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Do you know what the fault symptoms of electromagnetic flowmeters are? Do you know the troubleshooting methods? Do you know anything about product selection? Do you understand the installation location and requirements? Do you know how to set parameters? Electromagnetic flowmeters are flow meters with high precision, high reliability, and a long service life; therefore, we pay great attention to every detail in the processes of designing the product structure, selecting materials, formulating manufacturing processes, carrying out production and assembly, as well as conducting final tests before the products leave the factory. Measurement of interference in the signal cable of electromagnetic flowmeters: Interference from external electrostatic and electromagnetic induction on the signal cable can cause changes in the zero point of the electromagnetic flowmeter. To determine whether the zero-point shift is caused by interference potentials from the signal cable, it is necessary to measure the general range of the interference and its impact on the electromagnetic flowmeter. Although the measurement range of electromagnetic flowmeters is 30:1, which is higher than that of vortex flowmeters and differential pressure flowmeters, it still has its limitations. Many customers compare them with water meters when ordering them, thinking that they can measure very low flow rates; generally, however, they can only measure flow rates of 0.1 m/s. Below this flow rate, it becomes difficult for electromagnetic flowmeters to provide accurate measurements. Therefore, it is necessary to clarify the traffic range at the initial stage of placing an order. When placing an order, it is not possible to specify the diameter based on the original pipe diameter; it is better to determine the instrument diameter according to your actual flow rate. From the above introduction, it is clear that this is an excellent flow meter product; it is chosen for measuring most liquid media. Therefore, it is necessary for us to understand the relevant performance characteristics and technical parameters of this product, as this will be of great help in ensuring its proper use in the future. Electromagnetic flowmeters identify problems by measuring the electrode contact resistance: the electrodes are the core components of the flowmeter, used to detect the signals generated by the liquid medium. By measuring the electrode contact resistance, it is possible to determine the resistance between the electrodes and the liquid, allowing for an indirect assessment of the overall condition of the electrodes and the lining surface, without the need to remove the flow sensor from the pipeline. This helps in analyzing the causes of faults. Measuring the polarization voltage between the electrode and the liquid will help determine whether faults such as unstable zero points or fluctuating outputs are caused by contamination or coverage of the electrodes. Use the 2V DC setting of a digital multimeter to measure the polarization voltage between each electrode and ground; electromagnetic flowmeters can be measured with power connected or without it. If the two measurement values are close to being equal, it indicates that the electrode is not contaminated or covered; otherwise, it means the electrode is contaminated or covered. The magnitude of the polarization voltage depends on the \"electrode potential\" of the electrode material and the properties of the liquid; the measured value can range from a few mV to several hundred mV. Since, in practice, the degree of contamination on the two electrodes during operation cannot be exactly the same and symmetrical, a non-symmetrical common-mode voltage is generated across the two electrodes. The asymmetric common-mode voltage becomes a differential-mode signal, causing zero offset. Only by mastering this knowledge can we identify the causes of faults in instruments. Next, we will explain how to identify issues with instruments by measuring the potential of ground faults; for example, changes in the condition of electrical machines near sensors (such as leakage current) can cause changes in the ground potential, which in turn leads to variations in the zero point. To check for any impact in this regard, short-circuit the converter’s working ground C terminal with the protective ground G terminal, and determine whether there is a ground potential variation by observing the zero point (or indication value). Determining the direction of stray current in pipelines sometimes involves identifying whether the source of such interference lies upstream or downstream of the flow sensor, in order to narrow down the search area and reduce or eliminate the impact of stray current interference. Although electromagnetic flowmeters have good reliability and generally do not get damaged, due to their working principle, the sensor electrodes are in constant contact with the liquid; over time, the surface of these electrodes is prone to contamination. For more information, please visit the company’s official website at http://www.yb1518.com/. Please retain this link when reproducing the content! http://www.yb1518.com/UploadFiles/2012717174126829.jpg