Requirements for RCD protection on a 32a Socket supplying Mobile Equipment

C2 is the guidance from Electrical Safety First's BPG4: https://www.electricalsafetyfirst.org.uk/media/2149/bpg4-1.pdf 

See page 16, 4th item down.

Sparkingchip said:

Why was the 32-amp socket installed and why is it being used to supply the cabin, instead of the cabin supply being hard wired?

What type of premises is it installed at and how are the premises and the cabin used?

Good question, but if it was designed as a mobile & Transportable unit ... a number have a BS EN IEC 60309 series appliance inlet fitted to them.

aligarjon said:

I might be misreading it but it seems to say an RCD can be ommitted with a documented risk assessment in this sort of situation.

Not according to Regulation 411.3.3, this is item (iii) usage, and the risk assessment exception applies only to (ii).

lyledunn said:

Perhaps if those trotting out code 2’s were asked to fully explain the potential danger, there would be less of them issued. Blind code hugging must be a significant burden to British industry!

Yes, although if it's a metal-framed or container-type mobile/transportable unit, I wouldn't be happy without RCD protection, given the risks of rodent damage. That said, as aligarjon  pointed out, would a different selection of cable/connection type be more appropriate, particularly if the cabin is going to be there long-term ... especially considering this case: www.independent.co.uk/.../turney-sue-logan-fire-calder-vale-b2843032.html

"which investigators said could have been caused either by a carelessly discarded cigarette end or an electrical fault relating to wiring leading to a freezer"

So, £350k for a possibility?

Whilst it was not done properly, where is the proof that this caused the fire? Could it not also have been a fault in the freezer itself?

Never happy to see poor installation, but also not happy to see people convicted by "it might have been".

"which investigators said could have been caused either by a carelessly discarded cigarette end or an electrical fault relating to wiring leading to a freezer"

So, £350k for a possibility?

Whilst it was not done properly, where is the proof that this caused the fire? Could it not also have been a fault in the freezer itself?

Never happy to see poor installation, but also not happy to see people convicted by "it might have been".

keylevel said:

Never happy to see poor installation, but also not happy to see people convicted by "it might have been".

Not a conviction, but essentially a dispute between the neighbours' insurers as to who should pay for the loss to the neighbouring property. So, balance of probabilities applies.

I am unimpressed by the judge's reasoning as to the standard of care required by an ordinary householder: §§ 112 - 122. He refers to Part P at § 120 and BS 7671 at § 121, but clearly an extension lead is not part of the installation, so out of scope of both.

The reasoning appears to be that the defendants were negligent because they failed to call in an electrician either to install a permananet circuit, or inspect the DIY arrangement.

There must be plenty of similar lash-ups around the country and this one had lasted 13 years, which must have seemed reassuring to the householder. There is, however, no mention of an EICR during that period.

Judgement available here.