Coast 3-way or California 3-way wiring system

Coast 3-way or California 3-way wiring are a method of connection that can be used for staircase wiring or multiway switching setups.

In this wiring configuration, the first pole of both switches carries the phase line. The common pole and the second pole of the both switches are connected to each other as shown in the below video. Subsequently, the phase connection to the load is established from the second pole. Consequently, the lamp (L1) illuminates if one switch is ON and the other is OFF. Conversely, when both switches are in the same position, the lamp remains OFF.

The Coast 3-way or California 3-way circuit exhibits a pattern, wherein the output is high when both switches are in opposite position. This unique characteristic enhances its versatility for applications requiring control from multiple locations, making it an effective choice for staircase lighting, room access points, and other scenarios demanding multiway switching capabilities.