On Tue, 19 Jun 2018 08:59:19 +0100, Tim Lamb
wrote:

In message , Archibald
Tarquin Blenkinsopp writes
On Sat, 12 May 2018 12:59:25 +0100, ARW
wrote:
Yes.

One thing that is annoying about SWA cables is that it only semes to be
available as 3 phase, not in single phase plus earth! So I'm forced to
put sticky coloured tape on the conductors at both ends of the SWA!

It's not that big a deal:-)

It was on a site I went to at Cambridge. The 110V shower was supplied
from SWA with a green sheath on the [grey] CT of the transformer, the
other green sheath at the shower end was placed on a [black] 110V feed
and connected to ground of course.

It was on that site that I heard one of the most profound, logical
observations that I have ever come across.

The site Electrician explained that the transformer had "lost it's
smoke"

He had seen electrical items lose their smoke before, it seems the
only way to get the things working again, is to collect all the smoke
that was lost, and put it back.

He persuaded me that there was little point finding all that missing
smoke, so I snipped the cable ends and saw to it that another
transformer was supplied.

I wonder if we will go back to RYB ?

At least the consensus on what core to use as ground was fairly
universal.

Is there an established phase rotation with grey/brown/black as there
was with RYB?

I've been re-using salvaged 4mm singles now connected to a pre-change
supply. Curiously only 1 out of 4 machines rotated correctly.

For obvious reasons, I don't bother with the National Lottery:-)

There is indeed, there seems no strict convention as to whether the
black or grey becomes ground in single phase applications though.

On the plus side, I have never seen the brown with a green tracer on
it. :-)

AB