What about two in series? You could use ordinary caps then. But would need
them twice the value.

In article , íçëéìèî
wrote:
What about two in series? You could use ordinary caps then.

I am not sure about this, so what follows may be wrong. However I doubt it
would be safe to use a pair of normal non-reversable electrolytics, even if
connected in series with opposing polarities. This is because any applied
voltage should be shared equally. Hence when large voltages were applied to
the pair, one would be seeing a large reverse bias.

IIRC with reversables *both* plates are processed to act as insulating
barriers/capacitors on each 'end' of the electrolyte. With non-reversables,
only one plate per cap is processed, so the other plate makes a more Ohmic
contact with the electrolyte.

If using a pair, I think it is desirable to use a pair of shunt resistors
to ensure voltage sharing. Otherwise differences in capacitance and leakage
may lead to one cap having a much higher applied voltage than the other.

Slainte,

Jim

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