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Electric shock path of current

Newfutile

We all know not to touch a live (line) conductor, but how does the current flow to give an electric shock or perceived electric shock?

Conventional wisdom says its via resistance of the hands , skin and feet but we all wear thick rubber soles and could be on a carpet on a timber floor.

I have done test at 250v DC touching one probe while the other is connected to the MET the meter was unable to detect anything and i felt nothing but i would not try this with AC.

Therefore to me that leaves inductive and / or capacitive coupling.

Does anyone here have any explanation of this effect?

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    Despite conventional wisdom, there is no problem touching a live mains part, so long as you are not in contact with anything else. Standing on an up turned plastic bucket ought to do ;-)

    The hard part really is avoiding the anything else.... If you watch live working crews they are very, very careful to cover N and E wires before sawing into the L.

    In terms of displacement currents, your body capacitance to earth varies a bit with body mass and where you are standing in relation to other earthed items but is typically 500-1000pF for a body well away from earth and not leaning on anything massive,  so the current into you is set by the voltage and 1/(2.pi.F.C) in the normal way.(at 50Hz this is a few j megohms, so the currents are fractional mAs)

    At 50Hz or so the limit for perceived  sensation is about half a mA and limit of no let go about 10-20mA, but it depends quite a bit into which  body part as to how strongly which muscles are paralysed.

    If there is no second contact you need quite a lot more than 230V RMS to reach a significant effect by capacitance alone.

    Mike

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    Despite conventional wisdom, there is no problem touching a live mains part, so long as you are not in contact with anything else. Standing on an up turned plastic bucket ought to do ;-)

    The hard part really is avoiding the anything else.... If you watch live working crews they are very, very careful to cover N and E wires before sawing into the L.

    In terms of displacement currents, your body capacitance to earth varies a bit with body mass and where you are standing in relation to other earthed items but is typically 500-1000pF for a body well away from earth and not leaning on anything massive,  so the current into you is set by the voltage and 1/(2.pi.F.C) in the normal way.(at 50Hz this is a few j megohms, so the currents are fractional mAs)

    At 50Hz or so the limit for perceived  sensation is about half a mA and limit of no let go about 10-20mA, but it depends quite a bit into which  body part as to how strongly which muscles are paralysed.

    If there is no second contact you need quite a lot more than 230V RMS to reach a significant effect by capacitance alone.

    Mike

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