工頻耐壓試驗是變壓器試驗的關鍵項目，是考核主絕緣抗電強度的基本措施。對變壓器繞組連同套管一起進行超過額定電壓一定倍數的工頻交流試驗電壓，持續時間lmin的交流耐壓試驗。其目的是用比運行情況更為嚴酷的條件下檢驗變壓器繞組的絕緣水平。
 
交流耐壓試驗屬于破壞性試驗，因此，必須在其他絕緣試驗都合格的基礎上進行，以免造成不必要的絕緣擊穿與損壞事故。
 
變壓器繞組絕緣經過交流耐壓試驗合格后，就可以投入運行。
 
工(gong)頻耐(nai)壓(ya)試(shi)(shi)驗(yan)(yan)(yan)裝置(zhi)是由試(shi)(shi)驗(yan)(yan)(yan)變(bian)壓(ya)器(qi)和(he)耐(nai)壓(ya)試(shi)(shi)驗(yan)(yan)(yan)操(cao)作臺組成，可用于(yu)變(bian)壓(ya)器(qi)耐(nai)壓(ya)測(ce)試(shi)(shi)，電(dian)(dian)(dian)(dian)纜耐(nai)壓(ya)試(shi)(shi)驗(yan)(yan)(yan)等各種電(dian)(dian)(dian)(dian)氣設備的(de)耐(nai)壓(ya)絕(jue)緣(yuan)試(shi)(shi)驗(yan)(yan)(yan)。工(gong)頻耐(nai)壓(ya)試(shi)(shi)驗(yan)(yan)(yan)裝置(zhi)是根據電(dian)(dian)(dian)(dian)力行(xing)業(ye)標準設計(ji)的(de)智能耐(nai)壓(ya)試(shi)(shi)驗(yan)(yan)(yan)設備，用于(yu)對各種電(dian)(dian)(dian)(dian)器(qi)產品、電(dian)(dian)(dian)(dian)氣元(yuan)件(jian)、絕(jue)緣(yuan)材料等進行(xing)規定電(dian)(dian)(dian)(dian)壓(ya)下的(de)絕(jue)緣(yuan)強度試(shi)(shi)驗(yan)(yan)(yan)，以考核(he)產品的(de)絕(jue)緣(yuan)水平，發現被試(shi)(shi)品的(de)絕(jue)緣(yuan)缺(que)陷，衡量過電(dian)(dian)(dian)(dian)壓(ya)的(de)能力。廣泛應用于(yu)電(dian)(dian)(dian)(dian)工(gong)制造部門、電(dian)(dian)(dian)(dian)力運行(xing)部門、科研單位和(he)高(gao)等院校。