The switch-leg component of an electrical wire circuit controls the electric current to lights or receptacles. The kind of circuit wiring in the switch is determined by the electricity that enters the circuit. Switches that operate lights or receptacles from several locations necessitate the use of an additional switch-leg circuit.
In general, knowing how to wire a switch leg is pretty simple. All you need to do is to prepare and connect the necessary wires, remove grounds, connect wires in the switch box, attach the leg wire to the switch, and finally connect and screw your light fixture.
In our guide we’ll go into more detail on the exact steps:Â
Easy Guide to Wire a Switch Leg
The switch-leg section of the circuit is made up of the switch and the two electrical wires that connect the outlet to the switch. A switch leg is something you would use, for instance, for a door switch. Follow these step-by-step guide to know how to wire a switch leg:
Step 1: Roll out the Wires

Connect a cable from the light to the switch box. Then, run a hot wire that comes off the plug and bypasses the switch box. The same hot wire connects the light. We now have two wires: one from the lamp to the switch box, and the other is the hot wire that passes the switch and goes directly to the light. That is all the conductors we require.
Step 2: Put a Label On

Pu a label on each wire, so you don’t get confused about which is what. In this case, the incoming power (black is the hot wire, white is the neutral wire) is labeled POWER, and the white conductor is labeled LOOP.
Step 3: Remove the Grounds

Remove the grounds. However, you must still connect the grounds, ensuring that, because this is a metal box, we have our ground screw in there and that one of these grounds is wrapped around that ground screw. Trim the excess, leaving at least 3 inches of it hanging out.
Step 4: Attach the Wires Together
First, let’s deal with the incoming power. The black and white wires represent the hot and neutral wires, respectively. Connect your white conductor wire to the black wire (hot).

Note: Most light fixtures will require a ground, but because I am connecting a keyless with a gold and silver screw, there is no place for it since it is a ceramic fixture with no metal parts you might touch. (1)
Step 5: Connect Wires in the Switch Box

The white wire in the switch box is no longer neutral; it is now the hot wire. Connect the ground wire to the switch. Next, connect the white wire (hot wire) to the switch; it doesn’t matter which side of the switch you connect it to.
Step 6: Attach the Leg Wire

Our black wire represents the switch leg. Connect the switch leg to the light switch, transmitting electricity back up to the lights to turn them on. Then, screw the light switch in inside the box and the wires attached to it. (2)
Step 7: Screw Your Light Fixture

Bend the hooks of your neutral and hot wires to attach the light fixture. Connect your neutral wire to your silver screw. Hook the switch leg to the golden screw after that. Finally, screw on the light fixture and turn on the power to see whether you correctly wired your switch leg. If it lights up, you did an excellent job!
Take a look at some of our related articles below.
- A wire rope sling with a strength
- How to cap off electrical wires
- What happens if ground wire is not connected
References
(1) ceramic – https://mse.umd.edu/about/what-is-mse/ceramics
(2) transmitting electricity – https://americanhistory.si.edu/powering/
transmit/trmain.htm
Video References
Terry Peterman
Electrician U