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Help desperately needed - replacing light switches

Discussion in 'Electrics UK' started by dirty harry, 22 Apr 2010.

  1. dirty harry

    dirty harry

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    Hi, really need some help please with what I thought would be a simple job!

    I'm replacing three switches that control the hallway and landing light, a 1G 2W in the hall, and 2 x 2G 2W, one at the foot of the stairs and another upstairs. Both the 2G 2W switches control the upstairs landing light as well as the downstairs hall light. This is the existing wiring coming out of the wall at each switch:-

    Downstairs 1G 2W - 1 x Twin core and earth to the ceiling light and 1 x three core (red/blue/yellow) and earth going to the upstairs 2G 2W switch

    Downstairs 2G 2W - 3 x three core and earth - note this wiring has not been touched.

    Upstairs 2G 2W - 1 x Twin core and earth to the ceiling light, 2 x three core (red/blue/yellow)and earth, one from each of the downstairs switches

    Note:- Although the downstairs 2G 2W switch is still intact, the other two switches have been disconnected so I cannot copy the wiring on those switches:cry:

    Simple question, can anyone explain to me how they should be wired up to the COM, L1 and L2 terminals in the downstairs 1G 2W and upstairs 2G 2W switches, because it is driving me insane!! Any urgent assistance would be really appreciated as I must get it finished tomorrow.

    Cheers
     
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  3. Steve

    Steve

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    Difficult one this.

    We need to know what is connected where in the switch still intact (only the one that controls the landing light). This will lead the way.

    You should find one switch has four terminals - this is an intermediate switch, which one is this?
     
  4. dirty harry

    dirty harry

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    The intact switch has 8 terminals, none of which are marked with COM, L, L1 or L2! 6 terminals are taken up with 3 blue and 3 yellow, there is a red in terminal 7 and terminal 8 is empty. The spare two red wires are connected via a terminal block.

    The new 1G switch has 3 terminals, L, L1 and L2, plus the earth (it's a chrome switch). The new 2G switches both have 2 terminals blocks, each with L, L1 and L2 (6 terminals in total).

    Does that help?
     
  5. Steve

    Steve

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    Trying to get my head around this.

    The one with 8 terminals - you NEED an intermediate switch to replace this, a 2 way wont work.

    Anyway the wiring for the intermediate - break it down. The side that controls the landing light, has all 4 holes filled. What is in each hole?

    The 1 gang (1 switch) switch downstairs - only controls the upstairs light? Or the downstairs light?

    Any chance of a few clear photos and captions? Tip: use macro focus on digital cameras to get clear close ups. Macro is sometimes symbolised by a little flower.


    EDIT:
    I think I got it wrong - does the 1 gang downstairs light control the upstairs or downstairs light? And the 3 core from this - Are you CERTAIN it goes upstairs? Or to the other downstairs switch? I have sketched this out and AFAICT it can only control the downstairs light.
     
  6. ColJack

    ColJack

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    easy one..

    red in COM and yellow and blue in L1 and L2 ( shouldn't matter which way but if you find that the switch operates "upside down" then just swap the yellow and blue. )
    and red from 2 core to yellow, black from 2 core to blue
     
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  8. Steve

    Steve

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    OK, this might come in stages.

    Downstairs in the 1G switch RED from the other switch goes to COM.
    blue and yellow go to L1 and L2.

    Connect the black and red to L1 and L2.
     
  9. Steve

    Steve

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    Upstairs you need to connect one of the 3 core to one switch on its own, copying the connections you just made downstairs, blue and yellow to L1 and L2, and red to COM.

    That should see the downstairs light working.

    For the other switch upstairs, copy the wiring from the 1G downstairs again.

    So you have the blue and yellow in L1 and L2 with their RED in COM. And the red and black in L1 and L2.

    That SHOULD work.


    You have two 3 core and earths between the two 2G switches. If you dont know which is which at both ends, you'll need a multimeter.
     
  10. Steve

    Steve

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    Mine is better :p
     
  11. dirty harry

    dirty harry

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    You could be right in that the the 3 core from the single switch goes to the other downstairs switch, not the upstairs one. That would make more sense.

    If I don't have any joy with the tips you chaps have given me, I'll try and upload some photos.

    Thanks for the replies everyone. I'll let you know how I get on!
     
  12. dirty harry

    dirty harry

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    Steve/ColJack

    Thanks for the advice guys - all sorted!

    I have one happy customer (the wife!) thanks to you :D
     
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