How to Wire and Install Single-pole Switches

Light switch repair
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  • 01 of 05

    Single-pole Switch Installation - Turn Off The Power

    A photo of a breaker being shut off.
    Turning Off a Breaker - Photo. Timothy Thiele

    The first step in installing a single-pole switch is to turn off the power to the circuit that you'll be working on. To do that, simply go to your electrical panel and turn off the breaker feeding that circuit. In the event that you have a fuse panel, you'll have to locate the fuse that controls that circuit. Simply find the fuse and unscrew it from the socket.

    To check this, use an electrical tester to see that the power is on before you turn off the breaker or unscrew the fuse. If the...MORE tester shows power, then proceed to turn off the circuit. If the switch controls a light in the room, verify that the light is off after turning off the power at the electrical panel. Either way, electrical safety should be your first concern.

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  • 02 of 05

    Remove An Existing Single-pole Switch

    A photo of a switch being installed or removed.
    Switch being removed. Timothy Thiele

    Single-pole switch removal is easy enough to do. First, remove the two straight-bladed screws that hold the switch cover plate on and remove the cover plate. Be careful to place them somewhere safe so you can install them later. Then, remove the two screws that hold the switch to the junction box.  These screws usually allow you to use a straight or Phillips tip screwdriver to remove them. I prefer a powered screw gun or drill with a bit. Carefully pull the switch from the box and check it once...MORE more to be sure the power is off to the circuit feeding the switch.

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  • 03 of 05

    Remove The Existing Switch Wiring

    Single-pole Switch Being Disconnected
    Single-pole Switch Being Disconnected. Timothy Thiele

    A single-pole switch has three wires connected to it, a hot wire, a switch leg and a ground wire. If your switches don't have all three, it's time to change them right away. The hot wire is the feeder wire that is connected to the circuit breaker or fuse in the electrical panel. This wire is connected to one of the side brass terminals of the switch.

    The switch leg is the wire that feeds the light from the switch. When the switch is turned on, the electricity flows through the switch to...MORE the light. This wire connects to the other brass terminal on the side of the switch.

    The ground wire is either the bare or green wire and is connected to the green-colored screw of the switch. This screw is located at one of the ends of the switch and is bonded to the metal bracket of the switch that attaches to box.

    Using a screwdriver, unscrew the screws and remove the switch wires from the switch one at a time. It's a good idea to observe the way the wires were connected.

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  • 04 of 05

    Install A Single-pole Switch

    Single-pole Switch Being Disconnected
    Single-pole Switch Being Disconnected. Timothy Thiele

    Once the old switch is removed, replace it with a new switch and I like to start with the ground wire first. Connected the green or bare copper wire to the green screw on the switch. Next, connect the hot and switch leg wires to the two brass-colored screws located on the side of the single-pole switch.  Tighten the screws in a clockwise motion. This ensures that the wire opening tightens around the screw and that it doesn't open up while tightening the screw. This is a very important step...MORE and makes all the difference in the world for a secure connection.

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  • 05 of 05

    Install A New Single-pole Switch

    A photo of a switch being installed or removed.
    Timothy Thiele

    Once a single-pole switch is correctly wired, I like to hold the switch in one hand and I tug each of the wires snugly to ensure they are indeed connected properly. Gently push the excess wires into the junction box and carefully press the switch into the opening. Use a screwdriver to screw the two screws on the switch into the mounting holes located in the junction box. Make sure the switch is plumb when tightening the screws by using a level to plumb it up. There is nothing worse than a...MORE crooked switch in plain sight.

    Now, replace the cover plate to the switch and install the two mounting screws. Make sure the plate is plumb or level b using the same level. Once again, we want a nice looking replacement switch job when we are done.