2 ring finals on one RCBO

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Today I helped with an EICR in an empty 2 bed rental flat, the landlord was in attendance and started saying he didn't want any failings, my boss explained he only does genuine reports. However what the landlord meant was he wanted any required work done before the report written.

Other than several broken/faulty accessories we found 4 wires in the 'sockets' 32A RCBO and a 32A RCBO for 9.5KW shower which was originally labelled 'kitchen power'. After tests we realised 'kitchen power' had simply been moved over into 'sockets', we converted it into one bigger ring with choc bloc.

What are others views?
 
OK.

One maintenance company I worked for demanded that 6 milli shower circuits were limited to 32A, where a board change was made after fire or overheat damage.

Not sure what would have happened with showers on 4 Milli.
 
I dont like seeing more than what i call 1 circuit in a mcb etc and always assumed it was bunching circuits, however nowadays people tend to say however many are bunched in now automatically becomes 1 circuit
 
That was my argument with an NIC spark who insisted my colleague's addition of another socket at the origin of a 16A circuit was contrary to regs.

I pointed out it was mentioned in the OSG, which he said he did not recognise.
 
I dont like seeing more than what i call 1 circuit in a mcb etc and always assumed it was bunching circuits, however nowadays people tend to say however many are bunched in now automatically becomes 1 circuit
I don't have an issue with several radials starting from an OCPD, or a ring final and a spur, in fact I have both of those situations at home.
However in this case it was 2 ring finals (with the way I edited my OP I didn't make that clear) which feels like it doesn't fall within the rules. Electrically it was fine, fully protected etc, Boss was adament. Truthfully I'm on the fence.
 
What are others views?
My view is that Joining rings end to end, particularly if one of the rings is a kitchen ring is likely to create a very lopsided ring with the attendent risk of overloading one of the ring legs.
 
My view is that Joining rings end to end, particularly if one of the rings is a kitchen ring is likely to create a very lopsided ring with the attendent risk of overloading one of the ring legs.
Very good point. But no different to a single ring with kitchen at one end.
 
In terms of EICRs, the electrical safety council best practice guide says.

Amendment 1 to BS 7671: 2008 no longer requires
departures from the requirements of the current
edition of BS 7671 that do not give rise to danger or
require improvement to be included in condition
reports

I think that applies to the "double ring" circuit, even if it doesn't technically comply it's not any less safe than a circuit that does comply.
 
I seem to remember appendix 15 showed you could take a spur from the consumer unit direct, but the unwritten rule is no more than three wires in a terminal, and this is where I see the problem, two 32 amp radials in a RCBO means two wires in each terminal, but two 32 amp ring finals means four wires in each terminal which may result in one wire not being clamped well enough.

Using terminal blocks with link bars would allow one wire for each terminal. However if doubling up due to din rail length this is not going to help.

The problem with an EICR is you know in 10 years, may be less, it is going to be done again, so if you allow some thing untoward it is going to be picked up. I have not seen a claim going back 10 years, but I have seen on change of ownership court case claiming the previous inspector had not reported faults. (The case was brought by Pembrokeshire County Council Trading Standards and heard by Judge Huw Rees at Merthyr Tydfil Crown Court on Monday 20th September 2021) it seems the electrician admitted he did not do a good EICR so really no option but find guilty.

However not sure what would be the result if one reports the faults, but classes them as code C3?

I remember my son telling me how his bosses wanted a failure with every EICR as then they could say, it failed so no point continuing with the inspection. Yes I know this is wrong, the idea is the person commissioning the report can use it to decide the next step, so need to know all required to bring up to standard, however to do 4 EICR's a day, plus travelling, one has to cut corners, he got out as quick as he could.

So we have the big question, if I do XYZ could in the future a claim be made costing custom or money? We all cut corners from time to time, we hope they do not come back to bite us. A device one inch within the zone limits in a bathroom for example is unlikely to cause a danger, but if some pedantic inspector says it needs moving resulting in re-tiling job, it can become expensive.

Remember the EICR inspector is not worried about how much to correct the error, however he should not be looking for non compliance, but for potential dangerous or worse.

Potential dangerous of doing what? Harm personal, or harm equipment? or both of course. It seems we are lawyers looking at use of English language, rather than electricians, if there is a potential danger of a voltage spike taking out a £1000 worth of equipment, unless fitted with a SPD is that a potential danger when doing an EICR?

I watched a long winded video where some were saying lack of SPD in a commercial premises was a code C2.

So two ring finals on one RCBO is OK as long as done in a way so no more than three wires in a terminal. Which in turn depends on how much room inside the CU, and if the manufacturer allows the use of what ever you use to join cables within the CU.
 
Because of the new definition of 'non-compliance', you really have to distinguish between comply and conform.

If something does not give rise to danger it cannot by definition be a non-compliance.


As with so many things, in future we will never know at first reading what is actually meant.
 

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