Smoke detector help please

[mungo9]

I have recently completed my first job and it was an extension to my Uncles house. i haven't qualified yet but the job went well and everything works, although i have 1 issue. Due to my lack of experience where my uncle was trying to save money on the job he said he didn't want smoke detectors wired in and would buy them separately, obviously i normally wouldn't say thats okay. However now the job has ended and the Building inspector is coming round soon, i realise to be safe and make sure everything passed i should have just put them in. I still need to choose the battery powered smoke and heat detectors that will pass.
Can anyone tell me what battery powered smoke dectectors i should get? and if they comply with the regs.

 

[tazz]

And me, its there in black and white, and confirmed by Aico.....isolation not required...end of totally

 

[Richard Burns]

I totally agree with Tazz.

 

[telectrix]

me also.. but i'm hoping he'll chuck some more work my way .LOL> :shades_smile:

 

[gutterball]

i'm siding with tazz as well, it's a HOUSE it won't matter if the power to the lights are off for maintenance.

 

[Simlec]

But its a building reg! not a recommendation like the BS books.

Take your mains smoke alarm from the lighting circuit.
Read the instructions for the smoke alarm (Aico will do) and it clearly states "Disconnect main before removal" referring to the unit.
The building reg states.....There should be a means of isolating power to the smoke alarms without isolating the lighting.
So how do you isolate the supply to the smoke alarms without turning the lights off?

Its not rocket science is it...
First he says there not smoke alarms now he says they are but forget the building regs...

 

[tazz]

Have asked a few bsi trainers, Aico and kiddie for their views, All manufactures smoke alarms meets required EN standard to allow their detectors to be installed to BS and Document B without the need for separate isolation....this is achieved by using a anti tamper base, which can only be removed by using a tool, such as a screwdriver. Bases have been manufactured to allow safe disconnect, without exposing live conductors. And thus comply.

 

[Slowhand]

Just a thought but what about isolation if the cable gets damaged?

 

[tazz]

Comes under the rule shown in post standard of share protection...ie lighting circuit

 

[cprfenom]

Please show the whole of the section instead.of trying to mislead members... as you can see from notes 1 and 2 the mcb suppyling the circuit, and the base of the detector itself forms the isolation for maintenance...!!! Have contacted Aico to confirm, no isolation is required, as wired base conforms to methods required for maintenance, and isolation.

15 Power supplies
15.5 Recommendations for power supplies for Grade D
Systems
a) ii) a separately electrically protected, regularly used local
lighting circuit in which case there should be a means for
isolation of the smoke alarm(s) from the lighting circuit (e.g. for
maintenance).
NOTE 1 This does not imply that there need be separate
Electrical protection of the smoke alarm circuit; a single means
of protection against overload or short circuit (e.g. a fuse or
miniature circuit breaker) serving the entire circuit is
acceptable.
NOTE 2 A number of manufacturers use a fixed base for the
electrical connections, and the smoke or heat alarm can be
readily removed by use of a tool operated release tab, etc.

I'm sure I read that they couldn't be on an RCCB that protected a socket circuit?

 

[tazz]

Whats has a socket circuit, got to do with this thread...??

 

[Slowhand]

Comes under the rule shown in post standard of share protection...ie lighting circuit

I was taught that one circuit shouldn't affect another circuit and shutting a lighting circuit down to maintain a smoke alarm circuit or vice verca contradicts that.
A separate circuit makes more sense.

 

[tazz]

You dont need to turn off power to replace or maintain the detector, that is the point of an isolation base. The whole point here is to stop unauthorised people disconnecting the detection.

 

[Risteard]

I was taught that one circuit shouldn't affect another circuit

It wouldn't if the smoke alarms are on the lighting circuit. No circuit other than the lighting circuit would be affected.

And as said there's no reason particularly why it need affect the lights on the lighting circuit (depending on the exact nature of the work being carried out).

 

[cprfenom]

Whats has a socket circuit, got to do with this thread...??

I thought I had read that they had to be on a dedicated circuit and one that in the event of tripping didnt knock out sockets.

That's what I meant by I thought they couldn't be on an RCCB that covered sockets.

BS5839-6 states that :-
i) The r.c.d. should serve only the circuit supplying the smoke alarm(s) and heat alarms OR
ii) The r.c.d. protection of a smoke alarm circuit should operate independently of any r.c.d. protection for circuits supplying socket outlets or portable equipment.

Or am I reading this all completely wrong

 

[shanky887614]

I thought I had read that they had to be on a dedicated circuit and one that in the event of tripping didnt knock out sockets.

That's what I meant by I thought they couldn't be on an RCCB that covered sockets.

BS5839-6 states that :-
i) The r.c.d. should serve only the circuit supplying the smoke alarm(s) and heat alarms OR
ii) The r.c.d. protection of a smoke alarm circuit should operate independently of any r.c.d. protection for circuits supplying socket outlets or portable equipment.

Or am I reading this all completely wrong

a lighting circuit isnt a portable appliance you halfwit