期刊名称：International Journal of Future Generation Communication and Networking
印刷版ISSN：2233-7857
出版年度：2015
卷号：8
期号：3
页码：89-96
DOI：10.14257/ijfgcn.2015.8.3.09
出版社：SERSC
摘要：This paper analyzes several factors affecting the reliability of RS485 fieldbus communication, and then establishes the equivalent circuit model in order to solve bias resistor. The value range of bias resistor on the fieldbus is 556Ω~716Ω, which is determined by using the law of KCL and current limiting method. Furthermore the best value of bias resistor is derived about 670Ω for different unit loads based on the relationship between number of network nodes and the value of bias resistor, and the corresponding maximum network nodes of fieldbus are determined too. The research of this paper provides theoretical basis and engineering design guidance for the application of RS485 fieldbus.
