Solar powered fire alarm system ???

[Benzerari]

Guys;

Normaly the power provision and service is the reponsibility of the building electrical contractor, and the fire alarm company just uses a spur from the distribution board to feed the fire alarm system, what is or what would be the position of the regulations and standard, if a fire alarm system is fed from its own photovoltaic solar power supply?

Would it be a must for the Service Company to be in charge of servicing both the fire alarm system and its own solar power supply?

As the solar power can supply the DC power signal (24-27.6Vdc) to feed the fire alarm system straight forward, without need to convert to 230 AC, and goes through the main distribution unit of the building, then dedicate one  spur switch for fire alarm system... and so on...

Is there any mentions about feeding fire alarm systems from any sort of sustainable power in BS?

Thank you

[Graeme]

no and it would be a specialist company who would be looking after solar panels.

never heard of this one before..

[David Rooney]

Excuse my ignorance regards photovoltaics, but you're implying feeding the FP straight from the cell. How does it cater for standby periods and backups etc ?

[Owen66]

But you could (in theory) at least us a PV array to charge the standby batteries. Depending on the category (and hence the standby capacity) it may be possible to engineer an oversized standby battery coupled with an ability to recharge in 24 hours even on the "worst" design day condition. As an alternative, a combined PV array coupled with a small wind turbine could charge batteries directly or charge batteries then run the output through an invertor to replicate the "mains" to the panel. BS 5839 recognises that mains supply may fail and expects a reasonable level of attention from an occupier if this outage is extended beyond the standby supply capacity

A thorough read through the commentary to Clause 25 in BS 5839 along with an understanding of the requirements for certification (an perhaps a whizz through EN 54- 4) should allow this solution to be deemed compliant (but I,m not sure I would want to be signing to that effect though )

Regards

Owen

[David Rooney]

But that does seem like a lot of agg when you could just use the 230v output from the PV array to feed your panel in the normal manner, use your standard standby batteries for worst case (72 hour) and dial out on redcare if there is a mains failure ......

[Benzerari]

Excuse my ignorance regards photovoltaics, but you're implying feeding the FP straight from the cell. How does it cater for standby periods and backups etc ?

I mean by straight forward feed, from a fully well designed stable solar power supply that can supply a stable output DC power signal, obviously it has to have a backup battery and secondary battery too if necessary, this would be without need to go through another converter to get 230 ACV, to feed the distribution board of the main building and then dedicate a spur switch for fire alarm system only.

[Benzerari]

But that does seem like a lot of agg when you could just use the 230v output from the PV array to feed your panel in the normal manner, use your standard standby batteries for worst case (72 hour) and dial out on redcare if there is a mains failure ......

Agreed, but this is not my main enquiry Dave.

[Benzerari]

no and it would be a specialist company who would be looking after solar panels.

never heard of this one before..

Thanks for this clear answer Grame

[Benzerari]

But you could (in theory) at least us a PV array to charge the standby batteries. Depending on the category (and hence the standby capacity) it may be possible to engineer an oversized standby battery coupled with an ability to recharge in 24 hours even on the "worst" design day condition. As an alternative, a combined PV array coupled with a small wind turbine could charge batteries directly or charge batteries then run the output through an invertor to replicate the "mains" to the panel. BS 5839 recognises that mains supply may fail and expects a reasonable level of attention from an occupier if this outage is extended beyond the standby supply capacity

A thorough read through the commentary to Clause 25 in BS 5839 along with an understanding of the requirements for certification (an perhaps a whizz through EN 54- 4) should allow this solution to be deemed compliant (but I,m not sure I would want to be signing to that effect though )

Regards

Owen

Owen, thanks for this info. feeding fire alarm system from the mains power supply of the building what ever the source of power provision, is still within the standard as you mentioned.

But feeding straight forward a fire alarm system from its own well designed solar power supply is still my main issue. so what ever happened to the power of the building that would not take effect on the solar power of the fire alarm system. is or would that be acceptable by BS?

[Owen66]

But that does seem like a lot of agg when you could just use the 230v output from the PV array to feed your panel in the normal manner, use your standard standby batteries for worst case (72 hour) and dial out on redcare if there is a mains failure ......

I agree it may be a lot of aggro but I think the OP was looking to omit the invertor (along with all the attendant inefficiency involved) and using a DC output to charge batteries for standby (much as we do when mains is available).

Clearly the PV array would need to deal with the worst predicted case based on geographic location/orientation and possibly a bit of electrical engineering to find a means of "rejecting" over capacity if the batteries are fully topped up.

It would also be debateable if the energy saved by the PV would even offset the embodied carbon in its construction or the capital cost could ever be recovered in the system lifecycle

I'm not saying it is conventional just that it may well be achievable when refernced to BS 5839 and EN 54.

Regards

Owen

[Owen66]

But you could (in theory) at least us a PV array to charge the standby batteries. Depending on the category (and hence the standby capacity) it may be possible to engineer an oversized standby battery coupled with an ability to recharge in 24 hours even on the "worst" design day condition. As an alternative, a combined PV array coupled with a small wind turbine could charge batteries directly or charge batteries then run the output through an invertor to replicate the "mains" to the panel. BS 5839 recognises that mains supply may fail and expects a reasonable level of attention from an occupier if this outage is extended beyond the standby supply capacity

A thorough read through the commentary to Clause 25 in BS 5839 along with an understanding of the requirements for certification (an perhaps a whizz through EN 54- 4) should allow this solution to be deemed compliant (but I,m not sure I would want to be signing to that effect though )

Regards

Owen

Owen, thanks for this info. feeding fire alarm system from the mains power supply of the building what ever the source of power provision, is still within the standard as you mentioned.

But feeding straight forward a fire alarm system from its own well designed solar power supply is still my main issue. so what ever happened to the power of the building that would not take effect on the solar power of the fire alarm system. is or would that be acceptable by BS?

Well it may be acceptable but really that is a decision for the system designer to agree with his client and other relevant parties - I can't tell you categorically it will comply or won't comply

Regards

Owen

[Graeme]

But you could (in theory) at least us a PV array to charge the standby batteries. Depending on the category (and hence the standby capacity) it may be possible to engineer an oversized standby battery coupled with an ability to recharge in 24 hours even on the "worst" design day condition. As an alternative, a combined PV array coupled with a small wind turbine could charge batteries directly or charge batteries then run the output through an invertor to replicate the "mains" to the panel. BS 5839 recognises that mains supply may fail and expects a reasonable level of attention from an occupier if this outage is extended beyond the standby supply capacity

A thorough read through the commentary to Clause 25 in BS 5839 along with an understanding of the requirements for certification (an perhaps a whizz through EN 54- 4) should allow this solution to be deemed compliant (but I,m not sure I would want to be signing to that effect though )

Regards

Owen

thats giving me a headache lol.

can't see the point of it personally from a  green or money saving point of view considering how little a fire system draws.

[Owen66]

But is it actually that small - bearing in mind there can be a lot of current consuming peripherals on a fire alarm system and these are present 24/7/365 for say 25 years.

As I said, it may not actually pay for itself or even offset the carbon used to manufacture the PV - but perhaps a small wind turbine could potentially reach break even point without undue technical risk.

Regards

Owen

[David Rooney]

Well if sticking financially non viable PV cell and wind turbine on my roof will help save the planet inspite of the extra 250,000 odd planes expected when terminal 6 gets the go ahead, (assisted by half the old labour party sitting on the board of BAA), and the new coal powerstations going up in china every week then its a small price to pay....

(sorry not really the answer to the question just fancied a rant at the PC, green fingered, tree hugging, bio degradeable, ozone friendly brigade.....)

[Benzerari]

Well if sticking financially non viable PV cell and wind turbine on my roof will help save the planet inspite of the extra 250,000 odd planes expected when terminal 6 gets the go ahead, (assisted by half the old labour party sitting on the board of BAA), and the new coal powerstations going up in china every week then its a small price to pay....

(sorry not really the answer to the question just fancied a rant at the PC, green fingered, tree hugging, bio degradeable, ozone friendly brigade.....)

Obviously No, but if every one and every sector does his bit why not. We may save the planet. Also there is still always some ways to do better