1 way 2 gang dimmer switch - one gang switching both on/off

[Kieran3001]

Hi all.
I removed an old 2 gang (1 way) dimmer switch. When I removed it, a wire fell loose during removal so I was not able to exactly copy the pre-existing wiring.

Gang 1: I have a light wire going into L1 and the green/yellow wire going into C.

There is a linking wire between the two Cs.

Gang 2: I have light wire going into L1 and the other part of the green/yellow wire going into L1.

However, Gang 2 is switching all of the lights on and off in the room.

Does anyone have an idea of which wire might be in the wrong place? Let me know if I have missed any info out that would be useful.

 

[ETAF]

pictures would help , BUT Green/Yellow is often used as an Earth

 

[opps]

I am not an electrician...

I would recommend turning off the MCB, loosening the ceiling roses and using a multi-meter to check for continuity between each of the wires there to the switch to identify them.

In the past I have used cheapo telephone cable from the rose to near the switch because the leads on the multimeter are so short.

 

[flameport]

green/yellow wire going into C.

Green/yellow is the protective conductor / earth.
What you have described is a dangerous mess.

Please add photos of the switch and wiring.

 

[Kieran3001]

Hope this helps. The green yellows wire goes into grey and then out as a red wire.

 

[flameport]

It's not working because you have mixed up the red wires.

The rest of your descriptions about the green/yellow wires makes no sense at all.

 

[Kieran3001]

Thanks. That's what I was thinking. I've lost track of which wire is which.

The red wires which come out of the grey casing with yellow/green wire going in - do these need to go into the Cs?

And then the remaining two red just go into the L1s?

 

[bernardgreen]

The red wires which come out of the grey casing with yellow/green wire going in

The red wires go in the grey sheath and then continue as red insulated wire all the way to the other end of the sheath which is almost certainly at the ceiling rose.

The green/yellow do the same except that the wire is bare copper inside the grey sheath with the green/yellow sleeving where the bare copper wire comes out of the grey sheath.

 

[Kieran3001]

The red wires go in the grey sheath and then continue as red insulated wire all the way to the other end of the sheath which is almost certainly at the ceiling rose.

The green/yellow do the same except that the wire is bare copper inside the grey sheath with the green/yellow sleeving where the bare copper wire comes out of the grey sheath.

Thank you. So the wires that go into the grey sheath - should I put those into the L1s?

and the two remaining wires in Cs…?

 

[bernardgreen]

Please get an electrician to sort the matter out. From what you have posted

and the green/yellow wire going into C

it is likely that the safety Earthing is incomplete.

Putting the green/wire into any of the terminals on the switch will create a dangerous situation. Least harm is the fuses/MCB will trip. Worst is that items will become Live because you will have connected the safety Earth wire ( the green/yellow wire ) to the Live supply and not to Earth as it should be.