Extending a Ring Circuit

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So question is New.
Before we move onto "New", as I said before you are choosing to quote the BS7671 definition of "a circuit", but I don't know why you think thi was what was in the mind of those who wrote the legislation requiring notification (in England) of the installation of a 'new circuit'.

The BS7671 definition itself has not, at least in my opinion, been properly through. Even forgetting the issue of FCUs (the failure to 'exempt' which I personally believe was probably an oversight), it really ought to define a "circuit" as being those things protected by the same most downstream OPD - since, as literally written, it could be taken to mean not only that everything in an installation was "one circuit" (protected by the cutout fuse but even that everything i every installation on the same phase in a street was also just "one circuit" (protected by the OPD at the substation/transformer.

As for 'New', as I implied, I think that virtually everyone (probably including the hypothetical Courts which you so much love to talk about!) has a fairly clear common-sense view of what the word means, along the general lines of "the appearance of something which was not previously present".
As as to Part P, is it a law or a regulation?
"Part P" is actually "Part P of The Building Regulations 2010", which is a Statutory Instrument produced by the Secretary of State under powers bestowed on him/her by The Building Act 1984 - hence very much "a law".

However, as we know, that "Part P" is simply one sentence, which says that electrical work has to be undertaken 'safely'. Nothing more - and certainly nothing 'specific'.

Kind Regards, John
 
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It’s a new circuit.

In the unlikely event that you ever get to do an installation certificate you will find that when you install a consumer unit it will have its own certificate.
A certificate for the house consumer unit, another one for the garage, etc.
So, as you add circuits they (by definition) they are new circuits. Each with their own characteristics, each needing testing and therefore, to be street legal, needing notification to LABC.

EDIT
and after reading the post by @JohnW2
You seem to have a tame electrician who appears to be willing to sign his reputation away by saying that your work is his.
Probably better if you ask him/her the answer to this question, and any future queries?
You interpretation of “new circuit” is the opposite to John’s in this case?
John’s explanation would suggest that as long as it is tested appropriately, notification may not be necessary. As things stand, I intend to test this using my own MFT and the electrician can then run his own tests and sign off. Perhaps an electricians sign-off is not required afterall?
Surprised that there is a divergence of view on something like this.
 
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You were talking about this
UPDATE: I have a run in a new and separate RFC for my 3 double sockets.
This is absolutely a new circuit and requires notification.

Then you confused everything by throwing in this curved ball
How would adding a new Circuit on a Garage Consumer Unit (using an existing MCB on main CU) be treated?
That is where there is a difference of opinion.

Going back to the work in hand.
New wiring and sockets, new ring final circuit, new MCB in the house consumer unit is a NEW CIRCUIT.
Requires notification to LABC by the electrician who carried out the work. No matter that you have your own test equipment.
If you find a member of one of the CPS (NICEIC,etc) to notify work that you have done and that (by your admission)
has been designed on the Internet,
installed by you,
tested on a second hand (probably non-calibrated) MFT giving results that you probably don’t know how to interpret

Then he/she is going against the terms of their CPS registration. They are ONLY permitted to notify their own work, not work done by others.
 
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You interpretation of “new circuit” is the opposite to John’s in this case?
I wouldn't really say that, since I presented both viewpoints. As you will remember, what I wrote was ..
Good question...
Some will argue that ....................
Others (probably including myself!) will argue that ........................
So, not 'black and white'. I know my personal view, hence what I would do myself (with a reasonably clear conscience) - but that's just me, and others have to decide for themselves.
I do not doubt that the former of the viewpoints I mentioned (i.e. TTC's) is the more common, being an attempt to take literally what the regs actually say. However, I imagine that (nearly!) all of them have to 'adapt' what is actually written inBS7671, because of the 'FCU issue' - i.e. I don't think that (m)any would believe that adding things to an existing circuit via an FCU constituted 'creating a new circuit' (hence notifiable). Apart from anything else, even in the pre-2013 days (and still the case in Wales) extending an existing circuit with an FCU was one of the very few things that was not notifiable. It would surely make absolutely no sense for it to have been intended that the "major relaxations" (in England) of notification requirements in 2013 would result in something previously not notifiable becoming notifiable?!

If that is one's view of an FCU, it's hard to see why it would not apply equally to a fuse (or MCB), with or without a switch, within some enclosure which was not called an "FCU" ... and it's not hard to extend that to a situation in which there are two fuses (or MCBs), in paths to different loads, within some enclosure - which is getting remarkably close to what would be sold, and regarded, as a 'mini CU' (e.g. 'garage CU').

So, as I said, and particularly if one wanted 'consistency' and 'electrical common sense'[, the situation is (at least in my opinion) not "black and white" - but I suppose that, much as one (at least, I!) can debate/'argue', the 'official answer' e.g. (as one would be expected to produce in an exam) is probably the one offered by TTC.
John’s explanation would suggest that as long as it is tested appropriately, notification may not be necessary.
That was just one of the two viewpoints I presented and, as above, I would imagine that it is probably the minority one!

Kind Regards, John
 
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You were talking about this

This is absolutely a new circuit and requires notification.

Then you confused everything by throwing in this curved ball

That is where there is a difference of opinion.

Going back to the work in hand.
New wiring and sockets, new ring final circuit, new MCB in the house consumer unit is a NEW CIRCUIT.
Requires notification to LABC by the electrician who carried out the work. No matter that you have your own test equipment.
If you find a member of one of the CPS (NICEIC,etc) to notify work that you have done and that (by your admission)
has been designed on the Internet,
installed by you,
tested on a second hand (probably non-calibrated) MFT giving results that you probably don’t know how to interpret

Then he/she is going against the terms of their CPS registration. They are ONLY permitted to notify their own work, not work done by others.
The two are not mutually exclusive. The “new” circuit is being added to the Garage CU. The Garage CU is protected by an MCB and RCD on the main CU.
 
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The two are not mutually exclusive. The “new” circuit is being added to the Garage CU. The Garage CU is protected by an MCB and RCD on the main CU.
Yes, but I think the view of TTC (and many others) is that "a CU is a CU", regardless of how it is supplied, If one takes that view, then the garage CU "is a CU" and, as such, any new circuits added to it would be notifiable.

I have presented other ways in which people might view the situation, but more on the basis of common sense and attempting o second-guessing the intent of those who created the rules, than in relation to what the rules 'actually say'.

You will be aware, from what I've written, that I think a literal (e.g. TTC's) interpretation of the rules can result in 'anomalies' (in relation to 'common sense') - but that does not, in itself, mean that that interpretation of theirs is 'incorrect'.

As I've implied, if you want to avoid these issues/arguments, it's often possible do things in the garage/wherever in such a manner that no-one could seriously suggest that anything there was a "CU" - and hence everything would be an extension of the house circuit, not 'new circuits' :)

Kind Regards, John
 

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