S7-200PLC扩展EM231四路模拟量输入模块,EM231电源取自PLC,按S7-200PLC系统手册接入4路4~20mA信号,(短RA及A+,变送器接A+及A-),采集信号子程序如下:TITLE=模拟量采集BEGINNetwork1//初始化,采集输入电流信号LDSM0.0MOVWAIW0,VW40MOVWAIW2,VW50MOVWAIW4,VW60MOVWAIW6,VW70Network2//油温信号校准输出,单位:0.1度LDSM0.0-D6400,VD40*D10,VD40MOVDVD40,VD104/D+256,VD104Network3//低压系统压力信号校准,单位:0.01MPaLDSM0.0-D6400,VD50MOVDVD50,VD100/D+256,VD100Network4//高压1#泵,单位:0.1MPaLDSM0.0-D6400,VD60MOVDVD60,VD108/D+64,VD108Network5//高压2#泵,单位:0.1MPaLDSM0.0-D6400,VD70MOVDVD70,VD112/D+64,VD112END_SUBROUTINE_BLOCK运行后监控发现以下问题:AIW0、2、4、6的值只有0~2,而到VD40、50、70、80的数值却在大范围跳动,用万用表在每个输入端均量不到电流、电压。请教问题出在哪里,谢谢