電解電容幾乎是所有開關電源必用元件之一，位置相當醒目，在電路的高壓側，作用巨大，它決定著電源的純凈程度，并且也算易損元件，電解電容廠家就結合實際談談電解電容的一些特性和在維修更換中的注意事項。

　　Electrolytic capacitor is almost one of the necessary components of all switching power supply. Its position is quite eye-catching. It plays a huge role in the high-voltage side of the circuit. It determines the purity of the power supply and is also a vulnerable component. The manufacturer of electrolytic capacitor will talk about some characteristics of electrolytic capacitor and the matters needing attention in maintenance and replacement.

　　電解電容在開關電源中主要是起到濾波作用，主要用來凈化電路，很多開關電源從整流橋出來的直流電之間就并聯兩個串聯的電容，以此點切入展開講解一下。

　　Electrolytic capacitor in the switching power supply mainly plays a filtering role, mainly used to purify the circuit, many switching power supplies from the rectifier bridge out of the DC between two series capacitors, starting from this point to start to explain.

　　第一，電解電容是并聯在直流電路中濾波，體現它的通交流而隔直流特性，如果不阻隔直流電路就大短路了直接爆了，通交流隔直流其實也是所有電容的共性，這里就不詳談了。

　　First, the electrolytic capacitor is parallel connected in the DC circuit to filter, reflecting its AC and DC isolation characteristics. If the DC circuit is not blocked, there will be a large short circuit, and it will explode directly. In fact, it is common for all capacitors to connect AC and DC, so I will not discuss it in detail.

　　第二，因為電解電容用在開關電源整流橋后邊，是脈動直流電路，頻率非常低，并不是高頻場合，說明電解電容是用低頻場合，如果常接觸電路就會知道，電解電容不會被用到高頻電路中，這也是它的應用局限性。

　　Second, because the electrolytic capacitor is used behind the rectifier bridge of switching power supply, it is a pulsating DC circuit with a very low frequency, not a high-frequency occasion. It shows that the electrolytic capacitor is used in low-frequency occasions. If you often contact the circuit, you will know that the electrolytic capacitor will not be used in the high-frequency circuit, which is also its application limitation.

　　第三，兩個電容是串聯后并聯在整流橋后面的，整流橋整流后出來的應該是310伏左右的直流電，而圖上所串聯起來的兩個電容額定電壓是200伏，說明一個問題，電容器串聯可以和電阻一樣分配電壓，但是，電容器的容量是越串越小，意思就是兩個容量220uF的電容串起來后使用，它的容量相當于110uF，反之亦然，電容器越并容量越大。

　　Third, the two capacitors are connected in series and connected in parallel behind the rectifier bridge. The output of the rectifier bridge after rectification should be about 310 V DC, while the rated voltage of the two capacitors connected in series in the diagram is 200 V, which indicates that a problem is that the series capacitor can share the same distribution voltage as the resistance. However, the capacity of the capacitor is the smaller the series, which means that two capacitor strings with 220uF capacity can be connected in series After use, its capacity is equivalent to 110uf, and vice versa. The more the capacitor is combined, the greater the capacity is.

　　第四，從開關電源上的兩電容先串聯再并聯方式可以做作更深度理解，整流塊整流后電源有正負之分，用在它后邊的電解電容也有正負之分，既然這里有正負之分，電解電容就不能用錯或接反，否則，接反通電后直接會爆炸，非常危險。

　　Fourth, the two capacitors on the switching power supply are connected in series and then connected in parallel. The power supply after rectification of the rectifier block is divided into positive and negative, and the electrolytic capacitor used behind it is also positive and negative. Since there are positive and negative points here, the electrolytic capacitor can not be used wrongly or reversely. Otherwise, it will explode directly after being connected reversely, which is very dangerous.

　　第五，如果維修開關電源需更換電解電容時，在焊接過程中，除了注意極性不能弄反外，還要快速，因為電解電容內部含有電解質，不要讓烙鐵高溫破壞了封口的密封性，造成使用中漏液，影響性能和壽命。

　　Fifthly, if it is necessary to replace the electrolytic capacitor during the maintenance of the switching power supply, in addition to paying attention to the polarity can not be reversed, but also need to be fast, because the electrolytic capacitor contains electrolyte, do not let the high temperature of the soldering iron damage the sealing of the seal, resulting in leakage in use, affecting performance and life.