Part P assessment question

[telectrix]

That sounds like the Stroma assessor I had last year. He insisted that any outbuilding FURTHER than twenty metres from the main building needed to be TT.

is this the assessor?

 

[Les Dove]

SPOT ON!!!!. LOL

 

[Des 56]

To my mind it seems everybody is wrong
Firstly the assessor for calling it a non compliance of the wiring regs

Its wrong by the op (and everybody else here) for assuming this is a issue about those wiring reg being contravened or not

As far as I understand,there can be dangerous situations created by incorrect use of the supply earthing arrangement

Its a "suppliers" stipulation that Pme not be used outside of the equipotential zone without their permission

That permission should be sought from the supplier in order to do so,otherwise its get yourself a rod and provide your own

The wiring regs will tell you how to cater with whatever earthing is used,it does not give choices of what to do with the earthing provided by others and whether it should or should not be utilised

 

[Deleted member 26818]

So no outside earthed lights without permission from the supplier?

 

[Dillb]

To my mind it seems everybody is wrong
Firstly the assessor for calling it a non compliance of the wiring regs

Its wrong by the op (and everybody else here) for assuming this is a issue about those wiring reg being contravened or not

As far as I understand,there can be dangerous situations created by incorrect use of the supply earthing arrangement

Its a "suppliers" stipulation that Pme not be used outside of the equipotential zone without their permission

That permission should be sought from the supplier in order to do so,otherwise its get yourself a rod and provide your own

The wiring regs will tell you how to cater with whatever earthing is used,it does not give choices of what to do with the earthing provided by others and whether it should or should not be utilised

If thats the case then the DNO should be providing that info when they install the supply or a upto date map online so the information can be cross referenced.

 

[Midwest]

I've seen that line posted a few times 'Distribution Network Operators may forbid their PME earth being exported from the supplied building' (or similar), but I've never seen it actually written in any DNO document?

 

[ipf]

I've seen that line posted a few times 'Distribution Network Operators may forbid their PME earth being exported from the supplied building' (or similar), but I've never seen it actually written in any DNO document?

….never seen anything done about it, either.

Anyone had any resultant problems?

 

[Wilko]

Maybe concerns around a DNO lost N fault causing E rise in both buildings now ?

 

[Midwest]

Supplementary 18th Ed earth rods will sort that

 

[Wilko]

Supplementary 18th Ed earth rods will sort that

I'm not sure how it can. Hopefully I'm wrong, but it seems to me a kettle on a 100 Ohm rod will still pull the touch voltage all the way up. Even 10 Ohms gets to 100V .

 

[Midwest]

I'm not sure how it can. Hopefully I'm wrong, but it seems to me a kettle on a 100 Ohm rod will still pull the touch voltage all the way up. Even 10 Ohms gets to 100V .

 

[telectrix]

we can apply for another sticker for the CU.

"WARNING. THE DNO SUPPLIED EARTH CANNOT BE USED FOR ANY OUTBUILDINGS OTHER THAN THOSE APPROVED BY NICEIC/ELECSA/STROMA/NAPIT/E.T.

 

[Richard Burns]

E.T.?

 

[Dave OCD]

I'm not sure how it can. Hopefully I'm wrong, but it seems to me a kettle on a 100 Ohm rod will still pull the touch voltage all the way up. Even 10 Ohms gets to 100V .

On a 30ma RCD ?

 

[Ian1981]

I'm not sure how it can. Hopefully I'm wrong, but it seems to me a kettle on a 100 Ohm rod will still pull the touch voltage all the way up. Even 10 Ohms gets to 100V .

I think they where looking for a reading of around 20 ohms for the supplementary earth electrode, similar to that of the DNO electrode at the supply end

 

[Dave OCD]

Good luck with that ! Here in Cornwall last week I drove in 2 x coupled 5/8 rods 8 feet in total and got 144 ohms !

 

[Ian1981]

I can’t confirm if that’s gospel but I think that’s one of a number of reasons why it’s been shelved for now anyway.
I heard the 20 ohms figure from an NICEIC webinar.
Yes I said it NICEIC !!
The guys that make the rules

 

[Deleted member 26818]

For street furniture to be allowed connection to the supply PME connection point in the LEB area, it used to be RA of 10 Ohms.

 

[Dave OCD]

All the streetlighting in Cornwall is on PME.

 

[Deleted member 26818]

All the streetlighting in Cornwall is on PME.

Electrode on the penultimate column.