A double switch has 2 switch levers in a single housing. You are able to control two light fixtures or appliances from one electrical box. The most common pairing is 2 single pole switches or 1 single pole switch and 1 three way switch.
In most cases, both switches are powered by one circuit. The power from the service panel is connected to the side of the double switch with the connecting tab. This is a metal tab that connects two screws on one side of the double switch. Many manufacturers will have dark colored screws on this side of the switch.
In a small amount of homes, you may have two circuits feeding a double switch. In this case, the connecting tab is broken off with needle nose pliers to separate the switches. If you have a switch that is powered by two circuits, you must break off the connecting tab on the new switch.
When removing the old double switch, mark the wire going to the side of the switch with the connecting tab with a piece of masking tape so you connect the correct wire to the new switch. If you have disconnected the old switch and do not know what wire to connect, you will have to test the wires with an electrical tester to find the wire coming from the service panel. After checking the wires, turn off the circuit to the switch.
Depending on which switch you want to operate a specific light or appliance, you would also want to mark these wires before connecting the new switch.
A switch is just a break in the hot, so there are no neutral wires connected to a switch. You will have power coming from the breaker box into the side of the switch with the connecting tab and hot wires going to each light or appliance from the screws on the other side of the switch.
Always turn off the breaker or remove the fuse to any electrical circuit you are working on.
For more tips, visit the Villa Park Hardware at 46 S. Villa Ave. Villa Park, IL 60181 or online at http://www.villaparkhardware.com.
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