Disconnect the device from its power source. Double-check that the power is off to avoid being electrocuted.
Strip 3/8 inches of insulation from three of the power wires with wire strippers.
Loosen the three terminal screws on the back of the Cooper plug.
Insert the black, hot wire into the "+," or positive terminal on the plug and tighten it down.
Insert the white, neutral wire into the "-," or negative terminal on the plug and tighten it down.
Insert the green, or bare wire into the ground terminal on the plug. Tighten it down.