Re: Variac in Overdrive

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Adam,

I "think" you will be fine since variacs are pretty well ovedesigned.  If
you can measure the open load current, look for just the variac drawing
higher than normal current on the input side.  Core saturation is the
problem and if that happens the current will be abnormally high.

Cheers,

	Terry


At 03:14 PM 10/25/2001 -0700, you wrote:
>How much can you overvolt a variac? My "small" 120
>volt 17 amp variac doesn't have the taps for 140 out.
>If I set my variac for 120 in and 102.86 out, then
>reverse the leads, I get 120 in and 140 out. This
>results in approximately 16.7% overvolting of the
>windings. Obviously, I then have reduced my variac to
>a step up autotransformer that can't be adjusted on
>the fly.
>
>Can a variac run like this for short (15 to 30
>seconds) runs, or am I putting my variac's windings at
>risk?
>
>thanks
>Adam
>
>=====
>Adam Minchey
>yurtle_t-at-yahoo-dot-com
>www.geocities-dot-com/yurtle_t/index.htm
>
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