How to Mount an Electrical Service Load Center Panel

Look at the service drop coming from the utility pole and check if it has been disconnected by the utility company from the feeder wires running into your electric meter. Alternatively, check if the electric meter has been removed from its socket. For you to be able to work on the panel, the feeder wires running into the electrical panel must not be connected to the power line coming from the utility company. Disconnecting the service drop or unplugging the electric meter are common ways to disconnect power from the utility company.

Trace the electrical panel's outline on 3/4-inch thick plywood. Cut the outline with a wood saw for the plywood backing. Decide where the panel will be installed. Locate the studs running vertically along the wall using a stud finder. Mark the studs with a pencil.

Find the exact spot where the panel should be mounted and nail the plywood onto the studs. Ensure the plywood is properly aligned horizontally and vertically with a level. Remove the panel front cover and punch the knockouts at the top-center and on both sides of the panel with needle-nose pliers. Plug cable clamps into the knockouts and screw a lock nut firmly onto each cable clamp. Mount the panel upright onto the plywood using the screws supplied with the panel.

Plug the main circuit breaker into its corresponding slot in the panel board. Then plug all auxiliary circuit breakers. Turn off all breakers by flipping switches to the "off" position. Slip the three feeder wires running from the electric meter into the electrical panel via the top center knockout. Pull the cables from inside the panel and use a utility knife to remove one inch of cable covering from the end of each.

Plug the tip of the two red/black "hot" cables into each terminal lug in the main circuit beaker. Plug the neutral cable, which is black with white markings, into the terminal lug in the neutral buss bar. Tighten all lugs with an Allen wrench. Pull on each cable to make sure you have no loose connections.

Slip each cable coming from electrical outlets and light receptacles through a knockout on either side of the panel. Cut each cable after about two feet from the knockout. Using diagonal pliers, remove the cable sheathing to expose the inner wires.

Route each wire neatly to its corresponding terminal in the following order: white wires to individual terminal screws in the neutral buss bar; green/bare wires to individual terminal screws in the grounding bar; and black/red wires to a terminal screw in its corresponding circuit breaker. Trim any excess wire and strip 1/2 inch from the tip of each wire using a wire stripper. Plug each wire to its terminal screw and tighten each screw firmly.

Screw the cover of the electrical panel into place. Schedule the local electrical inspector to review your work after you have completed wiring the panel and circuits.