LabVIEW与S7-1200系列PLC基于Modbus TCP/IP协议的通信方法

The means of communication for LabVIEW and S7- 1200 PLC based on Modbus TCP / IP protocol

虚拟仪器(Lab VIEW)开发环境与PLC之间可通过RS-232、RS-485、以太网等多种接口进行通信,通信协议可使用PLC厂家开发的非开放协议(如西门子公司的PPI协议),也可使用开放的协议如施耐德公司开发的Modbus。随着越来越多的PLC本体集成以太网接口,采用Modbus TCP/IP协议的基于以太网接口的通信方式被广泛应用到电气设备中。实践证明,这种通信方式成本低廉,编程简单,可大大缩短程序开发时间并降低电气硬件成本。

LabVIEW can communicate with PLC by RS -232, RS -485, Ethernet and so on, the communication protocol can use non open protocol（ such as Simens＇ PPI protocol） ,it also can use open protocol（ such as Modbus that developed by Schneider）. As more and more PLCs integration Ethernet interface, the means of communication using Modbus TCP/IP protocol based on Ethernet has been widely applied to electrical equipment. The practice has proved that this means of communication with low cost, programming simple, it also can greatly short- en the develooment time and reduce the cost of electrical hardware.