How to Add a Switch to an Electrical Cable

If you have an electrical cable attached to a lamp or appliance without a switch on it, then you might be looking for an easier way to turn the appliance on and off. One of the simplest ways of installing a switch is to fit an in-line switch between the appliance and the plug.

In-line switches are very easy to install because they are self contained units, which are very safe to use. With a bit of basic electrical knowledge, you should be able to safely and easily install these.

Step 1 - Choosing a Switch

When choosing a switch, make sure you pick one that is appropriate for the job. If you want to use the switch to control AC electricity, then you will need a switch which is capable of controlling 110V safely. Also choose a self contained switch which doesn't need any cases, as these will be safer and much easier to install.

Before working on an electrical switch, you should unplug the lamp or appliance from the wall. Unplugging the appliance will ensure that you don't get shocked when working on it.

Step 2 - Cutting the Wire

All switches work by interrupting the connection on the electrical wires. To make this possible, you need to cut the wire in two so that the switch can be placed in the middle. Cut the wire where you want the switch to be located carefully because after you've made the cut, you're committed.

Step 3 - Opening the Switch

Most in-line switches are held together with a small screw on the back. Removing this screw will allow you to open and take apart the casing. Once the case is open, you will be able to see the terminals and connections inside the switch.

Step 4 - Wiring the Switch

The live wire is the wire that you should be switching. There should be three connections on the inside of the switch. Depending on the type of switch you bought, either both of the wires will be switched, or only one will be switched. The others will be connected together through the switch.

Loosen the terminals using an electric screwdriver, then strip the ends of all the pieces of wire. Twist the wires and make sure they're neat, then push them into the terminals and tighten the screws. Give the wires a pull to ensure that all the connections are nice and tight. Also ensure that there are no stray strands of wire, which could short the circuit.

Step 5 - Clamping the Wire

To prevent the wires from being pulled out of the switch, they should be clamped. There should be two clamps on either side of the switch, which can be screwed down over the insulated section of the cable. Try to make this as tight as possible to make sure that the wire is securely fixed.

Step 6 - Testing

Now you just need to plug the appliance back into the wall and check that the switch works. If anything trips your circuit breaker, then there's a good chance that something has been connected incorrectly or that you're using a faulty switch.