Question about Dimmer installation

[mcdtv]

Trying to fit a single dimmer switch - but then when opened up current light switch found:

two red wires
One brown wire
one green/yellow wire.

Instructions say that the red wires need to connect to the dimmer L1 and C connections - this makes sense.

Problem lies when I'm told that the earth wire needs to be connected to the metal plate of the dimmer - that I guess is the Green/Yellow wire.

But where do I then fix the Brown wire?

Confused!

 

[rjm2k]

Photos always help. Does this control more than 1 light?

 

[mcdtv]

No - it's just for one light.

Will try and get pics later

 

[PrenticeBoyofDerry]

Have made a note of where the cables were originally.
If not do you have a safe approved means of testing for voltage.
I would take a guess that the brown has been added to supply another item with a common live, has there been a newly installed switch anywhere near this switch, may a long side or reverse side of wall?

That would then suggest that the two reds where (1) permanent live (2) switch live.
But which is which would be reliant on testing for voltage.

The earth/cpc should be fitted to the metallic switch plate at the earth terminal and if the backbox is metal and do not have at least one rigid screw lug for plate, then that would also require earthing to switch plate.

Is this a replacement for and existing dimmer or rocker type switch? As you will need to confirm the lamps or any transformers are suitable to be dimmed and that the load allowance is correct.

 

[mcdtv]

Hi

No. Basically it's a normal light switch - but I now want to change it for a dimmer switch. There are light switches on the other side of the wall.

When I unscrewed the current switch, the two red wires were connected to L1 and C.

The green/yellow and the brown were both connected to a small plastic block inside the plastic switch box.

will try and take photos later.

 

[PrenticeBoyofDerry]

So that would suggest com is perm live and L1 is switch line to lamp.

Then brown core is concern with regards to colour, possibly someone either trying to make safe a redundant part of circuit or it could be offering continuity to another part of the light circuit, does this brown cable by any chance go directly through wall to reverse of wall switch?
You still need to confirm whether the lamps/any transformers are compatible with the dimmer.

 

[mcdtv]

Have attached the pics of the current socket and its set up and the back if the new dimmer switch.

Untitled

• mcdtv
• 30 Dec 2013
• 1

Untitled

• mcdtv
• 30 Dec 2013
• 1

Untitled

• mcdtv
• 30 Dec 2013
• 1

 

[plugwash]

I don't see any browns in that picture just reds, black and green/yellow.

 

[mcdtv]

Thats right.

I thought it was brown but the camera obviously has brought the black out. My fault!!

 

[PrenticeBoyofDerry]

It's a neutral connection and it is not connected to the CPC/earths, different terminals.

 

[sparkwright]

Leave the black wires as they are.

Connect the green and yellow wires to the earth terminal on the faceplate.

 

[mcdtv]

So basically reda go to l1 and c.. while greenyellow goes to metal plate at back of switch.

And then just leave the blacks where they are?

 

[mcdtv]

Great!!

Thanks for your help!!

 

[sparkwright]

It looks like there's two earth wires within the green and yellow sleeve.

Make sure both earth wires enter the earth terminal. And check first the ends aren't brittle. If they are, cut the very ends off so you have nice strong ends.