How to Wire a Variable Speed Motor

A variable speed motor enables you to control the speed at which it operates. The motor may use an internal rheostat, or may have several speed settings which you select using a switch on the motor. Wiring a variable speed motor is the same as wiring a single speed motor, as the speed control function is an integral part of the motor. Therefore, you only need to connect two wires to the motor’s terminals.

Get your wire prepared so you can connect it to your variable speed motor. Use wire strippers to remove the outer plastic covering on the wire so the two internal wires are visible; about two inches is fine.

Remove ¼ inch of the plastic off the end of the two colored wires using the wire strippers. This exposes the metal core which you need to twist using your fingers so the strands stay together.

Loosen the two terminal screws on the variable speed motor using a screwdriver. They are usually on the rear on the motor.

Slide the metal core on the end of the black wire under the terminal screw labeled "-" then tighten the screw using a screwdriver.

Slide the metal core on the end of the red wire under the terminal screw labeled "+" then tighten the screw using a screwdriver. Check both connections are securely in place on the variable speed motor by gently tugging on the wires.