This article analyzes the cause of interlock when using MS - 4201 switch I/o plate as control panel to control stepping motors on industrial control ma chine,and gives the solution to the interlock.

• 介绍了在工技机上利用MS-4201开关量输入输出板兼作步进电机控制板控制多台步进电机所产生的互锁，分析了其产生的原因及解决方法。