Light switch

[luke(1)]

I am trying to fit a new light switch but I don’t understand the existing wiring
On the ceiling rose I only have 3 wirers red ,black and earth but at the switch
I have 3 lots of cable
All the black ones are connected to each other and on the switch it has 3 red wires
Two of them in the same connecter is this ok and can I just fit a new switch or do I need a special switch

Thanking you in advance for any help
Luke

 

[Qedelec]

The electrician that wired this has taken the supply to the switch rather than the rose. This is unusual but not unsafe.
The three cabes are feed to, feed from and Switch cable.
You only need a simple one way switch but you can fit a two way also.
Connect the two reds wires to COM and the single red one to L1, or vice versa.

 

[luke(1)]

thank you

 

[slippyr4]

This is unusual but not unsafe

I thought this was becoming increasingly common in new houses with the prevalence of fancy lights such as downlights which have no real facility for making the loop connections?

 

[notb665]

Yes, I believe it is.

 

[ban-all-sheds]

So will Joe Schmoe's confusion move from rose to switch?

Will he put all the reds in one terminal and all the blacks in another?

 

[andy]

will all switches need 25mm boxes and chased in further than the plaster...

 

[Lectrician]

We never use 16mm boxes anyway......

 

[slippyr4]

o will Joe Schmoe's confusion move from rose to switch?

Will he put all the reds in one terminal and all the blacks in another?

will all switches need 25mm boxes and chased in further than the plaster...

Quite probably. I was only asking!!