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Quoting for some work following a recent eicr question looks like in a couple of occasions that they have spared of the 2.5mm ring with 4mm cable half a dozen times it has been coded a c2. There maintenance guy has said this isn't a fault as the 4mm cable is ok on a 32amp breaker what's your thoughts code or no code i have suggested we install it back on the ring and that I'm quoting from the eicr. thoughts please.
 
Not sure I quite understand.

so 2.5mm^2 ring - then single (single or double socket outlets) fed off at various points on the ring forming single point radials?

So no multiple sockets (socket to another socket etc) off any one point of the ring?

if that's the case in general it could all be done in 2.5mm^2 no need to be 4mm^2 at all and nothing wrong with it.

Why has it been coded a C2 - what's the regulation breach that they associated with it on the EICR?
 
Smacks of code 'rip the customer off for unnecessary work', to me. Either that or the apprentice did the test on a Friday afternoon.

Absolutely nothing wrong at all with what you describe.
 
How is a spur off a Ring final circuit wired in 4mm twin and earth a C2 observation? How is it likely to become dangerous? Has the tester inspector provided any reasoning?

An EICR is checking for compliance to BS7671, not coding because it’s unusual, or “I wouldn’t have done it that way”! In my opinion any coding needs to be backed up by at least one regulation from the wiring regs that it is breaching. Not just an opinion that it is wrong.

Is it due to the terminations of both 4mm stranded and 2.5mm solid conductors into the terminals of a BS1363 accessory? In which case I may tend to agree this MAY breach 526.2 among other regs.

4mm T&E in its self on a ring in my opinion doesn’t breach any regs. 433.1.204 states RFC must be wired in AT LEAST 2.5mm copper conductors with AT LEAST 20a Iz (except micc). So 4mm T&E complies.

Recently I have come across a fair amount of coding which are at best a bit weak and at worst blatant fishing for work. Coding such as “C2 requires metal fuse box upgrade - plastic dangerous”. “C2 kitchen light not waterproof”.

I’m not sure how others who have been asked to do remedial works overcome this. Most individuals I haves spoken to are not likely to get another full EICR? (As it’s likely just a paper exercise for their letting agency).

I have sometimes retested the circuit in question (As in my opinion any one who has done this won’t have tested properly). And then issue a minor works for the circuit stating test values and regulations as to why it is compliant with the regs. This way the customer can keep the MWC as they would if any actual remedial work had been carried out.
 
its a 2.5mm ring main spured off to 6 socket outlets using a 4mm t&e can only persume the guy thinks you cant spur of a spur so he has given it a c2. but the cable can take the load so not ideal but cant see what regulation. its broken
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its lazy testing in my eyes when they dont quote a regulation next to there coding.
 
so are you saying, there is one spur connection to the ring that feeds 6 sockets?
if so, its non compliant.

if there are 6 spurs off different parts of the ring feeding 1 socket each then it is compliant.
 
yes it looks like they have spured off 1 socket 6 times using 4mm t&e
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westwald says method c on test sheet but not attended site yet. quoting from test sheet but will attend site to see properly later this week.
 
its a 2.5mm ring main spured off to 6 socket outlets using a 4mm t&e can only persume the guy thinks you cant spur of a spur so he has given it a c2. but the cable can take the load so not ideal but cant see what regulation. its broken
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its lazy testing in my eyes when they dont quote a regulation next to there coding.

Well that is non compliant, it does go directly against the regs.

However, that doesn't mean it's a C2, as the 4mm^2 cable should be capable of 32A (subject to installation method) so non-compliant, but safe is C3 for me.
 
Assuming ref method C for the 4mm...

Can anyone tell me what regulation this doesn't comply with?

I haven’t got my copy to hand, however, Although I don’t think it is explicitly written. I would argue that 433.1.204 and appx 15 state that the reason a 32a OCPD is allowed on a RFC is that it is unlikely that at any point on the Ring final is likely to exceed 20a.

By installing 6 x sockets connected to one point, and no further over current protection, it more that likely is going to be able to overload the 2.5mm on the shorter leg of the ring. So even if the 4mm is installed method C and rated to 32a, the 2.5mm could become the sticking point. Even if the ring was perfectly balanced with equal legs, is the spur fed from a BS1363 socket outlet - with terminals rated to 20a.

For me it’s a difficult one to code. I’m leaning towards a C2 insufficient/inadequate cable sizing. But would not argue to much if someone had coded C3. Fairly easy fix with a switched fused connection before The first socket either way.
 
Assuming ref method C for the 4mm...

Can anyone tell me what regulation this doesn't comply with?

I know i am not quoting a reg for you, will be a little while before i am home to open the book.

however, i recall that only one spur is allowed from each point on a ring under the standard definition of an RFC

it is not about the current capacity of the radial part of the circuit so much as the capacity of the terminal at the socket where the spur is made off.

when you think about a ring circuit, any terminal on the ring is going to be subjected to a maximum of 16A on a 32A ring.
if you put a spur on that could carry......(hmmm, thinking)

as i am working this out, i am struggling to find a good technical reason why it is dangerous.

going to look at the book when i get back and see if this is just a case of (we have always done it like that, so if its not like that then it must be wrong)
 
Appendix 15.

And if the 4mm^2 is downrated to less than 32A it would also breach 433.1 (and be a C2)

Unfortunately I can remember that it was regulations A35 and A40 - in the 14th edition! But you were allowed two outlets on a spur - A40 but not greater than the number of sockets on the ring -A35.

Sad I remember that, but it was a key question in the exams of the day!
 
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Thanks for the replies. I query this because I cannot find a regulation that it automatically breaks.

Appendix 15 isn't regulation, it's a design guide for ring finals. Sticking to it will ensure compliance, but deviating from it does not AFAIK automatically mean non compliance.

I can see how it increases the likelihood of overloading a leg if the spur point was located close to the board down one leg, so 433.1.204 would be broken. But I'm not sure this would be a problem if the spur point was close to the mid point of the ring. I assume the current would divide itself up between the 2 legs, just as it might if there was a cluster of sockets actually on the ring, situated around the mid point.

The terminals of the sockets must be able to take more than 20A, otherwise a 32A radial supplying sockets wouldn't be allowed.

There is nothing in App 15 or the OSG to say that more that one spur cannot be taken from the same point on the ring (although the OSG mentions limiting the total number of unfused spurs to no more than the number of sockets + fixed equipment on the ring). A similar situation could be created by, eg, spurring 2 double sockets off a double socket on a ring. AFAIK this would be compliant with the design guide, but would still create a heavily loaded point on the ring.

Just to be clear: I'm not looking for an excuse to install this way, I'm just interested in the details of our trade, particularly where ring finals are concerned
 

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