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Usually, when using electromagnetic flowmeters, improper operating methods are employed. This can prevent the electromagnetic flowmeter from functioning properly; such issues usually arise from changes or unevenness in the conductivity of the liquid being measured by the flowmeter, which causes fluctuations in the zero point when there is no flow, and variations in the output signal when flow is present. Therefore, the flowmeter should be placed far away from the point where the liquid is injected or downstream of the section of the pipeline where chemical reactions occur; it is best to install the flow sensor upstream of these locations. If the liquid contains solid particles, or if impurities accumulate on the inner wall of the flow meter tube, or if scaling forms on that inner wall, or if the electrodes are contaminated by grease or other substances, zero-point drift can occur. Due to the fact that the scaling on the inner and outer walls as well as the degree of electrode contamination cannot be exactly the same and symmetrical, the equilibrium condition established during initial zeroing is disrupted. Positive measures include removing dirt and accumulated scale; if the zero point does not change much, attempting to reset it again can also be tried. No matter how well the advertisements for electromagnetic flowmeters are made, they can’t compare to the high quality of the flowmeters produced by Jiangsu Hengda Instruments! A decrease in the insulation of the signal circuit can cause instability at the zero point. The main cause of insulation degradation in the signal circuit is insulation degradation at the electrode areas, but it is also possible that the insulation of the signal cables and their connection terminals has degraded or been damaged. This is because in some cases, the field conditions can be extremely harsh; even a slight neglect in ensuring proper sealing of the instrument covers and wire connections can allow moisture, acidic fumes, or dust particles to enter the instrument junction boxes or cable shielding layers, thereby leading to insulation degradation. The inspection of the insulation resistance of the signal circuit is carried out separately for the cable side and the flow sensor, using a megohmmeter for testing. It can be done first since the signal cable is easy to detect. Liquid-filled electromagnetic flowmeters: contact resistance at the electrode surface and insulation resistance of the flowmeter electrodes when there is no liquid in the tube. Changes in the condition of the electrical equipment near the flow sensor (such as an increase in leakage current) lead to variations in the ground potential, which in turn can cause fluctuations in the zero point of the electromagnetic flowmeter. External disturbances such as stray currents in pipelines can be mitigated through proper grounding of the electromagnetic flowmeter; it is generally recommended that the grounding resistance be less than 10, and the flowmeter should not share the same grounding system as other motors and electrical devices. Sometimes, when the environmental conditions are favorable, an electromagnetic flowmeter can function properly even without being grounded. However, once those favorable conditions are no longer present, the instrument will start to malfunction, and conducting inspections at that point will involve a lot of hassle. Electromagnetic flowmeters are widely used in industries such as steel, power, petroleum, chemicals, coal, mining, papermaking, water supply and drainage, food, and pharmaceuticals. 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