Dimmer switch wiring might seem intimidating, but it only requires four wire connections.
For most do-it-yourselfers, installing a single-poledimmer switchis a fairly simple task that takes less than 30 minutes.
Before You Begin
Before you get started, consider the size of your junction box.
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It needs to be large enough for a new dimmer switch.
Total the wattages of the bulbs served by the switch.
Purchase a dimmer switch capable of dimming either LED or incandescent bulbs or both types.
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Example
Atrack lightingfixture has four incandescent 60W bulbs, for a total wattage demand of 240W.
Use a 600W-rated dimmer to control these lights.
Rock the switch outward to turn it off.
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Remove the Switch Mounting Screws
Unscrew the mounting screws on the existing light switch.
Do not touch the screw terminals on the side of the switch or any wires.
Test for Power
Check each wire in the box with the non-contact circuit tester.
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Touch the tip of the tester to each screw terminal on the switch.
If a ground wire is also attached, disconnect it from the green ground screw.
Wire nuts, if any, can be screwed off by turning them counter-clockwise.
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Clean up the wires by straightening out curled exposed ends.
Mangled wires should be trimmed.
It is only used in three-way installations where two switches control a light.
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Cap off this wire with a wire nut, then wrap it with electrical tape.
Complete the Installation
Carefully fold the wires and tuck them into the box.
As the screws tighten, the switch will nudge the wires deeper into the box.
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Turn on the Circuit Breaker
Go to the service panel and flip the circuit breaker back on.
Return to the dimmer switch and test its operation.
With any electrical repair, though, there is the potential for dangerous, or even lethal, shock.
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If you are not confident in your abilities, it’s best to call in an electrician.
If not, you’ll likely need an electrician’s help.
When conducting electrical work at home, you should always check local electrical code requirements first.
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On a single-pole dimmer switch, there will be a total of three wires that go on the switch.
There will be two wires that attach to the circuit wires in the box.
There will be a third green wire that attaches to the circuit grounding wire.
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The fourth wire (red/white striped) is not used.
In most cases, dimmer switches are wired the same way as a regular switch.
C or COM stands for “common,” and it supplies power to the switch.
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Lumens and the Lighting Facts Label.
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