RS-485总线网络应用中的安全与可靠性

Safety and reliability during application of RS-485 bus network

控制领域中的分布式监控系统,具有节点多、传输距离远以及现场工作条件恶劣等特点,因此需要一种能够支持多节点、远距离通信及接收灵敏度高的总线来构成网络。利用RS＿485总线构成的网络符合这种要求,如ARCNet、CAN、INTERBUS＿S等,其物理层都是基于RS＿485总线标准。使用RS＿485总线构成自动控制系统的网络,具有设备简单,成本低等优点,但是如果在实际的工程应用中对RS＿485总线网络配置不当,将会影响整个网络通信的可靠性,甚至会损坏总线收发器(特别是接收器)而造成整个网络的瘫痪。作者结合RS＿485总线在雷达分布式监控系统中的应用,提出了保证RS＿485总线网络的安全性、提高通信可靠性的方法,在实际使用中收到了良好效果。

At present, the physical layers of commonly used field buses, such as ARCNET, CAN, INTERBUS_S are based on RS_485 bus standard. The automatic control network adopting RS_485 bus features simple structure and low cost. However, any misconfiguration of RS_485 bus network may reduce the reliability of communication over the whole network, and even damage the receiver and transmitter and disable the whole network. Some proposals have been made for the application of the RS_485 bus in the radar distributed supervisory control system to ensure the safety and reliability of communication.These methods proposed have been proved effective, as expected in practice.