Colin Bignell wrote;

SNIP
I'm guessing, but are industrial units wired up with some 230v
sockets running from each of the three phases? Is this to spread
the load out? Seems logical to me if some sockets are fine & others not.
Is every
third socket from phase A, every forth socket from B etc?

Maybe, maybe not. It was always considered good practice to keep at
least 6 feet between sockets on different phases. If they are closer,
they are likely to be wired in blocks, with several adjacent sockets
on one phase. If they are widely spaced, they might be wired on
alternate phases. Again, good practice would be to mark phase
colours, either with phase disks by the socket or by sleeving the
live with a phase colour.

Thanks for that Colin, makes sense.

This is an industrial estate built in the late 1960's. I guess the sockets
are 8 to 10' apart, alas no markings on the two I looked at.

Looks like they could be wired alternately.


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Dave - The Medway Handyman
www.medwayhandyman.co.uk
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