Re: A Couple of Questions (voltage reversal)

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Original poster: MrDirect-at-aol-dot-com 

Perhaps a cap has resonance like a transformer ?






I believe (but am not sure) that the impact of voltage reversal is the
mechanical stress on the dielectric.  As Terry mentioned, some dielectrics
tend to "take a set" or remain polarized, with various relaxation times
(why you should leave a short across the cap after discharging it). 
Imagine that you charge a cap up with one polarity... Now discharge it and
then remove the load(or short).. the cap will rebound to some voltage. 
Either due to polarization of the dielectric, or actually some mechanical
shift in the positions of everything.  If you charge it with the opposite
polarity, you are actually working against more than just the no-charge
situation..

Any good explanations?

It does have a significant effect on life (although not as big as
voltage... which is a mechanical stress issue)