Mains smoke alarms

[Andygasman2010]

Alright guys, just after a bit of advice on the above.

I'm doing some building work at home at the moment and at some point in a few months or so I'll be getting an electrician to fit interconnected mains smoke alarms.

I'm assuming one will be fed from the consumer unit and all connected together in series?? Correct me if I'm wrong, of course!

The stage I'm at right now is that shortly, the only route from the consumer unit to upstairs will be boxed in and plastered so I'd like to run some cable up it in preparation for the sparky later on (I won't be connecting anything up)

What cable should I use?

Cheers!
Andy

 

[OwainDIYer]

they will be wired in parallel, and most use triple-and-earth cable between the detectors.

 

[Bill Stickers]

You need to run a 1.5mm² twin and earth from the C.U. to the first smoke alarm and then 1.5mm² three core and earth from the first alarm in a daisy chain to each subsequent alarm.

Make sure all cables are run with in safe zones if they are to be concealed within the fabric of the building. More info is in the wiki.

 

[seasickstevie]

An option is to fit a test button at the mains. I'm not sure exactly how it's connected, but I'd be inclined to do the first leg in three-core- &-earth also, that way you've got your signal back to a convenient point. You could always use that to trigger a dialer to give a remote signal if you wanted.

 

[flyingsparks]

The main feed can be twin and earth or 3 core 6243y but the interlinking cables should be fp200 fire resistant cable.

 

[Taylortwocities]

but the interlinking cables should be fp200 fire resistant cable.

This is not necessary in a domestic smoke alarm system. FP cables would be needed in a FIRE alarm system but that is not what the OP is proposing to install.

Also the power feed for the smoke alarm system can come from a regulary used lighting circuit.
This is a good choice for a domestic system as there will be an obvious indication if the fuse/CB were to trip.

 

[Andygasman2010]

Cheers guys. I might as well give it it's own supply from the consumer unit seeing as I'm able to at this point.

I've got plenty of spare 2.5mm twin and earth so I'll send 2-3 feeds through the boxing just in case, no worries if they don't get used.

Thanks again!

 

[phatboy]

Cheers guys. I might as well give it it's own supply from the consumer unit seeing as I'm able to at this point.

I've got plenty of spare 2.5mm twin and earth so I'll send 2-3 feeds through the boxing just in case, no worries if they don't get used.

Thanks again!

Using 1mm T&E will be far easier to fit in a smoke alarm.

As recommended, it would be best to connect it to a lighting circuit, that way if the breaker was to trip, you would know about it.

 

[ban-all-sheds]