> I was told that too, but never heard any real proof. The idea was that
> an electrolytic is not a static (pun intended) component. The
> electrolyte is chemically active and will gradually deteriorate if not
> run near it's rated working voltage.
> Possibly just an old wive's tale. If anyone has any authoritative
> source, please post it.
I was taught the applied Voltage developed an insulating layer on one of the
foil surfaces
{similar to anodizing} in contact with the electrolyte, the thickness is
proportional to the
Voltage. (on the surface of the foil with one polarity of applied Voltage)
If the surface is "formed" (or maintained) at a lower Voltage the capacity
will be higher because
the surface coating is thinner.
If a long unused electrolytic capacitor (with a greatly reduced operating
Voltage) is SLOWLY
"re-formed" up to the original operating Voltage the original working Voltage
and capacity will be
restored. (if nothing else is wrong with it)
Chemical impurities will reduce the capacitance and increase the leakage and
series resistance.
Loss of moisture in the electrolyte will reduce the capacitance and how knows
what else.
Reforming long unused electrolytic capacitors with a controllable power
supply with a output
mil-ammeter is probably the best way to do it. (when the current drops to
zero, raise the voltage
slightly)
--
Ron KA4INM - The next election, I know what is going to happen, I'm going
to help.
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