How to Wire a Two-Speed Electric Fan Motor

Two-speed electric fans usually use two different field coils for speed control, or they use resistance speed control. In the first method the motor is equipped with two different field coils, each designed to produce a different speed. The speed is changed by supplying power to a different field coil. The second method is used mostly with DC motors. Resistors are placed inside the speed control switch. The motor has only one field coil whose speed is altered when resistors change the voltage.

• 1

  Cut one piece of electrical wire and strip 1/2 inch of insulation off of each end. Connect one end of the wire to the positive terminal of the power source. Connect the other end to the positive terminal of the motor.

• 2

  Cut two pieces of electrical wire and strip 1/2 of an inch of insulation off of each end. Connect the low-speed terminal of the motor to the low-speed terminal of the switch using one of the two wires. Connect the high-speed terminal of the motor to the high-speed side of the switch with the second wire.

• 3

  Cut another wire. Connect it from the negative terminal of the power source to the supply side (power input side) of the switch.

• 4

  Turn the switch to the first speed position, and make sure the fan starts. Turn the fan to the second speed position to verify that the motor changes to a higher speed.