3 light dimmable 2 way gang 400w switch

5 May 2014
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United Kingdom
Before I install replace my light, I need to confirm. I can achieve what is expected. We previously had 3 lights in the living room working off a 2 switch push on off switch.

I have bought 3 dimmable lights and a 2 way 2 gang 400w dimmable switch.

This switch has 2 x com l1 and l2 inputs. I have identified which wires connect each light and earthed the earth wires.

What is the correct configuration to have 2 light run off one switch and a separate light run off the other gang?

I'm thinking 1 into com, 1 into l1 and the other light switch plugged into l2 on other gang?

Many thanks in advance for your advice.
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If you have a two gang/two way switch I would expect 2xcom, 2xL1 and 2xL2,
on the switch plate.
Does each light fitting (3 in total) have it's own conductors at the switch?
If so what coloured cores have you for each?
If not what do you have?
On a two way switch used as two way switch the line supply and switch wire go to L1 and L2.

On a two way switch used as on/off switch the line supply and switch wire go to L1 and Com.

With a two way switch the other switch of the pair is wired like for like so Com to Com, L1 to L1, and L2 to L2.
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Any help would be great on how I can install the dimmer with 1 switch operating 2 lights and the other on its own?
In the main when wired for two way you have red, yellow, blue with green/yellow sleeve on earth. The colours help to trace but in theory yellow, and blue should sleeved red so there is no set system saying where the colours go.

There was also an old system where the live was borrowed from another switch although now frowned on as it causes interference and can also lead to borrowed neutral.

I will guess you have the old two wire system but there is no easy way if you don't know where the cables go you have to ring them out.

So please a little more info what was there what have you done. How is it you don't have what the wires did from old switch.

Shown above is the basic circuit diagram for two way switching.
I've sleeved the green yellow together wires together as well as the blue and left the red. I've got 2 reds going into l1 l2 on one switch and where should the other red go on the other switch please
The two lights on gang one switch=
*2 reds at com/L
*2 sleeved blues at L1
The gang two switch
*Red at com/L
*Sleeved blue at L1
Thank you, just tried this and light 1 and 2 came on with dimmer but when I turned on light 3 which is on the separate gang the fuse shorted.

Now the lights will not switch on.

Any help would be great. Thanks
When you took the old switch off did you make a note of what went where?

Reds and blues is an odd combo - are there no yellows at the switch position?

And before you worry that the switch wiring is incorrect, are you sure there is no short circuit at the light fitting controlled by it?

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