How to choose 3051 differential pressure transmitter and research direction
The 3051 differential pressure transmitter is a transmitter that measures the differential pressure of the pipeline. The following focuses on how to correctly select the 3051 differential pressure transmitter and the feasibility study direction.
First, the correct selection of 3051 differential pressure transmitter
With the continuous advancement of technology, the 3051 differential pressure transmitter has gradually become the first choice in most industries, but at the same time, when selecting the differential pressure, it is necessary to comprehensively consider the influence of the cut-off temperature and working environment. The type of instrument must be selected strictly according to the process requirements, thus providing effective protection for the normal operation of the instrument and the safety of production activities. The selection of the 3051 differential pressure transmitter mainly has the following six points.
(1) The nature of the measured medium. Observe the corrosiveness, viscosity, temperature and other characteristics of the measured medium, determine the standard and level of the selected instrument, thereby improving the efficiency of use of funds, and easier to install and maintain. If the measuring medium is relatively clean, the standard differential pressure can be used in the selection of the differential pressure. When the measuring medium is viscous or crystallization, the differential pressure of the external diaphragm is selected, thereby effectively preventing the pressure measuring hole from being blocked by the measuring medium, better protecting the differential pressure and prolonging the service life.
(2) The scope of measurement. Generally speaking, the range of the differential pressure transmitter is adjustable within a certain range, and the optimal range of the range is 1/3 to 2/3 of its range, which can effectively improve the measurement accuracy, especially for micro For differential transformers, the setting of the range is more critical. The upper limit of the measured pressure in the system is clarified, and the transmitter is selected based on this, so that the pressure range is maintained at about 1.5 times the upper pressure limit. This is because the water pressure measurement and processing in most systems are affected by peak fluctuations, and pressure sensors are often affected by transient peak changes. Usually, in order to effectively reduce the pressure glitch, a buffer is often used for buffering, but this also affects the response speed of the sensor. Therefore, it is necessary to select the transmitter based on the accuracy, range and stability of the pressure.
(3) Accuracy level. The range is selected by the process tolerance and the pressure measurement range. Then, the allowable error range of the instrument is calculated by the process tolerance range, and the % and ± of the calculated value are removed, and the accuracy can be obtained. In the absence of the corresponding level standard, the accuracy level can be used as a reference standard. There are different standards for the accuracy level of differential pressure transmitters in different countries. In countries such as the United States and China, the accuracy of the sensor is marked in the best part of the linearity. The commonly used accuracy of 10%-90% of the measurement range is the accuracy of the calibration method. The accuracy of the calibration in Europe is the most linear. The bad part is labeled, which means the precision between 90% and 100% and the accuracy between 0 and 10%. The 1% marked with the European precision notation is equivalent to 0.5% of the Chinese precision mark.
(4) Output signal. According to the different needs of the collection, there are many differential pressure output signals on the market. The common ones are 4mA~20mA, 0mA~20mA, 0V~10V, 0V~5V. Among them, 4mA~20mA and 0V~10V are the most commonly used. Except for the 4 mA to 20 mA two-wire signal, the other signals are three-wire signals.
(5) Medium temperature. Under normal circumstances, the conversion of the differential pressure signal is realized by the electronic circuit, so the temperature of the measured medium of the differential pressure is often between -30 ° C and +100 ° C. When the temperature is too high, the medium is often cooled by a condensation bend, which requires a lot of cost for the direct production of the high temperature differential pressure by the manufacturer.
(6) Others. According to the practical needs, the measurement range of the transmitter in some occasions needs to be moved within the measurement range according to the installation position of the site. At present, smart transmitters have been promoted in a wide range, with high stability, easy adjustment, high precision and other excellent features. In addition, in some special occasions, it is necessary to fully consider the differential voltage supply voltage and the protection and explosion protection of the connection interface.
Second, the application research direction of 3051 differential pressure transmitter
(1) Intelligent transmitter. Compared with the traditional differential pressure transmitter, the intelligent differential pressure transmitter has broken through the simple conversion of the measured process parameters, and has the functions of self-diagnosis, A/D conversion and remote control operation, and gradually realizes the machine- Electricity-integration. The new composite sensor technology can realize the integrated integration of temperature, static pressure and differential pressure sensors by the same semiconductor chip, which effectively reduces the static pressure and temperature error of the transmitter and greatly improves the accuracy of the transmitter. If the accuracy of the measurement is high and its accuracy directly affects the accuracy of the measurement results, an intelligent transmitter is required.
(2) Development towards miniaturization of volume. Conventional differential pressure transmitters are bulkier due to their large size and must be attached with a certain amount of support for effective installation. In order to change this situation, the differential pressure transmitter has gradually turned to miniaturization. Applying a more stable integrated circuit sensor to the transmitter can improve the stability of the transmitter and enable the transmitter to be small
To achieve economical and convenient installation of the transmitter.
(3) Digital signal transmitter. Currently, 4mA to 20 mA DC current analog signals have been widely used in control instruments in the process industry. Driven by the development of microcomputer control systems, the establishment of digital signal excuses was quickly realized, and higher transmitter standards were proposed.
To ensure stable and safe operation of instrumentation, manufacturers must improve the accuracy of differential pressure transmitter monitoring. This requires adhering to the correct selection and use method to select the appropriate differential pressure transmitter, thus improving the accuracy, stability and timeliness of practical applications.