A colleague of mine says he read in bs7671 that equipment in lofts may need an Arc Fault Detection Device.
I can't find such a requirement, perhaps someone here has heard of it?
A colleague of mine says he read in bs7671 that equipment in lofts may need an Arc Fault Detection Device.
I can't find such a requirement, perhaps someone here has heard of it?
A colleague of mine says he read in bs7671 that equipment in lofts may need an Arc Fault Detection Device.
No such requirement in BS 7671 to my knowledge, and to my knowledge no requirements, guidance or notes that specifically mention 'loft' in the standard.
However, there is a recommendation in BS 5839-6, for an interlinked detector to be provided for the fire detection and fire alarm system, when electronic equipment (like inverters, batteries) are installed in lofts.
I would also point out:
There are recommendations in RiskAuthority RC62 to check whether you should fit an "arc fault circuit interruptor" (which is another term for AFDD), but that doesn't mention a loft.
Also, are you talking about AC or DC side (some inverters have DC side arc fault detection but that's different to AFDDs) ?
If there is more 'pollution' (dust) than expected, this might result in fire.
Might it not also lead to false alarms? If so, perhaps a heat detector is more appropriate than a smoke one.
Might it not also lead to false alarms? If so, perhaps a heat detector is more appropriate than a smoke one.
Agreed, include the detector in the list of "equipment" with respect to pollution, although yes a smoke detector is more susceptible.
Often discussed where batteries are concerned, because some form of smoke/vapour detector is needed (when the fire happens with lithium, it's too late, so a heat detector isn't really very good for getting people out quickly) ... and of course in many lofts these don't work work well.
More work certainly needed on detection and alarm for batteries really.
More work certainly needed on detection and alarm for batteries really.
How about putting a battery in a steel cabinet? It occurred to me that some form of fire safe (eBay is your friend) might do if the joists would cope. A detector in there would not be subject to external influences, and if the cabinet can protect documents for 30 (or 60 or WHY) minutes, it should work the other way about.
I'm not sure putting the battery in a steel cabinet completely solves the problem - it could still catch fire and need extinguishing, unless it's known that it could be contained by the steel cabinet until it's fully combusted and has self-extinguished, any smoke released could be trapped into the loft making entry into the loft very hazardous as it's something of a confined space.
Plus there's the cooling aspect, ambient temperatures in lofts can be very high in summer, a sealed cabinet would impact cooling.
I see some manufacturers are now selling batteries with built-in fire suppression systems, using suppression fluid to prevent a fire in event of a cell thermal run-away. But again, in a loft that vapor/smoke release would all be going into the loft space.
Personally, I think we ought to approach the problem from another perspective, that lofts are inherently not and will quite likely never be a good location for energy storage devices due to a combination of extreme ambient temperatures, confined spaces, poor ventilation, presence of combustible building materials, infrequent access/inspection, risk of fire spread to bedrooms. So therefore what is required are better and more workable arrangements to get DC around a property so that the battery and/or inverter can be located somewhere more appropriate.
How about putting a battery in a steel cabinet?
Perhaps worth looking at the result of some battery fires ... particularly Lithium.
it could still catch fire and need extinguishing
Which is a problem, when the battery makes its own fuel and oxygen in thermal runaway.
Yes, it can work (with appropriate ventilation to outdoors), BUT something to keep it cool for up to 20+ hours whilst it burns itself out is definitely needed.
Personally, I think we ought to approach the problem from another perspective, that lofts are inherently not and will quite likely never be a good location for energy storage devices due to a combination of extreme ambient temperatures, confined spaces, poor ventilation, presence of combustible building materials, infrequent access/inspection, risk of fire spread to bedrooms. So therefore what is required are better and more workable arrangements to get DC around a property so that the battery and/or inverter can be located somewhere more appropriate.
Agreed ... but see below regards DC.
In domestic situations, outdoors, where it can be cooled, seems to be best overall. PAS 63100 provides this guidance (applicable for all battery chemistries for usable storage capability).
In terms of DC, this is perhaps more problematic. Standards for DC protection etc., are lagging a little behind AC counterparts. We've not used DC in homes on a great scale since the last DC supplies were removed from domestic properties in the 1960s (I don't think, at least in general, many if any survived into the 1970s, but happy to hear if anyone has other information).
The big problem with DC, is arc flash, and arcs being drawn on disconnection, meaning fire protection of the wiring system etc. is more difficult. We also have fewer people with skills and experience in the field at the moment. Needs a lot more discussion ... An example is fuse-carriers for battery storage systems in homes, that ought to be limited access to skilled and instructed persons, being simply installed on the wall (of say the garage, or another location) in domestic premises with no other protection or enclosure.
In domestic situations, outdoors, where it can be cooled, seems to be best overall. PAS 63100 provides this guidance (applicable for all battery chemistries for usable storage capability).
Graham, thank you. I have now read the PAS, which was helpful and I see that lofts are precluded (6.5.5(g) ).
However, presumably one could install a battery in a (small) room which has been created out of part of a loft. I am not sure whether that would make a material difference in the event of a fire.
How close to the inverter should batteries be installed please?
However, presumably one could install a battery in a (small) room which has been created out of part of a loft. I am not sure whether that would make a material difference in the event of a fire.
I guess it would depend whether the "room" conformed to the Building Regulations for rooms of buildings? But I agree, overall, what's to gain?
How close to the inverter should batteries be installed please?
As close as practicable, to reduce round-trip losses through volt drop.
However, presumably one could install a battery in a (small) room which has been created out of part of a loft. I am not sure whether that would make a material difference in the event of a fire.
I guess it would depend whether the "room" conformed to the Building Regulations for rooms of buildings? But I agree, overall, what's to gain?
How close to the inverter should batteries be installed please?
As close as practicable, to reduce round-trip losses through volt drop.
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