Help with wiring a 1 gang 2 way dimmer switch

Discussion in 'Electrics UK' started by Stephen369, 28 Dec 2008.

  1. Stephen369

    Joined:
    28 Dec 2008
    Messages:
    4
    Thanks Received:
    0
    Location:
    Manchester
    Country:
    United Kingdom
    Hello,

    I was hoping someone could help me with wiring a 1 gang 2 way dimmer switch. The dimmer has 3 connectors (L1, L2 and COM). From reading the other posts I understand these to be on-way, two-way and common. The Wires from the wall are 2 red, 1 black and one earth. These wires come from 2 main sheaths.

    I have had a look at the other connected socket (not a dimmer) and it has 1 red in L1, 1 red in L2, then 1 black in a second L1 and one black in a second L2. Earths are connected.

    I have currently got the dimmer set up as Black in COM, red in L1 and red in L2 but this doesn't work. Please could someone advise of the correct combination? I'm not really bothered which switch turns the light on, provided something does.

    Many thanks in advance.

    Stephen
     
  2. Spark123

    Joined:
    2 Jun 2005
    Messages:
    14,378
    Thanks Received:
    424
    Location:
    Cumbria
    Country:
    United Kingdom
    How was the old switch connected?
    2nd L2 sounds like it could be a 2 gang switch hence will have 2 of each Com, L1 and L2, possibly a link wire between two connections??
     
  3. Stephen369

    Joined:
    28 Dec 2008
    Messages:
    4
    Thanks Received:
    0
    Location:
    Manchester
    Country:
    United Kingdom
    Hi Spark123,

    Apologies, but I realised a mistake in my thread when I was leaving the house yesterday. It's actually a 3 way connection. Here's the deal:

    One ceiling light upstairs with a 1 gang switch (as described previously with L1 L1 L2 L2), a 1 gang dimmer (as described previously with L1 L2 and COM which I can't connect up). and now a 2 gang switch downstairs (not looked behind this yet). None of the switches will operate the upstairs light (bulb fine!!)

    I know it's a time old mistake, but I really can't remember how the old switch was connected. I just didn't think it would be so complicated.

    Does this new info shed help in any way?

    Kind Regards.
     
  4. ban-all-sheds

    Joined:
    27 Aug 2003
    Messages:
    51,092
    Thanks Received:
    1,999
    Location:
    London
    Country:
    United Kingdom
    There are different ways to wire up 3-way light switching, but by the sound of it yours is like the top diagram here:

    http://www.diynot.com/wiki/electrics:intermediate

    BTW - you do know how a multi-way system will work when one of the switches is a dimmer?
     
  5. Stephen369

    Joined:
    28 Dec 2008
    Messages:
    4
    Thanks Received:
    0
    Location:
    Manchester
    Country:
    United Kingdom
    Thanks for your response ban-all-sheds.

    From what you've said and studying the diagrams, this seems to make sense. I'll try this.

    With ref to your last question, I was assuming that the dimmer acts as a normal switch (on/off) - pushing to switch on/off and twisting for dim/bright. I'd appreciate further help if my understanding is incorrect.

    Many thanks.
     
  6. ban-all-sheds

    Joined:
    27 Aug 2003
    Messages:
    51,092
    Thanks Received:
    1,999
    Location:
    London
    Country:
    United Kingdom
    Wherever you switch the lights on they will come on at the brightness level set by the dimmer.

    So if you turn them on downstairs and they aren't at the level you want you'll have to walk upstairs to turn the knob on the dimmer.
     
  7. Stephen369

    Joined:
    28 Dec 2008
    Messages:
    4
    Thanks Received:
    0
    Location:
    Manchester
    Country:
    United Kingdom
    Yes, I was aware of that thanks b-a-s. That's just how I'd like it work.

    Next time I'm there I'll try according to the pics and let you know how I get along.

    Thanks again.
     
  8. ban-all-sheds

    Joined:
    27 Aug 2003
    Messages:
    51,092
    Thanks Received:
    1,999
    Location:
    London
    Country:
    United Kingdom
    Fair enough - it's just that some people think that if they turn the lights on from a switch and not the dimmer that they'll come on fully.
     

Share This Page