BS 7671 Amendment 3 Consumer Units

I can see Screwfix do Metal CUs but unfortunately they're all unpopulated.

Steel is combustible, as are all metals!

Much depends on how you define "non combustible" - something that does not support flame and does not melt may meet the definition, and so a flame retardant treated thermosetting plastic may well meet the requirement.

The amendment deems steel to be "non-combustible"[1]. It's not clear to me though what if any plastics would count[2]. Or indeed if carbon fibre from the RR factory would do :) Wiring Matters had "There is no published definition for the term 'non-combustible' that aligns with the intent of Regulation 421.1.201."

Of course the drafters may have taken the view "the public don't need to know: we don't want them meddling in these matters; they should just pay a member of one of the guilds".

TLC sell all metal Crabtree ones, very reasonably priced (and the MCBs are rated for use down to 12 volts DC which is why I have some).

It will be interesting to see what they do to create "insulated" CUs for TT installs.

Seems obvious to me: require an insulated enclosure around the metal CU; with no tool-less access of course for consumers so the CU will need MCBs/RCDs/RCBOs with secure, wireless remote control. Just think of the mark-up on parts when you quote for them :)

The amendment deems steel to be "non-combustible"[1]. It's not clear to me though what if any plastics would count[2]. Or indeed if carbon fibre from the RR factory would do :) Wiring Matters had "There is no published definition for the term 'non-combustible' that aligns with the intent of Regulation 421.1.201."

Of course the drafters may have taken the view "the public don't need to know: we don't want them meddling in these matters; they should just pay a member of one of the guilds".

So no pretty cast magnesium enclosures then :)

So no pretty cast magnesium enclosures then :)

Damn, sorry for doing a Harry in the last post, i've jusr re-installed win8 to this pooter, and added windows live 2011 to get a half decent mail and news reader, but i forgot this must be the one that doesn't have the option to indent the original message,

Maybe it was the 2010 version i used before, or something.... bugger it.... can't be arsed to switch to chunderbird or other, so for now i'll try to remember to indent manually till i figure it out.

It is a complete farce, acknowledged by everyone apart from the JPEL64 Committee. There was a podcast last week, which was meant to clarify some of the issues. It didnt, and didnt give any guidance at all on what would or would not comply. Podcast is linked from this page:

All this is due to the increased number of CU fires? All due to the rush to install RCDs and MCBs that catch fire more often than fuses?

No, it's due to poor quality installation on the current crop of poor quality CUs that dont even meet the current British Standard as regards fire rating. (ok, there are a few, but the majority do not comply)

Insulation kits for TT installations inside metal clad consumer units have been available for years.

Also down to the mix and match of materials, where even overtightening is said to cause issues. There is also a case where a supplier had 2 screws for each incomer now has just the one, so cutting corners.

I don't see any Crabtree Dual Split / High Integrity ones?

In fact I don't see any Dual Split / High Integrity metal ones. I presume the bus-bars are such that such a CU can't become a Dual Split / High Integrity one just by judiciously moving/connecting bus-bars and neutral strips around?

I have not yet looked myself. However this was in my inbox today

Crabtree StarBreakers have fixed din rail. You need to chose carefully before buying them.

I'm fast coming to the conclusion I should get "cheap" populated Schneider from Toolsatan that are dual 80A RCD/High integrity and be done with it!

Is there any issue with using a "combustible" CU in a small industrial unit?