中(zhong)小型冷库制冷系统中(zhong)全(quan)封闭压(ya)缩机和冷风(feng)机的(de)风(feng)扇电动机都要使用电容器(qi)。而电容器(qi)的(de)好坏将(jiang)直接影响全(quan)封闭压(ya)缩机和冷风(feng)机的(de)风(feng)扇电动机的(de)工作状(zhuang)态。

判(pan)断电(dian)(dian)容器(qi)(qi)好(hao)坏，可用(yong)指针式万(wan)(wan)用(yong)表(biao)(biao)进(jin)行检测。具体判(pan)断电(dian)(dian)容器(qi)(qi)好(hao)坏的(de)操作(zuo)方法(fa)是:将(jiang)(jiang)电(dian)(dian)容器(qi)(qi)与(yu)全封(feng)闭压缩机和冷风机的(de)风扇电(dian)(dian)动机电(dian)(dian)路(lu)断开(kai)，用(yong)改锥的(de)金属部分(fen)碰(peng)一下电(dian)(dian)容器(qi)(qi)的(de)两个端子，放一下电(dian)(dian)。然后(hou)用(yong)万(wan)(wan)用(yong)表(biao)(biao)RX100或(huo)RX1K挡进(jin)行测量(liang)(liang)。测量(liang)(liang)时，将(jiang)(jiang)两表(biao)(biao)笔分(fen)别接(jie)触电(dian)(dian)容器(qi)(qi)的(de)两极，若(ruo)表(biao)(biao)针先指向低(di)阻(zu)值(zhi)，并逐(zhu)渐退回高阻(zu)值(zhi)，说(shuo)明该(gai)电(dian)(dian)容器(qi)(qi)具有充(chong)放电(dian)(dian)能力，是好(hao)的(de)。若(ruo)表(biao)(biao)针指示在(zai)低(di)阻(zu)值(zhi)而(er)不能退回，说(shuo)明电(dian)(dian)容器(qi)(qi)已短路(lu)。若(ruo)表(biao)(biao)针一开(kai)始(shi)就(jiu)指示在(zai)高阻(zu)值(zhi)或(huo)表(biao)(biao)针根(gen)本就(jiu)不动，说(shuo)明该(gai)电(dian)(dian)容器(qi)(qi)已断路(lu)。

为全封闭压缩机(ji)和冷(leng)风(feng)机(ji)的(de)风(feng)扇电(dian)动(dong)机(ji)选用新电(dian)容(rong)器(qi)时(shi)要注意(yi)其耐压情况。电(dian)容(rong)器(qi)上所(suo)标明(ming)的(de)额(e)定(ding)(ding)电(dian)压是允许使(shi)用电(dian)压，如果将电(dian)容(rong)器(qi)接在超过其标定(ding)(ding)的(de)工作电(dian)压的(de)电(dian)路中，电(dian)容(rong)器(qi)将被击(ji)穿。全封闭压缩机(ji)和冷(leng)风(feng)机(ji)的(de)风(feng)扇电(dian)动(dong)机(ji)有使(shi)用380V和220V电(dian)压的(de)，这一点在维(wei)修(xiu)时(shi)要格外注意(yi)。