What do electrical and mechanical interlocks prevent in a magnetic reversing starter?

• A. Coil Energizing
• B. Motor Overload
• C. Short Circuits
• D. Power Supply Failure

Answer: (A)

Interlocks in a magnetic reversing starter are there to stop the two control circuits from being energized at the same time. When one direction is chosen, the electrical interlock and the mechanical interlock work together to prevent the opposite coil from getting power and to physically block its contactor from closing. This guarantees the motor isn’t commanded to run in both directions or create a conflicting path.

So, the main idea is that interlocks prevent energizing the coil for the opposite direction, ensuring only one coil is energized at a time. Other protections handle overloads, short circuits, or power supply issues, but interlocks are specifically about preventing both coils from energizing simultaneously.