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[sallybash]

Hi, can anyone help?
I am trying to connect up a two-gang switch in the hall which controls two lights, one in the hall, one on the landing. There is another switch on the landing which is still wired up. It has one (feed) cable, red, black and earth, and two other cables, red, yellow, blue and earth. One of these uses only the red and yellow - the blue is just hanging around in there. The other is wired in. Behind the switch in the hall there are three cables, all of them red, yellow, blue and earth. How do I wire this up?

sallybash

[ericmark]

With two way switching if the switch is marked com L1 and L2 (Some are L1, L2, and L3 in which case com = L1 etc) The switch wires go to L1 and L2 but in single way switching the switch wires go to Com and L1.
So with first switch of two way pair there will be tow wires in L1 and L2 and one wire in com. There is no colour code (Really all wires should be red [old] or brown [new]) but the three core cable will have same colour in each hole so if you have a yellow in com on one switch it must also be yellow on second switch. As long as the com is same colour the other two do not matter so much.

I am sure there is a page under projects which has diagrams.