new light switch has different terminals!

27 Jan 2008
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West Midlands
United Kingdom
Hi, please help if you can! I have a double, one way switch for a hall light and a porch light. The old switch has: top, L1, L2 and Common with a red cable going into L2 and another red cable into Common. There is a bridging red cable going from top common into bottom common and a grey wire going into the bottom L2. There is nothing in either top or bottom L1. The new switch has two separate black terminals boxes, each one has an L at the top and and L1 and L2 at the bottom.

Not sure what goes where on this new switch!
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L is the same as com, obviously L1 and L2 are the same as before.

You will probably find that on the old switch that each set of terminals is arranged in a triangle formation, with com being at one end and L1/L2 at the other. Because the old switch is two gang there will be two of these sets of terminals, and one will be vertically flipped - just bear that in mind when wiring the new one so that you don't get your switches mixed up.

I'm sure some kind soul will have a picture that better explains what I'm trying to describe here!
Thanks for quick reply. However, still a little puzzled.

Based on your explanantion, I assume I put one red cable into the L on the one black box, and then bridge to the other L on the other black box (to replicate the common set up on the old switch). That leaves me with an L1 and an L2 on each of the two black boxes. I have one red cable left and one grey cable, which of these do these go into?

Sorry to be dim but I am new to this!
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Thanks very much. You solved my problem and the switch is in and working. Very much appreciate your time and trouble.

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