Red Seal Electrician Practice
Motor controlsQuestion 86 of 1506

What primary purpose do circuit breakers and fuses have compared with overload heaters?

  1. They protect only the control transformer, not the power conductors of the motor
  2. They measure motor speed and send a signal to the overload
  3. They replace the motor contactor when it needs maintenance
  4. They protect the power conductors, while the overload heaters protect the motor
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Correct answer: They protect the power conductors, while the overload heaters protect the motor

Heaters give motor overcurrent protection.

Source: Lessons in Electric Circuits IV: Digital (Kuphaldt), 5.2: Contactors

Practice motor controls

Questions last reviewed: 18 October 2026