Adding A Circuit Installing a new electrical circuit is simple and doesn’t take special skills. Most of the work is done outside the service panel. To get a breaker that will fit in your panel, jot down the brand and model number or bring a sample breaker to the store.

First, determine whether your service panel can accommodate a new breaker, and plan a circuit so it won’t be overloaded. If the circuit will be in a bathroom or along a kitchen countertop, consider installing a GFCI breaker so that you won’t have to install individual GFCI outlets. Install the new boxes. Run cable from the boxes back to the service panel. Electricians call this practice a “home run.” Hook up the devices and fixtures. Now you’re ready to power the new circuit by installing a new breaker and connecting the wires. Make sure the breakers and boxes you buy are made by the same company.

Follow These Steps

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  • Step One

    SHUT OFF MAIN POWER
    Work during the day and have a reliable flashlight on hand. Turn off the main circuit breaker. All the wires and circuit breakers in the panel are now de-energized except for the thick wires that come from the outside and connect to the main breaker. Don’t touch the thick wires.

  • Step Two

    REMOVE A KNOCKOUT
    Remove the service panel cover. Remove a knockout slug from the side of the service panel and install a cable clamp. Also remove a knockout tab from the panel cover. (For a double-pole breaker, remove two knockouts.)

  • Step Three

    CLAMP THE CABLE
    Determine how far the wires must travel to reach the breaker and the neutral bus bar. To avoid tangles, plan a path around the box’s outside perimeter. Strip about a foot more sheathing than you think you will need. Thread the wires through the clamp and secure the cable. Don’t over tighten.

  • Step Four

    CONNECT THE NEUTRAL WIRE
    Run the neutral wire toward an open terminal in the neutral bus bar, bending the wire carefully so it will easily fit behind the panel cover. Cut the wire to length and strip off about ½” of insulation. Poke the end into the terminal and tighten the setscrew. Connect the ground wire to the ground bar (or neutral bus bar if there is no ground bar).

  • Step Five

    WIRE THE NEW BREAKER
    Run the hot wire, bending it carefully so it will easily fit behind the panel cover. Cut the wire to length. Strip off ½” of insulation. Poke the wire into the new breaker terminal. If bare wire is visible, remove the wire, snip it a little shorter, and reinsert it. Tighten the setscrew.

  • Step Six

    SNAP THE BREAKER INTO PLACE
    Make sure the breaker is in the off position, and then slip one side of the breaker under a tab to the right or left of the hot bus bar. Push the other side onto the bus bar until the new breaker is flush with the other breakers. (Some brands of breakers may require a slightly different installation method; check the instructions.) Restore power, turn off the breaker, and try the switches or receptacles to see if they’re getting power.

  • Step Seven

    INSTALLING DOUBLE-POLE BREAKERS
    Check to see if you have the two free posts you’ll need for a 240-volt breaker. (A tandem breaker takes up only one spot and can be substituted as long as there are two lugs for it.) Shut off the power. Connect the black and red wires to the breaker terminals. Connect the white wire to the neutral bus bar and the ground wire to the ground bar (or neutral bus bar if there is no ground bar).

Skill Scale
Novice
Time Required
2 hours
Shopping List:

tools

Hammer

Screwdriver

Lineman’s Pliers

Combination Stripper

materials

Cable and Clamp

New Circuit Breaker

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