3 way switch

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Note that in this case, a larger than normal device box is required at switch #1 location, due to box fill calculations (most regular size boxes will only accommodate five wires; in this situation, you will have seven wires).




 

Wiring a 4-Way Switch

The 4-way circuit is used when you want to control the light or lights from two or more locations.  This article and detailed wiring diagram outlines the steps to wiring a typical 4-way switch.

4-Way Switching Circuits

If you understand the logic behind the 3-way circuit, the 4-way will not seem that difficult.

When Do You Need a 4-Way Switch?

The 4-way is used when you want to control the light or lights from two or more locations.

4-Way Switch – NOT To Be Confused With a 2-Pole Switch!

A 4-way switch has four terminals (do not confuse with and purchase a 2-pole switch by mistake).

The 4-way terminals are labeled “In” and “Out” (two of each). The mechanics of this switch are simple, in that they either switch the travellers straight through, or criss-cross them.

To add more than three locations for one set of lights, you would just insert more 4-way switches in between the two 3-ways. The following diagram illustrates the easiest way to connect a 4-way circuit.