Shed Wiring Question

[ericmark]

I think the like of B&Q is considered as a "shed" where they will sell anything without regard to if used by an ordinary person it would brake any laws or regulations not the garden shed.

There is a problem where it would seem scheme providers had considered using a fused connection unit (FCU) is not making a new circuit under Part P rules even though the BS7671 regulations definition clearly means it does. But until a court case makes case law the definition of a new circuit is open for debate.

In my case supply to shed requires Part P so can't see point in working out what is required in England.

 

[JohnW2]

There is a problem where it would seem scheme providers had considered using a fused connection unit (FCU) is not making a new circuit under Part P rules ...

.... which, of course, is surprising since (in England) it is a view which has the potential to deprive their scheme members of what would otherwise be notifiable work. However, that presumably underlines the fact that they feel strongly that their view is correct.

even though the BS7671 regulations definition clearly means it does. But until a court case makes case law the definition of a new circuit is open for debate. ...

As you say, much debated, but I really don't think that (despite the BS7671 definition - which presumably needs revising) many people believe that there is any doubt about intent. If one took the current BS7671 definition literally, then plugging things into an N-way extension lead would be 'creating new circuits' (and, before someone raises the point, App Doc P indicates that the fact that something is 'plugged in' does not mean that it is not subject to Part P, and associated notification requirements).

Even before the relaxations of notification requirements (in England) in April 2013, adding things to an existing circuit via an FCU was one of the few things that was not notifiable - so I would suggest that it's almost inconceivable that the intent was that the relaxations would result in it becoming notifiable. A court will probably never be asked to rule on this so, in the meantime, I would suggest that we should just work with common sense.

Kind Regards, John

 

[ban-all-sheds]

It's just a simple question about 'Wiring A Shed'.

I understand that you must have a dislike of sheds, why don't you just avoid posts mentioning them?

I would offer advice but, (like others I'm sure) I keep silent, in case you try to drag me down/up to your level..

What on earth has any of that to do with JohnW2's frequent witterings about whether circuits originating from a CU supplied by another CU are circuits or not?

The location of the 2nd CU is irrelevant (as far as I can see - feel free to provide a proper explanation of why you think it's not).

 

[ban-all-sheds]

There is a problem where it would seem scheme providers had considered using a fused connection unit (FCU) is not making a new circuit under Part P rules

That makes no sense - Part P does not have any rules which involve, even tangentially, what is or is not a circuit, new or otherwise. It has only one rule, and that is:

Reasonable provision shall be made in the design and installation of electrical installations in order to protect persons operating, maintaining or altering the installations from fire or injury.

In my case supply to shed requires Part P so can't see point in working out what is required in England.

Compliance with Part P is also required in England - there is no difference.

 

[JohnW2]

What on earth has any of that to do with JohnW2's frequent witterings about whether circuits originating from a CU supplied by another CU are circuits or not?

I 'witter' only because of my quest for consistency and common sense. To use one of your favourite forms of phraseology, are you able to provide "a logical, rational, intelligent and mature explanation" as to what are the significant differences, electrically, between:

1...Two switched FCUs, both fed from the same existing circuit, each feeding various load(s)
AND
2...Two small enclosures, each containing a switch and an MCB (or fuse), both fed from the same existing circuit, each feeding various load(s)
AND
3...One slightly larger enclosure, containing a switch and two MCBs (or fuses), fed from an existing circuit, each MCB (or fuse) feeding various load(s)

To avoid quibbles, you might first answer in relation to the situation in which the MCBs/fuses in (2) and (3) have an In ≤13A, and then tell me if your answer would be different if the In of one or both were >13A.

Kind Regards, John

 

[ban-all-sheds]

No I can't, because there isn't one.

Are you able to provide "a logical, rational, intelligent and mature explanation" of why that means that the law can be disregarded?

 

[JohnW2]

No I can't, because there isn't one.

Do you mean that it is your view that there is, electrically, no significant difference between those three things?

Are you able to provide "a logical, rational, intelligent and mature explanation" of why that means that the law can be disregarded?

No-one is suggesting that the law be disregarded. I am attempting to work out what the law actually requires - or (since the absence of crucial definitions means that almost any interpretation could be disputed/challenged), at least try to guess (with the help of some attempts at logical reasoning) what those who wrote it were trying to require.

Unless/until we can work out what the law requires, or is trying to require, any suggestion of 'disregarding it' is meaningless.

Kind Regards, John

 

[ban-all-sheds]

Do you mean that it is your view that there is, electrically, no significant difference between those three things?

Does "electrically" include the testing required for BS 7671 compliance?

No-one is suggesting that the law be disregarded. I am attempting to work out what the law actually requires - or (since the absence of crucial definitions means that almost any interpretation could be disputed/challenged), at least try to guess (with the help of some attempts at logical reasoning) what those who wrote it were trying to require.

According to the people who wrote it, they were trying to require both the replacement and addition of CUs to be notifiable.

You could always ask them what they intended for circuits, if it isn't obvious enough for you to be sure enough what they intended.

 

[JohnW2]

Do you mean that it is your view that there is, electrically, no significant difference between those three things?

Does "electrically" include the testing required for BS 7671 compliance?

It hadn't really occurred to me that it might (not the least because the law does not require BS7671 compliance) but what would your answers be (with reasons) if "electrically" did, and did not, include that testing.

According to the people who wrote it, they were trying to require both the replacement and addition of CUs to be notifiable.

... in which case that is what they should have written in the law. In this case there is no ambiguity nor any problems due to absent definitions - the law, as written, is very clear in indicating what is (and hence, what is not) notifiable. However, that is not the issue we are discussing.

Kind Regards, John

 

[ban-all-sheds]

but what would your answers be (with reasons) if "electrically" did, and did not, include that testing.

There is a difference in the testing needed for (2) & (3) vs (1), so if "electrically" included it then elecrically there would be a difference.

in which case that is what they should have written in the law.

Indeed, but they didn't.

In this case there is no ambiguity nor any problems due to absent definitions - the law, as written, is very clear in indicating what is (and hence, what is not) notifiable. However, that is not the issue we are discussing.

Oh.

I am attempting to work out what the law actually requires - or (since the absence of crucial definitions means that almost any interpretation could be disputed/challenged), at least try to guess (with the help of some attempts at logical reasoning) what those who wrote it were trying to require.

 

[JohnW2]

but what would your answers be (with reasons) if "electrically" did, and did not, include that testing.

There is a difference in the testing needed for (2) & (3) vs (1), so if "electrically" included it then elecrically there would be a difference.

OK, I think we're going to have to take this is stages, starting with the simplest. If (2) and (3) had fuses, not MCBs (and, to make it even simpler, let's start with those fuses being ≤13A), do (2) and (3) then have have different testing requirements from (1)?

In this case there is no ambiguity nor any problems due to absent definitions - the law, as written, is very clear in indicating what is (and hence, what is not) notifiable. However, that is not the issue we are discussing.

Oh. ....

I am attempting to work out what the law actually requires - or (since the absence of crucial definitions means that almost any interpretation could be disputed/challenged), at least try to guess (with the help of some attempts at logical reasoning) what those who wrote it were trying to require.

Why the "Oh"? The second bit you've quoted I was talking about the (absent from the law) definition of 'a circuit' and 'a new circuit', so we have to guess/deduce the intended meaning. In the former quote I'm talking about CUs (since you raised it) in which case, as I said, there is total clarity in the law as written. It says that replacement of a CU is notifiable - nothing more, nothing less, and nothing ambiguous or undefined.

Kind Regards, John

 

[ban-all-sheds]

OK, I think we're going to have to take this is stages, starting with the simplest. If (2) and (3) had fuses, not MCBs (and, to make it even simpler, let's start with those fuses being ≤13A), do (2) and (3) then have have different testing requirements from (1)?

I believe they do.

Why is the rating of the device relevant? Another thing I believe is that there is no difference in the testing required for circuits which originate from a B6 and those which originate from, say, a B16.

But you aren't going to get anywhere with this - witter on as much as you like about FCUs vs 1-module enclosures with a fuse carrier vs 1-module enclosures with an MCB, they clearly meant something when they made "new circuits" notifiable. So you can either continue to witter on about how the lack of a significant electrical difference between an FCU and a small CU might mean that they did not intend the bleedin' obvious case of a "new circuit" to be notifiable, or you could always ask them what they intended for circuits, if it isn't obvious enough for you to be sure enough what they intended.

Why the "Oh"? The second bit you've quoted I was talking about the (absent from the law) definition of 'a circuit' and 'a new circuit', so we have to guess/deduce the intended meaning. In the former quote I'm talking about CUs (since you raised it) in which case, as I said, there is total clarity in the law as written. It says that replacement of a CU is notifiable - nothing more, nothing less, and nothing ambiguous or undefined.

Indeed. Nothing more or less or ambiguous or undefined.

But, I can assure you, not what they intended. So we have a highly relevant example of the law being worded in a way which does not say what they intended it to say.

Which is why, wrt circuits, I said "You could always ask them what they intended for circuits, if it isn't obvious enough for you to be sure enough what they intended."

 

[JohnW2]

OK, I think we're going to have to take this is stages, starting with the simplest. If (2) and (3) had fuses, not MCBs (and, to make it even simpler, let's start with those fuses being ≤13A), do (2) and (3) then have have different testing requirements from (1)?

I believe they do.

Please eluicidate. I can but presume that whatever difference you have in mind must be essentially 'bureaucratic', since, electrically speaking, the setups are essentially identical in all three scenarios.

Why is the rating of the device relevant?

I don't believe it does, but was attempting to pre-empt any quibbling if the In of the OPD in (2) and (3) was greater than the maximum possible (13A) in (1).

But you aren't going to get anywhere with this - witter on as much as you like about FCUs vs 1-module enclosures with a fuse carrier vs 1-module enclosures with an MCB, they clearly meant something when they made "new circuits" notifiable.

They clearly did - and you have your personal guess as to what that 'something' was. I personally find it hard to believe that they really intended that (as above) the nature of an enclosure(s) used to house switch(es) and OPD(s) used to feed new load(s) from an existing circuit should determine whether or not the addition is notifiable work.

Why the "Oh"? ... In the former quote I'm talking about CUs (since you raised it) in which case, as I said, there is total clarity in the law as written. It says that replacement of a CU is notifiable - nothing more, nothing less, and nothing ambiguous or undefined.

Indeed. Nothing more or less or ambiguous or undefined. But, I can assure you, not what they intended.

When the law is written as clearly and unambiguosly as it is, that is their problem. There's no point in them 'telling us' what that actually intended. If the law doesn't say what they intended it to say, they need to amend that law. Unless/until they do, the law with which we have to comply remains as what it currently says.

Kind Regards, John

 

[ban-all-sheds]

Please eluicidate. I can but presume that whatever difference you have in mind must be essentially 'bureaucratic', since, electrically speaking, the setups are essentially identical in all three scenarios.

If I were to look at the schedule of test results on an EIC of yours, would I find every fused spur listed separately, with a circuit number, and results for all the tests?

They clearly did - and you have your personal guess as to what that 'something' was. I personally find it hard to believe that they really intended that (as above) the nature of an enclosure(s) used to house switch(es) and OPD(s) used to feed new load(s) from an existing circuit should determine whether or not the addition is notifiable work.

Unless, of course, they don't regard an FCU as creating a new circuit.

When the law is written as clearly and unambiguosly as it is, that is their problem. There's no point in them 'telling us' what that actually intended. If the law doesn't say what they intended it to say, they need to amend that law. Unless/until they do, the law with which we have to comply remains as what it currently says.

Indeed.

But OTOH, unless they subscribe to the bizarre-passing-rapidly-through-perverse-and-heading-for-barmy idea that if a new CU is supplied from an existing one nothing originating from the new CU can be considered a circuit, then all of those new things originating from the new CU would be new circuits, and the work would be notifiable anyway. And in any event all of the testing and certification would be the same.

 

[JohnW2]

Please eluicidate. I can but presume that whatever difference you have in mind must be essentially 'bureaucratic', since, electrically speaking, the setups are essentially identical in all three scenarios.

If I were to look at the schedule of test results on an EIC of yours, would I find every fused spur listed separately, with a circuit number, and results for all the tests?

No, you wouldn't - since I don't regard what is downstream of the FCU as being a separate circuit. However, I would say exactly the same if, rather than buying an off-the shelf FCU, I put a fuse (and maybe a switch) in some enclosure of my choosing ... and still exactly the same if I put two fuses (and maybe switch{es}) in some enclosure of my choosing to provide two 'fused spurs'.

They clearly did - and you have your personal guess as to what that 'something' was. I personally find it hard to believe that they really intended that (as above) the nature of an enclosure(s) used to house switch(es) and OPD(s) used to feed new load(s) from an existing circuit should determine whether or not the addition is notifiable work.

Unless, of course, they don't regard an FCU as creating a new circuit.

Exactly, and I don't believe that they do regard an FCU as creating a new circuit, particularly given that adding fused spurs was one of the few things which was not notifiable even prior to the 2013 (in England) relaxations. I think you believe the same - except it seems that you only believe it if one uses an off-the-shelf FCU, and not if one emulates it with a fuse (and maybe switch) and enclosure. Is that what you believe?

Kind Regards, John