地下電纜故障定位儀器對地下電纜檢測

　　地(di)下電(dian)纜故(gu)(gu)障(zhang)點(dian)定(ding)(ding)位儀器，可以(yi)準確定(ding)(ding)位地(di)下敷設電(dian)纜的短路故(gu)(gu)障(zhang)點(dian)，工作(zuo)原(yuan)理是通過(guo)在故(gu)(gu)障(zhang)電(dian)纜施加高電(dian)壓，在短路故(gu)(gu)障(zhang)點(dian)會(hui)產生(sheng)高壓放電(dian)，在地(di)面通過(guo)偵(zhen)測(ce)設備準確定(ding)(ding)位。對快(kuai)速查找(zhao)故(gu)(gu)障(zhang)點(dian)提(ti)供了很大幫助。

　　電(dian)(dian)(dian)纜故(gu)(gu)(gu)障(zhang)(zhang)定位(wei)(wei)(wei)儀(yi)是(shi)(shi)對電(dian)(dian)(dian)纜故(gu)(gu)(gu)障(zhang)(zhang)進行定位(wei)(wei)(wei)的(de)(de)(de)測試(shi)的(de)(de)(de)試(shi)驗(yan)儀(yi)器，電(dian)(dian)(dian)纜故(gu)(gu)(gu)障(zhang)(zhang)定位(wei)(wei)(wei)儀(yi)能對電(dian)(dian)(dian)纜的(de)(de)(de)高(gao)阻(zu)閃絡故(gu)(gu)(gu)障(zhang)(zhang)，高(gao)低阻(zu)性的(de)(de)(de)接地(di)，短(duan)路和(he)電(dian)(dian)(dian)纜的(de)(de)(de)斷線，接觸不良等(deng)故(gu)(gu)(gu)障(zhang)(zhang)進行測試(shi)，電(dian)(dian)(dian)纜故(gu)(gu)(gu)障(zhang)(zhang)定位(wei)(wei)(wei)儀(yi)配(pei)備聲測法定點儀(yi)，可以(yi)用(yong)來準確測定故(gu)(gu)(gu)障(zhang)(zhang)點的(de)(de)(de)準確位(wei)(wei)(wei)置，適用(yong)于測試(shi)各種型(xing)號、不同等(deng)級電(dian)(dian)(dian)壓的(de)(de)(de)電(dian)(dian)(dian)力電(dian)(dian)(dian)纜及通信電(dian)(dian)(dian)纜，電(dian)(dian)(dian)纜故(gu)(gu)(gu)障(zhang)(zhang)定位(wei)(wei)(wei)儀(yi)的(de)(de)(de)試(shi)驗(yan)原(yuan)理(li)是(shi)(shi)通過發射(she)脈沖和(he)反射(she)脈沖之間的(de)(de)(de)距(ju)離，電(dian)(dian)(dian)纜故(gu)(gu)(gu)障(zhang)(zhang)定位(wei)(wei)(wei)儀(yi)實現定位(wei)(wei)(wei)的(de)(de)(de)主要(yao)原(yuan)理(li)是(shi)(shi)跨步電(dian)(dian)(dian)壓定點法。

　　電纜故(gu)障(zhang)定(ding)(ding)位(wei)儀跨步電壓(ya)定(ding)(ding)點法：給(gei)被測電纜施加(jia)脈(mo)動或(huo)脈(mo)沖(chong)信號，如果電纜故(gu)障(zhang)點處存在(zai)破損(sun)并接大地，在(zai)故(gu)障(zhang)點附近就(jiu)存在(zai)跨步電壓(ya)現象，故(gu)障(zhang)點前、后電壓(ya)方向(xiang)互反。

　　電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)定(ding)位(wei)儀(yi)(yi)測(ce)(ce)試(shi)(shi)原(yuan)理：電(dian)(dian)(dian)(dian)(dian)力電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)測(ce)(ce)試(shi)(shi)儀(yi)(yi)由電(dian)(dian)(dian)(dian)(dian)力電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)測(ce)(ce)試(shi)(shi)儀(yi)(yi)主(zhu)機(ji)、電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)定(ding)位(wei)儀(yi)(yi)、電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)路徑(jing)儀(yi)(yi)三個(ge)主(zhu)要部分組成。電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)測(ce)(ce)試(shi)(shi)儀(yi)(yi)主(zhu)機(ji)用(yong)于測(ce)(ce)量電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)性質，全長及電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)點距(ju)測(ce)(ce)試(shi)(shi)端的(de)(de)大(da)致(zhi)(zhi)位(wei)置(zhi)(zhi)。電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)定(ding)點儀(yi)(yi)是在電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)測(ce)(ce)試(shi)(shi)儀(yi)(yi)主(zhu)機(ji)確定(ding)電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)點的(de)(de)大(da)致(zhi)(zhi)位(wei)置(zhi)(zhi)的(de)(de)基(ji)礎上來確定(ding)電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)點的(de)(de)準確位(wei)置(zhi)(zhi)。對(dui)于未知走(zou)向(xiang)(xiang)的(de)(de)埋(mai)地(di)電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)，需(xu)使用(yong)路徑(jing)儀(yi)(yi)來確定(ding)電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)的(de)(de)地(di)下走(zou)向(xiang)(xiang)。電(dian)(dian)(dian)(dian)(dian)力電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)進(jin)行測(ce)(ce)試(shi)(shi)的(de)(de)基(ji)本方法(fa)是通(tong)過對(dui)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)力電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)施加高(gao)壓脈沖，在電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)點處產生(sheng)擊穿，電(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(zhang)擊穿點放電(dian)(dian)(dian)(dian)(dian)的(de)(de)同時對(dui)外(wai)產生(sheng)電(dian)(dian)(dian)(dian)(dian)磁波并同時發(fa)出聲音(yin)。

　　首先通過兆歐表判斷出哪幾相電纜存在短路故障，將高壓發生器放電端口通過放電夾鉗接入。將放電夾鉗接入故障電纜，另一頭接高壓電容。

合(he)上開關，啟動設備，將轉換開關打到連續放電(dian)。緩(huan)慢加大放電(dian)電(dian)壓。

　　有時放(fang)(fang)電充分直接就可以(yi)聽到(dao)(dao)“啪啪”的(de)放(fang)(fang)電聲，在故障點(dian)處能(neng)明顯感覺到(dao)(dao)地面的(de)震動。找到(dao)(dao)故障點(dian)后，開挖修復。