Original poster: dave pierson <davep@xxxxxxxx>
Right. The ground impedance is quite variable depending on moisture content. The neutral return wire in a household installation in NZ is typically smaller than the phase feed wire since there is current sharing by design between the neutral wire and the ground stake.
My understanding is that this is forbidden in US practice. The 'neutral' must be the same size as any 'phase'. same-same for the 'ground' wire.
best
dwp