Strange earthing goings on

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Was just in the shower,feet on the wet tiles water all over me and I got
a tiny tingle through a cut in my finger on the tap handle.
So I plodded through house and got an analogue multimeter, back to the
shower, set meter on 10 volts ac, shoved one probe into wet leg and
other on tap handle,2 volts deflection, strange.
After shower I tested between metal floor waste and tap 5 volts.(floor
wastes are not connected metallically to anything but are wet)
Tried between water pipes at heater, nothing,the earth is bonded to main
water copper pipe there is an earth connected to a stake, have not
measured stake resistance but weather has been wet lately so should be
all right.
Might be some nylon olives some where (not at heater anyway (copper olives))
The off peak power was on to the heater at the time.
Might do some Sherlocking tomorrow or sometime.

Re: Strange earthing goings on

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tiny tingle through a cut in my finger on the tap
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set meter on 10 volts ac, shoved one probe into wet
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are not connected metallically to anything but are
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copper pipe there is an earth connected to a stake,
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be all right.
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I had something similar happen several years ago, although the cause is unlikely
to be the same as your situation unless you have old house wiring.
I got a tingle in the shower from touching the taps, it was fairly strong (I was
wet)
so I got out and checked it with the MM. It measured around a hundred volts AC,
but
only a few mA on AC current.
The cause was discovered after we called in a sparkie - the shower had a lead
sheet
tray underneath it which folded up at the sides to contain the shower drainage.
One side of the sheet went up the wall cavity and there was a GPO in the next
room on
the other side of the wall which had rubber-sheathed wiring. The edge of the
lead sheet had
started to cut into the old rubber insulation - which was old and very brittle.
Murphy's
law meant the first wire to be affected was the active, of course. There was
enough
resistance to limit the current, another mm or two and it could have been fatal.





 



Re: Strange earthing goings on
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tiny tingle through a cut in my finger on the tap
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shower, set meter on 10 volts ac, shoved one probe into wet
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are not connected metallically to anything but are
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water copper pipe there is an earth connected to a stake,
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be all right.
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unlikely
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was wet)
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AC, but
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sheet
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room on
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lead sheet had
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brittle. Murphy's
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enough
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fatal.
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In my case the shower tiles are on a concrete floor, the whole house is
on a concrete slab.

Re: Strange earthing goings on
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Used to have that problem in a place where I worked in the 1970's. it
was a stainless sink with the tap attached to it, and copper piping
for the water. Would always get a nasty tingle off of it at certain
times of the day. If you had a cut, or tried to drink from the tap you
knew about it. Connecting sink and pipe to a mains ground fixed the
problem. Never found out the cause, but the same setup is still there
AFAIK.

Re: Strange earthing goings on
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Sounds like a neutral reversal
  do you have a gpo tester ?

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Re: Strange earthing goings on
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One thing that can cause this is a broken neutral so ground ends up being
the return path. Here's a bit of a description:

http://www.electronics-tutorials.com/basics/earth-dangers.htm

You need to watch it because a slight tingle can turn fatal quickly
depending on the impedance, which of course things like moisture and
physical impacts can affect.


Re: Strange earthing goings on
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In my case the taps seem to be at earth potential. it seems that there
is a potential difference between the copper pipes and the shower floor
on the concrete floor slab.

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