mapj1:
You are correct, if you are interested in touch voltage between the ground outside, and the CPC of the circuit in question.
But unless you have arms like Mr Tickle, or have a bare earthen floor, then this is not the common indoor case - the common case is the victim simultaneously touching CPC of the circuit and also some internal metal that almost incidentally brings something close to the outdoor ground voltage to somewhere within reach, say the bath taps or the gas pipe to the central heating.
IF there is no bonding from MET to the metallic services, the touch voltage would be as you calculate. But with main bonding, the voltage on these objects gets pulled up during fault, so something near the MET voltage, so the voltage across the victim is reduced, often significantly.
mapj1:
You are correct, if you are interested in touch voltage between the ground outside, and the CPC of the circuit in question.
But unless you have arms like Mr Tickle, or have a bare earthen floor, then this is not the common indoor case - the common case is the victim simultaneously touching CPC of the circuit and also some internal metal that almost incidentally brings something close to the outdoor ground voltage to somewhere within reach, say the bath taps or the gas pipe to the central heating.
IF there is no bonding from MET to the metallic services, the touch voltage would be as you calculate. But with main bonding, the voltage on these objects gets pulled up during fault, so something near the MET voltage, so the voltage across the victim is reduced, often significantly.
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