我国现采用的J型供电系统中的可控硅配电箱过压保护装置,存在着较严重的过敏性误动作现象,给乘务员的检修工作带来的困难是不可忽视的。过敏性误动作现象的出现,经常迫使检修技术不够熟练的乘务员停止发电机工作,从而影响整列客车供电系统的正常工作。在我们检修过程中经常发现各用电设备的突然开闭和外来较强干扰信号, China is now using J-type power supply system SCR distribution box overvoltage protection device, there is more serious allergic malfunction, to the flight attendant overhaul difficulties can not be ignored. The appearance of allergic misoperation often forced the flight attendant who lacked the maintenance skills to stop the work of the generator, thus affecting the normal work of the entire train power supply system. In our overhaul process often found that the sudden opening and closing of the electrical equipment and strong external interference signal,