In article ,
Dave Plowman (News) wrote:
In article ,
wrote:
Had a proper look at the earthing on the new place today. The supply
earth is provided by a clamp onto the sheath. It's not, so far as I
can, a tightenable clamp.


That sounds like what existed here on an old installation. Where the
incoming lead water main and the sheath to the mains riser provided the
rudimentary earth.

If you can use the mains riser for earth it needs the correct clamp - but
that's really a job for the supply company to make sure it is up to it.

The electrical installaton here, probably 1920s, got its earth from the
incoming cable sheath. However, after a few days of being fed from a
generator, tests on reconnection showed an inadequate earth from that cable
sheath. The supply company changed things to PME.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle