Design And Optimize Of The Intelligent Electromagnetic Flowmeter System

Electromagnetic flowmeter, which is based on Faraday's induction law, is a velocity-type flowmeter. On the base of analyzing the development status and trend of the electromagnetic flowmeter technology, the design idea of the intelligent electromagnetic flowmeter based on the Intel 80C196KC are put forward, on this basis, the hardware system and software system of microprocessor based the intelligent electromagnetic flowmeter are developed.On the design of the electromagnetic flowmeter hardware system, we adopt the low frequency rectangle wave excitation technology whose frequency is alterable, and scheme out the keyboard management circuit, the analog-digital conversion circuit, the LCD display circuit. In order to enhance system's opening and communication function, RS-485 standard bus is applied to flow measure & system. In system digital part design,all outer logic circuits of Single chip microcomputer are implemented in CPLD.That makes the volume of the system smaller and improve the reliability of system.On the design of the electromagnetic flowmeter software system, we adopt the C196 language as the program tool. We adopt the modular designing method, and make full use of the functions what the Single chip microcomputer offers. As a result, the following subroutines are programmed: the optional excitation models, A/D sample, the flux processing and compute, the keyboard management, and the LCD display. These designs not only simplified the program structure, but also improved real-time performance, security, and precision of the system. Moreover, the time of debug the system's software is saved. After finishing the program, it is showed that the optional excitation model is convenient, data's confidentiality,the flowmeter is running well and was easy to be operated,and the system's anti-interference functions is very strong.