That obviously is what is meant by U0/Ze (or U0/Zs) - but where does that expression for PFC/PSCC come from? Whatever, it seems that you are doing differently from at least some other electricians, who record the PFC/PSCC dsiplayed by their meter (which does not use U0)I use 230 as that is what I think is meant by Uo/Ze (or Zs).
It would, and I've certainly seen nothing like it, either - but the implication of all the regs and testing guidelines, and the existence of OPDs rated above 6kA, presumably implies that these very high PFCs/PSCCs must exist somewhere.I never have - that would mean a Ze of 0.03833Ω
Are you perhaps reading too much into that provision on the form. You seems to be assuming it is a statement of the value which has been used for all calculations, but are you sure that it's not simply meant to be a statement of what the declared U0 actually is - i.e. to distinguish a 1-phase '230V' supply from other supplies?Yes, but as there is only provision for the value to be recorded once. It would seem to me that this figure should be regarded as having been used for the all readings on the certificate.
I'm not sure there would have been any need, would there? The only thing MCBs know about is the current flowing through them and, as we've discussed, the arbitrary change of U0 from 240V to 230V (without a change in supply voltage) obviously would not have changed the current flowing in response to an actual fault, even if some ('silly'!) calculations might think that it had changedI admit that MCBs do not appear to have been altered to allow for the change but, surely, the powers that be must have deemed this acceptable.
You may not see a need to calculate design current, but if you did calculate it using your method, it would have changed with the change in U0. I still question the correctness of 'obeying the MIs' (right or wrong!) without determining design current for yourself and hence determining whether or not the circuit was compliant with 433.1.1(i).No it didn't because, as I have previously said, it is not necessary to calculate for a shower circuit because the MIs state what CPD to use.The current drawn by, say, a particular shower did not suddenly change on the day that 'political' change occurred but, per your views, the design current of the circuit did change on that day.
Of course, but we're into to areas of things that we would not want to discuss in public. I'm quite sure (and think you are as well) that, because of all the 'margins', one could go way into 'non-compliant' territory in relation to all sorts of things and still have a very safe domestic installation. However, as I said, we don't generally talk about such things - and certainly don't advocate/ suggest/ advise them!I do not mean that I would ignore any regulations but it would seem, as is apparent in many topics which you raise, that house circuits in general are greatly over-engineered and very safe.
Kind Regards, John