

Three-way switches are commonly found at the top and bottom of a staircase, in garages that have two entryways, on either end of hallways, and any other locations where two separate switches control one light or fixture. A white wire connected to a traveler terminal is hot, and should be marked with black tape to indicate that fact.

The other two terminals are interchangeable, so they do not need to be specially marked, as they can go either way. When replacing a three-way switch, mark the wire attached to the COM terminal before removing the old switch. For safety reasons, it is essential to remember that travelers are always hot wires. The hot wire which originates from the power source connects to the common screw terminal (typically marked “COM”). The terminals are known as common, travelers and interchangeable. The three-way switch features three terminal screws. These switches necessarily do not include on/off markings, as the positions will change as the switches are used. They allow the control of a light or receptacle from two different locations in the room, such as at two different entranceways. Three-Way Switch: Three-way switches are always utilized in pairs.Most single-pole switches also feature a ground terminal for connecting the circuit’s ground wire. The first brass terminal is designated for the incoming hot wire from the power source the second is for the wire going out to the supported fixture. A single-pole switch has two brass-colored screw terminals that are connected to the hot wires. Single-pole toggle switches often exhibit “on and off” markings which are not found on other switches.

It is utilized to control a light, receptacle, or other device from a single location.
