長壽命電解電容的(de)用(yong)途(tu)非常廣泛,一般可用(yong)于電(dian)(dian)動(dong)機啟(qi)動(dong)、鎮流器、變頻(pin)器等。電(dian)(dian)解電(dian)(dian)容常見的(de)故障有(you),容量減少,容量消失、擊穿(chuan)短(duan)路(lu)及(ji)漏電(dian)(dian),其中(zhong)容量變化是因電(dian)(dian)解電(dian)(dian)容在(zai)使用(yong)或放置過(guo)程中(zhong)其內(nei)部的(de)電(dian)(dian)解液逐漸(jian)干涸引(yin)(yin)起(qi),而(er)擊穿(chuan)與漏電(dian)(dian)一般為所加的(de)電(dian)(dian)壓過(guo)高或本身質(zhi)量不佳引(yin)(yin)起(qi)。
判斷電(dian)源長壽命電(dian)解電(dian)容(rong)的(de)(de)好壞一(yi)般(ban)采(cai)用(yong)萬用(yong)表(biao)(biao)的(de)(de)電(dian)阻檔進(jin)行測(ce)量。具體方法為:將電(dian)容(rong)兩管腳短(duan)路進(jin)行放(fang)電(dian),用(yong)萬用(yong)表(biao)(biao)的(de)(de)黑(hei)表(biao)(biao)筆接電(dian)解電(dian)容(rong)的(de)(de)正極。紅表(biao)(biao)筆接負(fu)極(對(dui)指(zhi)針(zhen)(zhen)式萬用(yong)表(biao)(biao),用(yong)數字式萬用(yong)表(biao)(biao)測(ce)量時表(biao)(biao)筆互(hu)調),正常(chang)時表(biao)(biao)針(zhen)(zhen)應先向(xiang)電(dian)阻小的(de)(de)方向(xiang)擺(bai)動(dong),然后逐漸返回直至無窮大處(chu)。
表針的擺動幅度(du)越大或(huo)返回(hui)的速度(du)越慢(man),說明(ming)電容(rong)(rong)的容(rong)(rong)量越大,反之則(ze)說明(ming)電容(rong)(rong)的容(rong)(rong)量越小(xiao)。如表針指在中間某處不再(zai)變化,說明(ming)此(ci)電容(rong)(rong)漏電,如電阻指示值很小(xiao)或(huo)為零(ling),則(ze)表明(ming)此(ci)電容(rong)(rong)已擊(ji)穿短路。
因萬用表使用的電(dian)池電(dian)壓(ya)(ya)一般很低,所以在測(ce)量低耐壓(ya)(ya)的電(dian)容(rong)時(shi)(shi)比較(jiao)準(zhun)確,而(er)當電(dian)容(rong)的耐壓(ya)(ya)較(jiao)高時(shi)(shi),打(da)時(shi)(shi)盡管測(ce)量正常,但加上高壓(ya)(ya)時(shi)(shi)則有可能發生漏電(dian)或擊穿現象。