Poll - Ring final circuits with high integrity earthing

[deadshort]

That was my first reaction - but that's what most sockets I buy today have - but it sounded as if DS was talking about something 'special'!

OOI what sockets do you buy? I only really ever use 3 brands, and they all have one L+N and 2 Earth (of which, I only ever use one)

Oh sorry - I didn't read, think or write carefully enough! What I should have said was that most sockets I buy have 2 earth terminals (since that's what's relevant to this discussion) - but, as you say, they only have one L and one N. It's years since I saw one of these offered for sale (although I still have a few tucked away):

Untitled

• JohnW2
• 29 Oct 2011
• 6

However, although they're nice to install, I'm not so sure about them safety-wise - at least in a ring final. With a ring final, if one of the L's or N's come's adrift, the user will be none the wiser (everything will still 'work' - unless the 'adrift conductor' touches something it shouldn't!), but the circuit's cable could get overloaded.

Kind Regards, John

I fail to see the point you are trying to make ? A wire

However, although they're nice to install, I'm not so sure about them safety-wise - at least in a ring final. With a ring final, if one of the L's or N's come's adrift, the user will be none the wiser (everything will still 'work' - unless the 'adrift conductor' touches something it shouldn't!), but the circuit's cable could get overloaded

That's how I feel about ring finals regardless of how they're terminated in the socket outlets

However, although they're nice to install, I'm not so sure about them safety-wise - at least in a ring final. With a ring final, if one of the L's or N's come's adrift, the user will be none the wiser (everything will still 'work' - unless the 'adrift conductor' touches something it shouldn't!), but the circuit's cable could get overloaded

That's how I feel about ring finals regardless of how they're terminated in the socket outlets

Yes, I realise that is one of the downsides of ring finals. However, if one is going to have them, then those sockets with 2xLand 2xN terminals must increase the chances of a break in the L or N ring going unnoticed - so (unless there are compensating factors, which there might be) they must be, statistically speaking, 'less safe' than those with only one L and one N terminal (particularly if the two conductors are twisted together ).

Having said that, I seriously doubt whether a cable with a CCC of 20A would come to any harm, let alone cause a fire, if it were carrying 32A continuously (which is not going to happen in practice, anyway) - and if, as is more common, the cable has a CCC of 27A, then an 'overload' of 32A clearly isn't going to result in any catastrophes.

Kind Regards, John

Where did you get your'e statistics form JW2? As i have only ever found one manufacturer using the "six terminal method".

DS

 

[JohnW2]

Where did you get your'e statistics form JW2? As i have only ever found one manufacturer using the "six terminal method".

And whoever manufactured the ones I have (per piccie posted) didn't want to own up to it - because they bear no indication of who made them!

I obviously don't have any statistics, and I've said nothing which was based on statistics. My comments were merely based on obvious facts. If in a ring final, one of the Ls or Ns comes out of a terminal in a "6 terminal" socket (and doesn't touch anything it shouldn't!), there is essentially a zero probability that the householder will become aware that anything has is wrong. If an L or N comes out of a standard ('4 terminal') socket then there is at least some non-zero probability (probably not all that low) that both conductors will come out, so that the householder will become aware that one socket has 'stopped working'. Since "non-zero" is greater than "zero", there is, statistically speaking, a greater probability that they will become aware that something is wrong if a break in the L or N ring arises if there is only one L and one N terminal.

Kind Regards, John.

 

[deadshort]

I must be living in a parallel universe …… is anyone else in John's world?

Kind regards,

DS

 

[JohnW2]

I must be living in a parallel universe …… is anyone else in John's world?It's

I don't really understand your problem. I would call it common sense, but it would also be taught in "Probability 101" or "Statistics 101", so presumably you didn't do either of those courses.

If one thing has an essentially zero probability and something else has a finite (i.e. non-zero) probability, then the latter is more likely to happen than the former. Simples.

Kind Regards, John

 

[deadshort]

I must be living in a parallel universe …… is anyone else in John's world?It's

I don't really understand your problem. I would call it common sense, but it would also be taught in "Probability 101" or "Statistics 101", so presumably you didn't do either of those courses.

If one thing has an essentially zero probability and something else has a finite (i.e. non-zero) probability, then the latter is more likely to happen than the former. Simples.

Kind Regards, John

Room 101, we like that ………

 

[ban-all-sheds]

I only spotted this by chance, as basically I have stopped reading what you write on this subject. Amusing as it is to read things like this:

I think that even BAS accepts that the radial with its CPC converted into a (one) ring is compliant as HIE, so (whatever the regulations "actually say") it makes no sense that the identical situation with a ring final would be unacceptable as HIE.

which confirm that you are so unable to think logically that you actually think it makes sense for HIE to require the increased integrity of a different cpc topology for one type of circuit but not another, and in fact that it is nonsense to require it in one sort when required in another.

Anyway - this is not an attempt to discuss it with you, or to change your mind - that would be pretty pointless as you've already made it quite clear that you could not care less if I am right.

However, in this particular case BAS's attempt to exercise "blind adherence" with wht he feels the regulations "actually say" would actually result in decreased hazard, since there would be four protective conductors (which he would call "two CPCs") connected to each socket in an HIE ring final circuit!

I would be obliged if, when discussing it with others, you would not keep on making out that I am drawing some bizarre distinction between "protective conductor" and "circuit protective conductor".

I have already told you that that is not the case, other people have told you it is not the case, and I and other people have pointed out that that is actually what you have been doing.


And a quick whizz through looking to see if you were misrepresenting me anywhere else turned up this (but it was only a quick look through, so maybe I've missed even more):

Do you mean 6 'earth' terminals? (even BAS only needs 4!)

No, not 4, 2.

But then you know that.



It seems that as well as ignoring what is written in the Regulations you are now ignoring what I write. Presumably you care equally little what that actually is.


I really think it would be best if you would confine yourself to expressing your opinions and discussing with other people what those are and what they write, rather than introducing incorrect assertions of what I have written.

 

[JohnW2]

However, in this particular case BAS's attempt to exercise "blind adherence" with wht he feels the regulations "actually say" would actually result in decreased hazard, since there would be four protective conductors (which he would call "two CPCs") connected to each socket in an HIE ring final circuit!

I would be obliged if, when discussing it with others, you would not keep on making out that I am drawing some bizarre distinction between "protective conductor" and "circuit protective conductor".

No problem - I'll call them anything you like, if you can suggest what. We know that you regard two rings as "two CPCs". I would hope that we can also agree that, if one has two such ring CPCs, there will be four "somethings" to connect to each socket (presumably two into each of two terminals). What would you like me to call those "somethings", if not "protective conductors"? I can't call them "CPCs" without causing confusion, since you say there are only two of them, but I am talking of things of which there are four.

What would you like me to call them?

Kind Regards, John

 

[333rocky333]

Do you mean 6 'earth' terminals? (even BAS only needs 4!)

No, not 4, 2.

But then you know that.

To be fair
With the socket style DS was refering too you would need at least 4 earth terminals as there intention was too use 1 core per terminal

 

[EFLImpudence]

If I may:

You could call them wires as, in the diagram, there are five wires making each of the two circuit protective conductors (or just protective conductors) just as there must be five wires making the line conductor and the neutral conductor.

 

[ban-all-sheds]

What would you like me to call them?

You can call them whatever you like - after all, you are Humpty Dumpty.

All I'm asking is that you stop making false claims about what I call them.

 

[JohnW2]

If I may: You could call them wires as, in the diagram, there are five wires making each of the two circuit protective conductors (or just protective conductors) just as there must be five wires making the line conductor and the neutral conductor.

Maybe I'm just getting paranoid! Knowing BAS's sensitivities, I did consider that, but, the the electrical context, "wire" is just sloppy/colloquial terminology for what electricians would call conductors, so I though he might criticise that, too. In electrician-speak, I was certainly talking about 4 conductors needing to be connected to (presumably two) earth terminals at each socket. I could have just have called them "conductors", but would probably then have been criticised for imprecision (since they could be L, N or E conductors) - so I decided to call them 'protective conductors' (which is what they are) and, as you have seen, get criticised for that, too!

The phrase "can't win" comes to mind!

Kind Regards, John

 

[JohnW2]

All I'm asking is that you stop making false claims about what I call them.

All I said ("claimed") was that you would call two separate rings "two CPCs". If that is now a 'false claim', does that mean that you have changed your mind about that?

Kind Regards, John

 

[securespark]

You can call them whatever you like - after all, you are Humpty Dumpty.

You can't help it, can you?

 

[ban-all-sheds]

All I said ("claimed") was that you would call two separate rings "two CPCs". If that is now a 'false claim', does that mean that you have changed your mind about that?

Well - maybe I was putting too much store by my memory of this:

As I wrote yesterday, I think one of the confusions is resulting from the fact that BAS seemingly perceives a difference between "Protective Conductor" and "Circuit Protective Conductor", accepting that the former represents "A path" back to the CU (hence there are two), but regarding the latter ('CPC') as referring to the entire ring of protective conductors (with joints) - in which case there is only one. Where he got those different 'definitions' from, I haven't got a clue.

If the rings in question are cpcs then I would call two separate ones "two cpcs". Or even "two individual cpcs"

 

[ban-all-sheds]

You can call them whatever you like - after all, you are Humpty Dumpty.

You can't help it, can you?

You really have lost me.

Can't help what?