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If the capacitor of a capacitor-start single-phase motor fails to open when the motor picks up speed,

If the capacitor of a capacitor-start single-phase motor fails to open when the motor picks up speed, Correct Answer The capacitor will be damaged

Capacitor start induction motor:

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  • A single-phase motor has two windings: the main winding and auxiliary winding. Both windings are placed on the stator.
  • The motor has a centrifugal switch inside its case, attached to the motor shaft.
  • The centrifugal switch turns on a circuit, providing the needed boost to start the motor.
  • Once the motor comes up to its operating speed, the switch turns off (disconnects auxiliary winding) the boost circuit, and the motor runs normally.
  • The centrifugal switch is used to disconnect the starting winding when the motor has picked up 50 - 70% speed
  • If the centrifugal switch fails to open at 50 to 70 percent of the synchronous speed of the motor, then the starting winding will overheat and burn out and the motor will not start next time.

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