PME Mains on Private Networks

Question

Am I correct in thinking that on a large site with a private HV network (licence exempt distributor), they can use PME mains for the LV, designed to ENA standards and in compliance with ESQCR? 
 There seems to be a belief that ONLY a DNO can use PME mains. 
 Thanks in advance.

gkenyon · Accepted Answer

Anyone who's not a 'consumer' (who are prohibited from using CNE conductors in their installation Regulation 8(4) of ESQCR) could theoretically use CNE conductors. Does the connection agreement provide a status? However, going forward, embedded generation and G98/G99 connectivity to the grid (whether at HV or LV) may well change the status of someone who thinks they are a 'generator' or 'distributor'. to a 'consumer' .. that might, again, depend on connection agreements.

mapj1 · Answer

A site with private transformers will have parts of the installation that are equivalent to the DNO's LV network, and other bits that are the equivalent of the consumer side. It may not be sensible to use the metering as the demarcation point between distribution and consumption as you would for wiring in the street. 
 In practice on a big site, at least where there are multiple transformers with parallel secondaries that may be independently switched, there have to be multiple N-E bonds and even if not done like the DNO as the full 3 cores 3 phase PEN armour, the link between the NE bonds has to be judged as 'not consumer' for the purposes of ESQCR. 
 The demarcation beyond which N and E are split, never to join again, is then made at the main panel/ breaker 
 Mike.

PME Mains on Private Networks

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