At 07:49 AM 6/27/00 +0100, Steve Thompson wrote:
> >For interest, I modelled some start up conditions on spice. Based on a
> >transformer designed to give 2.5kV .8A dc CCS (effective secondary Rs 40
> >ohms, 30uF smoothing), 40 ohms in the 220V feed for just 3 cycles (50Hz)
> >limits the peak current in the diodes/smoothing cap to under 5A. The
> >repetitive peak current under settled conditions at 650mA dc is 3.3A.
> >
> >Steve
> >
Steve,
My setup is a little more aggressive than that. Transformer secondary is
rated at 2525 VAC @ 1.9 amps. Secondary measured DC resistance is 12 ohms.
Full wave bridge with 32 mfd filter. I figure 0.2 ohms mains source
impedance (+/-). The two series resistors are 5 ohms each with one shorted
out at ~50 mS followed by second one at ~100 mS (235 volt, 60 Hz mains).
If you have the time and interest, I'd sure like to know what Spice says
about that.
Thanks & 73,
Larry - W7IUV
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