Changing light switch on wall



Hi Guys,

I hope you can help put my mind at ease. I had an old light switch which was here when I moved in which was cracked, so today I decided to replace it. I bought and identical looking one from B&Q and took the old one off the wall. The old one had two sockets, top and bottom. Top was wired black, bottom red.

The new switch may look the same, but instead it has four sockets, two top and two bottom. They are labelled: L1 & L2 on top and L3 & L4 on the bottom.

The diagram that came with indicated I should put the red wire into L1 (top) and the black into L4 (bottom) and although this works fine it seems kinda odd - I even tested by putting black into L3 and this worked fine too.

So - does it make any odds which goes where? Or is there a correct way of doing is? Or have I got the wrong switch altogether? B&Q certainly seemed to have no other ones (this is the simple plain white switch).


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Doh! I have resolved this issue through research. Seems I inadvertently purchased an intermediate light switch from B&Q instead of a 1-way switch. Consequently I was trying to connect a 1-way connection to a switch designed for being the intermediate between 2 switches.

Whilst it worked alright, I felt better by removing it and replacing it with the correct 1-way switch.

We live and learn!
31 Mar 2006
Reaction score
United Kingdom
There is actually no problem at all using an intermediate switch for one way or two way switching, other than the fact intermediate are more expensive.
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Don't I know it! £3.76 for an intermediate compared to 78p for a 1-way! Still, as I'm not that experienced, it's better to be safe than sorry!

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