4 Way Switch Diagram. The white neutral splices to the white to the light. The black line wire connects to the common terminal of the first 3 way switch.
This diagram is a thumbnail. A four switch configuration will have two 3 way switches one on each end and two 4 way switches in the middle. Watch the 4 way switch video below and pay attention.
Keep in mind that each light switch will count as two wires when calculating your box fill.
4 way switch wiring diagrams national electrical code. Click here to access note. Typical 4 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. At the center box with a four way switch black and red from the first box goes to two terminals with the black and red going to the third box to the other two terminals.
