Mains Double swtich wiring - Help Please

[S47]

Help please
I have just fitted an external PIR light.
I planned to use a spare switch on an existing internal double switch [only 1 of the 2 switches are used at present]
after removing the front cover - I see on the back of the switch there are 7 connections, the existing light uses A[red wire] A1[black wire] and earth.
This leaves me with connectors marked A2, B, B1, & B2. Which 2 of these do I need to use to wire up the new PIR light, so it works when the 2nd switch is activated.
Thx
Mal

[netherfield]

Live feed to B and lamp to B2,if the switch appears to work upside down transfer lamp to B1.
Earth to existing Earth point.

Looks like the existing black wire ought to have a red sleeve on it.

[Ganglandboss]

No offence but it really sounds like you don't know what you are doing. You need to know where the cables from the spare switch go to - it sounds like there will be a ceiling rose or joint box tucked away somewhere. There will not usually be a neutral at a switch so you're starting in the wrong place. Also the works you are planning are notifiable so they have to be undertaken by an approved domestic installer or signed off by building control.

My advice is get an electrician in.

[shirt]

notify building control to fit a light? come off it, as if anyone does that.

however, the OP doesn't realise he needs more than just a switch for his light, and on that basis i agree he should leave well alone.

[S47]

Netherfield
Thx now sorted
I've done plenty of wiring but this had me baffled??
Mal

[Mr GrimNasty]

You shouldn't really have done that like that (and I'm not talking about part P)!

I hope it is a very low wattage light, else you might need to check you aren't overloading your lighting circuit.

Normally you would wire these up from a fused spur off a ring main.

I'd want it under RCD protection too.

You'd be better off just plugging it into a socket (+ RCD adapter if required), if you can't be bothered.