手写的一个定时器 可以通用其他plc 
SettingTimeold :=SettingTime*1000.0;
IF Enable  THEN
     IF NOT DelayedComplete AND  CurrentTime<=SettingTimeold THEN
          CurrentTime:=CurrentTime+100.0;     (*利用扫描周期计算时间,扫描周期100ms*)
           IF CurrentTime>=SettingTimeold THEN 
                   CurrentTime:=0.0;
                    DelayedComplete:=TRUE;
            END_IF;    
     END_IF;
 ELSE 
          DelayedComplete:=FALSE;
            CurrentTime:=0.0;
END_IF;    
EnableOld :=Enable ;