"JW"
"Phil Allison"

Is there any reason that a 120VAC to 120VAC isolation transformer would
draw 2.54A on its primary when there is no load present on it's
secondary?


** Is that 2.54 amps RMS or not ?

Yes. I've measured it with the same result using both a Watts Up meter and
a Fluke 87.

** Good.


In any case, is it getting rather hot and making a humming noise ?

Making a humming noise, yes. It's not getting hot, the external
temperature rise of the case is only about 10c.


** Sounds about normal for a large e-core tranny


The actual wattage when the primary is at 120V is only 42W as measured by
the Watt meter.

** That is pretty high actually - a typical 1KVA tranny has about 6 to 8 %
power loss at full load.


Here's why - the power factor is really crappy at just
about .15. This would explain everything.

** Not everything.

You have to know that the current waveform is distorted - THIS fact is
causing the poor PF when unloaded.


.... Phil