Inside A 4 Way Switch

As you will see most 4 way switch wiring is placed between the wiring of two 3 way switches therefore a 4way switch is installed with two 3way switches.

Inside a 4 way switch. The four way switch is not used on its own but in addition to a combination of switches. It is important to understand how these switches are wired before attempting to troubleshoot or replace. A 4 way switch is dpdt inside. Each pair of traveler terminals should be wired to the traveler wires from one of the 3 way switches in the circuit.

4 way switch configurations are used to control lights with three or more switches a 3 way switch is used on each end with one or more 4 way switches in between the two 3 way switches they do not have an on off position like single pole switches. While wiring a 3 way switch is good enough for a staircase or hallway wiring a four way switch is crucial for the addition of a third forth or more switches. The center switch is 4 way switch while the outer two switches are 3 way. 4 way switch wiring comes in real handy when you would like to control a light fixture from more than two locations.

A 4 way switch must be wired between two 3 way switches as shown in the diagrams on this page. They re used like this. When connected properly a simple flip of any of the switches will turn on the light. The 4 way switch is simply crossing the connections or connecting them straight through sort of an xor function.

To illustrate the 4 way switch wiring switch boxes and fixture boxes are not shown but are obviously required for every application. If you only need two switches just connect sw1 and sw2 directly to each other. That page and its links also discuss proper wire colors and several wiring alternatives. A 4 way switch has five terminals.

For a discussion of how to wire such circuits see 3 way and 4 way light switches. Shown above is an animation of a circuit using three switches to control a light.