DoN. Nichols wrote:
According to Ted Samuels :
Michael A. Terrell wrote:
Ted Samuels wrote:

[ ... ]

Look at the windings. I have seen them so oxidized that the brush
couldn't make contact.

That would have simply made the thing unable to deliver current
to the load -- no chance for that making it pop fuses or circuit
breakers.

I think I figured out the problem. The actual wording on the front of the Variac is
"350 CYCLES Min" I took it to mean "350 CYCLES Minute" but what it probably
means is
350 CYCLES Minimum.

O.K. Then it is most likely a 400 Hz one, which is what I
thought. There, there is not sufficient iron, so 60 Hz saturates it and
draws a ton of current.

In either case it's just not suitable for 60 Hz.

Agreed. Nice to have around aircraft power systems, however.

I bought three of them all ganged on a common shaft in the late 90s .
Took a quick look and assumed I was getting 3, 10 amp Variacs for $8.

A fool and his money are soon parted. In any case I am told that 400Hz
Variacs go for about $10 ea so nothing's lost yet, except my expectations.

T