TT system.

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and you are making a statement that they are legally binding documents?do what you want,

I'll laugh when you go to court and try to use that as a defence for killing some innocent person through your incompetence

typical of the dont care just pay me attitude that is dragging our trade down, while everyone else suffers due to your john wayne attitude.
Compliance with the wiring regulations will go a long way to proving competence, should there be any dispute, and is far from being a 'John Wayne' attitude.

As the 'diagram' is scanned from 'Guidance Note 8', and the leaflet is from the IEE 'Wiring Matters', I would say that they comply with the 'Regs'.

How can you expect anyone to take your theories about running an earth to an outbuilding above the guidance given by electrical engineers - you really are funny!

 
Compliance with the wiring regulations will go a long way to proving competence, should there be any dispute, and is far from being a 'John Wayne' attitude.As the 'diagram' is scanned from 'Guidance Note 8', and the leaflet is from the IEE 'Wiring Matters', I would say that they comply with the 'Regs'.

How can you expect anyone to take your theories about running an earth to an outbuilding above the guidance given by electrical engineers - you really are funny!
as you say GUIDANCE

you have to use your own knowledge and experience to assess if the guidance is relevant in your given situation,

its not a be all and end all.

you make the decision, and you are the one responsible for the safety of the people, NOT the person that wrote the guide,

do you think the guy that wrote the guide to USA is going to take responsibility for all the idiots that go there?

NO. only an idiot would think he would,

he wrote a guide,

NOT a LAW

YOU make the decision as to what you decide is safe, but ultimately you make the choice,

complying with BS7671 will/may help your defence in court, but it is NOT a TOTAL defence, BS7671 is NOT law or in any form a legal document.

YOU alone are solely responsible for ensuring that you have left the installation safe.

 
..... a defence for killing some innocent person through your incompetence
And I've just Googled 'innocent person killed through tn-c-s earth to outbuilding' - and guess how many hits I got? ?:|

You're not funny, after all - and I'm bored now.

I've offered plenty of documentary evidence, phone calls to the DNO, the IET........You have offered nothing to support what you say and yet STILL you insist that you are right.

I give up. I have nothing more to say on this matter.

People can make there own minds up.

 
The argument will carry on all I will say on the matter in my experience is this if you are in the EDF area and you put a supply to an outbuilding they will not connect it up they will insist on you making it TT you can argue all day about whats in BS7671 or any other thing they will not give you a supply. Now unless there is a reason ie unable to get a rod in I always make outbuildings TT they are seperate to the main house or where supply comes from and too me they are a seperate installatiion and earth should not be shared as far as I am concearned thats what I do. I am happy with this and unless somebody can tell me why I should not do this I will carry on.

 
mr gs asked a question of the learned members

for the most part

the resultant posts have been

argumental

contradictory

and utterly useless to the op question

i note that mr dog has made one request

i shall now make another

cool it

thankyou

mr smith

 
because its not,its distributed by a concentric cable, and unless you live in an inner city there are lots of instances where its not PME, and if it is then why are my PFC readings so different?

the resistance between N&E on a true PME should be neglible, its the same cable spiked all the way back to star point,

do I need to do a drawing to show how PME differs from TNCS.?
If there are lots of instances where it is not PME, you should contact the DNO responsible, and point out that they are in breach of ESQCR2006.

Suggesting that the resistance between Neutral and earth should be negligable is ridiculous and obviously judging from the OP incorrect.

Do the drawing if it pleases you, but how does it relate to the fact that any form of TN-C-S other than PME is ilegal, and is not recognised by BS7671?

 
If there are lots of instances where it is not PME, you should contact the DNO responsible, and point out that they are in breach of ESQCR2006.
places with their own 11KV transformer may be TNCS, but not PME. DNO is not in breach of ESQCR.

 
If the DNO is distributing the TN-C-S without PME, then they are in breach of Regulation 9(2) of ESQCR2002.If the equipment belongs to the consumer, then they are in breach of Regulation 8(4) of ESQCR2002, and the DNO is in breach of Regulation 9(4) of ESQCR2002.

Either way the DNO is in breach of ESQCR2002.
I dont have an ESQCR about at the minute so if you want to quote me the reg I'll happily read it,

but would that be similar to saying a 6mm earth is unacceptable simply because it doesnt comply with BS7671/2008, but was fine under 15th.?

I dont know, I'm only asking.

 
I dont have an ESQCR about at the minute so if you want to quote me the reg I'll happily read it,but would that be similar to saying a 6mm earth is unacceptable simply because it doesnt comply with BS7671/2008, but was fine under 15th.?

I dont know, I'm only asking.
I believe spin is refering to the following passeges:

General requirements for connection with earth8. - (1) A generator or distributor shall ensure that, so far as is reasonably practicable, his network does not become disconnected from earth in the event of any foreseeable current due to a fault.

(2) A generator or distributor shall, in respect of any high voltage network which he owns or operates, ensure that -

  • (a) the network is connected with earth at, or as near as is reasonably practicable to, the source of voltage but where there is more than one source of voltage in that network, the connection with earth need only be made at one such point;
    (B) the earth electrodes are designed, installed and used in such a manner so as to prevent danger occurring in any low voltage network as a result of any fault in the high voltage network; and
    © where the network is connected with earth through a continuously rated arc suppression coil, an automatic warning is given to the generator or distributor (as the case may be) of any fault which causes the arc suppression coil to operate.
(3) A generator or distributor shall, in respect of any low voltage network which he owns or operates, ensure that -

  • (a) the outer conductor of any electric line which has concentric conductors is connected with earth;
    (B) every supply neutral conductor is connected with earth at, or as near as is reasonably practicable to, the source of voltage except that where there is only one point in a network at which consumer's installations are connected to a single source of voltage, that connection may be made at that point, or at another point nearer to the source of voltage; and
    © no impedance is inserted in any connection with earth of a low voltage network other than that required for the operation of switching devices or of instruments or equipment for control, telemetry or metering.
(4) A consumer shall not combine the neutral and protective functions in a single conductor in his consumer's installation.

(5) Paragraphs (1) to (3) shall not apply to a network which is situated within a generating station if, and only if, adequate alternative arrangements are in place to prevent danger.

Protective multiple earthing

<A name=9>9. - (1) This regulation applies to distributors' low voltage networks in which the neutral and protective functions are combined.

(2) In addition to the neutral with earth connection required under regulation 8(3)(B) a distributor shall ensure that the supply neutral conductor is connected with earth at -

  • (a) a point no closer to the distributor's source of voltage (as measured along the distributing main) than the junction between that distributing main and the service line which is most remote from the source; and
    (B) such other points as may be necessary to prevent, so far as is reasonably practicable, the risk of danger arising from the supply neutral conductor becoming open circuit.
(3) Paragraph (2)(a) shall only apply where the supply neutral conductor of the service line referred to in paragraph (2)(a) is connected to the protective conductor of a consumer's installation.

(4) The distributor shall not connect his combined neutral and protective conductor to any metalwork in a caravan or boat.
Section 9 is only relevent where PME conditiona apply so if its not PME then section 9 will not apply (although I fail to see how the reference to 9(4), i.e. a caravan or boat, is applicable). Also its unlikely 8(4) will apply either as if they have been conbined, it was probably done by the DNO even if it was done on the consumers equipment.

Sorry spin but your argument does not seem to hold water. It is not illigal for a DNO to supply TN-C-S without being distriubuted from a PME network.

 
Sorry, I don't want to be seen as argumentative.However the Regulation applies whenever the distribution is TN-C, or as stated at the start of the Section, when "the neutral and protective functions are combined."
But ahead of that the whole of section 9 only applies to PME networks. The distinction of TN-C is only made when referring to TN-C-S supplied from PME rather than TN-S supplied from a PME network.

 
Considering that the Section is headed Protective Multiple Earthing, then yes you are quite correct, it is only relevant where PME conditions apply. However Ian, please read the section. Especially the part at the begining.

"9. - (1) This regulation applies to distributors' low voltage networks in which the neutral and protective functions are combined."

Unless you believe that TN-C-S does not have the neutral and protective functions combined, it is quite obvious that PME conditions do apply and the Section is relevant.

 
But ahead of that the whole of section 9 only applies to PME networks. The distinction of TN-C is only made when referring to TN-C-S supplied from PME rather than TN-S supplied from a PME network.
I'm sorry Ian, but what exactly does your statement mean?

Are you stating that the requirement to provide PME only applies when the distribution is PME?

That's like stating wet is wet, only when it's wet.

 
I think you misunderstand what I am saying. If a network is PME then this section is relevent and 9(1) just states that its only relevent for TN-C-S presentations on PME not something else (Like TN-S or TT).

 
I think you misunderstand what I am saying. If a network is PME then this section is relevent and 9(1) just states that its only relevent for TN-C-S presentations on PME not something else (Like TN-S or TT).
I think you misunderstand the Regulation.

This Regulation informs when PME is required, and that is whenever the distribution is TN-C.

 
I think you misunderstand the Regulation.This Regulation informs when PME is required, and that is whenever the distribution is TN-C.
Thats not how its written. If the network is not PME then 9 is not applicable at all.

The logic is simple.

First decision, is it PME [YES|NO].

If YES then continue to itterate this section.

If NO then continue to section 10.

 
This may be clearer.

All motorcycles have 2 wheels therefore all 2 wheel vehicles are motorcycles.

That assumption is incorrect is it not?

Just because that section you mention (9(1)) applies to all presentations that are both PME supplied and TN-C-S presented, it does not logically follow that all TN-C-S are PME in the same way you can not say that all PME supplies are TN-C-S presented as they can be TN-S, TT or something else.

Is that clearer?

 
Thats not how its written. If the network is not PME then 9 is not applicable at all. The logic is simple.

First decision, is it PME [YES|NO].

If YES then continue to itterate this section.

If NO then continue to section 10.
The heading is: "Protective Multiple Earthing."

The Regulation starts by informing when it applies, ie. where the neutral and earthing functions are combined.

If you look at other Regulations, ie. (5) Inspection of Networks.

This particular Regulation requires that inspections are carried out, and that records of those inspections are kept.

Using your logic, if no inspections are carried out, the Regulation does not apply.

 
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