How to Install Another Circuit Breaker for My Shed

Turn the power off to your circuit breaker box by flipping the main breaker to the off position. This breaker may be located on the outside of your home where the connection from the main power line comes in.

Remove the panel from your circuit breaker box. You may need to unscrew it to do this. Be extremely careful not to touch any wires either outside or inside the box. It is especially important that you do not touch the wires going into the main breaker from the house's main power connection. These wires will always be hot, even if the main breaker is turned off, and touching them could kill you. In most breaker boxes, they will be located near the top and they will be thicker and heavier than the other wires.

Use your voltmeter to ensure that the power is truly off in your breaker box. Take one probe and connect it to the neutral bus bar while connecting the other probe to the bar that has connections from all of the breakers. If the voltmeter does not show 0 volts, the power is still on.

Remove knockouts from your breaker box's cover and side for the new circuit. To create a space, simply knock one of the breaker space covers out with a hammer and insulated screwdriver. To make room for the wire to come into the breaker box, use the hammer and insulated screwdriver to knock out the side cover closest to the breaker space that you just opened up.

Pull the cable from your shed through the hole created in your box so that there is enough cable inside the box to reach the necessary connections. Use a cable connector that fits your particular breaker box to lock the cable in place.

Strip the ends of the wires inside the cable from your shed to expose enough wiire to attach inside your breaker box. Although the amount of wire you need will vary depending on how your breaker box is configured, most applications will require you to strip the insulation from 1/2 inch to 1 inch of wire.

Connect the white wire to your breaker box's neutral bus bar by loosening a screw on an unused terminal on the bus bar, coiling the wire under the screw, and tightening the screw to lock the wire in place.

Connect the cable's ground wire to your ground bar using the same process that you used to connect the white wire to your neutral bus bar. If your box does not have a separate ground bar, connect the ground wire to an additional open terminal on the neutral bar.

Insert the black wire, which is the "hot" wire, into the connection terminal on your breaker, and tighten the screw to lock it into your breaker. Note that the actual connection method may vary slightly depending on the design of your circuit breaker switch.

Place the new circult breaker into the appropriate place in the breaker box and replace the cover, tightening any screws that you may have loosened or removed.

Switch your main breaker back on, and test your newly added circuit and breaker.