. They check that the car is properly aligned with the platform and that the train is not moving (or is at a safe speed) before allowing door operation. This prevents passengers from being exposed to moving trains, keeps the door hardware from being damaged, and ensures boarding occurs only when it’s safe. The interlock relies on sensors that monitor alignment, door position, and the train’s motion state; if any condition isn’t met, the door controls stay locked. When alignment is correct and the train is stopped or moving safely, the interlock releases and doors can be opened for boarding. Opening doors due to weight alone, or opening during motion for ventilation, would create safety risks and aren’t how these systems are designed.

Door interlock systems are safety features that ensure doors can only be opened under safe conditions. They check that the car is properly aligned with the platform and that the train is not moving (or is at a safe speed) before allowing door operation. This prevents passengers from being exposed to moving trains, keeps the door hardware from being damaged, and ensures boarding occurs only when it’s safe. The interlock relies on sensors that monitor alignment, door position, and the train’s motion state; if any condition isn’t met, the door controls stay locked. When alignment is correct and the train is stopped or moving safely, the interlock releases and doors can be opened for boarding. Opening doors due to weight alone, or opening during motion for ventilation, would create safety risks and aren’t how these systems are designed.