On 14/02/2020 11:23, TimW wrote:
On 13/02/2020 21:59, TimW wrote:
There was an ancient (1950s) steel pipe bringing mains water into my
house under the front room and then up in the cup'd under the stairs.
There there was a stop cock and it went into copper pipe and onto the
copper a large sleeved earth wire was connected with a tag on saying
"Do Not Remove".

The steel pipe was leaking so I have taken it all out and replaced
with blue plastic pipe. Was looking at the earth arrangement and
wondering if I need to earth the wiring in another way, into the
ground or something, or are we still earthed through the water in the
plastic pipe out to the outside world?

TW

This is the supply in the porch:
https://photos.app.goo.gl/ZhguWVyk5kZkbs1X9
Two substantial earth cables from the black box, one going to the box of
trip switches, the other just dangling, redundant from the old economy 7
circuit or something.

Can wiser eyes than mine declare the type of earthing arrangement?

That superficially at least looks like a TN-C-S install. There is a
yellow sticker on the side of the cutout, does that say PME by any chance?

If it is as it appears, then the connection to the water main was just
an equipotential bond. It still needs to be connected back to the
incoming cold supply just after your stop tap if your internal pipework
is metal, but it does not pose as serious a risk as not having a main
earth.



--
Cheers,

John.

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