01 of 07
Garbage Disposal Wiring Basics
Garbage disposals, or disposers, can be connected with a cord and plug or they can be hard-wired with circuit wiring connecting directly to the disposal. When connected with a cord, the cord plugs into a switched-controlled receptacle (electrical outlet) that is typically installed in the sink-base cabinet. When hard-wired, the circuit wiring connected to the disposal runs to a switch that is installed in an electrical box either in the base cabinet or on a wall near the sink. The wiring between the disposer and switch typically is installed inside the flexible metal conduit ("Greenfield") to protect the exposed portion of the circuit.
Cords typically are not sold with disposals and must be purchased separately. Be sure to use a grounded cord with the appropriate voltage and amperage ratings for your garbage disposal. It's usually easier to connect the cord to the disposal before mounting the disposal under the sink, but you can complete the wiring after the unit is mounted if desired.
Continue to 2 of 7 below.
- Phillips screwdriver
- Appliance power cord with plug (grounded)
- Cable Clamp
- Wire strippers
- Plastic wire connectors (wire nuts)
02 of 07
Remove the Wiring Compartment Cover
Remove the metal cover from the wiring compartment on the bottom of the garbage disposal unit. On most units, the cover is secured with a single screw. Remove the screw with a screwdriver and set the pieces aside (you will need them later).Continue to 3 of 7 below.
03 of 07
Install a Cable Clamp
Install a cable clamp into the hole near the wiring compartment. Insert the treaded end of clamp into the hole and secure it on the inside of the unit's base plate with the clamp's nut. You have to reach through the wiring compartment to install and tighten the nut.Continue to 4 of 7 below.
04 of 07
Strip the Cord Wires
Prepare the cord wires for connection by stripping about 3/4 inch of insulation from the ends of each of the three cord wires, using a wire stripper. If the cord wiring is stranded copper, be sure to use the "stranded" notches on the wire stripper. If the wiring is solid copper, use the "solid" notches. Stranded copper is slightly larger than solid copper of the same nominal size.Continue to 5 of 7 below.
05 of 07
Install the Cord
Feed the end of the cord (with the stripped wires) through the cable clamp and into the wiring compartment. Secure the cord in the clamp by tightening the two screws on the clamp. The cord should be held securely but not compressed or deformed by the clamp.Continue to 6 of 7 below.
06 of 07
Connect the Wires
Wrap the bare-copper end of the green (ground) wire of the cord clockwise around the ground screw on the disposal. Tighten the ground screw with a screwdriver to secure the wire. Connect the white (neutral) cord wire to the white (neutral) wire on the disposal using a wire connector. Connect the black (hot) cord wire and the black (hot) wire of the disposal with a wire connector. Gently tug on each of the wires to make sure it is secure.Continue to 7 of 7 below.
07 of 07
Reinstall the Wiring Compartment Cover
Carefully tuck the wires into the wiring compartment. Reinstall the compartment cover, securing it with its screw.
Note: After the disposal is completely installed and the plumbing connections are made, plug in the disposal cord to a switch-controlled, GFCI-protected receptacle. GFCI protection is required by the National Electrical Code because the receptacle is located within 6 feet of the kitchen sink (in most cases).