Lighting on end of smokes

[kingeri]

Been asked by a neighbour to change all white accessories for chrome ones and put up new fancy light fittings in their 3-storey house. Whilst doing some quick testing on the (newish) lighting circuits I found the circuit supplying the top floor lights is a bit odd, there are 5 wired interlinked smokes in the property and on the end of the smokes the top floor lighting has been branched off. Never seen this, it's not something I would do and just wanted opinions on it. The circuit is in good order, Zs are fine so although (to me at least) it's a weird thing to do, I can't say that it doesn't comply in any way.

 

[hightower]

Can't speak from experience, but surely this is just the same as the reverse, having smokes branch off the lighting. So long as all the cables meet the requirements (ie smokes not downsized) I too can't see the issue, but as I've said this is my 2 cents of inexperienced babbling.

Only thing I can think of is splitting the lighting circuits, but if it's only the upstairs lights that share the smokes circuit, surely this is the same as the smokes sharing the upstairs lighting circuit?

 

[kingeri]

Thanks hightower. I was initially concerned about voltage drop as the circuit is fairly long, but it's wired in 1.5 so that is fine.

 

[telectrix]

as long as those smokes are connected into a "frequently used" lighting circuit........

 

[kingeri]

as long as those smokes are connected into a "frequently used" lighting circuit........

Hi tel, yes that is a good point. The top floor has two occupied bedrooms so I think that qualifies.

 

[hightower]

When I think more about it, it's probably been done to save cable (if you need to run 3 core for interlinked smokes anyway, why run a separate 2 core everywhere too when you can just take it off the smokes in each room?) - sounds like a switched on spark who's done it.

 

[kingeri]

When I think more about it, it's probably been done to save cable (if you need to run 3 core for interlinked smokes anyway, why run a separate 2 core everywhere too when you can just take it off the smokes in each room?) - sounds like a switched on spark who's done it.

Well the circuit goes to various points on each floor for the smokes and then at the last smoke (which is on the top floor) the lighting branches off just for that top floor.

 

[Risteard]

just wanted opinions on it.

Essentially it is just a lighting circuit like any other. (It's not exactly an orthodox way of wiring it but that's about all that can be said about it.)

 

[madmaz]

To be honest I've done this many times on Rewires, I run twin to the down smokes then the 3 core interlink which eventually ends at the upstairs smoke from there a twin runs to do the upstairs lighting, smokes are powered from a regularly used lighting circuit and saves an extra cable, I like the idea that if the lighting circuit is faulty your smokes are faulty ...... (you notice you have a problem) where as the dedicated smoke circuit in fault is not as apparent unless there is a mains fail alert

 

[Midwest]

Smokes on their own circuit, do make a funny beeping noise after a while, if the circuit is isolated. But we've had this discussion before, and I can't be bothered to have it again

 

[7029 dave]

Smokes on their own circuit, do make a funny beeping noise after a while, if the circuit is isolated. But we've had this discussion before, and I can't be bothered to have it again

Go on beep beep.

 

[Midwest]

Go on beep beep.

Here you go then;
View attachment 35220

 

[7029 dave]

Here you go then;
View attachment 35220

Ha Ha , your nuts. lol

 

[DPG]

Ha Ha , your nuts. lol

I hate to be a grammar ----, but why are you laughing at his nuts?
Daz

 

[Midwest]

I hate to be a grammar ----, but why are you laughing at his nuts?
Daz

You haven't seen em!