12 Jun
2009
12 Jun
'09
6:52 p.m.
The other thing that changes with f is the inductive
impedance of all the
(other) windings of the transformer. Ferro-resonance transformers do not rely
only on the resonance principle, magnetic/inductive issues are also very
involved. I'm not at all convinced that simply changing the C is adapting the
supply for the new frequency (50 Hz). That you are having to go so far off the
theoretical new C would tend to support this.
Possibly. However, I have a ferroresonant supply (for a pair of Diablo
Model 30 hard disks) which has tappings on the 'resonant' winding for 50
or 60 Hz operation. There's a table inside saying how to strap it for
different input voltages and t h2 frequencies. The capacitor, IIRC is not
changed, just the tappings.
This would seem to indicate it's possible to design a ferroresonant
transformer with the 'main' windings are OK for either frequency. Of
course this doesn't mean all such transformers are designed that way.
And as others have pointed out, changing the value of the capacitor is
not quite the same thing ans changing the tappiongs on the inductor.
-tony