Interconnecting fire alarms

[alchemist]

Sorry if this has been asked before, but I didn't find anything.

Can fire alarms be interconnected (for triggering purposes) if each alarm is powered from a different circuit, e.g. one on upstairs lights and one on downstairs lights. Or is it necessary that the alarm interconnection provides power from one to the next on the same circuit.

It's been a wile since I've done interconnected alarms. Do we use 3+E to interconnect, with the 3rd core being for triggering?

Thanks

Mike

Cheers.

 

[Andy™]

you normally wire them in 3C&E so will all be on one circuit

if you want them on different circuit, get wireless ones (i.e Aico)

 

[binky]

Most fire panels have some form of output/input trigger relays which are usually 12 or 24v. Just need to suss which relay does what and run cables between.

 

[matt.leung]

i am just installing some at the moment of a house re-wire. i am using 3 core + earth, interconnecting them. I have linked them all together and getting the power

from one end only, so when one does off the other two trigger.

 

[steptoe]

I think we are talking smoke detectors here , are we not, rather than fire alarms.

come on people, we really need to see things being named properly,

I know a lot of the time it makes little or no difference,

but in this case I think it could be quite important.

 

[Manator]

You are correct, a fire alarm can be interconnected to buildings that share a common ground, and is very different to smoke detectors being linked by a common cable.