Re: Weird safety gap behaviour

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

Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net> 

Hi Ed,

Are you saying the equivalent inductance of the NST is decreasing as the
amplitude is increasing and thus at low voltage (Cp=2.5 Cres), the Fres is
38 Hz and when Lnst decreases, the Fres moves up closer to 60Hz   If so, is
this due to shunts saturating?

Gerry R.
 > Original poster: "Ed Phillips" <evp-at-pacbell-dot-net>
 >
 > Common behavior.  As you raise the primary voltage you reach a point
 > where the core permeability changes enough to cause the charging circuit
 > (leakage inductance and primary capacitor) to become resonant at the
 > power line frequency.  That causes the sudden jump in voltage.  Same
 > thing happens in reverse as you lower the primary voltage.  I once wiped
 > out the multiplier resistor in a multimeter doing the same sort of
 > thing.  In my case the "jump" occurred at only about   25 volts on the
 > primary.
 >
 > Ed
 >
 > Do a search on "ferro resonance" and "parametric oscillations [in L/C
 > circuits]" and you'll probably find out some interesting things.
 >
 >