A friend was asking why when his friend was moving a washing machine he
kept getting shocks off it, and did I think there might be something up
with the wiring. Anyway, it sounded like it needed further investigation
so we went round for a peak.
It turns out it is a ten year old house they moved into a month ago, and
the description given by the owners sounds like we are not talking just
about static. So I explained it could be a fault with the earthing in
the kitchen, and that combined with either a genuine hard fault in the
(now disposed of) old machine, or possibly the normal issue of mains
input filters and a poor earth, would explain it.
Plugged a socket tester into a kitchen socket - no earth at all! Loop
tester conformed complete open circuit. So I suggested we inspect the CU
Standing there looking at it, I was thinking "am I missing something
here?". Modern split load CU, TN-C-S head end, main equipotential bonds
in place (even if the water pipe one was undersize)... but no connection
*at all* between the earth terminal on the suppliers cable head end and
Suggested that this was less than optimal and they ought have words with
their supplier PDQ. Repeated earth loop tests on some other sockets and
got a reading of 30 ohms or so (probably just the fortuitous earthing
from the main EQ bonds). (oddly the RCD did not trip even here which
would suggest yet another fault in addition to the circuit fault in the
Anyway the supplier came and looked, agreed with the diagnosis, but then
said they had to get their own sparks to make the earth connection.
(This surprised me a little since I would have expected them to be happy
to make a connection to their head end).
Just shows how useful surveys are in these cases!
- posted 12 years ago