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The never ending saga: Ballasting



Hello,

A few days ago I posted questions regarding ballasting and was wondering
why the voltage drop. Tonight I have done some experiments, as empirical
data is needed for someone who barely understands this (ME!). I tried a
inductor in series with my PT, a 60 mA neon primary with secondaries
shorted together. I got almost a 40 volt drop to the PT, I was only getting
100 V into it (0-140 volt variac). Then I tried 16 uF Cap across the mains
right after the inductor (neon primary), and heck if I was getting 135
volts, only dropping 5 volts from the variac supply! Now have I truly
missed the boat? Probably. But why didn't someone just mention that I
needed to place some C across the lines to get back lost voltage? I tried
it again with another inductor and found I could limit current to 15 amps
at 135 volts, with terminals shorted on the PT, and this followed my
calculations including DC resistive losses (as measured). Voltage drop from
impedance is something I don't quite follow. But it does seem that a little
capacitance in the inductive current limiting scheme is called for. I found
no indications of mains resonance, but can anyone explain how/why?

Regards,

David Trimmell