Three Way Light Switch Circuit

With a pair of 3 way switches either can make or break the connection that completes the circuit to the light.

Three way light switch circuit.

The black line wire connects to the common terminal of the first 3 way switch. A 3 wire nm connects the traveler terminals of the first and second 3 way switch together. A three way light switch is different than a traditional single pole light switch as it contains an extra screw to connect an extra wire. In a hallway or large room for example installing three way switches at both ends lets you turn the light fixture on or off from both locations.

Although a 3 way is one of the hardest electrical circuits to figure out it s also one of the most useful. Three way switches can be wired in a number of different ways depending on where they are located relative to the light fixture in the circuit cable runs. Keep reading and learn how to wire a light switch. Typical 3 way switch wiring nm cable in the 1st diagram below a 2 wire nm cable supplies power from the panel to the first switch box.

Three wire cable runs between each switch and the light fixture. There are several ways to install a 3 way light switch. This is known as the common screw and it s usually black instead of brass or silver. A 3 way light switch allows you to control a light source from two separate points.

The whole wiring a light switch project can be completed in a few hours if you don t have to do any drywall removal and repair. A three way wall switch is a common type of light switch that makes it possible to control a ceiling light or other electrical fixture from two different locations in a room. Another dead giveaway of a three way switch is the absence of on and off markings. This might seem intimidating but it does not have to be.

Between each three way switch is a pair of travelers that are connected to the common terminals. So what you should see if you have correct 3 wire electrical cable romex is a black power white neutral and now a 3rd red wire. The hot source wire is connected to the common terminal on sw1. With these diagrams below it will take the guess work out of wiring.

For example they can be arranged so that the feed cable runs to the first three way switch then to the light fixture box then to the second three way switch. Regardless of what 3 way switch wiring diagram you re following you ll need to use a 3 wire cable to connect the two 3 way light switches. Take a closer look at a 3 way switch wiring diagram. Interested in a 4 way switch wiring diagram.

On one of the 3 way switches a line or hot wire gets connected to the copper or black screw terminal.