When installing a Multiplus II in a UK motorhome with a Lynx distributor and also EHU provision on the motorhome then what is the BS7671 compliant way of keeping mains Earth & DC negative circuits not not passing mains fault current through a same part of a DC negative circuit - they should share the same common ground of the vehicle chassis on separate grounding posts which does avoid creating a circuit merely a shared connection.
The wiring diagrams suggest the inverter earth requires a very thick cable when normally 4mm² would be adequate and it also shows the earth wire connecting to the DC negative busbar which would be correct for a marine craft, but against UK regs for a motorhome. So in essence the supplied diagrams are wrong for a motorhome. Is this fixable perhaps with an amendment or revision?
The incoming mains consumer unit will have the incoming 2.5mm² safety earth conductor connected to the CU earth busbar which in turn uses a short 4mm² flexi cable to connect to vehicle chassis. It would be normal to expect a 4mm² cable from inverter to CU earth busbar to be adequate.
Is there a way to get definitive advice on this query from the Victron technical support team?
Thanks
