On the switches, the common terminal will be identified by a label and/or the terminal screw will be a different color than the other two.
Article shows you a simple technique for adding a second switch to a stairway light or a light in any room in your home.
Add the switch, youll use one of two wiring diagrams, depending on whether the power comes to your light switch first (the most common situation) or to the light fixture first.
How do i install a three way light switch
In most cases, the existing electrical box will be too small to contain the additional wires and connectors needed for the three-way switch (see sizing the box, below, to find out).
Sure to wrap black electrical tape around the ends of all white wires that are used as travelers between the three-way switches.
Three-way switch is a handy convenience to control a light from two locations, such as at the top and bottom of a staircase.
How do i wire a three way electrical switch
Two wires attach to brass screw terminals, which are usually at the top of the switch, and an additional wire attaches to a dark-colored (not green) screw terminal, which is usually at the bottom of the switch.
Drill holes as needed in the framing and fish a new cable through the wall back to the old switch position.
Add a second switch, find the easiest way to run a new cable from the existing switch to the best second switch position.
With these, you'll have the convenience of turning a light on and off from two spots.
With a pair of three-way switches, either switch can make or break the connection that completes the circuit to the light.
Three-way switch has at least three wires, and possibly four, depending on whether it has a ground wire.
It covers running new electrical cable and connecting both switches, and replacing undersized electrical boxes.
Off power at the main circuit breaker panel before unhooking the existing switch, then check the wires with a voltage detector to verify that the power is off.
Possible, start at one switch location, run the cable straight up through the stud cavity in the wall to the attic, then come back down through the wall to the second switch.
The 14-3 cable has three insulated conductors: white, black and red (plus a bare ground wire).
You'll run cable from the existing switch to this new switch location, so look for the most accessible path between the two (figure a).
Ideally, both toggles should be in the up or down position when the light is off.
Power comes to the light switch, then to the light fixture and the other light switch.
The wiring is more complicated than a traditional single-pole switch, but we'll explain how to make the connections.
And remove the switch plate; then use a voltage tester to make sure that the circuit is dead.