light switch wiring query

[diynovice193]

i'm new to this but keen to have a go.

Current light switch was damaged when moving furniture.

Bought new switch but not quite the same as the old. I have four wires, red, blue yellow and green. The new light switch that I bought has three slots for wires and another for the earth.

It is for a single pendant light.

What is the yellow wire? (I am a novice at this!)
The old switch had the blue at the top and the red and the bottom. because the switch was damaged the wiring was displaced! the green to the earth and the yellow?

This I am sure is basic but keen to learn.

Thank you

 

[electronicsuk]

Are there any other switches that operate the same light fitting as this one? If so, chances are that blue will need to go to COM and red/yellow to L1 and L2 respectively, but without test equipment we can only guess.

Did it look as if the yellow used to be connected?

And yes, green/yellow sheathed is the earth connection, or simply plain green sleeving if your installation is fairly old.

 

[sparkybird]

It sounds like a two way switch. If you take off the other switch which controls the same light, carefully, so as not to pull any of the conductors out - then just follow the red/blue/yellow combo.

SB

 

[diynovice193]

thanks for your reply Matthew,

Unfortunately I didn't notice when I dismantled the old light casement so not 100% sure if all wires were connected up previously.
The green/yellow was connected to the casement (as metal/brass) but actually the new one I will now fit is just plastic therefore doesn't look like there is a place for the earth.
It looked like the old switch had red at the top (comm) and the blue in L1 - is this possible. Could this be dangerous or make a difference as the switch worked before it was damaged.

Therfore it looks like I still have a red & blue to connect. Nothing to L2 as only one switch however query above to placing of colours.

Is it possible the green/yellow and the yellow wire are not required and they are just taped up with insulating tape?

Many thanks

 

[electronicsuk]

If you only have a one way switching arrangement then it is indeed possible that the yellow is just there as a spare. You should put the yellow and green/yellow earth each into their own terminal (choc) block rather than taping them up.

 

[diynovice193]

matthew,

many thanks.