On 14/02/2020 15:59, Andrew wrote:
On 14/02/2020 13:51, TimW wrote:
On 14/02/2020 12:39, Andrew wrote:
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?

RW

Does the black cable that feeds the companies 80 amp fuse come in
from underground ?.

If so, you probably have a PME arrangement. In fact the 10mm earth
cable going into that 80 amp fuse block seems to confirm it.

The CU and meter look reasonably modern (-ish). The ring mains seem
to be protected by a residual current device of some sort. Is RCCB
an older name for RCD ?. Not sure.

Curiously there are Wylex MCBs and an MK one for the immersion.
I didn't think they were physically compatible. Adam will know.


The black cable is the end of the overhead power line, attached to the
corner of the house, coming from a pole across the road.
tw

I wonder why there is an earth cable going into the company fuse
block then ?. I thought overhead supply was phase and neutral only and
you had to have a separate earthing arrangement.

Historically that was the case, but many overhead supplies have been
upgraded with PME capability over the years. (sometimes looking at the
polls will give a clue - they may have earthing conductors running down
the side of every few)

There is another earth cable coming out of the company fuse block
and it droops down but doesn't seem to go anywhere ?. Is this
correct ?.

Probably a left over from the now removed time switched CU.

--
Cheers,

John.

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