The shaded-pole induction motors have _____________ compared with other motor types and may not be suitable for applications with ___________ or where precise speed control is necessary.

Shaded-pole induction motors

• The shaded pole induction motor is simply a self-starting single-phase induction motor whose one of the poles is shaded by the copper ring.
• The copper ring is also called the shaded ring. This copper ring acts as a secondary winding for the motor. The shaded pole motor rotates only in one particular direction, and the reverse movement of the motor is not possible.
• Shaded Pole motors have low starting torque, low cost, and low efficiency, and are used for light loads such as fans and blowers found in homes (OR) it can be said as Shaded Pole motors have low starting torque, low cost, and low efficiency, and are not suitable for heavy loads or where precise speed control is necessary.
   

Shaded Pole Induction Motor Working:

• When the supply is connected to the windings of the rotor, the alternating flux is induced in the core of the rotor. The small portion of the flux links with the shaded coil of the motor because it is short-circuited.
• The variation in the flux induces the voltage inside the ring because of which the circulating current induces in it. The circulating current develops the flux in the ring which opposes the main flux of the motor.
• The flux induced in the shaded portion of the motor, i.e., a, and the unshaded portion of the motor, i.e., b have a phase difference. The main motor flux and the shaded ring flux also have a space displacement by an angle of 90°.
• As there is time and space displacement between the two fluxes, the rotating magnetic field induces in the coil. The rotating magnetic field develops the starting torque in the motor. The field rotates from the unshaded portion to the shaded portion of the motor.

Applications of the Shaded Pole Induction Motor:

• ​They are suitable for small devices like relays and fans because of their low cost and easy starting.
• Used in exhaust fans, hairdryers, and also table fans.
• Used in air conditioning and refrigeration equipment and cooling fans.
• Record players, tape recorders, projectors, photocopying machines.
• Used for starting electronic clocks and single-phase synchronous timing motors.