How to Install an Electrical Distribution Panel

Cut the plywood backing of the electrical panel by placing the panel on a piece of 3/4-inch plywood and drawing an outline of the panel with a pencil. Cut the outline with a wood saw. Measure the width of the wood and mark its center.

Punch a knockout on top of the panel, using needle-nose pliers. Place the electrical panel upright against the wall, just below the feeder pipe containing the main electrical cable running from the electric meter. Slip the feeder cable through the center knockout on top of the panel, and then insert the tip of the feeder pipe into the knockout. Align the panel horizontally and vertically and draw its outline with a pencil. Locate the studs that run within the outline, using a stud finder and mark the location of the studs.

Hold the plywood against the outline that you drew on the wall and nail the plywood onto the studs. Slip the tip of the feeder pipe through the top knockout and screw the electrical panel onto the plywood, using screws supplied with the panel. Secure the pipe by installing the lock-nut onto the threaded end of the pipe.

Pull the feeder wires coming from the electric meter and remove one inch of insulation from the tip of each wire, using a utility knife. Run each of the two 110-volt black feeder wires to the terminal lugs on the main circuit breaker. Route the neutral wire (white) to the terminal lug on the neutral buss. Apply anti-oxidant compound in case the wires are made of aluminum and plug each wire to its corresponding lug. Tighten all terminal lugs firmly with an Allen wrench.

Remove the knockouts on either side of the panel and slip the wires coming from each circuit through the knockouts. Route each neutral (white) wire to a terminal in the neutral buss bar. Route each green or bare wire to a terminal in the grounding bar. Route each black (hot) wire to a terminal screw on its matching 110-volt, or 220-volt circuit breaker.

Trim any excess wire. Cut away 1/2 inch of insulation from the tip of each wire with a wire stripper. Insert each wire tip into the slot under its corresponding terminal screw. Tighten each screw firmly, using a slotted screwdriver and replace the electrical panel cover.