In article k,
Alistair Riddell wrote:
The same reason as isolation transformers are used for power tools
outdoors. Yes, you can use circuit breakers of various types, but an
isolation transformer can't go wrong.

But if it DOES go wrong... There is potentially 480 volts available if
one side of the floating secondary contacts the live side of of the
mains....

This assumes any such fault to have the secondary winding in phase with
the primary.

And good design of the system as a whole should make this near impossible.

--
*Reality is the illusion that occurs due to the lack of alcohol *

Dave Plowman London SW
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