Recently sat the 18th Edition Course and of the understanding EV Charging points shall be fed from a TT Supply. PME is acceptable only when feeding any other equipment ie Lamp posts Ticket Machines for example and providing Type A or Type B RCD is fitted and the Charger point is then to be separately spiked. Just looking on the attached and a company called Pod Point suggest TN-S is acceptable with no need for an earth spike. Wondered if anyone else has come across this diagram and can confirm TN-S is acceptable without the spike (see - page 2)
Actually reading your description of the transformer and gensets, it sounds to me like one of the few cases where it is always going to be TNS, and you can proceed to use the system earth.
Nothing to stop you leaving a note at the origin saying that the charging points use the TNS earth, and if this is ever changed the earthing of the charge points must be re-visited. In all systems you can bond an additional earth rod to the supply earth at any point, much as you can add a water pipe bond at any point, so you can be TT ready but linked to the TNS if you wish.
Actually reading your description of the transformer and gensets, it sounds to me like one of the few cases where it is always going to be TNS, and you can proceed to use the system earth.
Nothing to stop you leaving a note at the origin saying that the charging points use the TNS earth, and if this is ever changed the earthing of the charge points must be re-visited. In all systems you can bond an additional earth rod to the supply earth at any point, much as you can add a water pipe bond at any point, so you can be TT ready but linked to the TNS if you wish.
