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very odd wiring to light switch....help!

Discussion in 'Electrics UK' started by angularbanjo, 24 Feb 2021.

  1. angularbanjo

    angularbanjo

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    Hi

    I'm in the process of decorating a room and as part of that am swapping out the old white plastic switches and sockets for chrome ones. Most are straightforward, like for like with obvious neutral, earth and live wires but this light switch has got me puzzled. Why are all the wires red, surely it's not all live? We have a 2 gang light switch next door in the lounge which has the same setup but just even worse.

    As you can see from the photo, the solitary red wire goes into L2 and the 4 bunched red wires are all squeezed into the connector at the top. I'm trying to fit a modern 1 gang switch with 4 connectors: Com, 1 Way, Loop and 2 Way. Can anyone suggest which ones I connect to in the new switch? I assume it will be the same idea, the 4 bunched reds into one and the single red into another but which ones?

    Also, just out of interest, why might the switch be wired this way (The house was built in the 1970's)

    Thanks in advance
     

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  3. AndyPRK

    AndyPRK

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    A normal 1 way switch will do. (or 2 way)

    Make sure there is an earth (green) connection in the back, otherwise you should NOT fit metal switches
     
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  4. oceansoul

    oceansoul

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    Stop and think about that for a moment. What does a switch do? What happens if you join live and neutral together?
     
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  5. ETAF

    ETAF

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    Often light switches do not contain a neutral, the Black or Blue wire will Live or the Live Switch return and should be sleeved/marked Red or Brown

    Are those reds, going into another cable outer sleeve ?
    can we see a picture of the cables from the wall

    How many lights controlled by this 1 switch ?
     
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  6. angularbanjo

    angularbanjo

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    Thanks for the replies

    The switch controls one ceiling light. There is an earth in the back box which you just might be able to make out in the attached pic. eta, here's a pic of the cables from the wall, cheers
     

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  8. terryplumb

    terryplumb

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    Your earth conductors should be connected to metal switchplates earth terminal. If you have changed to metal switchplates ,and have not done the above you should do so .
    The 4 bunched reds go to Com ,and the single red to L1
     
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  9. angularbanjo

    angularbanjo

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    Again, thanks for the replies, especially the ones regarding earthing the metal switchplate!
     
  10. angularbanjo

    angularbanjo

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    One final question. I'm assuming that the green/yellow wire I can see in the backbox is the earth which means that the backbox is earthed. In order to make the new metal switch safe is it okay just to run a fly wire from the earth terminal on the back of the new metal faceplate to a suitable spot on the metal back box?
     
  11. EFLImpudence

    EFLImpudence

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    Yes.
     
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