Transportable Building EICR coding/reg question

[Slurps]

Hi all,

Just carried out an EICR on a transpotable classroom. Trying to decipher a reg to see if something is compliant. 717.411.1 States automatic disconnection of supply shall be provided by RCD not exceeding 30mA, now does this refer to the site supply (which cannot be certain due to location changes) or the protective device within the consumer unit? CU currently has a 100ma RCD as main switch protecting 3 circuits, AC, sockets, lighting. I know the socket circuit will require some form of 30mA protection but don't know wether to recommend changing the main switch to 30mA due to this reg or fitting RCBO for that circuit alone. Either is fine but just want to be correct in my recommendations and reg references for the cert.

Also while I'm here, discovered a strange set up to the socket circuit too. The socket circuit feeds one 'unfiltered' outlet via 16A radial, which then goes on to feed various other 'filtered' outlets in the unit via a plug top and lead from this initial socket. There is evidence of previous use of UPS but from what I can see this has been bypassed and no signs of any 'filters', just directly supplying the outlets via 3 compartment trunking. Now I know this is really not good practice, but is it compliant? Everything is protected correctly, other than the 30mA protection stated in the first issue. Outlets supply 20+ pieces of computing equipment. Not sure how to write it up if at all.

Sorry that went on a bit! Look forward to hearing your thoughts.

Thanks

 

[spary]

The supply means just that, where it's fed from and not in the CU as the incomer wouldn't be covered.
Too early to answer the rest just yet. :13:

 

[richy3333]

It needs to be remembered that this is a special location per 7671. I'd say the 30mA RCD needs to be in the CU of the unit. I'd read supply in this instance to mean supply to the circuit. The main incoming supply to the transportable unit could be from anything - grid, generator, Jedi?

 

[spary]

It needs to be remembered that this is a special location per 7671. I'd say the 30mA RCD needs to be in the CU of the unit. I'd read supply in this instance to mean supply to the circuit. The main incoming supply to the transportable unit could be from anything - grid, generator, Jedi?

looking at 717, I think you're right but supply to me means the incoming cable

 

[westward10]

Reg 717.411.1 is a bit tricky to follow but does state Supply and further refers to Reg 717.313(ii) for said supply. So I am certain it refers to the supply outside of the unit.

 

[spary]

Well you would think so, but not looking at the diagrams

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[westward10]

what plans

 

[spary]

?

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[westward10]

Diagrams.

 

[spary]

What about them?

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[westward10]

Doesn't matter.

 

[spary]

in two minds about this now,
for me 'supply' means cable going to the unit, so 717.411.1 should be applied but should maybe be stated as RCD at "origin" of supply
although the figures in 717 all show RCD inside the unit.

I replaced a CU inside a old BT cabin last week and achieved ADS with a 30mA RCD at origin of supply with 60898s in CU

 

[westward10]

Yes I agree supply would be the incomer, like the supply to your house. From looking at the Diagram there is only one 30mA rcd but it does not isolate all supplies in the unit. So it must be referring to the point of source?

 

[westward10]

Probably not relevant now but just been through old 16th Editions and 30mA is only mentioned in the current version. The diagram is generally the same, maybe the diagram in the current version needs expanding to clarify the location of this rcd.

 

[richy3333]

If I were you I'd follow what westward10 suggests. He's great at interpreting the Regs and has decades of experience, so he's your man

Sorry I've just remembered this is a question relating to an EICR and also a query regarding a 30mA RCD. Just mark it down for FI. Jobs a good'en!

 

[spary]

If I were you I'd follow what westward10 suggests. He's great at interpreting the Regs and has decades of experience, so he's your man

Sorry I've just remembered this is a question relating to an EICR and also a query regarding a 30mA RCD. Just mark it down for FI. Jobs a good'en!

I shouldn't laugh, but I'm going to, hahahahahahahahhaahhhaa

 

[westward10]

Now now children don't let your minds wander they are probably too small to be out on their own.

 

[Nightmare1308]

I no this is an old post but,
A problem that would arrise is discrimination, if it's then fed via a circuit with 30mA protection and 3 circuits protected via 1 RCD.
As you have said it's transportable so unless it's connected to a sorce you can't report on what's not there.
Also when it's then Relocated it must be tested again which then it will be picked up on with the next tester.
They might be leaving the 100mA in for fire, fault protection and not additional.
In my opinion I would LIM what is not there and provide a separate write up or a risk assessment stating addtional protection may be required and would need FI when connected to a source?
Like you already said sockets will need addtional protection
Aircon would be if has outside unit etc
Lighting may not need it depending on installation method, outside fittings and special locations?

Look forward to some feedback?

 

[Gnasher]

It is my understanding that the EICR is for the transportable classroom and will remain in force for the period of the certificate and not the source of supply as it will be plugged into multiple locations that may or may not have a 30ma RCD.

 

[Nightmare1308]

Is this report being carried out before its moved or after? If not how can you assure connections won't come loose while being transported?
No different to a caravan as its only valid till its moved?