'17th CU' thread

[plugwash]

The regs say you should design installations to minimise inconviniance but don't say too much about how far you should go in doing that. IMO like the old split load CU the dual RCD boards that are beoming popular for cheap and nasty 17th edition jobs are bordering on the very edge of acceptability.

IMO the best way to comply with the 17th requirements is to wire with an earthed metal layer for protection and put the RCD protection at the outlet. Unfortunately because crappier methods are widely tollerated RCD sockets and cables with earthed metal layers remain prohibitively expensive.

 

[FingRinal]

Maybe there should have been someone on the committee that asked "WHY" before they introduced some of the new regs. And that goes back to the bonding in the 15th that was dropped in the 16th.

International Harmonization seems to suffer from the same fillibustery hubris as the bizare word of internal diplomacy.

Meetings, wrapped in committees, inside conventions.

 

[sm1thson]

there seems to be two main questions on this thread, firstly the age old question of multiple circuits under the same RCD and weather this sufficient for separation of circuits, but then there is the other question which i read basically as:

where does it say that on a consumer unit change the existing circuits are to be brought up to the current regulations? -I think what BAS is saying is its one of those things that most pros say and do and take for granted but where is it written in black and white as if its that fundamental then surely it should be black and white not just logical.

(i am not saying it doesnt saying just asking for the obvious question to be answered, I have always seen people say it but never seen a source quoted, I am not trying to stir this just put it back on track, it is a genuinely interesting question for me, I am surprised it hasnt been put to bed yet (or i have missed it and people are still going on for the sake of it, which is quite possible))

 

[ban-all-sheds]

where does it say that on a consumer unit change the existing circuits are to be brought up to the current regulations? -I think what BAS is saying is its one of those things that most pros say and do and take for granted but where is it written in black and white as if its that fundamental then surely it should be black and white not just logical.

The regs can't be unambiguously prescriptive about everything - even if that were possible they'd be impossibly large and unnavigable.

But there clearly has to be a limit, or threshold, where you only focus on making sure the work you actually do complies because you either simply cannot do anything about what's already there or it would be utterly unreasonable to update what's already there to the latest standard.

(i am not saying it doesnt saying just asking for the obvious question to be answered, I have always seen people say it but never seen a source quoted, I am not trying to stir this just put it back on track, it is a genuinely interesting question for me, I am surprised it hasnt been put to bed yet (or i have missed it and people are still going on for the sake of it, which is quite possible))

Different people will have different views on where that limit is, and all I wanted to do was to get a range of views and their reasoning....

 

[FingRinal]

I understand the points you've made and how you've managed to decipher the postings.

There have been many of these arguments with BAS time and time again. What is the law? What does this say? What does this mean?

For the first time that I'm aware, BAS finally admitted the tie between the law and the Regs in a post on this forum in the last couple of days.

There are lots of the things the 'Regs' don't make explicit. The same can be said of the 'law'.

One of BAS's thrusts is to take the point 'but where in the Regs does it say that?' and ream off endless points of pedantry to convince (and scare) people into believing if they don't do as he says, they will break the law or else they can do what he says because they won't break the law. He has openly dismissed, condemned and ridiculed such things as BS7671, the OSG, Guidance Notes and his particular favourite the Approved Documents.

Unfortunately (for BAS), his arguments have been repeated across many forums over many years land they cycle and roll like the swell of the Drake Passage.

Reg 131.8 is the starting point for people to look at. After reading the Reg in full, they should apply it to the folowing situation:

I have been asked by a client to upgrade their Consumer unit. I will book the work in and complete the work to the applicable technical, professional and highest personal standards that I can.

A consumer unit affects every protective device, every circuit, every cpc, every protective bonding conductor, the earthing conductor and the meter tails. It's rating and it's loading will affect the supply, the meter, the supply protective device and the supply cable.

 

[sm1thson]

where does it say that on a consumer unit change the existing circuits are to be brought up to the current regulations? -I think what BAS is saying is its one of those things that most pros say and do and take for granted but where is it written in black and white as if its that fundamental then surely it should be black and white not just logical.

A consumer unit affects every protective device, every circuit, every cpc, every protective bonding conductor, the earthing conductor and the meter tails. It's rating and it's loading will affect the supply, the meter, the supply protective device and the supply cable.

Hmm, thats still more logical than black and white but I guess if something is logical enough it is black and white. It does make sense to me that if you change something you have to do it to the current standards and a CU change effects everything as stated, so any reasonably possible work that can be done to bring it up to current standards should be done and departures noted in the usual manner. (i know that reopens the question of what departure (if any) is acceptable but i guess thats where common practice experience etc come in) I can live with that as an answer.

 

[FingRinal]

Despite 'certain' protestations, how you interpret 131.8 (one of the most explicit Regs in the book) may be determined by factors outside of your immediate control:

. are you a registered electrician carrying out paid work for a client?

. which organisation are you registered with - do they have guidelines they expect you to follow as a condition of your membership?

. if you DIY notify - what will the planning officer decide (if you disagree with his decision, how much time and money are you prepared to waste appealing)

. if you DIY on the quiet or do a guvvy on the quiet

As regards a PIR Code 4 for non-compliance with 522.6.6 - I don't believe Code 4 is a blanket code for all observations or defects that comply with a (or the) previous edition but don't comply with the current edition.

It needs more thought. It depends on the significance of the change and the reason for the PIR. 522.6.6 is a major change to improve safety and not a minor change of colour scheme. I would suggest that this is a Code 2 but that it wouldn't on its own render a PIR Unsatisfactory.

If a PIR is carried out for the purpose of a CU change, its purpose isn't simply to excuse non-compliances. It's purpose is to establish compliance or non-compliance with 131.8 and the whole of the 17th, identify the extent of remedial action and to determine if the installation is safe for the alteration.

The assumption of blanket Code 4 is as wrong as the assumption that a Code 2 means 'Unsatisfactory'.

 

[Dartlec]

IMHO this argument shows the problem with the way the new regs were thought through, and more importantly implemented.

The very fact that the On Site Guide has only just become available is indicative. However important the big red book is, the OSG was always a good guide for DIYers wanting to ensure they did things properly, and even for professional installers in giving examples of standard installation methods/situations that could be taken to comply in the opinion of those who publish the regs. (for domestic installs at least)

If the new regulations were crafted purely for sensible, practical reasons based on experience of real installations, the OSG could (should in my view) have been published at the same time as the regs. The fact that it was not suggests strongly that there was a certain period of head scratching as people argued how one might actually comply with the regs that had just been published.

Already I am seeing rather interesting and potentially conflicting advice in some of the literature that has come out since July (The ECA guide is quite an interesting read)

The response of everyone, including manufacturers in developing their 'compliant' products, strongly suggests to me that the 17th was a horse designed by committee. It may or may not be a step forward in electrical safety, but the very fact that a forum like this can sustain a discussion for so long with some valid points (imo) on both sides of it suggests it has some way to go in making things clear.

131.8 is very clear, and very unclear, both at the same time. With a CU change it seems clear that at the very least every circuit needs to be investigated pretty thoroughly. With other less obvious situations I follow the guideline of making sure that I leave nothing less safe than it was when I started the work (and of course ensure the customer is aware of anything that is imo unsafe as it stands, regardless of which reg version it was installed to).

Gavin

 

[THRIPSTER]

How about:-

For any new installations after 1st July 2008, CU installs and changes are required to be carried out to the 17th specification. That means that all of the installation must comply with the 17th edition.

For CU changes on existing installations (and where fitting of a new CU does not compromise the safety of the installation as verified by a PIR) then a CU to the 17th spec may be fitted but leaving the rest of the installation in place. The installer is only responsible for the work he carried out (which includes the test results on the PIR).


Reasoning: (a)you cannot expect a customer to pay for a complete re-wire just because the CU needs changing. (b) the existing installation is not dangerous just because the CU needs changing (c) qualified electricians would not get any work (d) it's common bleeding sense

Analogy: Car goes into garage to have discs/pads replaced - garage states that whole braking system needs to be replaced to bring it up to current regs? Workable - never.

Yours to a cinder


Ash

 

[ban-all-sheds]

For the first time that I'm aware, BAS finally admitted the tie between the law and the Regs in a post on this forum in the last couple of days.

"Admitted"?? I've not said anything here that I've not said in the past. The "tie" between the law and the Wiring Regulations is that following the latter is a way to ensure that you follow the former. That relationship is not at odds with the Wiring Regulations not being mandated in law, nor is it at odds with the view that if complying with them is the choice you make then what you should do does not depend on whether you're a DIYer or a professional.

One of BAS's thrusts is to take the point 'but where in the Regs does it say that?'

I'm sorry that you find asking questions about the regulations, or seeking clarification of them unacceptable.

and ream off endless points of pedantry to convince (and scare) people into believing if they don't do as he says, they will break the law or else they can do what he says because they won't break the law.

Don't be absurd.

He has openly dismissed, condemned and ridiculed such things as BS7671, the OSG, Guidance Notes and his particular favourite the Approved Documents.

I have done none of these things - only stated the reality of the status of those documents. I'm sorry that you find truth and accuracy unacceptable.

Unfortunately (for BAS), his arguments have been repeated across many forums over many years land they cycle and roll like the swell of the Drake Passage.

I guess another way of looking at that is that other people say the same as I.

Reg 131.8 is the starting point for people to look at. After reading the Reg in full, they should apply it to the folowing situation:

I have been asked by a client to upgrade their Consumer unit. I will book the work in and complete the work to the applicable technical, professional and highest personal standards that I can.

Indeed you should, but if there is no explicit technical standard that would be contravened by a particular approach then how far do you go in insisting that your personal standards take precedence over your professional duty to act in your client's best interest? If your client will not or cannot allow you to do what you consider the ideal, then what are the standards you will work to?

All I've been doing here is to ask what people believe those standards to be, and asking them why they believe it, given the lack of explicit direction and given that the "I'm taking full responsibility for everything that's already there" does sometimes seem to be more of a knee-jerk reaction than a genuinely thought-through position.

A consumer unit affects every protective device, every circuit, every cpc, every protective bonding conductor, the earthing conductor and the meter tails. It's rating and it's loading will affect the supply, the meter, the supply protective device and the supply cable.

Indeed, but looking beyond just CU replacement, there are all sorts of jobs where you're working with or adding to or changing what is there where saying "I have to update all that to the 17th standard" may be much less appropriate.

If the job was not to replace the CU, but to remedy defects picked up on a PIR, what would you do if one of the defects was a lighting circuit on a 15A or 30A rewirable? Would you change the fuse or move the cable to a 6A one without adding RCD protection to the circuit?

 

[FingRinal]

Unfortunately (for BAS), his arguments have been repeated across many forums over many years land they cycle and roll like the swell of the Drake Passage.

I guess another way of looking at that is that other people say the same as I.

I shall rephrase...BAS has repeated his arguments over and over again on many forums over many years and they cycle and roll like the inexorable, unchanging swell of the Drake Passage.

And of course BAS....you don't do the job for a living, you've never done the job for a living, you've never been employed in any kind of technical field in any kind of position. You have never the shouldered the responsibility of taking on burden of liability.

As such, you have a 'pie in the sky' approach. The very kind of 'outlook' and opinions that people bemoan of the endless theoretical committees, conventions etc. that nowadays write the Regs.

Quoting half a sentence out of context and refuting/commenting on it is a cheap political trick which may fool some fools some of the time but never fools intelligent people any of the time. And it continues to make your arguments tedious and ultimately irrelevant.

 

[ban-all-sheds]

I shall rephrase...BAS has repeated his arguments over and over again on many forums over many years and they cycle and roll like the inexorable, unchanging swell of the Drake Passage.

And what arguments are they?

And what relevance do they have to the questions I'm asking in this topic?

And in what way are they related to your refusal to answer any of the civil questions I've asked you which are completely relevant to this topic in which you have chosen to participate? Do you intend to contribute anything constructive?

And of course BAS....you don't do the job for a living, you've never done the job for a living, you've never been employed in any kind of technical field in any kind of position. You have never the shouldered the responsibility of taking on burden of liability.

What relevance does that have to the questions I'm asking in this topic?

And in what way is it related to your refusal to answer any of the civil questions I've asked you which are completely relevant to this topic in which you have chosen to participate? Do you intend to contribute anything constructive?

As such, you have a 'pie in the sky' approach. The very kind of 'outlook' and opinions that people bemoan of the endless theoretical committees, conventions etc. that nowadays write the Regs.

Mostly all I've done here (apart from refute your more outrageous accusations) is to ask questions - how can asking questions be "pie in the sky"?

And where I have given my opinions they're actually the opposite - they're in the vein of "let's be realistic about what is practical and achievable".

Quoting half a sentence out of context and refuting/commenting on it is a cheap political trick which may fool some fools some of the time but never fools intelligent people any of the time.

The context is always there for people to see, or remember if they've been following it, and it's immediately accessible as I've not quoted from other topics.

If I do quote part of a sentence or paragraph it's because that's the part I want to reply to, not to trick or fool people, and I wouldn't expect any intelligent person to be fooled or confused by it.

And it continues to make your arguments tedious and ultimately irrelevant.

Well instead of focusing on what you think my arguments here are, why not simply answer the civil and reasonable questions I've asked which are completely relevant to this topic in which you have chosen to participate?

 

[GaryMo]

Ladies, select your weapon of choice......

 

[Pensdown]

IMHO this argument ....

IMO when we started it was a worthwhile discussion.....