没试过，300plc的SFC51支持以下灯，你可以试试
SSL ID INDEX 消息功能
0174H ................读取各个 LED 的状态
................0001H GE，组错误
................ 0004H RUN，RUN LED
................0005H STOP，STOP LED
................0006H FRCE，强制 LED
................000BH BF1 LED
................000CH BF2 LED
................0014H BF3 LED
................0015H MAINT LED
数据记录见 用于S7-300/400 系统和标准函数的系统软件 P734
没法排版真郁闷