smoke alarms with battery back up

[thomo27]

Evening all...just after your choices on smoke alarms in dwellings..do you put them on there own circuit rcd protected on a split load board? Or on a seperate RCBO...

 

[andreaccc]

well the only ones i know are the ones that just stick there - they are in no way connected to an electric supply as they ahve their own battery

i had some done by a fireman a while ago , and they do them for free , but dont quote me on that ,if you dont have them they were very good

 

[jamesmcbride]

1.17 The power supply for a smoke alarm system should be derived from the dwelling’s mains electricity supply................If alarm comprises no stand by power supply, [ie AC ONLY] no other electrical equipment should be connected to this circuit. [ie AC only alarms, must only be wired back to main consumer unit on dedicated circuit].

1.18 A smoke alarm, or smoke alarm system, that includes a standby power supply or supplies, [ie AC with battery back up], can operate during mains failure. It can therefore be connected to a regularly-used local lighting circuit. ...............

1.19 Devices for monitoring ...............

...............If a continuous audible warning is given, it should be possible to silence it.

1.20 The smoke alarm circuit should preferably not be protected by any residual current device (rcd). However if ...............

1.21 Any cable suitable for domestic wiring may be used for the power supply and interconnection to smoke alarm systems. It does not need any particular fire survival properties.


I have mine on a separate RCBO regardless

 

[Taylortwocities]

In domestic environments, it is best to power smoke alarms from a regularly used lighting circuit.

The problem with a stand-alone MCB/RCBO is that you won't get to know that the supply has failed, unless its your habit to go squinting at the power light inside the alarm on an hourly basis!

 

[Taylortwocities]

well the only ones i know are the ones that just stick there - they are in no way connected to an electric supply as they ahve their own battery

i had some done by a fireman a while ago , and they do them for free , but dont quote me on that ,if you dont have them they were very good

That's a different thing. We are talking about proper smoke alarms that can be interlinked, are mains powered and have a battery back up.

 

[PrenticeBoyofDerry]

Evening all...just after your choices on smoke alarms in dwellings..do you put them on there own circuit rcd protected on a split load board? Or on a seperate RCBO...

I do as Taylortwocities does, put on a regularly used lighting circuit.
Also your choice of smoke alarm, would be dictated by the location they are situated in.
A standard 3-4 storey house:
Hallway, landing & living room=optical or multi-sensor
Kitchen, garage=Heat
Bedrooms= Ionisation or multi-sensor

 

[Click4]

maybe im just using expensive alarms, but all this talk about owners not knowing if power fails to their alarms I cant understand as the ones ive always fitted... when the backup battery starts to go flat they produce an annoying bleeping sound intermittently until power is restored to recharge them, and theres no way you would miss that.

 

[securespark]

you won't get to know that the supply has failed, unless its your habit to go squinting at the power light inside the alarm on an hourly basis!

Or have a quick poke in the cupboard every day.

 

[jamesmcbride]

maybe im just using expensive alarms, but all this talk about owners not knowing if power fails to their alarms I cant understand as the ones ive always fitted... when the backup battery starts to go flat they produce an annoying bleeping sound intermittently until power is restored to recharge them, and theres no way you would miss that.

Likewise, so do mine. Added to the fact that if the power fails and it's on a dedicated circuit, there can only be a fault with the smoke alarm (or associated wiring)

 

[jabuzzard]

In domestic environments, it is best to power smoke alarms from a regularly used lighting circuit.

The problem with a stand-alone MCB/RCBO is that you won't get to know that the supply has failed, unless its your habit to go squinting at the power light inside the alarm on an hourly basis!

The problem with that is mine say that they are not to be connected to a lighting circuit with a fluorescent fitting. As everyone is being pushed to use CFL's that basically rules out the lighting circuit.

I went for a separate circuit shared with the front door bell so I at least stand a chance of noticing the power is off, though I believe the battery backup will start sounding before it goes totally flat. However I have never had the power off long enough to test that.

I use the EL Series 160 as it had a range of sensors and optional remote locate/test switch. That last one is handy, no climbing up chairs to silence alarms when you burn something in the kitchen. I have ionization in the lounge, optical in the hallways upstairs and downstairs and heat in the kitchen. I believe that they recommend an alarm in the principle bedroom these days as well. Though in my house the upstairs sensor is just outside the principle bedroom and there is no way you could sleep through it unless you where registered deaf.