How To Wire A Light Switch
Whether you are placing in a new switch, or simply maintaining an existing one – knowing how to wire a light switch safely is an important skill for homeowners to have under their belt. Wiring a light switch might seem intimidating at first, but with the right guidance, it is a simple and manageable DIY project.
Ready for the challenge? Follow the simple steps below from WD-40® to discover how to wire a light switch, and you’ll be brightening your home in no time!
Things you will need
New light switch
Screwdriver
Voltage tester or multi-meter
Wire stripper
Step 1
Safety First
Before starting any electrical work, ensure the power to the circuit is completely switched off. Locate the correct circuit breaker in your fuse box and turn it off. You can usually find this in a garage or utility room. To be extra safe, use a voltage tester to confirm that there’s no electricity flowing to the switch.
Step 2
Identify your Wires
Once you have successfully turned off the power, you need to take some time to understand the wiring pattern in your home. Usually, a light switch controls a light fixture from a single location, but that is not always the case.
Once you have identified the correct wires, make sure you know which wires are live, neutral, and earth. The live wire is usually brown, the neutral wire is blue, and the earth wire is green/yellow.
Step 3
Remove the Old Switch
Now you know which wires you are focusing on, it is time to remove the old switch. Use a screwdriver to remove the screws holding the switch cover in place.
If the screws are tight, stiff, or corroded, don’t try and force them out – this can cause damage to your walls and tools. Instead, you can apply a small amount of WD-40® Multi-Use Product to help remove any build-up, loosen their grip, and remove them gently from the wall. The innovative formula will work to eliminate dust and dirt that may have built up on the screws, and lubricate them to help ease them out without undue force.
Once the screws are removed, slowly pull off the switch cover.
Step 4
Examine and Disconnect the Wiring
Now that the switch cover is removed, you have a clearer view of the wiring inside the switch. Take a moment to understand how the wires are connected to the old switch. You’ll typically find two or three wires: live, neutral, and earth. Remember, the live wire brings power to the switch, the neutral wire completes the circuit, and the earth wire provides safety.
Then, loosen the screws holding the wires in place on the old switch, and gently remove them. Be careful not to damage the wires or their insulation. To avoid confusion when re-wiring later on, label the wires with masking tape to remember which one is which.
Step 5
Prepare and Install the New Switch
Now that your old switch is fully disconnected, it’s time to prepare your new one for installation. If your new switch has multiple terminals, check the manual or manufacturer’s instructions to know which terminals are for live, neutral, and earth.
Then, use your wire stripper to strip a small portion of the wire ends if needed, ensuring you don’t expose too much of the wire.
Next, attach the wires to the corresponding terminals on the new switch. Tighten the screws securely to ensure good contact.
Step 6
Fix the New Switch Into Place
Now that your wires are attached to the new switch, carefully tuck the wires into the switch box, ensuring they’re not pinched or damaged. Then, attach the switch cover over the switch and secure it in place with screws.
Step 7
Test the Switch
Finally, it is time to test your handywork. Before you consider the job complete, give the switch one final inspection. Ensure all connections are secure, there are no exposed wires, and the switch cover is properly fixed.
Then, turn the circuit breaker back on and test the switch. If everything is wired correctly, the light should turn on and off as expected. If there’s an issue, switch off the power again, and double-check your connections.
Now you know!
So, there you have it! You have officially learned how to wire a light switch. Remember, if you're ever unsure about any step, always take a break and consult a professional electrician. Working with electricity can be dangerous, so your safety should always come first.
Found this blog useful? Why not discover more ways that WD-40® can help you around the home?
The uses shown and described for WD-40 Multi-Use Product were provided to WD-40 Company by the users themselves. These uses haven’t been tested by WD-40 Company and do not constitute a recommendation of suggestion for use by WD-40 Company. Common sense should be exercised whenever using WD-40 Company products. Always follow the instructions and take heed of any warnings printed on the packaging.
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