How to Wire an Arc Welder Directly into My Breaker Box

Determine the maximum amp draw for your arc welder by looking in the owner's manual. Go to the "Common Cable and Wire" link under Resources to choose the wire gauge and breaker size for your welder. This choice is important for safety. If you are unsure, consult a local electrical store for advise.

Turn the power off to the entire building by opening the main breaker. Confirm that the power is off by double-checking if any device in the house has power. Remove the screws that fasten the cover on the electrical panel and remove the cover.

Find two open slots in the panel for the 220-volt breaker. Open the breaker's switch so that it is in the "Off" position.

Insert the breaker into the center of the panel. Push down on the outside of the breaker until it snaps in place.

Strip 3/8 of an inch of insulation off the three conductors in the insulated wire. Insert these wires through an access hole in the side of the electrical panel. Pull the wire into the panel so there is enough wire to make connections to the breaker, neutral bus bar and ground. Secure the wire to the panel by tightening the compression mechanism with a screwdriver.

Loosen an empty terminal on the neutral bus bar, which has white wires. Insert the white wire from the three-conductor wire in this terminal and tighten it down. Loosen an empty terminal on the ground bus bar, which has green or bare wires. Insert the green or bare wire into this terminal and tighten it down.

Loosen the two terminals on the 220-volt breaker with a screwdriver. Insert the red and black wires into each of these terminals and tighten them down. Install the cover back on the panel by reversing the process used to to remove it. Leave the power for the building in the "Off" position.

Run the insulated wire to the location where you wish to make the connection to the arc welder. Insert the wires through the side of the electrical box and pull 6 inches of wire inside. Tighten the compression mechanism on the inside of the electrical box to secure the wire.

Insert the wire from the welder in the other side of the electrical box. Pull 6 inches of wire inside the box. Tighten the compression mechanism to secure the wire. Strip 3/8 of an inch of insulation off the wires coming from the welder.

Loosen the grounding screw in the electrical box. Wrap the two green or bare wires around this screw and tighten it down.

Twist together the two white wires and install a twist-on wire connector on top. Twist together the two red wires and install a twist-on wire connector on top. Twist together the two black wires and install a twist-on wire connector on top.

Push the wires neatly into the electrical box. Secure the cover with the screws provided. Have you local building authority inspect your wiring before turning the power back on.