> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]
> On Behalf Of Ron Youvan
> Sent: Monday, April 23, 2012 11:11 AM
> To: amps
> Subject: Re: [Amps] PIV requirement for identical, individual diodes
>
> Gary K4FMX Schafer wrote:
>
> >> Just draw a diode bridge circuit and you can easily figure out how
> much
> >> voltage is across each diode. Consider that at any given time one
> side
> >> of the transformer is at ground and the other side is connected to
> the
> >> filter capacitor. Then look at what diodes are reversed biased.
>
> > But the filter capacitor is ALWAYS connected across the transformer
> with a
> > full wave bridge. Any spike from the power line will always be shunted
> by
> > the large filter capacitor. No way for a large spike to reverse bias
> any of
> > the diodes.
>
> How about when the capacitor is charged to say, +1,600 Volts and the
> transformer's outingput is
> -1,600 Volts and then an inductive kick causes the transformer outingput
> to jump to 2,000 Volts or more?
> --
> 73 Ron KA4INM -
One side of the transformer is always connected to the filter capacitor and
the other side of the transformer is always connected to ground with two
diodes.
When the polarity of the transformer reverses the opposite side of the
transformer is connected to the filter capacitor and the other to ground.
If a spike of opposite polarity to the ac comes in the other diodes will
conduct just as if ac polarity reversed. The spike will still go to the
capacitor.
73
Gary K4FMX
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