對于管板焊機的故(gu)障(zhang),必須正確分析(xi),有的故(gu)障(zhang)很容(rong)易(yi)查找,僅換(huan)幾個元件即可排(pai)除。但(dan)由(you)于線(xian)路(lu)設計不(bu)合理產生的誤差,就需(xu)要根據(ju)實(shi)際情況(kuang)分析(xi)處理。例如(ru),我們(men)使(shi)(shi)用(yong)(yong)77—1型焊(han)機(ji)時曾發現(xian),當(dang)工作(zuo)電(dian)(dian)流30A以上(shang)時,焊(han)機(ji)接觸(chu)器CJ2有忽通忽斷的響聲,其后(hou)自動切(qie)斷電(dian)(dian)源;如(ru)無高(gao)(gao)頻電(dian)(dian)流,CJ2又工作(zuo)正常。我們(men)分析(xi)電(dian)(dian)路(lu)圖后(hou)認(ren)為,該焊(han)機(ji)利用(yong)(yong)高(gao)(gao)頻引弧,使(shi)(shi)高(gao)(gao)、低頻處于一個電(dian)(dian)路(lu)上(shang),如(ru)果(guo)高(gao)(gao)頻扼流圈不(bu)能阻止高(gao)(gao)頻電(dian)(dian)流進入低頻電(dian)(dian)路(lu),將使(shi)(shi)工作(zuo)不(bu)正常,甚(shen)至(zhi)燒壞電(dian)(dian)器元件。上(shang)述故(gu)障(zhang)就屬于這(zhe)種情況(kuang),即高(gao)(gao)頻電(dian)(dian)流進入了(le)低頻電(dian)(dian)路(lu)。