電(dian)纜(lan)電(dian)容對低阻故障定點(dian)的影(ying)響
低阻故(gu)障(zhang)(zhang)在(zai)(zai)用(yong)音頻信(xin)號法尋找電(dian)纜(lan)的故(gu)障(zhang)(zhang)點時因為(wei)電(dian)纜(lan)的芯線之(zhi)間，芯線與鉛皮之(zhi)間都存在(zai)(zai)電(dian)容(rong)(rong)，電(dian)容(rong)(rong)對交(jiao)流(liu)信(xin)號存在(zai)(zai)容(rong)(rong)抗(kang)(kang)，電(dian)纜(lan)越(yue)(yue)長，電(dian)容(rong)(rong)越(yue)(yue)大，容(rong)(rong)抗(kang)(kang)就越(yue)(yue)小，相應地，交(jiao)流(liu)信(xin)號流(liu)過電(dian)容(rong)(rong)的電(dian)流(liu)也(ye)越(yue)(yue)大。所以(yi)，只要(yao)電(dian)纜(lan)的故(gu)障(zhang)(zhang)電(dian)阻不(bu)為(wei)零，則在(zai)(zai)故(gu)障(zhang)(zhang)點之(zhi)后，仍然會(hui)有(you)電(dian)容(rong)(rong)電(dian)流(liu)引(yin)起的磁場(chang)信(xin)號，而且也(ye)有(you)節距(ju)變(bian)化，這就會(hui)造(zao)成故(gu)障(zhang)(zhang)點前(qian)后的信(xin)號強弱變(bian)化不(bu)明(ming)顯(xian)，故(gu)障(zhang)(zhang)點電(dian)阻越(yue)(yue)大，越(yue)(yue)不(bu)明(ming)顯(xian)，測試越(yue)(yue)困難，在(zai)(zai)測試中(zhong)要(yao)注意!
