1 故障现象 某单位一台链条自动焊接机,其工作原理跟一般常用的单相380V调功器相似、由控制器产生触发信号,去控制功率单元可控硅的耐导通角,最终达到控制链环的焊接温度.此机床在半年前开始出现焊接温度不稳的故障现象.其间曾多次检修过,均未找出故障原因. 1 Symptom A unit of a chain of automatic welding machine, its working principle with the commonly used single-phase 380V power regulator similar to the trigger signal generated by the controller to control the resistance of the power unit SCR conduction angle, and ultimately to control Chain welding temperature. This machine began six months ago, the instability of the welding temperature failure phenomenon. During which many times overhaul, did not find the cause of the malfunction.