dimmer 2 way switch.


25 May 2004
Reaction score
United Kingdom
replacing a 2 way standard switch with a dimmer which will control one lamp.

noted the wiring previously used but it doesnt work with the dimmer.

at switch 1 i have(this is the dimmer)
cable1- red and black
cable2- red blue yellow

at switch 2 i have (the standard switch)
cable-1 red blue yellow

The dimmer is called chelsea flat plate range
it has

At switch 1 when the red resides in L1 and black in L2 the dimmer doesnt respond, when the red is in comm and black in L1 or vice versa it does work.

I have tried various combinations from this and some other sites but i cannot for the life of me control the light with both switches.

would be very greatful if someone could help me.

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One way of doing it:

Switch one:

Red to Red (not into switch)
black to COM
blue and yellow to L1 and L2

switch 2:

red to COM
blue and yellow to L1 and L2
The markings on the old switch were very confusing.
your way works great thank you very much

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forgot to mention

1. metal switches must be earthed
2. The yellow, blue and black wires should be identified with red sleeve, or at a push, tape.

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