The life of an electrolytic capacitor is related to the working environment of the capacitor. If a capacitor is -40 to 105 degrees and 5000 hours, the so-called 5000 hours means that the life is 5000H in a working environment of 105 degrees. The life of the working environment is doubled every 10 degrees. vice versa.
If the ambient temperature is too high and exceeds the highest rated temperature of the electrolytic capacitor, the electrolyte will boil over the electrolytic capacitor to generate an overpressure, which will cause the electrolyte to leak due to the irreversible pressure relief action of the pressure relief component, causing permanent damage to the electrolytic capacitor. Therefore, the storage and use temperature of the electrolytic capacitor must never exceed the rated temperature.
In environments with high operating temperatures, capacitors are prone to leakage and accelerate aging. Therefore, in the design and installation, as far as possible, use a capacitor with a small temperature coefficient, and keep away from the heat source and improve the ventilation inside the machine. If necessary, it should be forced to air-cool. In cold conditions, due to the low temperature, ordinary electrolytic capacitors will fail due to the freezing of the electrolyte, which will make the equipment work abnormally. Therefore, it is necessary to use a cold-resistant electrolytic capacitor.
Factors affecting the life of electrolytic capacitors:
The service life of electrolytic capacitors is not only related to the temperature of the ambient temperature, but also related to the magnitude of the ripple current.
Since thermal stress has a decisive influence on the service life of electrolytic capacitors, the heat loss caused by ripple current is an important factor affecting the service life of electrolytic capacitors.
Ripple current refers to the AC component current flowing through the electrolytic capacitor. It is affected by the ambient temperature and the AC frequency. The ambient temperature is different and the maximum allowable value of the ripple current is different. When the ambient temperature is constant, the larger the ripple current flowing in the allowable range, the shorter the service life of the electrolytic capacitor.