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[daz2710]

I want to replace a old 3 way light switch with a modern new one.

I have 3 cables,black and red coming out of each one.

The new light switch has at the top L2 L1,common,L2,L1

The bottom has common,L1,L2,common.

The light switch is left side operates the upstairs light with a light switch upstairs,the middle one operates the downstairs light and the far right operates the outside light.
Can anyone tell me how to wire up as the instructions i got are rubbish.

[ericmark]

Each cable will have one wire to top and one to bottom so cable A will likely be Red to L1(top left) and Black to com(bottom left) cable B will likely be Red to com(top middle) and Black to L1(bottom middle) cable C will likely be Red to L1(top right) and Black to com(bottom right). If switch works wrong way around swap L1 to L2.