DIY Doctor

3 way dimmer wiring issue

Postby sadjonvee » Tue Aug 05, 2008 12:25 pm

I have a dimmer box with THREE dimmers on it. I have to replace the dimmer units, and rewire.

Each unit has wire points labelled L1, L2 and C for wires.

I have FOUR black wires coming into the box from the wall.

I have TWO wires which linked the dimmer units together.

In the original configuration, callling the right unit RR, the centre unit CC and the left unit LL, here's the setup:

Wall to RR L1
Wall to CC L1
Wall to LL L1
Wall to LL C
Internal wire RR C to CC C
Internal wire CC C to LL L2

If I use this configuration, the light on LL works, and the light on RR works ONLY IF LL is OFF ! CC does not work at all!

I feel really dumb but can anyone help me with this please? It's driving me nuts!


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Simply Build It

Postby sparx » Tue Aug 05, 2008 8:52 pm

Hi all 3 coms should link together no L2's should be used!
seems you have link from cc C going to LL L2 instead of to LL c
This set up works thus :
wall to LL C is live to all switches linked at each C term and L1's are feeds to each light .
So again looking at you run list the last line is wrong, last bit should be -
LL C [not LL L2]
However reading your what works bit makes me think you've got wiring completely mixed up!
If changing wires as I suggest doesn't make everything work then you have got to go back to basics!
One of the 4 cores coming from the wall is the live one, you need to locate which it is by whatever method you have to hand {don't tell me!!!}
Once located & marked it goes into one of the end sw C terms [RR or LL]
then links go from it to the other 2 C terms. this gives a live to each switch.
next put any one of the other wires from the wall to any sw L1 term.
repeat twice more until all cores in terms with NONE in L2 terms.
switch on and see which switch operates which light,
It is now a simple matter of changing around the cores in the L1's until correct order is obtained,
Hope this helps.... I'm goin' down the Pub!!!!
regards SPARX
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Postby sadjonvee » Tue Aug 05, 2008 10:19 pm

LOL !!

Thanks Sparx - glad to see I brought a small measure of enjoyment to your evening - tho' probably less than the pub visit did!

I'll rearrange the wires as per your suggestion and see if I can bring light to the huddled masses in my kitchen!

If I'm successful I'll post a note - if I'm not, well you'll probably just have to put up with a short-lived smell of fried idiot in North London.


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