Statute Law Reference Preventing TN-C in consumers installs

[Sidewinder]

Hi all,

I'm trying to find the official statute law reference disallowing TN-C in a consumers install.

Anyone help please?

Just been through ESQCR 2002, 2006 & 2009 could not locate it.

Next is 7671.

Need it ready for tomorrow morning if anyone feels they can help!

---------- Post Auto-Merged at 19:25 ---------- Previous post was made at 19:23 ----------

Just found it, should have used 7671 first!

Reg 8(4)

 

[johninlondon1]

Surely Regulation 8(4) of the ESQC Regulations (2002) and not BS 7671. Which states "A consumer shall not combine the neutral and protective functions in a single conductor in his consumer

 

[Sidewinder]

Yes John, but I went through ESQCR & missed it as it is less than 2 lines, but, in 7671 it is indexed & cross referenced straight to ESQCR 8(4)

 

[johninlondon1]

I understand thought u meant 8(4) of bs7671 and was confused, lol

 

[Evans Electric]

Was it in the EWA also. ? Its in the BRB definitely .

 

[Sidewinder]

It is in ESQCR 8(4), did not check EAWR after finding it in there TBH.

 

[kerching]

Sidewinder...welcome to the forum. Please take a few moments to introduce yourself and do not be afraid to ask questions. Most answers can be found in the copy of BS7671 which I would advise you to purchase............ :run ................ :run ................. :coat

...sorry, been a long day. Took a day off to drop kitchen ceiling [lath and plaster]...filled a skip. Finding black dust in places I have not seen for years!! where does all this black s4!te come from????

 

[Technician]

LOL...have made a few notes from this... ut the kettle on

 

[johninlondon1]

Looked through EaWR 1989 and couldn't find direct references to TN-C.

 

[Evans Electric]

TN-C also not permitted for agriculture and horticulture premises 705-411-4

 

[meerkat]

Hi Sidey,

543.4 Combined protective and neutral (PEN) conductors

543.4.1 Pen conductors shall not be used within an installation except as permitted by regulation 543.4.2

Note: In Great Britain, regulation 8(4) of the electricity safety, quality and continuity regulations 2002 prohibits the use of PEN conductors in consumers installations

543.4.2 The provisions of Regulations 543.4.3 to 543.4.9 may be applied only:

(1) where any necessary authorisation for use of a PEN conductor has been obtained and where the installation complies with the conditions for that authorisation, or

(2) where the installation is supplied by a privately owned transformer or convertor in such a way that there is no metallic connection (except for the earthing connection) with the distibutors network, or

(3) where the supply is obtained from a private generating plant.

page 132 (Brb)

HTH (MEERKAT)

 

[Sidewinder]

Thanks Meerkat,

I found the references ready for the meeting this morning, but, the brb/bgb is not statute law.

I was convinced it was in there, but was not sure it cross referenced to statute, hence the Q as I had failed to find it in ESQCR where I thought it was.

Panic over anyway as the client had the wrong end of the stick.

Not a good machine design, but, it was not PEN anyway!

 

[Evans Electric]

I've worked on two jobs done to TN-C , as an apprentice. Both had Home office permission as I remember.

(Job 1.) 24 storey and 3 storey Halls of Residence at B,ham University .

Interesting , but strange . Carried out in concentric 1 core MICC with earth tail pots . Metal dist. boards with no neutral bars just earth bars .

To connect a socket went thus:- Flush box with pot clamps - centre core = L earth tail must not be cut , so green sleeving as far as the box term

then black sleeving as far as the N , then green sleeving where it loops from N to E .

( Job 2) New depot for the old MEB (Midlands Electricity Board) DNO all wired in a dreadful flexible, butyl rubber, concentric braided carp . Braid had to

twisted and sleeved then connected in the same way as above .

Strange , reminded me that the MEB were testing Bedford transit type vans on battery power and were proving to be sucessful , late 60s , wonder what happened to them ?

 

[Technician]

Echoing Meerkat and Sidewinder; have read Gn 8; page29

where the PEN conductor issue is addressed. The reg 546.02.01

does not exist, but the essence of 543.2 is stated and ESQCR

is also included in connection with the exemption from the ban

on CNE conductors in user premises.

Hope this helps.

 

[Sidewinder]

Echoing Meerkat and Sidewinder; have read Gn 8; page29where the PEN conductor issue is addressed. The reg 546.02.01

does not exist, but the essence of 543.2 is stated and ESQCR

is also included in connection with the exemption from the ban

on CNE conductors in user premises.

Hope this helps.

Where did the reg 546.02.01 come from?

BTW EQSCR is sufficient proof for my point, and the client agreed anyway, as it turns out there is no CNE on the supply anyway, it is just a control system on the machine transformer derived, with one leg earthed, very common and acceptable.

 

[Technician]

Sidewinder; good point. When I was doing my NEBOSH the trainer,

in a discussion, introduced the "quasi-legal dosument", a document

that while not being statutory may contain absolutes and these can

be spotted when the word "shall" is used.

For this reason I have always looked at BS7671 in this light and make

this point to anyone who might choose to disregard it.

 

[Sidewinder]

There are I'm sure examples of the "qusi-legal-document" in my NEBOSH course notes, but I would have to check, I'm not sure that 7671 was one of them, however, I think that it could be argued that way.

My query is with the reg no.'s it is not a critical one, those you have quoted are referenced where?

Did you find them in GN8?

Please remember GN8 is a brown version, there is never was a "red" version, nor is the green yet available.

So, if you are saying that a reg referenced in GN8 is not in the brb, then this may well be so, however, it is probably in the brown book.

I am only surmising and I would have to check my references, as they are not here.

I am having my dinner and surfing before going back to work!

 

[Technician]

Sidewinder I found this in Gn 8 the green book and it was not

updated to the new amended edition.

I looked for that reg; could not find it.

 

[Technician]

Gn 8 Page 29

Re TN-C systems;

This system type is very infrequently used in the UK.

Reg; 546.02.01 of BS 7671 restricts the use of an installation

PEN conductor to circumstances where;

as required by ESQCR the consumer has obtained an exemption

from the ban on CNE conductors in the installation or;

The source is a privately owned transformer or generating plant

or other source and connected in such a manner that there is

no connection with the public distribution system.

 

[Sidewinder]

Sidewinder I found this in Gn 8 the green book and it was not updated to the new amended edition.

I looked for that reg; could not find it.

Gn 8 Page 29Re TN-C systems;

This system type is very infrequently used in the UK.

Reg; 546.02.01 of BS 7671 restricts the use of an installation

PEN conductor to circumstances where;

as required by ESQCR the consumer has obtained an exemption

from the ban on CNE conductors in the installation or;

The source is a privately owned transformer or generating plant

or other source and connected in such a manner that there is

no connection with the public distribution system.

Technician,

There is no GN8 related to the 17th Ed at all.

The current version of GN8 is a 16th version, yes it has a green cover, they all will, the 8 is in a brown circle.

They never updated GN8 to the red book, they are currently updating it to the 17th Amd1, it is due for publication in April 2012.

You have misread and mis quoted the regs mate, sorry.

You have transformed reg 546-02-01 to reg 546.02.01, the first is a 16th reg, the 2nd is a non existent 17th reg.

The dashes in GN8 are a dead give away that it is a 16th or before reg, as from the 1st Ed. of the 17th the dashes were changed to dots.

546-02-01 refers to 546-02-02 to 546-02-08, and then goes on...

This reg when changing from the 16th brown book to the 17th red book the reg. went from 546-02-01 to 543.4.2 & now refers to regs 543.4.3 to 543.4.9

The wording is similar between the two books, though there are some differences.

There are also some changes between the 17th Ed. red & green books with respect to Reg. group 543.4

I understand the differences in the systems, my request for a reference was urgent as I had to go on site to check out a machine the following morning, that the client stated was using a TN-C system in the machine wiring.

This did not turn out to be the case.

I also did not need to convince the client it was wrong, to have TN-C in their install or their machine, they were very concerned about this themselves.

As it turns out, the system was not TN-C anyway.

There was no N conductor of the supply at the machine it was TP&E only.

HTH.