Datasheet

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Fort Lauderdale, FL 33301 USA • 954-766-2800 • www.kemet.com
6
Snap-In Aluminum Electrolytic Capacitors – ALA7D, +85°C
Shelf Life
The capacitance, ESR and impedance of a capacitor will not change signicantly after extended storage periods, however,
the leakage current will very slowly increase. KEMET products are particularly stable and allow a shelf life in excess of three
years at 40°C. See sectional specication under each product for specic data.
Re-age (Reforming) Procedure
Apply the rated voltage to the capacitor at room temperature for a period of one hour, or until the leakage current has fallen
to a steady value below the specied limit. During re-aging, a maximum charging current of twice the specied leakage
current or 5 mA (whichever is greater) is suggested.
Reliability
The reliability of a component can be dened as the probability that it will perform satisfactorily under a given set of
conditions for a given length of time.
In practice, it is impossible to predict with absolute certainty how any individual component will perform. Therefore, we
must utilize probability theory. It is also necessary to clearly dene the level of stress involved (e.g., operating voltage, ripple
current, temperature and time.) Finally, the meaning of satisfactory performance must be dened by specifying a set of
conditions, which determine the end of life of the component.
KEMET provides an online life calculator that can be used to predict hours of life for a given part number in specic
application conditions. This can be found at: https://elc.kemet.com.
End of Life Denition
Catastrophic failure: short circuit, open circuit or safety vent operation
Parametric Failure:
• Change in capacitance > ±15%
• Leakage current > specied limit
• ESR > 3 x initial ESR value