One. An overview of the liquid level measurement method of the pressure sensor.
The liquid level refers to the position of the liquid level in a sealed container or an open container. Through the measurement of the liquid level, the quantity of the material in the container can be known, so as to adjust the balance of the material flow in the container and the outflow, and ensure the materials required in each link of the production process. or conduct economic accounting;In addition, through the measurement of the liquid level, it is possible to know whether the production is running normally, so that the liquid level of the container can be monitored in time to ensure safe production and ensure the quality and quantity of products.Due to the influence of the physical properties, chemical properties and working conditions of the measured medium, liquid level measurement has always been a relatively weak link in engineering. In order to realize the automation of the production process better, a method for liquid level measurement using pressure sensor is proposed in this paper.
Common liquid level measurement methods and instruments include differential pressure level gauges, capacitive level gauges, buoyancy level gauges, ultrasonic level gauges, and laser level gauges.Compared with the above methods, using a pressure sensor for liquid level measurement not only has the advantages of high measurement accuracy, low cost, convenient use, and convenient signal transmission, but also can be used for liquid level measurement in sealed containers and open containers.Its working principle is similar to that of the differential pressure liquid level gauge, but the difference is that the measuring elements used are different, and the sensor is not in contact with the measured medium, so it is suitable to use a semiconductor sensor.
Second, the pressure sensor liquid level measurement method measurement system.
The test system framework includes pressure sensor, signal conditioning circuit, digital conversion interface, badge processor, keyboard and display interface, communication interface, etc. The selection of the pressure sensor and the design of the signal conditioning circuit are emphasized.According to the formula (4), the maximum differential pressure value that may act on the differential pressure sensor is estimated, so that the range of the differential pressure sensor can be determined according to the actual situation. Determining the accuracy level of the pressure sensor is based on the requirements of the liquid level measurement accuracy, whether it is necessary to set a temperature compensation circuit in the chip, or to set a signal conditioning circuit in the chip. In this way, the specific sensor model can be determined.
Third. Precautions for the liquid level measurement method of the pressure sensor.
1. In order to ensure the long-term stability of the pressure sensor, the actual position of the sensor is required to be higher than the maximum liquid level of the measured medium, and no harmful gas is allowed to enter the sensor;
2. If the sensor is close to the measuring instrument, four-wire wiring can be used; if the sensor is far away from the measuring instrument, six-wire wiring can be used, that is, voltage feedback can be used to eliminate measurement errors caused by unstable power supply voltage. The method is ratio measurement.
Due to factors such as ambient temperature, ambient pressure, and medium density, the measurement has a certain influence. Therefore, in some cases, the measurement results must be compensated to ensure a certain measurement accuracy.
Post time: Oct-18-2022