In article ,
Harry Bloomfield writes:

I would though like to know what method they use to reducing the
voltage, That toroid doesn't look capable of delivering more than about
300w.

If it's an auto-transformer, then for a 30V buck, it will
handle a load of about 8 times its VA rating, but that's
still not much (say, 2,500VA). What it could do is reduce
the buck voltage as the load increases above 2,500VA, e.g.
to 10V max at 7,500VA, but that would somewhat mitigate
the object of having the device.

No idea if this is what it actually does.

--
Andrew Gabriel
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