Magnetic inductive flowmeter main parameters and adjustment methods

Project Overview

Electromagnetic flowmeter is an instrument widely used in industrial fluid measurement. It uses Faraday's law of electromagnetic induction to measure the flow of conductive liquid. In order to ensure that the electromagnetic flowmeter can work accurately and stably, we need to understand its main parameters and master the corresponding adjustment methods.

First, let’s discuss the main parameters of electromagnetic flowmeter. These parameters mainly include measurement range, accuracy, repeatability, flow sensor size, material, temperature range and pressure range, etc. The measurement range refers to the flow rate that the flowmeter can measure. It depends on the diameter of the flowmeter, the sensor type and the manufacturer's design. Resolution is the smallest change in flow that the flowmeter can distinguish. It determines how accurately the flowmeter can measure flow. Accuracy is the closeness between the flow meter measurement and the actual flow value, usually expressed as a percentage or absolute error. Repeatability reflects the consistency of results when a flowmeter repeatedly measures the same flow rate under the same conditions. In addition, the size, material, temperature range and pressure range of the flow sensor are also important factors that affect the performance of the flow meter. Next, we focus on the adjustment method of electromagnetic flowmeter. The main purpose of adjusting an electromagnetic flowmeter is to calibrate its measurement accuracy to ensure its accuracy in practical applications. Specific adjustment steps include zero point calibration, span calibration, coefficient calibration, etc. Before performing these calibrations, we need to understand the density, conductivity and other parameters of the liquid being measured in order to perform better calibrations.

Zero point calibration is to adjust the output signal to zero when there is no flow in the measured pipeline, and is achieved by adjusting the zero point parameters. Range calibration requires inputting a known flow value and adjusting the range parameters so that the output signal is within the design range. In addition, we also need to adjust the temperature and pressure coefficients according to the temperature and pressure of the liquid being measured to improve the accuracy of the measurement. When adjusting the electromagnetic flowmeter, we also need to pay attention to some key adjustment parameters. For example, the excitation current is the current required to generate the magnetic field for measurement. Increasing the excitation current can improve measurement accuracy, but it will also increase power consumption. Therefore, we need to adjust the excitation current according to actual needs. The inner diameter of the measuring tube directly affects the flow velocity distribution of the fluid, which in turn affects the measurement accuracy. Therefore, when selecting the inner diameter of the measuring pipe, we need to ensure that it is consistent with the actual pipe size. The sampling frequency determines the measurement speed of the flow meter. Increasing the sampling frequency can improve the measurement accuracy, but it will also increase the burden on the processor. Therefore, we need to choose an appropriate sampling frequency based on actual needs.

During the adjustment process, we also need to pay attention to some details. For example, when performing zero point adjustment, ensure that the fluid is completely stationary to avoid errors caused by fluid flow. When adjusting for full scale, we need to run the fluid at maximum flow and record the reading from the flow meter to ensure it reads accurately at maximum flow. In addition, the material selection of the electromagnetic flowmeter is also an important factor affecting its performance. The material of the flow sensor should have good corrosion resistance and wear resistance, especially when dealing with corrosive or abrasive flows.body time. Therefore, when choosing an electromagnetic flowmeter, we need to choose the appropriate material based on the properties of the liquid being measured. In short, understanding the main parameters of the electromagnetic flowmeter and mastering its adjustment methods are the keys to ensuring its accurate and stable operation.