Smoke detectors

[Innominata]

Hi Guys,
I have just completed a PIR for a house that has had a recent upgrade.The general condition is very good.The only thing that I am not sure about is the fact that the hall smoke detector is supplied from the nearby hall light,and the landing smoke detector is supplied from the landing light.The two alarms do not appear to be interconnected.Is this arrangement ok or should it be given a PIR code.
Many thanks

 

[Brian Boyd]

I`d make note of it on pir and cover yourself as best you can.

 

[RexT]

Hi,

I am sure that the smoke alarms should be interconnected and battery back up(?). I agree that this should be recorded on the PIR as you have discovered it.

Are they going to rectify the connection?

Best wishes

Rex

 

[BVES]

You did check they were ot linked by radio link?

 

[Spudnik]

That what i was thinking.

If they are, it takes a few seconds from when the test button is pressed on one, for the other(S) to sound.

 

[Sav]

Hi,
I had a similar problem, I gave it a code 4 (recommendation) and also gave the customer a quote to fit the radiolink bases to the detectors. They are about £35.00 each radiolink. The smoke detectors were from B & Q, so did not have the capability of being radiolinked.
In the end I used the Aico smoke alarm units (optical multisensors, with battery backup and can be radiolinked).
Quick and easy and the customer was pleased.

Best regards,
Sav

 

[RexT]

Hi Innominata,

I must admit the radio link option sounds good and quite reasonable priced. When you did the PIR did you notice if there was three core and earth run between the smoke alarms? I f so I guess it might have been cheaper to replace the fitted smoke alarms if the cabling checked out ok.

Interesting stuff and this forum is great for some sound advice.

Hope this helps.

Best wishes

Rex

 

[Innominata]

Thanks Guys I will check the radio link

 

[1billy wiz]

can someone be kind enough to explain radio link pls.

to my understanding a fire alarm can be off a lighting circuit if it can be isolated by a spur right??& it cant be on a 30ma circuit neither right??

does radio link mean you only need to supply power to one alarm???

sorry people but fire alarms & extractor spurs in bathrooms stump me!!

 

[mnmwill]

A radio link gives a wireless link between the smoke alarms, saves trying to route 3 core from one to the other.

 

[JUD]

can someone be kind enough to explain radio link pls.

to my understanding a fire alarm can be off a lighting circuit if it can be isolated by a spur right??& it cant be on a 30ma circuit neither right??

does radio link mean you only need to supply power to one alarm???

sorry people but fire alarms & extractor spurs in bathrooms stump me!!

In bold:

This isn't entirely true.

Where the use of an RCD can't be avoided it is arguably preferable for the supply for the fire alarm system to be taken from a regularly used lighting circuit as operation of the RCD/RCBO will soon be known (for other than Grade D systems, BS 5839-6 recommends avoiding the use of RCDs on fire system circuits. This will usually require clipping cables direct to the surface or enclosing in steel conduit or the like).

This is from the IEE Electricians Guide to Fire Detection and Alarm Systems

 

[All Sorts]

I gave it a code 4

slight interjection if I may.. is there an online doc available anywhere that lists all possible codes and their descriptions?

Thanks in anticipation

 

[Sav]

Hi Allsorts,
If you go onto the Electrical Safety Council website Electrical Safety Council (ESC) | Committed to reducing deaths and injuries of electrical accidents at home and at work , you can download the Periodic Inspection Reporting document which has all the codes in there.

Alternatively, try the Elecsa website as well.
Hope this helps,

Sav

 

[1billy wiz]

In bold:

This isn't entirely true.

Where the use of an RCD can't be avoided it is arguably preferable for the supply for the fire alarm system to be taken from a regularly used lighting circuit as operation of the RCD/RCBO will soon be known (for other than Grade D systems, BS 5839-6 recommends avoiding the use of RCDs on fire system circuits. This will usually require clipping cables direct to the surface or enclosing in steel conduit or the like).

This is from the IEE Electricians Guide to Fire Detection and Alarm Systems

so if the lighting circuit is on a rcbo becuse the bathroom lights need protecting by 30ma i need to either do a spur of the sockets for the bath lights & change over cb for the lights or run a radial right?

 

[JUD]

so if the lighting circuit is on a rcbo becuse the bathroom lights need protecting by 30ma i need to either do a spur of the sockets for the bath lights & change over cb for the lights or run a radial right?

I don't think you've understood it correctly.

Basically what it is saying is that if you must use an RCD then it is better to run the smoke alarms off a regularly used RCD protected lighting circuit because if the RCD trips you will know about it straight away as none of the lights on that circuit will work.

NOTE: This only applies to Grade D systems which are installed in dwellings.