【摘要】 以西门子S7- 2 0 0CPU2 16型可编程控制器 (PLC)对JA2 1- 160型机械压力机的控制为例 ,论述了对该控制过程进行计算机仿真的必要性 .明确指出该仿真程序应具备监测PLC的I/O状态、监控PLC的运行结果和仿真曲柄连杆机构的运动过程三大功能 .指出PLC和上位机之间的通信对该仿真过程的影响是至关重要的 ,而该仿真通信软件由存储于PLC内和上位机内的两大部分程序组成 .上位机和PLC之间的通信应采用自由端口协议方式 .通过使用PLC的内部控制字SMB30和SM 4 5、设置“硬件板 /鼠标”、另设一组变量存储控制信息及使用VisualBasic 6 0中的MSCOMM通信控件等方法 ,实现了机械压力机PLC控制的仿真通信 ,并成功地应用于实践之中更多还原

【Abstract】 The Programmable Controller(PLC) control of JA21-160 mechanical press is taken for an example of SIMATIC S7-200 CPU216 PLC.The necessity of computer emulation for the control process is described, and it is pointed out that the emulation software must have three main functions,which show the state of PLC I/O,monitor the running results of the PLC and emulate the movement of the crank link mechanism.It is pointed out that the correct communication between the PLC and the personal computer for emulation is utmost important.The emulation communication software is composed of two programs stored in PLC and personal computer respectively. The emulation communication for PLC control of mechanical press is correctly accomplished by applying free port protocol mode, using SMB30 and SMB4.5 control bytes in the PLC,setting “hardware board/mouse”,adding a set of variables to store control information and adopting MSCOMM communication control in Visual Basic 6.0,etc.The software has been applied to practice successfully.更多还原