Double Gang Switch Replacement; Comm L1 Link?

[James Adkins]

Hello Everyone.
Im struggling to replace a switch in my flat with a dimmer; I'm hoping someone on here might be able to help. I currently have a double switch that controls both some roof lights and a 5amp lighting ring. The Lighting ring has a secondary switch on the other side of the room. I never use this switch so what I would like to do is remove/disable it and replace the double main switch with a double dimmer.
Here is where I'm lost. Currently on the side of the main switch that controls the 5amp circuit is a cable that links Comm & L2. This is throwing me a little as I thought on a double gang L1 & L2 where the main and switched cables. I just need the live and switched live for the new dimmer but as nothing is labelled in the wall I can't work out what is what. I have attached a picture of the wiring and here is a description of what is connected to what.

Comm - Red + Red (link to L2)
L1 - Blue + Yellow
L2 - Red + Red (link to comm).

Thanks.

 

[Taylortwocities]

I am struggling to understand what your wiring is.

Need a much better photo of the wiring on the switch
Your wiring layout

Comm - Red + Red (link to L2)
L1 - Blue + Yellow
L2 - Red + Red (link to comm).

Does not make sense. On that plate there are two separate switches. Let us call them A and B.
Each switch will have COM, L1 and L2

What wires go to what terminals? {I can see one, maybe two, blue wires involved there and you have not mentioned them!}

Also, How is the switch in the other room wired?

 

[James Adkins]

Thanks for the quick response. I have sketched out a diagram of how the switches are connected. Im not sure on what colour goes to where after leaving the back boxes. This is drawn as if you are looking at the back of the switch.

 

[EFLImpudence]

Bear in mind the two switches are triangles of Com,L1 & L2.

Not across the top and across the bottom.


Your diagram doesn't make sense; have you drawn it correctly?

Edit - beg pardon - yes it does.

 

[EFLImpudence]

What did you want to know?

It would be more logical to put all the reds in left L2 but it doesn't make any difference.

 

[EFLImpudence]

...and at the single switch the yellow should go to Com;

the other two don't matter apart from the switch may work the wrong way round.

 

[EFLImpudence]

 

[EFLImpudence]

 

[James Adkins]

Thanks for the advise. I know its stupid but I didn't realise it was a triangle thats where I think I was going wrong. I could never get an accurate reading off my volt meeter before but will try again tonight. Hopefully know I can work out which wires go to the other switch!

 

[James Adkins]

What I'm trying to do is bin off the single switch all together (as its behind a cabinate). Then replace the double switch with a double dimmer. I was unsure before however which cables went to the other switch

 

[EFLImpudence]

Yes you can do that.

Just remove the R,Y,B that come from the single switch.
I would put all three in a single connector block and position safely out of the way.
You never know, they may be wanted in the future.

 

[Taylortwocities]

Yes you can do that.

Just remove the R,Y,B that come from the single switch.

And remove the corresponding RYB from the LEFT HAND SIDE of the double switch.
Then move the yellow that is in L2 to L1
And move the two reds that are in L1 to COM

Having done that, and checked the lights still work (!) you can replace the switch with a dimmer.

I could never get an accurate reading off my volt meeter before but will try again tonight.

Don't worry about the meter, hopefully you will not need it now

 

[EFLImpudence]

And remove the corresponding RYB from the LEFT HAND SIDE of the double switch.
Then move the yellow that is in L2 to L1
And move the two reds that are in L1 to COM
Having done that, and checked the lights still work (!) you can replace the switch with a dimmer.

...but not necessarily in that order.

 

[Taylortwocities]

OK Mr Picky

And remove the corresponding RYB from the LEFT HAND SIDE of the double switch.
And move the two reds that are in L1 to COM
Then move the yellow that is in L2 to L1

Better?

 

[EFLImpudence]

Ah no, but yeah.

I thought you meant see if the lights worked as two-way after removing the R,B,Y.

Sorry.