How to Install a Light Switch by Inserting a Wire Into the Hole
- 1). Turn off the circuit breaker for the branch circuit. Turn on the non-contact voltage tester, and bring it near the cover plate of the switch you are going to remove, or near the circuit wires. The tester will beep loudly if voltage is still present on the wiring. If the tester does not beep, you have turned off the right circuit breaker.
- 2). Remove the two cover-plate screws, and remove the switch cover plate. Remove the two screws from the plaster ears of the switch, and pull the switch out of the electrical box.
- 3). Disconnect the wires from the old switch. You can save some time by simply cutting the wires off with the wire cutters. Make the cuts as close to the old switch as possible. Do not cut the bare copper ground wire. The ground wire is the one wire that will have to be connected to the new switch using a screw terminal. If you do cut it, you will need to form a new loop on it before connecting the switch.
- 4). Remove 1/2 to 3/4 inch of insulation from the circuit wires, using the wire strippers. Use the strip gauge, the groove machined into the back of the switch, to make sure you have removed the correct length of insulation.
- 5). Push the stripped ends of the wires all the way into the holes until you cannot push them any farther. Tug on them to be sure they are being held firmly in place.
- 6). Place the looped end of the bare copper ground wire under the green, octagon-shaped ground screw so the loop is oriented in a clockwise direction. Tighten the screw down on the ground wire.
- 7). Push the switch into the box, and secure it in place with the appropriate screws. Install the cover plate.
Return the branch circuit breaker to the on position.
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