This is known as the common screw and it s usually black instead of brass or silver.
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 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.
The black line wire connects to the common terminal of the first 3 way switch.
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.
Three wire cable runs between each switch and the light fixture.
On one of the 3 way switches a line or hot wire gets connected to the copper or black screw terminal.
The methods shown here are some of the safest and most versatile though not the only options.
Keep reading and learn how to wire a light switch.
A 3 wire nm connects the traveler terminals of the first and second 3 way switch together.
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.
Between each three way switch is a pair of travelers that are connected to the common terminals.
With these diagrams below it will take the guess work out of wiring.
Three way switch wiring with light middle the source in this circuit is at the first switch and the light fixture is located between sw1 and sw2.
Take a closer look at a 3 way switch wiring diagram.
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.
Pick the diagram that is most like the scenario you are in and see if you can wire your switch.
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.
A 3 way light switch allows you to control a light source from two separate points.
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.
The hot source wire is connected to the common terminal on sw1.
Although a 3 way is one of the hardest electrical circuits to figure out it s also one of the most useful.
There are several ways to install a 3 way light switch.
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.
Another dead giveaway of a three way switch is the absence of on and off markings.
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.