230 volts
bonding and the resistors are just red herrings, This
less than 50 volts, well less than 46 volts, the actual value would need the resistance of the body. The right hand 15Ω can really be ignored, it is a near short circuit when compared with bodies resistance.
What is more of a problem is earth to earth.
Maximum is 230 volts, with no loss of PEN detection, with loss of PEN detection it says limit is 70 volts, but anything other than a car limit is 50 volts.
As to loss of PEN detection, seems a little daft for it only to disconnect the car, whole house needs disconnecting, however we have no way to disconnect the whole house, even if we know there is a fault, all we can do is switch off the lives (line and neutral) we can't disconnect the earth, we have not got that option.
So we are looking at a risk assessment, which has the highest risk, IT, TT, TN-S, TN-C-S? Back to the 80s the TN-C-S was OK, as all homes used around the same amount of power, so loss of PEN would cause the earths to have a potential between them, but that potential should not be that high.
Today we are looking at a massive difference between what homes use in the same street, and when we get some item's auto disconnecting when out of voltage range, then even worse, my home at the moment is using around 650 watts, but none of that is being drawn from the grid, if the voltage goes under or over the limit, the inverter will cut out. If it goes over, its cutting out will help as the home's load will reduce the voltage, however if it goes under however it will make it worse, the EV charging point will be the reverse, it is really quite simple TN-C-S is no longer fit for purpose.
What we would need is a Smart meter to connect the earth and neutral not hard-wired, and if the voltage is not within limits the meter will disconnect all three connections, not only the lives, but also the earths.
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