SWA feeding fire panel

[kenny maccuish]

Hi guys I have just done an Eicr and 1of my findings was that the fire alarm panel was fed by SWA and I am wondering if that needs replaced with fp200 or similar?
Thanks in advance
Kenny

 

[James]

Not normally required, battery backup on fire alarm should deal with Loss of supply due to fire for long enough to do its job.

 

[littlespark]

Normally fire alarm panels are fed in regular t&e from wherever… to a standard fused outlet. Normal flex from there into the panel.
fp200 coming out to the zones though

 

[Lister1987]

5839-1 is explicit in that ALL parts of the system should be in a fire resistant cabling, including the feed from DB to FCU on that alarm panel itself. FP400 to replace the SWA. I'll hook out relevant parts when I get a sec

 

[timhoward]

I agree with @Lister1987 in as much as if it were installed today the supply should be a dedicated circuit in fire resistant cabling. (Section 25 of BS5389)
But plenty of things were allowed on fire alarms back in the day including this, and 4 core for detectors and sounders, and detector circuits/call points were even allowed to be regular T+E once. I believe 2002 was the significant year for the regs tightening up.

The thing is, I don't think this is codable on an EICR as anything other than a note.
After all, it isn't electrically unsafe and in any case as I understand things BS5389 isn't retrospective either.
Is there any justification within BS7671 for coding it?

 

[Lister1987]

You could use 560.10 but as you say, it complied at time of install, was it ever modified after install? Just got visions of the system being done to 2 versions of 5839.
I'd compile a list of required actions to bring it to current code, advise it was likely to code when installed, discharge the duty of care and leave it to the client to decide what to do.

 

[telectrix]

the fact that the fire alarm is fed in SWA is irrelevant to your EICR as long as the SWA complies with BS7671. i.e it'ssuitable for the load; it is installed in accordance with BS7671 (glanded properly etc.). Your EICR has no relationship to BS5839.

 

[westward10]

You need to specify the type of swa as it may be compliant.

 

[pc1966]

You need to specify the type of swa as it may be compliant.

Do you mean from a LSZH point of view or a high temp survival point of view?

Edit: Just searched and indeed there is fire resistant SWA around:

BS 7846 SWA Armoured Fire Resistant Power LSHF Cable

www.fscables.com

Learn something new every day!

 

[westward10]

the fact that the fire alarm is fed in SWA is irrelevant to your EICR as long as the SWA complies with BS7671. i.e it'ssuitable for the load; it is installed in accordance with BS7671 (glanded properly etc.). Your EICR has no relationship to BS5839.

BS7671 makes reference to supplies for safety systems hence it is relevant.

 

[kenny maccuish]

You need to specify the type of swa as it may be compliant.

Pretty sure it's just standard SWA but I would need to double check

 

[timhoward]

Back-tracking, having read 560.8.1 in BBB I do now think it's a fair shout to code a non compliant fire alarm supply.
It's worth a look at that reg, indent iv), and note 2, as if enclosed appropriately or if the wiring is run in a different fire compartment it looks like it may comply even if not fire rated cable.

 

[Lister1987]

Forgive me chaps but it does boil my ---- when people say that 5839 has no relevance to 7671 (and vice versa). The whole point of Chapter 56 to to draw attention to the fact 7671 applies at a fundamental level to a variety of other (safety) standards, once just read the scope of 7671 and appendix (I want to say) 2.

We can all be guilty of tunnel vision at times (I'm here for electrical inspection only and forget that there are places in 7671 that overlap in another standards. "Oh it's a fire alarm, I don't touch fire alarms"....yes but how is your fire alarm powered? "Mains from that DB and battery backup..lightbulb moment ohhhh, now I get it, if thr supply doesn't have the same protection as the fire alarm devices then it will of course fail before the equipment has chance to do its job (battery backup aside - given we can't ensure the batteries are correct as we're not working to 5839)

Everyday is a school day and discussion drives improvement

 

[telectrix]

BS7671 makes reference to supplies for safety systems hence it is relevant.

i worded that badly. what i meant was that your EICR does not relate to whether or not it complies with BS5839, as long as it complies with BS7671. although a comment could be made to make customer aware.

 

[kenny maccuish]

Excellent guys thanks for the input and help.

 

[Fender]

I may get shot down for this, but what the hell...

I haven't fitted a fire alarm for years. But the way it was done was to make the supply for it originate from a switch/fuse solely for the fire alarm. In other words completely independent from the main DB. The old favourite adiabatic came in handy to be able to do this so smaller tails could be used.

If this 5839 regulation still stands, then virtually all Grade A systems are wrong and apparently should be highlighted in an EICR.

If this requirement has changed then not only have I wasted 10 minutes of my time writing this, but also 1 minute of your time for reading it.

 

[westward10]

I think the original reason for this was when fire alarm systems were mains operated systems with no secondary back-up like we have now and this practice just stuck. It is a requirement now that it should be supplied from a dedicated circuit.

 

[Fender]

I think the original reason for this was when fire alarm systems were mains operated systems with no secondary back-up like we have now and this practice just stuck. It is a requirement now that it should be supplied from a dedicated circuit.

Jesus! How old do you think I am?

I think battery back up has been required for 40/50 years. I've never installed a system without. We had little red painted switch fuses made just for this purpose.

I did come across a system wired in MICC, single core for the call points. The MICC sheath was used as the fire alarm 'trigger'.

Was from the 1940's, battery backed. And no, I didn't install it...

 

[westward10]

Jesus! How old do you think I am?

I think battery back up has been required for 40/50 years. I've never installed a system without. We had little red painted switch fuses made just for this purpose.

I did come across a system wired in MICC, single core for the call points. The MICC sheath was used as the fire alarm 'trigger'.

Was from the 1940's, battery backed. And no, I didn't install it...

As I said the practice from years back just stuck.

 

[Fender]

As I said the practice from years back just stuck.

But has BS 5839 been changed so that the independent switch fuse is no longer needed. I admit that I have taken the supply from loads of DB's, knowing that it was wrong, and ignoring the standards.

But so was everybody else. If it has changed, is it because it was totally ignored? Or has it not been changed? I don't know anything anymore.

I'm going to check the wiring out at The Cricketers so I don't get more confused.