according to Victron, if you have external EHU "plugged in" the the chassis should be bonded to PE / Projective Earth.
as the vans chassis could become live from a mains fault, but not trip the breaker as the van is insulated from Earth due to rubber tyres.
so the risk potential would be a live chassis and someone stepping out onto the ground, then getting a shock.
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I just found this on the interweb...... To comply with BS7671 sect 721 any PERMANENT 240 volt installation in a vehicle (including caravans and motorhomes etc) should have the incoming mains supply earth bonded to the vehicle chassis. It also worth noting that any metal gas pipes should also be...
www.t6forum.com
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you could make a easy UK plug in version.
make up a UK plug with the fuse removed and a single wire connected to the earth pin in the plug. ( wire needs to be fat enough to be able to carry the full fault current back to the EHU post so maybe 2.5mm multi stand?)
then have a wire that's run and bolted to the chassis.
then when mobile camping, if the plug is plugged into to your EHU lead in the van, the vans chassis will be connected to the EHU post( and become a PE earth).
an example of a AUZ plug version below.
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im not a sparks so don't take this as gospel.
@Pauly may be able to advise on the suitability of the earth plug option?
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