Rich says:
>>Now, when two capacitors are placed in series ACROSS DC, let
alone AC, the
> >>voltage divides inversely proportional to the capacitance.
>
>True enough. However, you are trying to fly on an assumption.
Which assumption? Your assumption is that the voltage will divide unequally.
However, if the diodes have equal capacities, then the 250 volts will divide
to give 125 volts across each diode. If the capacitances aren't equal, you
don't know how the volts will divide.
Ian G3SEK says:
> but so long as the diodes are reasonably well matched, eg full-spec
brand-name diodes from the same
>bandolier, we should be pretty safe.
I said
>If you have branded diodes from the same date code, and/or guaranteed
controlled avalanche characteristics,
which is I guess, pretty much the same thing.
Having had 21 years in the semiconductor industry, I'm probably rather more
cynical about it than most people, so I don't place too much trust in non
specified or non guaranteed parameters - and not much trust in guaranteed
ones, either.
Gerald says:
>If one designs a circuit so poorly that the equalized diodes
>do not have a safety factor of at least 4 for just such an occasion
>and did nothing on the mains input to protect from over voltage
>they get to go back to the drawing board and forget about a raise
>that year.
I don't know about a safety factor of 4, but the concept I agree with. But
what's this 'raise' business? Don't see too many of them around!
73
Peter G3RZP
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