Electrical installation in an outbuilding

[ppppenguin]

PME and CNE (combined neutral earth) amount to the same thing. The main earth terminal is conencted directly to the neutral. If you are the only hosue on the transformer then technically it's slightly different but amounts to the same thing in practice. Either way, you mustn't export the earth from a PME system to a caravan. Separate earth rod for the carvan, in other words TT.

https://www.tlc-direct.co.uk/Book/7.9.3.htm