3 way light switch using a two wire control
I’m including this method for reference in case you find it used in your house wiring but would not recommend this approach in a domestic environment. If you are adding wiring for a three way light switch then use the 3 wire control system.
I have detailed, quite extensively, why a two wire control system can be problematic in the article 2 way switch with 2 wire control. All the issues raised there apply here too, especially if used in stairways and the switches are on different floors.
This method is best suited to conduit/trunking based installations where single core conductors are used.
3 way light switch schematic diagram using a two wire control
Tags: 3 way lighting circuit, 3 way switch, 3 way switching (UK), circuit, electrical wiring, how to wire a light, how to wire a three way switch, intermediate light switch wiring, intermediate switch, Light wiring diagram, lighting circuit, lighting wiring diagram