Study On The Communication System Of Electromagnetic Flowmeter Based On Modbus

With the development of computer technology, network technology and integrated circuit technology, industrial control system becomes an open network. Fieldbus is an opening, digital and multipoint communication network at the lower level of the factory automation hierarchy. It has become the research focus in automatic field and has greatly improved the performance of the traditional control system.Based on ARM processor and Modbus protocol, embedded system technology is used to design the high-end electromagnetic flowmeter. It greatly improves the display mode and communication performance, which makes the electromagnetic flowmeter more intelligent and networking. Research on the communication of electromagnetic flowmeter is important for the flow measurement technology. The thesis mainly focuses on the following research works:(1) The principle and characteristics of electromagnetic flowmeter are reviewed. At the same time, the current status and features of Fieldbus are discussed.(2) A communication module based on Modbus protocol has been designed. A master-to-slave Distributed Data Acquisition and Communication System is implemented by referring to the Modbus protocol. The system has the advantage of opening and is easy to operate and maintain.(3) Most of tests are carried out to verify the system. Results show that the proposed system is effective and the data can be transferred using multipoint half-duplex mode.