Bob Engelhardt wrote:

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I have a Ward-Leonard variac that was originally used, I think, for
theatrical lighting. It is labeled "20A resistive, 14A otherwise".

I suppose "otherwise" means motors, but motors aren't usually run off
variacs. What else could "otherwise" be?

Also, why only 14A?


** The variac itself has no concern about the load other than the RMS current value. Cos that is what heats the windings.

Is there a switch on the unit ?

That part may be rated at 14A inductive due to potential arcing at switch off.


..... Phil