4 Way Switch Electrical Diagram. In the diagrams below the first switch 3 way common terminal connects to line voltage. The white wire of the cable going to the switch is attached to the black line in the fixture box using a wirenut.
A 3 wire nm connects the traveler terminals of the first 3 way switch and the first 4 way switch. You can avoid costly mistakes. You can have an indefinite number of 4 way switches in a circuit.
A 3 wire nm connects the traveler terminals of the first 3 way switch and the first 4 way switch.
If you understand how to wire a 3 way switch you ll have no issues with a 4 way switch. For complete instructions on wiring a basic 4 way switch see our wiring a 4 way switch article. This diagram is a thumbnail. They all must be between the two 3 way switches.
