Mains smoke alarm interconnect - wire colour?

[antsbradley]

Hi,

Just fitting mains smoke + heat detecters in residential house, which will be powered from a single lighting circuit. However I am unsure what colour wire to use for the single wire interconnect. The house has both old red/black, and the harmonsed blue/brown as it has a recent extention, and the interconnect will be running thru both areas.

I have seen it mentioned many times to use black for interconnect but that seems like a very bad idea as obviously could be confused with the neutral in the older wiring.

Can I use grey?

Thanks!

Anthony

 

[breezer]

use what colour you like there is no standard

 

[Lectrician]

Tut tut breezer - I know you want to lean from the norm, but hey!

You should be using the brown for the live and the grey sleeved blue for the neutral as per the NIC quidelines (and many other guides). This leaves the black for the interconnect, which is ELV, and therefore happy to be just black. No sleeve required.

No arguments please guys - This is the standard that is recommended and should ideally be followed. The interconnect is never mains voltage - How do you think it interconnects during a power failure?

 

[antsbradley]

Hi, I wasn't going to use 3 core cable runing between each detector, but rather pick up power from the local light fitting near each detector and run a small single wire for the interconnect signal between all 3 detectors; is that not permitted? If so what colours can the interconnect be? I really would rather not use black given that there is red and blaclk cable already used for power.

Thanks Anthony

 

[breezer]

what you do is your choice, however, you will need a single, double insulated core to intercoonect all detectors, its probably chepaer and less hassle to use a 3 core and earth.

Oh, and i have to say its a requirement for you NOT to connect each detctor to a local light under the 17th, even though to do so was a better idea.

clicky

 

[antsbradley]

looks like it will be better all round to just run new 3 core as you suggest then, fortunatley I have some spare slots in the consumer unit, its split load so I guess it would make snese to put in ont a small breaker on the non tripping side?

Thanks

Ants