I've descovered that when the earth wire in a domestic electrical install

I've descovered that when the earth wire in a domestic
electrical installation is not connected back to the board
(ground) a voltage of between 9-24v is is found to be
present in the earth wire.
When connected at the board there is no voltage - is this
normal and why does it happen?

Question Posted / alanpoole

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I've descovered that when the earth wire in a domestic electrical installation is not connect..

Answer / prof. dr. k. manjunath

The correct answer is there is no path for the leakage
current. If domestic power consuming power apparatus earth
connection is connected to the board, the correct ground
connection offers zero resistance to the leakage current.
This is the effect that, you noticed zero volts when
connected to the board.

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I've descovered that when the earth wire in a domestic electrical installation is not connect..

Answer / kj

You will find that no insulation is perfect. There will
always be some leakage. As well there will be induction
into the wire because it is run next to the phase and
neutral. Both of these can account for a voltage in the
earth wire when disconnected.
I would expect a higher reading if the voltage was due to
leakage in the insulation. This could be up to phase
voltage but with no current capacity.
I would think the reading is most likely induction. The
voltage here would increase depanding on the current and
the length that the earth was run with the phase and
neutral.
When it is connected to the earth in the board the voltage
is drained away as in both cases there is only negligible
current capacity.