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Light Switch no Longer Working After Wall Light Change

Postby Wellsy10 » Wed Nov 08, 2017 8:12 pm


I have two sets of lights in a room. Two wall lights operated by one switch and two ceiling lights operated by a separate switch. I changed the wall lights and they worked fine. I have since taken down one of the ceiling rose's and there were three separate cables each with L,N and E. Stupid me didn't note what went where. I have now put up the new rose and the light stays on permanently. The second ceiling light doesn't work at all (this only has the one feed to it). I believe I have identified which cable is the switch/live using a multimeter. I have swapped the wires around numerous times to test if any other combination works, however the current way I have them keeps the wall lights working. If I change it around, sometimes the wall lights dont work at all and sometimes all the lights flicker. Does anyone know what I have possibly got wrong? I have very basic knowledge of electrics but am a fairly competent DIY'er.
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Simply Build It

Postby Mr White » Thu Nov 09, 2017 6:12 pm

You ask "does any one know what I have done wrong"
Well the answer has to be "Yes, I know, you have wired it incorrect" But that doesn't help you.
Now the bad news, with any wiring there is no guide as to which wire / cable should be connected to what, so its not possible to say put this there and that one there and Robert is your mother's brother, what I suggest you do is Draw how it should be wired on a piece of paper then check with your meter what cable does what (You have found the switch cable) and then connect it acording to your drawing.

Look at it the other way, it was ok before you touched it, so everything must still be there, all you have to do is find it.
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Postby ericmark » Thu Nov 09, 2017 7:50 pm

Forgetting about earth with is normally under a clamp, the standard ceiling rose has three sets of terminals, two are switched line, then centre three terminals are permanent line, then finally three terminals which are neutral.

Where twin and earth cables are used it is common for the switched line to be same colour as neutral, in theory it should have sleeving to show it is line, but in practice often the sleeving is missing.

Unless one is careful it is easy to end up with a switched live wire getting mixed up with neutrals and as a result bulbs at half brightness fuses blowing etc.

I tried to once to lead some one through the testing and got kicked of this site for my troubles, so sorry you will have to work out how to test wires.
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