Which type of switch is used to transition a dryer motor from starting to running mode?

Which type of switch is used to transition a dryer motor from starting to running mode?

• A. Relay
• B. Magnetic switch
• C. Centrifugal switch
• D. Push-button

Answer: (C)

In a dryer motor, starting torque is provided by the starting winding (often with a capacitor). A centrifugal switch uses the rotating speed of the motor to open the circuit to that starting winding once the rotor reaches a certain speed. This automatic switch leaves the run winding energized for normal operation, preventing the starting winding from overheating and wasting current. That's why the centrifugal switch is the correct choice—it specifically handles that automatic transition from starting to running. Relays or magnetic switches are control devices in circuits but don’t perform the internal transition to drop the starting winding, and a push-button would require manual action, not automatic startup.

In a dryer motor, starting torque is provided by the starting winding (often with a capacitor). A centrifugal switch uses the rotating speed of the motor to open the circuit to that starting winding once the rotor reaches a certain speed. This automatic switch leaves the run winding energized for normal operation, preventing the starting winding from overheating and wasting current. That's why the centrifugal switch is the correct choice—it specifically handles that automatic transition from starting to running. Relays or magnetic switches are control devices in circuits but don’t perform the internal transition to drop the starting winding, and a push-button would require manual action, not automatic startup.