In the process of application, electrolytic capacitors are often selected to form capacitor banks in series or in parallel because of insufficient capacitance or voltage withstanding level. Under what circumstances do we need to choose series or parallel connection? Specifically as follows:

I. Series use of electrolytic capacitors

When we need a voltage withstand level of 700V or higher, a single capacitor can not be satisfied. At present, the highest voltage capacitor in China is 700V capacitor, and the price is relatively expensive. Then we can choose two or more 400V capacitors to use in series. When using in series, the capacity of electrolytic capacitor will be met. The voltage withstand value increases with the decrease of pressure.

II. Parallel use of electrolytic capacitors

When we need a large capacity, the single capacitor can not meet our requirements because of the volume limitation. At this time, we can choose multiple capacitors to be connected in parallel to form an electrolytic capacitor group. When used in parallel, the capacity of the electrolytic capacitor will increase, and the withstand voltage level will be inconvenient.

In parallel or series applications, capacitors need to pay attention to the polarity of capacitors. The positive and negative electrodes of electrolytic capacitors should not be reversed. In welding, virtual welding or poor contact should be avoided. If improperly installed, it may lead to insufficient voltage or capacity, resulting in excessive heating of the current of electrolytic capacitors and serious explosion.