PNB - the new diagrams (3.9b (i) & (ii)) seem confused to me (or at least I'm confused by them). The seem to show the (source) electrode & N-PE link as being part of the consumer's installation - which doesn't seem credible for supplies taken from the grid at LV - on all the PNB systems I've seen the electrode and N-PE link are part of the supplier's equipment (if on consumer's premises), not the consumers installation (and if they were on the consumer's side there would likely be a breach of the ESQCR 8(4) ("A consumer shall not combine the neutral and protective functions in a single conductor in his consumer’s installation."). For the case of a private transformer, yes the link and electrode would be part of the consumer's installation, but then so would the transformer so the whole diagram should be within the dotted box - and in any case that's likely to be simple TN-S.

   - Andy.

I see things more like this:

  - Andy.

Actually, at least on site where more than one LV TX is in parallel you may see multiple  NE links, and it tends to be inside with the TX outside, and then arguably it is part of the consumer side stuff, just upstream of any loads - and I do mean the UK. Note also that the domains of the ECSQR and BS7671 don't overlap - i.e. there are areas of the planet that use BS7671 (Qatar, Malta, probably others ? ) that have no such NE combination prohibition.

But the diagram thing is interesting. I agree that PNB especially is not always clear to folk, even if I think its clear to me.
Perhaps on a related note we should ask DNOs to write in Sharpie on the meter boards what they think the earth arrangement is supposed to be - as they used to have to do  when PME first came out

.
I'm not sure if the standard drawings are inherited from another standard.

Mike.

Actually, at least on site where more than one LV TX is in parallel you may see multiple  NE links, and it tends to be inside with the TX outside, and then arguably it is part of the consumer side stuff, just upstream of any loads - and I do mean the UK. Note also that the domains of the ECSQR and BS7671 don't overlap - i.e. there are areas of the planet that use BS7671 (Qatar, Malta, probably others ? ) that have no such NE combination prohibition.

But the diagram thing is interesting. I agree that PNB especially is not always clear to folk, even if I think its clear to me.
Perhaps on a related note we should ask DNOs to write in Sharpie on the meter boards what they think the earth arrangement is supposed to be - as they used to have to do  when PME first came out

.
I'm not sure if the standard drawings are inherited from another standard.

Mike.