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STORAGE LIFE
During transport or storage, the temperature of electrolytic
capacitors is allowed to fall below their lower category
temperature and reach a minimum of -65 °C, while their
upper category temperature may not be exceeded.
Depending on the design and the purity of the materials
used, electrolytic capacitors offer very good storage
properties. They can be stored in dry rooms at temperature
ranging from -40 °C to +40 °C (preferably between 0 °C and
+25 °C) for up to three years without any restriction. Within
that period it is possible to apply the fully-rated voltage to
the capacitors without any further preparation. This
procedure neither impairs the capacitor’s operational
reliability nor its life expectancy.
All electrolytic capacitors have a leakage current when a
direct current is applied. This leakage current depends on
time, voltage, and temperature. After long dead storage this
leakage current will increase and, for a short time, can be
10 times greater at the time of reuse. The capacitor will not
be damaged and its life expectancy will not be impaired if
the rated voltage is applied directly after long storage. In
general, the expected continuous operating leakage current
will be re-attained or fall below its value after about
30 minutes. Any operation below the rated voltage will result
in a significantly lower leakage current.
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