# Re: 220 volt variac

terryS wrote:
On Jul 11, 10:18 pm, Fred Cameron <fmaxsc*nosp...@xxxxxxxxxxxxx>
wrote:
I am looking for a 220 volt variac.

Does anyone have such a beast?

Thanks!

Fred
WA4PAV

On the basis that a transformer, In this case a variable tap auto-
transformer, is an electromagnetic device:
Question: Could one not input the variac with say 230 volts instead of
115 volts.
Then at, say, 20% dial setting the output would be 46 volts and at
100% it would be 230 volts. Etc.
As long as the current and total power transformed are within the
ratings of the variac, would it matter?
After all transformers, either those with separate input and output
windings, tapped or untapped, or auto-transformers can be used to step
voltage up/down and so forth.

One could if the 120V variac was seriously over built. The problem is
if the variac was built using normal engineering practices, the turns
ratio would drive the core partially, or fully into saturation at 240V,
and it would at the minimum get very hot, and at the worse case, blow
the breakers.

-Chuck
.

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