BPG4 Issue 6 lists this as C2 (page 17) plain and simple because of the discontinuous cpc.

Whilst Zs may be OK for disconnection time, you've provided no further information regards csa and type of OCPD, so the thermal effects is still open to question.

Most importantly,  the discontinuous cpc doesn't meet the requirements for protective conductor of an RFC of Regulation 543.2.9 (except if the RFC in its entirety is enclosed in continuos metallic containment that is also used as the cpc for the RFC ... but then it won't be discontinuous?).

BPG4 Issue 6 lists this as C2 (page 17) plain and simple because of the discontinuous cpc.

Whilst Zs may be OK for disconnection time, you've provided no further information regards csa and type of OCPD, so the thermal effects is still open to question.

Most importantly,  the discontinuous cpc doesn't meet the requirements for protective conductor of an RFC of Regulation 543.2.9 (except if the RFC in its entirety is enclosed in continuos metallic containment that is also used as the cpc for the RFC ... but then it won't be discontinuous?).

 sorry - a reader should not be asked to presume [too much :-)]  ... so ...   'presume' a standard domestic 2.5/1.5 t&e rfc circuit on a 32A B MCB    with and without 30mA RCD with let's say nominal 0.45 end to end L & N

having said that  Andy has raised some other good points (hidden things and so on).

interestingly i asked this question many moons ago and at the time it was determined that with all accessible accessories presenting earthed with Zs good etc,   ...    some said that it might/should be only C3   whilst others C2 no doubt   (as in potentially dangerous)    ....      

regards

At the end of the day, the person undertaking the periodic verification is the only person who has seen that particular installation, and it is up to them to make the assessment based on what they have see in that installation alone.

The points we raise here (and the point made in guidance) are, to be fair, only points the person undertaking the periodic verification can take into account in making their decision.

There is no one-size-fits-all answer, experience and attention to detail are key competences for the person undertaking the periodic verification.

of course as acknowledged and is a given.

with respect though, if that's all a discussion delivered, then it would curtail many a discussion on this forum as rarely is anyone else seeing what someone is posting about.  It's just for sharing and the gifted blessed on here I alway appreciate their experience.  Thank you all.

Agreed ... we all learn a lot from participating in this Forum. And the statement regards experience was not meant to be directed at you (or anyone else in particular) ... just an important consideration, that no-one ought to be "proclaiming" at us with fixed rules that are immutable for periodic verification.

psychicwarrior said:

let's say nominal 0.45 end to end L & N

Now we have a bit more information in this perhaps hypothetical situation!

I am struggling so far with the idea that a responsible electrician would just code, "C3" and move on to the next job.

A reasonable starting point would be to do the EFLI test on a sample of sockets i.a.w. Table 3.4 and Note 4 of GN3. If there isn't the expected gentle rise and fall of the values from the DB to the centre of the ring and back, test all of the sockets. Now we know that there is a break in the ring, but it could be line or cpc.

Our electrician has now found that line and neutral are intact, but IMHO we are still at the FI stage.

We know where the break is from the EFLI tests, so now the sockets need to be inspected. If the spiders have undone one of the terminals (or initial verification was incomplete), just put the conductor back, re-test, and no code at all. Everybody is happy for a few minutes' work.

If the terminals of both sockets are satisfactory, I think that the discontinuity of that particular segment of the ring needs to be confirmed.

Only now can we use some judgement and decide which code is appropriate and, depending upon the route of the defective cable, provide a quote for remedial work.

"hypothetical situation"

Nope , it is not !   there are plenty of discussions on the web - it's even been discussed here in the past.

To save providing every parameter of a scenario i had hoped the great and good folk reading to use some faith (but meh what's faith when it's about science they cry )  when reading the question and presume that the protective device was ok with the conductor size(s), Zs good at all points  and so on - all what one could quickly determine without a deep delve into what may or may not be underneath ...  the only issue apparently was that the  circuit was presenting a discontinuous cpc (seemingly at one point for some reason).

After that, then to ask if it was potentially dangerous situation (technically and/or in terms of an eicr  as later commented) or just a case of improve it at some point.    I was curious as there has been split opinion (majority perhaps leaning to potentially dangerous), so I thought I'd see whether that would be the case still.    

Walking away and leaving it as a responsible electrician  is not in the question to evaluate    by the way :-)

If it is an irritating question because of my original lack of details or in any case, I am sorry - it wasn't intended.

If I recall, some of Andy J comments below are not dissimilar to others I have read previously when this issue cropped up.

Good stuff.   Take it easy.

gkenyon said:

Agreed ... we all learn a lot from participating in this Forum. And the statement regards experience was not meant to be directed at you (or anyone else in particular) ... just an important consideration, that no-one ought to be "proclaiming" at us with fixed rules that are immutable for periodic verification.

Absolutely! Interesting turn of phrase…periodic verification. I don’t believe I have seen it referred to in U.K. before although it is what is used in Chapter 6 clause 6.5 in IS10101 2020. I think the regs in Ireland have tighter connections with the HDs.

Might GKs phrasing point to a possible future change in the title of chapter 65? 

lyledunn said:

Might GKs phrasing point to a possible future change in the title of chapter 65? 

Not subliminal messaging on my part. Chapter 65 in BS 7671 is titled 'Periodic verification' in the IEC and Harmonized standards.

And to be honest, it was quicker than typing 'periodic inspection and testing'.


NOW ... my pedantic mind should really have told me that 'periodic verification' is, well, wrong, given the definition of verification in BS 7671 ... compare with the purpose of periodic inspection and testing in Regulation 651.1, and you'll see why (at least in BS 7671) it's not correct to say 'periodic verification'. ('Satisfactory for continued service' whereas verification is about 'compliance with BS 7671'.)

Still, people talk about  'Doing an EICR' ... isn't that  'filling out a form' ?