Design Of Monitoring System Based On The Intrinsically Safe And Low-power Gas Ultrasonic Flowmeter

Natural gas is a kind of clean energy with an enormous potential for development.With the increased use of natural gas,the demand for measuring device will increase.The gas ultrasonic flowmeter has many advantages to traditional gas flowmeter,so it will be widely used.However,the operating environment of flowmeter has been more and more complex,which has caused much inconvenience for research and maintance personnel.In order to solve this problem,based on an intrinsically safe and low-power gas ultrasonic flowmeter,a monitoring system with three-layer of "field LAN-server-client" has been designed in this dissertation.The main content of this dissertation is as follows.(1)The design of monitoring system's hardware.GPRS communication is used for remote data transmission.A field LAN is made up by data acquisition terminals.It uses RF communication and RS485 communication as networking mode to meet different usage scenarios.Besides,the data acquisition terminals hardware with MSP430 as the core is also designed in the dissertation.Data acquisition terminals not only meet the functional demand but also satisfy low power and intrinsically safe.(2)The design of monitoring system's software.It includes design of data acquisition terminal's software,server's software and client's software.Data acquisition terminal's software is designed in C language based on MSP430.It achieves the function of networking,data acquisition and remote communication.What's more,it also has low-power consumption.The server's software is designed by Lab VIEW and has the function of remote communication and data storage.The client's software is also designed by Lab VIEW and it is mainly used to deal with the user input.Finally,a prototype of monitoring system has been produced in this dissertation.The data acquisition terminal has got an explosion-proof grade of ia ?B T4.It can continuously run for more than 4 years with two 19 Ah lithium batteries.The monitoring sytem can remotely monitor the running states of gas ultrasonic flowmeters,which has great significance for accelerating the speed of research and reduceing the maintenance for gas ultrasonic flowmeter.