用低(di)頻探(tan)測(ce)(ce)原(yuan)(yuan)理(li)檢(jian)測(ce)(ce)接(jie)地故障(zhang)是這些年來采用的(de)(de)一種(zhong)新方法，但它所能(neng)檢(jian)測(ce)(ce)的(de)(de)接(jie)地電(dian)阻受直流(liu)系(xi)統對地分布電(dian)容的(de)(de)制約，而且低(di)頻交(jiao)(jiao)流(liu)信號(hao)容易受外界(jie)的(de)(de)干擾，醫(yi)用絕(jue)緣(yuan)檢(jian)測(ce)(ce)儀(yi)，另外注入的(de)(de)低(di)頻交(jiao)(jiao)流(liu)信號(hao)增大直流(liu)系(xi)統的(de)(de)電(dian)壓紋波(bo)系(xi)數。可見，電(dian)橋平衡(heng)原(yuan)(yuan)理(li)和低(di)頻探(tan)測(ce)(ce)原(yuan)(yuan)理(li)均存在若干難(nan)以(yi)克服的(de)(de)缺陷。本文提出一種(zhong)新的(de)(de)檢(jian)測(ce)(ce)方法，即(ji)主回路用不平衡(heng)電(dian)橋檢(jian)測(ce)(ce)總的(de)(de)絕(jue)緣(yuan)電(dian)阻，

絕(jue)(jue)緣(yuan)(yuan)監(jian)(jian)控(kong)儀(yi)(yi)(yi)注意(yi)事項：絕(jue)(jue)緣(yuan)(yuan)監(jian)(jian)控(kong)儀(yi)(yi)(yi)有其電(dian)(dian)網(wang)電(dian)(dian)壓(ya)應用(yong)范(fan)圍(wei)，當電(dian)(dian)網(wang)電(dian)(dian)壓(ya)超過絕(jue)(jue)緣(yuan)(yuan)監(jian)(jian)控(kong)儀(yi)(yi)(yi)應用(yong)范(fan)圍(wei)時，如(ru)若發生接地(di)故障，電(dian)(dian)網(wang)電(dian)(dian)壓(ya)會(hui)(hui)加載(zai)在絕(jue)(jue)緣(yuan)(yuan)監(jian)(jian)控(kong)儀(yi)(yi)(yi)兩端，會(hui)(hui)擊穿絕(jue)(jue)緣(yuan)(yuan)監(jian)(jian)控(kong)儀(yi)(yi)(yi)，因此要(yao)注意(yi)絕(jue)(jue)緣(yuan)(yuan)監(jian)(jian)控(kong)儀(yi)(yi)(yi)的應用(yong)電(dian)(dian)壓(ya)范(fan)圍(wei)。絕(jue)(jue)緣(yuan)(yuan)監(jian)(jian)測儀(yi)(yi)(yi)報(bao)警設置值不可設置太(tai)大也不可太(tai)小(xiao)，推薦按照50歐姆(mu)/伏設定報(bao)警值。不同工況絕(jue)(jue)緣(yuan)(yuan)水平(ping)不同，如(ru)果(guo)報(bao)警值設定太(tai)高，絕(jue)(jue)緣(yuan)(yuan)監(jian)(jian)控(kong)儀(yi)(yi)(yi)會(hui)(hui)頻繁報(bao)警，設定太(tai)低(di)則(ze)安(an)全系統不夠。

絕(jue)緣(yuan)監(jian)視儀(yi)注(zhu)意事項：絕(jue)緣(yuan)監(jian)控(kong)儀(yi)可(ke)以認為(wei)是(shi)監(jian)測(ce)兩個一點都(dou)不(bu)相(xiang)關聯物(wu)體之間絕(jue)緣(yuan)電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)值，如果在(zai)TN-S等(deng)接地電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)中電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)對地絕(jue)緣(yuan)電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)為(wei)0，測(ce)量絕(jue)緣(yuan)電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)毫無意義，絕(jue)緣(yuan)監(jian)測(ce)儀(yi)報警。當然在(zai)TN-s系統中做電(dian)(dian)(dian)(dian)(dian)機離線監(jian)測(ce)是(shi)可(ke)以，因為(wei)電(dian)(dian)(dian)(dian)(dian)機繞組(zu)與地絕(jue)緣(yuan)，絕(jue)緣(yuan)監(jian)控(kong)儀(yi)可(ke)以正常使用。被(bei)監(jian)視電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)額定電(dian)(dian)(dian)(dian)(dian)壓(ya)不(bu)可(ke)超過絕(jue)緣(yuan)監(jian)控(kong)儀(yi)使用電(dian)(dian)(dian)(dian)(dian)壓(ya)范圍。