On 17/02/2020 20:16, wrote:
On Monday, 17 February 2020 15:07:36 UTC, John Rumm wrote:
On 17/02/2020 12:24, tabbypurr wrote:
On Monday, 17 February 2020 03:26:14 UTC, John Rumm wrote:
On 16/02/2020 18:49, tabbypurr wrote:
On Sunday, 16 February 2020 15:44:19 UTC, John Rumm wrote:
On 15/02/2020 17:54, tabbypurr wrote:
On Saturday, 15 February 2020 09:59:41 UTC, Robin
wrote:
On 15/02/2020 08:35, tabbypurr wrote:
On Friday, 14 February 2020 11:08:57 UTC, Dave
Plowman (News) wrote:
In article , 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?

It was common many many years ago to provide the
earth via the water pipe. Not so today. Get your
leccy board in to sort it out.

It's nothing to do with the leccy board.



Meanwhile what might help Tim is to know that the
relevant function of "Electricity Boards" was
transferred as part of the privatisation of the
industry to distribution network operators (DNOs). As
John has already pointed out they can and do deal with
earthing - although they may charge (and will require
main bonding to be up to current requirements before
they supply PME).

https://www.ukpowernetworks.co.uk/electricity/earthing

The job required is on the OP's installation, not a job
for the DNO on their equipment.

Well its both... You could wire up your installation as if
it were TN-C-S, but that would not be a sensible thing to
do if the DNO had not constructed or upgraded the local
distribution network to support it.

all that's required is to equi bond the water pipe. AFAIK
suppliers don't provide neutral earth terminals on non-PME
supplies.

Yup sorry, I think I misread that last post slightly. Assuming
in the OPs installation its confirmed as the supply being PME,
then indeed all that is required is replacing the missing
bond.

My comment above is the more general version - that if the
supply status is unknown, the enquiry wit the DNO may be the
only *sure* way of establishing if its safe to make use of the
suppliers neutral for the local earth.

(The type of cutout does not tell you much since they often
the same type for all TN supplies - the only difference being
whether the internal link joining N & E is fitted).

There are a lot of noncompliant supply incomers around, but they
were all compliant at time of installation. Eg 30A rated,
touchable live parts, dp fusing, asbestos etc. To the best of my
knowledge it has never been compliant to provide a neutral earth
from a non-PME supply, hence I would not expect to ever see a
non-PME neutral earth connection in this country. If you want to
check with the DNO you can, but is there any realistic basis for
the claimed need to?

Say you wanted to convert from TT to PME. If your cutout
installation predated the network upgrade but was otherwise of an
appropriate type, then you would need to check with the DNO prior
to fitting the missing link (or more likely having them fit it)

Are you saying some sparks were in the habit of fitting a supplier's
neutral to MET link on TT feeds, and using only that for the house's
earth system?

No.

--
Cheers,

John.

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