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Equalizing resistors for electrolytic capacitors



Original poster: "Hydrogen18" <hydrogen18@xxxxxxxxxxxxx>

List,

I have a large number of small electrolytic capacitors I am trying to connect in series. Since they have the nominal -10% to +85% value control on them the potential exists for a unequal division of voltages. I understand than resistors across each capacitor can help solve this problem, but have found no formulas or examples on what values should be used. Is it an arbitrary thing? Any help you could provide would be greatly appreciated.

So far I have come up with:

 I understand the time constant of Tau(R*C) correctly it would be:

47000 * (330*(10^-6) = 15.51 seconds.

so in about a 78(5 Time constants = 98% charge gone) seconds provided my caps are at full voltage they will only be at 2 volts each with a 47k resistor across each one.This is still a high voltage when you factor them being in series. Although at that low of voltage I should be able to short them and they wont have energy to internally damage themselves I think.
This is for a DC tesla coil filter cap
---Eric