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.

 

[Simlec]

No because they have an integrated one.. and are called smoke alarms.
They are a self contained power supply, backup supply, detection and sounder all in one.

Is that not a system

 

[tazz]

Ok look at it this way, where on your grade D mains operated smoke detection system, do you connect to a fire alarm mains power supply, which inturn is connected via and isolator to the dwellings db...?

 

[Simlec]

I must be reading the spec wrong

 

[tazz]

I think you are

 

[Simlec]

View attachment 25577
Humm... so if its not a smoke alarm.. what is it?

 

[shanky887614]

View attachment 25577
Humm... so if its not a smoke alarm.. what is it?

standard smoke detector.

it states it is mains powered so it will need to go back to a fire alarm panel in certain cases.

 

[tazz]

As you said a smoke alarm....not a smoke system.
you can bend and alter the regs, as much as you wish.....but document B, under your own post, states clearly POWER SUPPLIES, then in 1.19 states isolation of power supply(s) connected to a smoke system. later it concludes smoke detection (NOT POWER SUPPLIES) with backup batteries, can be connected direct to lighting circuits....I totally rest my case.

 

[Simlec]

Grade A,B & C are what Tazz is referring to as they have a panel with a power supply.
But as Grades A, B & C require a dedicated supply (Yes C can have a intruder alarm with it)
you would not be coming from a lighting circuit would you now unlike a Grade D which can.
So why put a comment about isolation with lighting circuit in the document...

 

[tazz]

Again it under power supplies it has no mention of lighting circuit, it states clearly connected to dwellings db via isolation. ie grade A or part 1 system panel

 

[Octopus]

This thread just goes to demonstrate why heres confusion about this subject!

Time for the plain English Society??

 

[Simlec]

No because they have an integrated one.. and are called smoke alarms.
They are a self contained power supply, backup supply, detection and sounder all in one.

The Approved Document then goes on to describe/give example of other types of power supply, your Grade A supply 1.22

BS 5839-1 page 76 "25.2 Recommendations for mains power supplies"
What part should I be looking at ?? as its just standard stuff.

I will also have a look at BS 5839-6 as this is for dwellings same as Approved Document Volume 1

 

[gutterball]

what we need to look at is the type of building and it's use. are you going to put a alarm panel in an ordinary 1 or 2 story family home?

 

[Simlec]

Sorry Tazz it also states this in BS 5839 -6 page 42

 

[tazz]

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.

 

[Simlec]

God give me strength. It's like pulling teeth..
How can you use the MCB if it connected to the lighting circuit?
not all smoke manufactures use a plug type arrangement for the base.