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What are the reasons for errors when using an electromagnetic flowmeter? There are many things to keep in mind when utilizing an electromagnetic flowmeter, as even minor carelessness can lead to measurement errors. Today, we will explain to you what the common causes of errors in electromagnetic flowmeters are 1. The liquid inside the tube is not completely filled. Due to insufficient back pressure or an improper installation location of the flow sensor, the liquid in the test tube was not filled completely. When there is a small amount of gas inside the tube, it causes the measurement results to deviate from the actual values, resulting in minor errors; when there is a large amount of gas present, the measurement values become unstable and the output fluctuates, leading to significant errors in the measurements, which cannot be considered accurate results. 2. The liquid being tested contains solid components. When this occurs, electromagnetic flowmeters usually experience the following problems: slurry noise, dirt accumulating on the motor surface, the lining being worn or covered by deposits, a reduction in the flow area, and the formation of conductive or insulating deposits on the electrodes or lining. If the deposits contain conductive materials, it is very likely that the flow signal will be short-circuited, causing malfunctions in the instrument. 3. Improper selection of materials for the electrodes and grounding ring. Electromagnetic flowmeters that experience failures due to a mismatch between the material and the medium being measured have components in contact with the medium, namely the electrodes and the grounding ring; apart from corrosion issues, an improper match mainly leads to surface effects on the electrodes. Whether the electrode can reliably detect the flow signal is crucial for the performance of the flow meter. The ground ring serves to establish an electrical connection with the dielectric, through a ground wire and a zero potential. When the process pipeline connected to the sensor is made of plastic or has an insulating coating, a grounding ring must be installed; otherwise, the instrument will not function properly. 4. There may be crystals present in the test liquid. Electromagnetic flowmeters should be used with caution when measuring chemically reactive materials that tend to crystallize; under normal temperature conditions, proper measurement is possible. Since the pipes used for transporting these fluids have good heat-insulating properties, crystallization does not occur during operation. However, it is difficult to provide heat insulation for the measurement tube of electromagnetic flowmeters; as a result, as the fluid flows through the tube, cooling can cause a layer of crystals to form on its inner wall. Since crystallization problems also arise when using flowmeters based on other principles, in the absence of any better alternatives, an “oring” type electromagnetic flowmeter with a very short measurement tube can be used, along with enhanced heat insulation for the pipeline upstream of the electromagnetic flowmeter. Regarding the pipeline connection method, ease of installing and removing the flow sensor is taken into account, so that it can be easily removed for maintenance once crystallization occurs. 5. Problems caused by liquid conductivity exceeding the allowable range. Oscillations may also occur if the liquid’s conductivity is close to the lower limit value. Since the lower limit specified in the manufacturer’s instrument specifications is the lowest value that can be measured under optimal operating conditions, and real-world conditions cannot always be ideal, it is common to encounter low-conductivity distilled water or deionized water whose conductivity is close to the lower limit specified in the electromagnetic flowmeter specifications; as a result, fluctuations in the output occur during use. It is generally believed that the lower limit value of conductivity that can be measured stably is 1 to 2 orders of magnitude higher. 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