In article ,
Michael A. Terrell wrote:

There are high isolation transformers with the windings on separate
bobbins. The efficiency is lower than traditional overlaid winding, but
the two windings aren't close enough for anything less than a lightning
strike from reaching the secondary and there isn't any design that is
safe from a direct strike.

Indeed. Often called 'medical quality'.

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*I don't work here. I'm a consultant

Dave Plowman London SW
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