| Electromagnetic flowmeter, which is based on Faraday's induction low, is a velocity-type flowmeter. Electromagnetic flowmeters were widely used in many fields.On the base of analyzing the development status and trend of the electromagnetic flowmeters technology, this article uses MCU and IC to design the intelligent electromagnetic flowmeters, which uses battery feed. The measuring principle of electromagnetic flow meter is introduced, and the general schematic of the hardware design is given.The MSC1211 microcontroller is used in the design for liquid flow measurement and cumulating, so the hardware structure is simplified. Three-valued low-frequency square-waveform exciting mode was used, which effectively improved the stability of the null point and reduced power consumption. In this system, signals amplify circuit, filter circuit, LCD circuit, keyboard circuit and I/O circuit were designed. Output circuit uses RS-232 communicate interface which can be used to connect with emulator and also can be used to transmit dates. Output standard current of 4～20mA, signals of frequency and alarm was designed in this system. On the base of this design, software Multisim was used to simulate all hardware circuits and all this validate the system's feasibility. The system has the advantage of simple structure, high precision and low power dissipation.In the design of software, modularized methods were used, and flow diagrams of every parts was given, also the diagram of A/D conversion was designed.On the base of hardware and software design, the system's interferes was analyzed and the resolve methods was given.
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