Shaded Pole Motors: the YZF Series

How a shaded pole motor works

The stator of a shaded pole motor has salient poles wound with a single coil. A short-circuited copper ring, the shading ring, is set into part of each pole face. When alternating current flows in the main coil, the current induced in the ring delays the magnetic flux in the shaded part of the pole. The flux therefore sweeps across the pole face, and the squirrel-cage rotor follows it.

Because the shifted field comes from the poles themselves, the motor needs no start winding, capacitor or centrifugal switch. It turns in one direction, set by the side of the pole that carries the ring. Starting torque is modest and a large share of the input power becomes heat, so the design suits small fans with a light, steady load rather than machines that start under load.

YZF series at a glance

• YZF 18 shaded pole fan motor

  For refrigerator cooling fans.

• YZF 26 condenser fan motor

  For condenser fans.

• Copper-wound YZF series

  Stator wound with copper wire.

• Aluminium-wound YZF48N

  Stator wound with aluminium wire.

Each range page lists its models by voltage and frequency with input power, rated output, current, speed, air volume, fan blade diameter and outline dimensions. Values differ between ranges, so read them on the page of the range you are considering.

Supply voltage and frequency

Speed and current of a shaded pole motor depend on the supply. On a 60 Hz supply the motor runs faster than on 50 Hz, and on a 110-120 V supply it draws more current than a 220-240 V version of the same model.

Voltage versions

Fengyin motors are offered in 110-120 V and 220-240 V versions; see each model’s table.

Information to send with an enquiry

• Supply voltage and frequency of the equipment
• Air volume or fan duty you need, and the fan blade diameter
• Space available in the fan housing, or your mounting drawing
• Winding preference (copper or aluminium), if your specification sets one
• Annual quantity and target delivery schedule

With these details we can point you to the model rows that fit and quote them. Fengyin motors go into commercial refrigeration equipment and household appliances. For the BMC-encapsulated motor, see the BMC lightweight fan motor.