On 14/02/2020 13:53, TimW wrote:
On 14/02/2020 13:25, Robin 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?



That looks promising (but also a bit of a dog's breakfast).Â* But I'd
rather leave it to those who have seen an awful lot more of them to
advise the next step.

On a point of detail, can you see/work out where the wire connected to
the copper pipe comes from?

No, it comes from the gaps between the joists.
tw

Don't worry about that, it's trivial compared with your earthing.

The news that you have an overhead supply combined with the "dog's
breakfast" aspect makes me more inclined to suspect a "DIY PME"
installation. That is, someone has come along and connected the earth
cable between the incomer and the consumer unit to make it look as if
you have TN-C-S/PME when in fact you have TT.

It doesn't follow that you have an exceedingly dangerous setup. And
there might be an earth rod somewhere. But when looked at alongside the
consumer unit (with it's mix of brands and lack of RCD protection on
some circuits) I'd be bothered. I think you should have it looked at.
But others will know more and better than me.

In the meantime be careful.



--
Robin
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