exporting earth

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Makes sense with what I said earlier about being in contact with the two different potentials.

Thanks for the additional info, Admin.

That's similar to the diagram in GN8, where he gives both options for earthing the remote buildings.

Is there a link for the PDF or has it got to be bought?

:)

 
At the end of the day it's not our Earth or the Customers but the DNO's. If they say you can't do it, you can't do it.

 
No the earth belongs to us all Ian, it doesn't belong to any single organization or entity. That is what were talking about after all. The general mass of earth ROTFWL

On a serious note though, it would seem to me that if you take Mr Stokes statement literally, then neither party is right or wrong. That said, how do you prove that a buildings floor is insulated if it's existing ?:| . It would seem that making it TT would cover your rear end.

 
No the earth belongs to us all Ian, it doesn't belong to any single organization or entity. That is what were talking about after all. The general mass of earth ROTFWL On a serious note though, it would seem to me that if you take Mr Stokes statement literally, then neither party is right or wrong. That said, how do you prove that a buildings floor is insulated if it's existing ?:| . It would seem that making it TT would cover your rear end.
If I'm not mistaken,(I'll have to check), I think GN3 outlines how to test resistance of flooring - can't remember how easy or hard it is, though, not your normal run-of-the-mill test, after all:p

 
If I'm not mistaken,(I'll have to check), I think GN3 outlines how to test resistance of flooring - can't remember how easy or hard it is, though, not your normal run-of-the-mill test, after all:p
All the more reason just to TT and save yourself alot or rear end pain :)

 
Just quickly.

ESQCR has been updated since 2002.

Almost all new (last 15-20 yrs as far as I know) DNO network distribution is CNE, thus effectively providing a "TN-C-S" supply even though they may present it as TN-S to the consumers side.

They have to PME their CNE networks to comply with ESQCR.

So unless you TT you will almost certainly be using a CNE conductor for your earth.

This can bring in many problems and also offer many solutions depending on your view point.

 
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Oh it isn't that long, so here you go.Where installations are supplied from a PME supply it is often impracticable to extent the earthed equipotential zone to remote buildings because of the intervening ground which exhibits a 'true earth' potential. This potential will be negative with respect to the PME earth (at least when some load is being supplied) and for this reason extending the zone would be undesirable.

(Taken from: A Practical Guide to the Wiring Regulations by Geoffrey Stokes)

The guy has many letters after his name :Applaud

Make of the article what you will
I think our Geoffrey has made a little boo boo with terminology there or, there is a transcription error sory Volti.

We are talking about a.c. with UK electrical distribution.

 
Please remember WHY there exists a difference in potential with TN-C-S / PME supplies and apply 1st principles then it can be understood, why it is and is not allowed to be exported.

 
Well Mr Stokes has reworded that paragraph in the latest and updated version of his guide. So either he spotted that or he felt it needed a better explanation.

 
Afraid Geoff has a few up on me!

Eur Ing Geoffrey Stokes BSc (Hons), CEng, FIEE, FCIBSE

Sidewinder, BSc (Hons), MEng, IEng, MIET, TechIOSH

Thus I will have to bow to his superiority!

Not CEng yet, still working on it, time is an issue! :_|

:D :coat

 
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Any proof to back that up??
yes,

and without sidewinders great knowledge,

it would not comply with reg16 EAWR, nor would anyone doing so.

although as sidewinder pointed out ESQCR (?) would not permit it either.

god, its times like this I wish I was smart....

 
Come on Steps, Reg 16 is to do with people not systems.

You'd have a job getting that past a judge!

Mind that's not saying that I disagree that exporting a "PME" earth can be dangerous if incorrectly done.

Oh, BTW I found out today that apparently almost all new DNO distribution nas been CNE/PME for nearly the last 40 years! Source, IET!

 

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