In the long-term operation of the power supply, it is possible that the internal potentiometer may become loose or shifted, causing a large change in the output voltage, which is very easy to cause misjudgment or missed judgment. Therefore, in high-demand occasions, the power supply and other equipment will be periodically calibrated to ensure their stability. However, the once-a-year calibration generally cannot find the problem in time. When a large deviation is found in the output of the power supply, the power supply may have been working in this state for several months.

    The output performance of the power supply directly affects the working state of the device under test. If the output performance of the power supply deteriorates, it may cause the working state of the device under test to change, which will affect the accuracy and consistency of the test. From the power point of view, there are a variety of factors that may cause changes in output performance, which may affect test results.

    The life of the power supply mainly depends on the life of the electrolytic capacitor, and when the electrolytic capacitor passes the life guarantee period, it does not immediately fail, but its performance will get worse and worse, resulting in the deterioration of the power output quality of the power supply. After the life of the electrolytic capacitor expires, the user may not be able to immediately notice the power output change, which will affect the test.

    The life of an electrolytic capacitor is mainly related to its operating temperature. When the operating temperature rises by 10°C, the life of the capacitor decreases by half. The long-life electrolytic capacitor programming power supply uses high-temperature and long-life electrolytic capacitors, and through a good circuit design and reasonable layout, the temperature rise of the electrolytic capacitor is reduced as much as possible to ensure a long life.

    It can be seen that even under the worst working conditions specified in the specification (ambient temperature 50℃, full load, 24 hours uninterrupted continuous operation), the life of the electrolytic capacitor can still reach 5.3 years. Depending on the actual working conditions, the life of the electrolytic capacitor of this type of power supply may be as long as 15 years.