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How to Control the Speed of a Shaded Pole Electric Motor

Simple, shaded-pole motors work well in house fans and other applications where low starting torque won't affect performance. The motor responds well to variations in voltage provided the torque required changes with the speed of the motor. Controlling the voltage to the motor with a solid-state speed controller works best for most applications. Ceiling fan speed-control modules include a solid-state, motor-speed controller in their design and work well with shaded-pole motors.

Things You'll Need

Lamp cord
Lamp cord with polarized plug
Multimeter
Wire nuts
Ceiling fan speed controller
Screwdriver

Instructions

- 1
  Pull the ends of the lamp cords apart by grasping both wires and pulling until the cord separates into two separate, 6-inch wires. Strip the insulation from 1/2 inch of each wire. Strip the ends of the two wires from the shaded pole motor.
- 2
  Set the multimeter to read ohms. Touch one probe to the wide plug blade and the other to one of the stripped wire ends. If the resistance is near "zero," mark the wire with the marker; otherwise mark the other wire.
- 3
  Insert the end of the lamp cord wire with the plug, and one end of the other lamp cord wire into a cable hole in the back of the wiring box. Place a wire nut over the bare end of the marked wire, the bare end of a wire from the other lamp cord and the white wire from the fan speed-control module. Twist the wire nut clockwise until the lamp cords begin to twist, indicating the connection is made.
- 4
  Place a wire nut over the end of one motor wire and one lamp cord wire. Twist the wire nut clockwise until the wire begins to twist. Repeat for the other motor wire and other half of the lamp cord wire.
- 5
  Hold the bare end of the black wire from the fan controller together with the bare end of the remaining plug wire. Cap it with a wire nut and twist until connected. Connect the red wire from the fan controller to the remaining motor wire the same way.
- 6
  Mount the fan speed control in the wiring box using the supplied screws and the screwdriver. Place the fan speed-control cover on the box and attach it with the two supplied screws. Plug the lamp cord into an outlet and adjust the motor speed using the fan speed-control module.

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