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1 Gang 2 Way Dimmer - confused?!?

Discussion in 'Electrics UK' started by Adamc, 29 Sep 2005.

This topic originated from the How to page called Replacing a one way light switch with a dimmer switch.

  1. Adamc

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    Can anyone please shed some light as to how I replace an existing 1 gang dimmer which has stopped working with a new 1 gang 2 way dimmer? I thought it would be easy enough following the wiring on the broken dimmer switch, but after reading some of the wiring suggestions on this board, I am now confused.

    The existing dimmer switch and the new one are laid out the same - there are 3 terminals: Comm (the swiggly line with an arrow), L1 and L2. On the broken dimmer, the black wire is connected to Comm and the red to L2. On another topic above, subject, "1 gang 2 way dimmer", someone has told the chap to wire red to Comm and black to L1 with nothing going into L2.

    Being a bit of a novice - what's the right solution? What's the difference between L1 and L2.

    I'm really not too keen on electrocution so if someone could tell me which way is right I'd appreciate it.

    Thanks,
    Adam. :rolleyes:
     
  2. breezer

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    look in the for refernce section for the actual difference, but in your case it will make no difference, but the "norm" is common and L1 when when using a 2 way switch for ome way
     
  3. Adamc

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    Thanks, but which wire into which terminal?

    As I said, on the broken dimmer, it's the black wire connect to Comm, but that other chap said connect the red wire to Comm.

    Which is correct because presumably I'll blow myself up if I connect the wrong wire to the wrong terminal?!

    Thanks for you patience.
    :confused:
     
  4. plugwash

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    both are correct the important thing is you connect one wire to com and the other to either L1 or L2. Generally L1 will make the switch behave the way you expect and L2 will make it behave upside down but this can occasionally vary between brands.
     
  5. Adamc

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    Ok, thanks I'll give it a go.

    BTW, do you know what "switched live" means? On the diagram, it refers to the "live" wire and the "switched live" wire? Is that another name for neutral coz I've only got the live (red) and neutral (black) going into the broken dimmer?

    Thanks.
    :oops:
     
  6. plugwash

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    just because a wire is black does not make it a neutral.

    generally the red core carried the permanent live down from the light and the black core (which should be marked with red sleeving at terminations but usually isn't in practice) is used to carry the switched live back to the light.
     
  7. breezer

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    another name for neutral is not switched live, if it was it would be called neutral.

    i appreciate you are trying to understand, so i will say have a look in for reference section, lots of drawings in there, you will then be able to see what a switched live is / does, and why your statemnt about live and neutral going to the switch is wrong.

    if i told you ther answer you will not learn, have a look at the diagrams, then come back and say what you think the black does in your case (and most others)
     
  8. Adamc

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    Will do. Sorry guys, I'm new to this forum and didn't realise there was a "for reference" part. Didn't mean to drive you mad!

    Thanks for all your help.
    :eek:
     
  9. securespark

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    Doesn't matter which term you use with dimmers - it's the same result either way...
     
  10. plugwash

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    yeah it doesn't matter with push on push off accessories which most dimmers are.
     

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