variac ballasts

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

Original poster: "Oxandale, Terry by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Toxandale-at-SPP-dot-org>

I've tried to follow any strings about the variacs being used as
ballasts, and have a thought I'd like to throw out to you guys. My
interpretation of the data so far is that my 1256's have a core too
small to be used effectively as a ballast (or too few turns?)for a
240vac supply. I only use about 40% of the windings in the single variac
ballast mode. I reasoned that with 2 in parallel, they would work better
because more of the winding would be used on each variac (half the
impeadance so more winding needs to be used, leaving less turns on the
open end), but the improvement was insignificant. It still appears the
cores are saturating. I am currently using a 14.4kv pig set up for
240vac input. If I was to re-wire the pig (parallel the two separate
primary windings) primary for 120vac in, 14.4kv out, then use only
120vac on the ballast variacs, would this not be a "step" in the right
direction toward eliminating my core saturation problem? My thoughts are
that the open end of the variac will see a much lower voltage (closer to
the 280vac specs for the 1256) and thus I may avoid the perceived
problem of turns/volt (is this correct?) for this small cross section of
the variac core. If I am correct in reading these strings that high
voltage is a culprit in saturation for a given size of core, would my
reasoning be flawed here? Thanks.

(Un)Terry