Amd2 SPD on smoke alarms

[pc1966]

The type 1 SPD at source really only applies to LPS-equipped systems or ones with long overhead feed cables. Having a type 2 device is fine, so long as it is rated for the matching OCPD (if that is DNO fuse or separate MCB)

I suspect the NIC inspector is just following the "no mixed manufacture" aspect to the letter, which is kind of irrelevant for the outside DIN enclosure. But more importantly if the company making them certifies they are suitable for any CU subject to the matching MCB brand being used then they are taking responsibility for the overall design and you don't have to.

 

[pc1966]

At the CEF 18th AM2 talk when mentioning SPD the guy said smoke alarms are not "safety systems" but as usual with no detail or justification for that point.

While there may be situations with a full CU where an overall SPD is not practical to fit for new alarms, in those cases you could just get the 10 year battery / wireless ones instead. If replacing existing alarm modules then you could argue it is not a new circuit so updated regs don't apply.

If it were a new hard-wired alarm I personally don't see how you could honestly say it is not for safety and so protection is optional.

 

[UNG]

At the CEF 18th AM2 talk when mentioning SPD the guy said smoke alarms are not "safety systems" but as usual with no detail or justification for that point.

Given that smoke alarms come under BS5839 part 6 why would they not be a "safety system" I think the guy really needs to clarify his comment as they are also a requirement of the building regs

 

[Pretty Mouth]

No SPD, no smoke alarms huh? Crazy.

 

[nicebutdim]

I don't know, I wasn't there. The gaffer was the one who went around with the inspector. He couldn't see what the issue was, it's a Din module in an empty Din enclosure. Seems fine to me also, I've provided MCB protection, the correct size earth conductor and kept the cables as short as practicable.

If an inspector raises an issue, but can't give a reason for doing so (along with supporting evidence), I'd be inclined to think they were in the wrong job.

 

[freddo]

If an inspector raises an issue, but can't give a reason for doing so (along with supporting evidence), I'd be inclined to think they were in the wrong job.

A previous inspection I was picked up for not putting brown sleeving on the black interconnect wire on smoke alarms, even though all the NICEIC guides tell you to leave it unsleeved as it is an ELV control signal wire not mains switched live!

 

[Lister1987]

At the CEF 18th AM2 talk when mentioning SPD the guy said smoke alarms are not "safety systems" but as usual with no detail or justification for that point.

While there may be situations with a full CU where an overall SPD is not practical to fit for new alarms, in those cases you could just get the 10 year battery / wireless ones instead. If replacing existing alarm modules then you could argue it is not a new circuit so updated regs don't apply.

If it were a new hard-wired alarm I personally don't see how you could honestly say it is not for safety and so protection is optional.

I would advise they actually read BS7671; verbatim from 18th Amd2

 

[timhoward]

As for old boards you'll probably find the Wylex REC2SPD (main switch and SPD in a self contained unit) used to afford type 2 protection of the installation. It could be argued that as it located "at source" that it should be a type 1 but you generally see those on LPS installations, See the BS EN 62305 series.

Thank you for bringing this to my attention, I hadn't seen this before.
(In my view Type 1 would be overkill unless it was an overhead supply that is likely to be directly hit by lightening.)

EDIT Mind you at £122 + vat that's 2/3 of the cost of changing the board to a Fusebox SPD board with RCBO's anyway.

 

[Lister1987]

Mind you at £122 + vat that's 2/3 of the cost of changing the board to a Fusebox SPD board with RCBO's anyway.

Fair observation, there may be others by other brands but the Wylex one immediately came to mind as we're familiar with the ubiquitous REC2 isolator.

 

[bro8284]

Its getting crazy, as now all rentals need smoke detectors and to fit the new detectors (New circuit or alteration of lighting circuit) we need to install SPD, that's going to add £100 + to the job just on materials. the clients/landlord are going to think we are taking the ----. as we know most landlords are tighter than a ducks .......,