My Complete DIY Rewire

[JohnW2]

I still can't find it, but there's a document somewhere (HSE? Eurostat? ILO?) that points out that the UK has about half the rate of "electrical incidents" of the next lowest country in Europe. All (as far as I know) of those other countries use radials, so even allowing for statistical errors, we seem to be doing something right.

I find it hard to believe that even you think that such a degree of difference can be explained by the CPC redundancy, which appears to be the only real 'safety advantage' of ring finals - so it seems unlikely that the difference has got anything to do with our use of ring finals. Certainly if you look over the period of our use of ring finals, aren't the more important factors likely to be things like our use of fused, earthed and non-reversible plugs, and shuttered sockets?

Kind Regards, John

 

[stillp]

Yes, you could well be correct. The only other possible advantage of the ring topography might be a reduced EFLI giving faster disconnection times.
Someone said to me earlier today that a loose connection would not have to carry the full load current in a ring, so would dissipate less energy and be lass likely to cause a fire. I'm not so sure of that.

 

[JohnW2]

Yes, you could well be correct. The only other possible advantage of the ring topography might be a reduced EFLI giving faster disconnection times.

Yes but, whether ring or radial, the 'required' (presumably 'deemed to be adequate') disconnection times would be the same, and I very much doubt that reducing the disconnection times below those (already short) figures would make any material difference.

Someone said to me earlier today that a loose connection would not have to carry the full load current in a ring, so would dissipate less energy and be lass likely to cause a fire. I'm not so sure of that.

That's presumably strictly true, but strikes me as 'scraping the barrel'!!

Kind Regards, John

 

[stillp]

Yes, you could well be correct. The only other possible advantage of the ring topography might be a reduced EFLI giving faster disconnection times.

Yes but, whether ring or radial, the 'required' (presumably 'deemed to be adequate') disconnection times would be the same, and I very much doubt that reducing the disconnection times below those (already short) figures would make any material difference.

It might make a difference for the 5th percentile who are not adequately protected by the usual times. Please remember that the standard times are maxima, not targets, i.e. they must not be exceeded.

 

[333rocky333]

To be fair to the OP can someone start a new thread on this Ring Radial debate.

Although we dont all agree on the Ops actions at least give him some respect and a fair chance on the forum
Thanks

 

[JohnW2]

Yes but, whether ring or radial, the 'required' (presumably 'deemed to be adequate') disconnection times would be the same, and I very much doubt that reducing the disconnection times below those (already short) figures would make any material difference.

It might make a difference for the 5th percentile who are not adequately protected by the usual times. Please remember that the standard times are maxima, not targets, i.e. they must not be exceeded.

If one is to believe the published curves for MCBs, I imagine that, provided Zs is no greater than the 'maximum permitted' (i.e. PEFC no less than that required for operation within the maximum permitted time), disconnection times are probably already dramatically less than the 'maximum permitted' times, leaving little, if any, scope for a lower Zs reducing the disconnection time any further - the curve for a Type B MCB is essentially 'vertical' (at I=5In) from 10 seconds down to the lowest time plotted (0.1 sec in the BS7671 graphs, 0.01s or 0.001s in some manufacturer's graphs). To all intents and purposes, disconnection is 'instantaneous' for any current ≥5In. I'm therefore very doubtful that he modest reduction in Zs which may (not inevitably) result from use of a ring final is going to have any appreciable impact on safety.

Kind Regards, John

 

[JohnW2]

To be fair to the OP can someone start a new thread on this Ring Radial debate.

It's far too late for any of us to do that. As I keep saying, only the mods could rationalise the situation by shifting all of the radial/ring stuff into a different thread.

Although we dont all agree on the Ops actions at least give him some respect and a fair chance on the forum

Fair enough - but, although you may be one exception, I rather doubt that (m)any other people are going to respond to any 'original thread' messages any more, for reasons I've mentioned. AFAICS, 'that' thread is now essentially dead, whether the 'hijacking' remains here or not. Others may disagree.

Kind Regards, John

 

[333rocky333]

Yes but if the thread dies a death, then so be it.
The ops pics and responding comments may help some of the DIY lookers even if they show the way NOT to do things.


Nothing personal john
At least people can choose to bypass the new thread and leave it to the 3 or 4 people who want to discuss it

The OP kindly asked and I respect that

 

[JohnW2]

Nothing personal john ... At least people can choose to bypass the new thread and leave it to the 3 or 4 people who want to discuss it ... The OP kindly asked and I respect that

Yes, I understand that, and I certainly don't take it personally. If I have any 'beef', it's with the mods, not you. In forums in which I have had 'powers', a situation like this will have been 'nipped in the bud' by splitting very early on - then the two split threads would each have been free to flourish or die, according to the wishes/actions of members.

If one does it properly, splitting threads can be a tedious business (increasingly so the longer one delays doing it) - but, as I said, IMO that's one of the most important (and thankless!) tasks which falls to 'mods', or whatever a particular forum may call them!

Kind Regards, John

 

[sparkwright]

This bloke just ignores every bit of advice, isn't interested in professional standards, and will do it his way regardless.

Shame, I thought he might take on board our advice.

I am withdrawing from this topic.

This is what I said. But I am making a temporary return to this thread.

I too would like to see the major discussion on radials and ring circuits removed from this topic, and put into it's own thread.

It's not fair to the op to have pages and pages of this virtually irrelevent subject ruining his thread.

Irrelevent because there's no actual reason why the op should or shouldn't be using rings.

The comments on rings and radials are excellent though, and so should be placed in their own thread.

Both the DIY project and the rings vs radials offer enough interesting info to be revisited again in the future, so they should be made into seperate topics, and can therefore be found again easily.

Though I don't necessarily agree with everything the op does or says, I have to defend his right not to have his topic hi-jacked in this manner.

 

[ban-all-sheds]

They might have been keen to maintain the use of the ring final for sound engineering reasons, they just didn't bother to explain their reasoning to you.

Yes, they might have been.

And they might have decided to keep those reasons a secret when they published the document explaining the background to the Amendment.

And it might be that nobody else can suggest any sound engineering reasons which they might have had because they are stupid.

Or it might be that there are no sound engineering reasons.

I still can't find it, but there's a document somewhere (HSE? Eurostat? ILO?) that points out that the UK has about half the rate of "electrical incidents" of the next lowest country in Europe. All (as far as I know) of those other countries use radials, so even allowing for statistical errors, we seem to be doing something right. Remember that although there are no pan-European standards for electrical installations, each country's wiring regulations are derived from a series of IEC standards, so cable ratings, installation methods, and circuit protection are basically the same across the continent.

So if ring finals are so wonderful, and result in fewer electrical incidents, why has not one other country decided to adopt them?

 

[stillp]

It's not fair to the op to have pages and pages of this virtually irrelevent subject ruining his thread.

The discussion didn't ruin the thread, the OP did by his persistent disregard of the advice he was given.

 

[stillp]

So if ring finals are so wonderful, and result in fewer electrical incidents, why has not one other country decided to adopt them?

IHNI.
Perhaps they're not clever enough? Perhaps they're unwilling to change what they've done for decades?
If ring finals are evil, why do so many people still use them?

 

[ban-all-sheds]

Perhaps they're not clever enough?

Is that a serious suggestion? You think that the German/French/etc equivalents of the members of JPEL/64 don't understand ring finals? Or don't understand the data which (according to you) shows that they would improve the safety of installations in their countries?

Perhaps they're unwilling to change what they've done for decades?

Perhaps, but allowing them would not make them compulsory, would it, any more than they are here.

Plus, for that to be the reason it would mean that there were tens or hundreds of groups of professional engineers and standards bodies wilfully ignoring sound engineering judgement instead of just one.

If ring finals are evil, why do so many people still use them?

Because they refuse to think properly about it.

 

[JohnW2]

So if ring finals are so wonderful, and result in fewer electrical incidents, why has not one other country decided to adopt them?

IHNI. Perhaps they're not clever enough? Perhaps they're unwilling to change what they've done for decades? If ring finals are evil, why do so many people still use them?

Given that (as witness al these debates) the arguments for/against are far from clear-cut (or generally agreed), I imagine that no country (including UK) has ever seen a compelling reason to change from what have become established practices in their country.

Kind Regards, John