Matters Needing Attention in Use of Electrolytic Capacitor(I)

1. DC electrolytic capacitors are polar: the polarity of the capacitor is marked on the base of the capacitor so as not to cause circuit short-circuit or capacitor damage due to polarity. Use bipolar electrolytic capacitors when using non-stationary polarity or on uncertain circuits. Note that DC electrolytic capacitors cannot be used in AC.

2. Use voltage not greater than rated voltage: use voltage greater than rated voltage, leakage current will increase, may damage the capacitor. The recommended working voltage is between 70 and 80 of the rated voltage. The use of the capacitor under the recommended working voltage will prolong the life of the capacitor.

3. Do not allow excessive ripple current through the capacitor: the application of ripple current in excess of the rated value will lead to the capacitor body overheating, capacity decline, damage to the life of the capacitor shortened. The peak value of the applied ripple voltage shall be less than the rated operating voltage.

4. The temperature range of working environment is suitable: the characteristic of capacitor varies with the working temperature. In the case of higher temperature, the leakage current increases and the loss decreases; at low temperature, the capacity and leakage current decrease and the loss increases. The use of capacitors at lower temperatures will prolong their life. According to scientific statistics, for every 10 ℃ drop in environmental temperature, its service life is doubled.

Check working frequency: the capacitance of electrolytic capacitors is usually measured at 100~120Hz frequency. However, the capacity will decrease with the increase of the frequency, the loss will increase with the increase of the frequency, and the ambient temperature will increase.