Research Of The Lonworks Technology Application To Building Automation System

Since the reforms and opening-up, the scale of architecture lies on the top of the same industry. At the same time, it is highly required for the Intelligent Buliding. Intelligent Builiding is the essential outcome which fits the development of economics and progress of the living standard. Because the number of objects which need tu be monitored are increasing, it is much necessary to build a kind of system which is provided with the uniform criterion, agile configuration, high reliability, convenient maintenance, good founction and low price, and so on. The development of the Building Automation System (BAS) that is one of the important parts of the Intelligence Building has much important meaning. LonWorks technique is a kind of new-style fieldbus that has developd rapidly during the recent years. It is widely used in the fields such as building, transport, energy sources, and so on, which put computer, networks and control together. It integrates all of the seven layer protocol of ISO/OSI. In the meantime, it is provided with communication and control function, agile establishment and good opening. Now LON has become one of the most popular fieldbuses.In this paper, a set of BAS which is based on the LonWorks technique is built. The system includes tempertrue control nodes, three-phase parameter collection nodes, alarm monitoring nodes, and so on. Through the central monitoring system, the motion of the system is managed uniformly. Through understanding of the overall function of the system, the design requirement, hardware circuits, software design are discussed in detail, and Electro Magnetic Compatibility of the system is analysed.The program of the person-manchine operation interface is wholly compileded through Visual Basic language. PC is connected with LonWorks networks by a LonTalk Protocol adapter. MC143150 Neuron chip is adopted as the CPU of every function node and the programs are compiled by Neuron C language. The system adopts tuisted-pair as its transfer media. Since only a few nodes are used and the nodes are distributed nearly less than 500m, one subnet is surficient and the router is not needed.