Hierarchical hybrid control network design based on LON and master-slave RS-422/485 protocol

Abstract

Aiming at the weaknesses of LON bus, combining the coexistence of fieldbus and DCS (Distributed Control Systems) in control networks, the authors introduce a hierarchical hybrid control network design based on LON and master-slave RS-422/485 protocol. This design adopts LON as the trunk, master-slave RS-422/485 control networks are connected to LON as special subnets by dedicated gateways. It is an implementation method for isomerous control network integration. Data management is ranked according to real-time requirements for different network data. The core components, such as control network nodes, router and gateway, are detailed in the paper. The design utilizes both communication advantage of LonWorks technology and the more powerful control ability of universal MCUs or PLCs, thus it greatly increases system response speed and performance-cost ratio.

Keywords

LON / fieldbus / master-slave RS-422/485 protocol / hierarchical hybrid control networks / router / gateway / networks integration