的转换器选型注意事项：转换器选型针对分体式电磁流量计而言，分为壁挂式或盘装式二种，根据现场实际情况，主要考虑以下几点。 Note on converter selection for electromagnetic flowmeters: For the selection of split electromagnetic flowmeters, the converter selection is divided into two types: wall-mounted or panel-mounted. According to the actual situation on site, the following points are mainly considered.
Selection of output signal:
① Analog signal output: including 4-20mA output, 0-20mA output, 0-24mA output, 0-5V output, 0-6V output, 1-5V output, there are 6 types in total, users can choose one according to their needs Remember, you can only choose one of these 6 kinds of outputs, you cannot choose two kinds of outputs at the same time.
Digital communication: RS485 output. See the manual for detailed parameters.
Frequency / pulse output: This type of pulse output can be defined by the user. One type can be defined as the frequency corresponding to 1KHz, and the frequency corresponding to the flow rate in the range is reduced proportionally. , 0.01m3).
②Working environment temperature: -10 ℃-+ 55 ℃;
Protection level: IP65
是基于法拉第电磁感应定律的速度式电磁流量计。 Jiangsu Jinhu Dongxiang Instrument Co., Ltd.'s electromagnetic flowmeter is a speed-type electromagnetic flowmeter based on Faraday's electromagnetic induction law. Based on the measurement principle of electromagnetic flowmeter, an LDB electromagnetic flowmeter based on MSP430F149 single-chip microcomputer is designed. The circuit is based on MSP430F149 single-chip microcomputer, which simplifies the design of peripheral hardware circuits and realizes the measurement and accumulation of liquid flow. The overall block diagram of the design, part of the hardware circuit and control software flowchart are given in the article. The LDB-type electromagnetic flowmeter designed in this paper has been put into production. The actual application shows that the design has the characteristics of high accuracy, low power consumption and strong reliability, which basically meets the design requirements. 2. The electromagnetic flowmeter of Jiangsu Jinhu Dongxiang Instrument Co., Ltd. can effectively avoid strong power equipment, high frequency equipment, and strong power switch equipment; avoid the influence of high temperature heat and radiation sources, avoid strong vibration places and strong corrosive environments Etc. At the same time, we must consider the convenience of installation and maintenance. 具有保存每天２４小时的流量数据、停电时间、零流量时间等多种数据及报警等功能。 3. The electromagnetic flowmeter has the functions of saving 24 hours of daily flow data, power failure time, zero flow time and other data and alarm functions. Every day, only one or two short messages can be used to obtain 24 hours a day of measurement data at a measurement point. It can also be set according to user needs. Adopting the technology of combining electromagnetic vortex flowmeter and GSM network, the initial investment in establishing the water flow monitoring system is only 1/3 to / 5 of the radio station method. The operating cost after the system is set up is only once or twice a day. The cost of text messages. Eliminated the use of frequency and electricity and maintenance costs during use. 4. The display method, communication method and data storage of the flow detection instrument are important components of the instrument. Traditional electromagnetic flowmeters generally use LEDs or segment LCDs in the display mode. They can only display numbers, letters, Chinese characters, and some rough patterns. In data storage, information storage is generally stored in binary mode, which does not have versatility and storage capacity. Small; In communication method, RS 232 or RS 485 is generally used, and its openness is not high. 5． Sensor installation in vertical pipelines When measuring gas flow, the sensors can be installed in vertical pipelines with unlimited flow directions. If the measured gas contains a small amount of liquid, the gas flow direction should be from bottom to top. When measuring liquid flow, the liquid flow should be from bottom to top: this will not add additional liquid weight to the probe. 6. The sensor is installed on the side of the horizontal pipe No matter what kind of fluid is measured, the sensor can be installed on the side of the horizontal pipe, especially for measuring superheated steam, saturated steam and low-temperature liquids. If conditions permit, it is better to use side mounting, so the temperature of the fluid has less effect on the amplifier. 7. This method is generally not recommended for sensors mounted in a horizontal pipe. This installation method is not suitable for measuring general gases and superheated steam. Can be used to measure saturated steam, suitable for measuring high temperature liquids or situations where pipes need to be cleaned frequently. 8. When the sensor is installed on a pipe with a thermal insulation layer to measure high-temperature steam, the thermal insulation layer cannot exceed a third of the height of the bracket at most. 9. In order to solve the above-mentioned shortcomings, a 32-bit ARM processor and an embedded Linux operating system were used to develop an electromagnetic flowmeter with information, graphics, and networking. It adopts T FT color LCD display mode, which can not only display the flow data but also the flow curve, which improves the quality and content of the display. The JFFS2 file system is used for data storage in a file format, and the storage capacity can reach 1 MB.