Wiring two-gang dimmer switch

[DeeDubya64]

Hi, I hope someone can help, I have looked through the help topics on here but have been unable to find a solution.

My two gang dimmer switch for the lounge was broken (casing cracked) so I bought a replacement which matches the old one exactly except the 'C' terminals inside are marked with a wavy 'X' on the new one.

I noted where the wires went into the old one before removing it and have wired the new one exactly the same.

However it's not functioning correctly; one of the lights works perfectly but the other will only turn on very dim no matter how I adjust it. I can swap the wires over and get the reverse effect on the other light.

I have mapped out the wires and colours as per the image (hopefully) attached below. This does not show the yellow/green earth wire that is attached inside the casing.

If anyone can tell me where I'm going wrong some advice would be greatly appreciated, otherwise I will try and get someone with some knowledge round to have a look!

Cheers

Untitled

• DeeDubya64
• 21 Jun 2012
• 1

 

[ricicle]

Move the reds into the X's. Yellow into L1 on one side. Blue into L1 on the other side.

 

[DeeDubya64]

Smashing thanks ricicle, will give it a go this evening.

Strange, I was careful to note down exactly what went where before replacing. Maybe I had a moment...

Cheers

 

[Spark123]

Could be you just bought a faulty dimmer switch.
When you say you swopped the wires over do you mean you just swopped the blue and yellow?

 

[DeeDubya64]

Okay I tried your advice ricicle and it's just the same result; one light will only go on very dim while the other works fine.

I also tried putting the old switch back on, and this works perfectly. Although not an option to keep using this as the case is cracked and is probably very dangerous.

Spark - yes that's what I did, and also tried swapping the L1s over.

I had a look inside another two gang dimmer switch I have upstairs, and this has a completely different wiring set up (there is no wire connecting the two L1 or X terminals - there is a brown wire going into each L1 and a blue into each X).

I'm wondering if this particular model of switch I have bought does not work with this wire set up - is that a possibility? Otherwise could be a faulty switch as you say...

 

[ban-all-sheds]

That one upstairs isn't part of 2-way switching with the one you're trying to replace, is it?

 

[DeeDubya64]

No totally different circuit/lights. I just wanted to see how that one was wired.

 

[ban-all-sheds]

It was a daft Q anyway - you already had a dimmer there....

And it's in the lounge so why would you have 2-way switching from upstairs....

 

[ban-all-sheds]

I can swap the wires over and get the reverse effect on the other light.

Which rules out everything except one of the dimmer modules being faulty.

I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.
I must read posts more carefully.

 

[DeeDubya64]

Okay I guess my next option is to try swapping out the upstairs dimmer switch, which is the same model as my new one and definitely works, and seeing if that works with the downstairs. If it works properly, then I had a faulty switch. If it's the same result then that model just does not work with the wiring setup downstairs for some reason and I will bite the bullet and get someone clever to have a look.

Elementary. Innit.

More on this exciting story as it unfolds...

 

[ban-all-sheds]

I'm covering myself with glory today

Before you do anything else, try replacing the short length of red wire which links the two modules with a new piece.

 

[DeeDubya64]

Thanks all, I got there in the end - it was a dodgy switch. Taken it back and got a new one, all working perfectly.

Cheers

 

[securespark]

Most excellent, dude!