A single phase ac induction motor has two windings, one is a run winding and the other is called a start winding. Strat winding can only work for a very short time to avoid overheated. A _____________ switch is installed inside motor to disconnect the strat winding when the motor speed reached 75% RPM.
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An induction motor's rotor can be either wound type or ????????-???? type.
The common weakness for a single phase induction motor is it has a very small start torque. To increase its start torque, a strating _____________is connected in series into start winding which will be disconnected when the speed reaches 75% RPM by centrifugal switch.
To change the speed of a DC motor, you can change the applied DC____________. To change the speed of an AC induction motor you must change the ____________ of the AC power supplied.
The stepping size may vary from 0.72° to 90°. This means that a setp motor shaft may turn from 0.72° to 90° for every input_________.