This is where we disagree. What constitutes "A CPC" is defined in Part 2, which does not have a separate or different definition for "A ring CPC', and the definition of "A CPC" does not alter because of any regulations.
Do you really think that when 543.2.9 says "
shall also be run in the form of a ring" it is not a regulation defining a mandatory topology for the CPC which is different to that in a radial circuit?
Of course it is not changing the
definition of what a CPC
is, but it is mandating a particular topology which applies to ring circuits and not radial ones.
If there are two 'sets of components' each of which qualifies as "A CPC" before they are joined,
But they don't qualify as a CPC for a ring circuit before they are joined.
On p23 there is a definition of "bonding conductor". Please read it, and note that it says nothing about size, and that therefore a 0.01mm² conductor would meet the definition of "A protective conductor providing equipotential bonding". Then go and read any regulation you choose which covers selection of bonding conductors and explain how it cannot define requirements for a bonding conductor which are not already defined in Part 2.
they can still be regarded as two CPCs when their ends are joined together
They can, if the circumstances are right.
and that remains true regardless of how the L and N conductors in the circuit are arranged.
And that's an example of how the circumstances might not be right - if the L&N conductors in the circuit are arranged as a ring then the circumstances mean that the two CPCs become one ring.
The alternative to that is that you decide that the circuit does not have
a ring line conductor, and
a ring neutral one, it has two line joined together "at the ends" and two neutral joined together ditto. Which makes them parallel conductors, subject to all the requirements in the regulations for those.
Do you have any socket circuits like that in your house, or do you have ring finals taking advantage of the provisions in 433.1.204?
I know you aren't interested in the application of common sense to this situation
On the contrary I am - it is you who is fighting against it.
I am starting with the common sense approach of going by what the regulations say, rather than by disregarding (to the point of not caring a jot) what they say and trying to claim that something other than what they say complies because it matches what I've "interpreted" the "intention" to be.
I am taking the common sense view that if the topology of the CPC providing the protective connection for a radial circuit changes when a high-integrity one is required, then it is rational, not irrational, that there should also be a change for ring circuits.
but, if you were, you would probably see that 543.7.1.203(iii) is calling for two independent paths from each socket to earth
Actually, what I can see when I read it is it calling for two individual CPCs, and calling for each one to comply with all the other requirements for those.
whilst 543.2.9 is (for whatever reason - as I previously suggested, possibly Zs considerations) calling for the protective conductors in any ring final to be arranged as a ring.
Dear god. Do you not take
any regulation you look at "as read"? Does
every one have to be filtered through your "interpretation" of what is "intended", or "called for", even if when you describe that you use words and concepts which appear nowhere in the document? You talk about common sense - why do you not think that it would be common sense for the topology of a CPC to be the same as the live conductors in the circuit it is protecting? Why do you not think that it would be common sense to arrange things so that if the cable was severed, sockets would not be left with L&N but no CPC?
If the Zs was OK, would you use a radial CPC for a ring circuit because you thought that Zs considerations was the reason why 543.2.9 says the CPC must be a ring?
To adapt your phrase, it matters not one jot
why 543.2.9 requires what it does, the
fact is that
it does. Surely you cannot deny that?
So if it requires that
THE CPC of a ring circuit be a ring, what is so unacceptable to you about a regulation saying that two individual CPCs,
each complying with the requirement to be a ring, resulting in there being two rings?
Both of those requirements are satisfied by a 'standard' ring final (with a single CPC ring),
Those will be the requirements you have invented, rather than the ones written into the Regulations, will they?
leaving only 543.7.1.204 ('separate terminals') to be satisfied for the circuit to qualify as HIE
Err... No... I think you will find that still leaves 543.7.1.203(iii) to be satisfied - you know, the one which calls for
two individual protective conductors, not two individual paths.
... but that's merely common sense (and what, I suspect, virtually everyone believes and does),
It is not common sense to decide that the regulations should not be read as written but should be "interpreted" and an "intention" not described by them be taken to mean what they "call for". And it matters not if virtually everyone (or, if this poll is representative, 63.6% of people) think it is - it won't change what the regulations actually say.
As I've said before, your whole position is based on the belief that a standard ring final (with 'separate' terminals') is not already "HIE"
It is HIE.
As long as it is ≥10mm² or ≥4mm² with extra mechanical protection. If not it is not. 543.7.1.203(i) - (iii) aren't that difficult to understand, surely?
(as a radial with 'separate terminals' becomes after its single CPC has been turned into a single CPC ring) - whereas I believe differently.
So you believe that a radial
does have to have the topology of its protective connection changed to become HI, but a ring does not?
You keep talking about "paths to earth", and you believe that to go from standard to HI a radial has to have its number increased, i.e. making its number "high" when compared to standard, but a ring does not have to have its number increased, and that the same number as standard can be called "high"?
And all that is "common sense"?