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Today, the editor noticed that when using an electromagnetic flowmeter (http://www.yb1518.com/ProductShow_133.html) for measurements, no flow signal is generated regardless of how the measurement is carried out; what could be the reason for this? How should this be solved? Below, the editor has compiled some reasons why it does not display and corresponding solutions, in the hope of being helpful to everyone. I. The instrument does not output a flow signal. 1. Cause analysis: (1) Abnormal power supply to the instrument ； (2) Abnormal cable connection ； (3) The liquid flow conditions do not meet the installation requirements ； (4) Damage to sensor components or an adhesive layer on the inner wall being measured ； (5) Damage to the converter components. 2. Solution: (1) Confirm that power is connected, check whether the voltages output by the power circuit board are normal, or try replacing the entire power circuit board to determine its condition. (2) Check whether the cable is in good condition and the connection is correct. (3) Check the liquid flow direction and whether the tube is fully filled with liquid. For electromagnetic flowmeters that can measure in both forward and reverse directions, although measurement is possible when the directions are different, the displayed flow rate will indicate the wrong direction; this must be corrected. If removing the sensor is a time-consuming task, it is also possible to change the direction of the arrow on the sensor and reset the symbols displayed on the gauge. The pipes not being filled with liquid is mainly caused by an improper installation location of the sensors; measures should be taken during installation to prevent the pipes from not having enough liquid in them. (4) Check whether the electrodes on the inner wall of the transmitter are covered with a layer of liquid scum; for measurement liquids prone to scum formation, cleaning should be carried out regularly. (5) If it is determined that the fault is caused by damaged components of the electromagnetic flowmeter converter (http://www.yb1518.com/ProductShow_133.html), replacing the damaged components will resolve the issue. II. Fluctuations in output values 1. Cause analysis: Such faults are mostly caused by the influence of the measuring medium or external factors; once these external interferences are removed, the fault disappears on its own. To ensure the accuracy of measurements, such faults cannot be ignored either. In some production environments, excessive vibration in the pipes or liquid can cause the circuit board of the flow meter to become loose, which in turn can lead to fluctuations in the output values. 2. Solutions: (1) Determine whether it is due to process operations; if the fluid indeed experiences pulsations, then the flow meter simply reflects the actual flow conditions, and the fault will resolve on its own once the pulsations cease. (2) Electromagnetic interference caused by external stray currents, etc. Check whether there are any large electrical appliances or welders in operation in the environment where the instrument is installed; ensure that the instrument is properly grounded and that its operating environment is suitable. (3) When the pipeline is not filled with liquid or when there are bubbles in the liquid, both situations are caused by process-related factors. At this point, it is possible to ask the process technician to confirm that once the tube is filled with liquid or the bubbles subside, the output value will return to normal. (4) The transmitter circuit board has a plug-in design; due to the significant vibrations in the pipelines or liquids at the measurement site, this often leads to the loosening of the power supply board of the flow meter. If it becomes loose, the flow meter can be disassembled and the circuit board reattached. 3. The flow measurement value does not match the actual value. 1. Cause analysis: (1) Is the circuit board of the electromagnetic flow meter transmitter intact? (http://www.yb1518.com/ProductShow_133.html) ； (2) When the liquid flow rate is too low, tiny bubbles are present in the liquid being measured; these bubbles rise and accumulate above the pipeline, thereby changing the flow area of the liquid. In cases where there is a large amount of gas, interference signals are generated, which affects the accuracy of the measurements ； (3) Inaccurate measurements can occur due to poor connections in the signal cable, or as a result of a decline in the cable’s insulation properties over time ； (4) The parameter settings of the converter are inaccurate. 2. Solution: (1) Check whether the transmitter circuit board is intact. If the junction box gets wet or is corroded by corrosive liquids being measured, it can lead to a decline in the electrical equipment’s performance or even damage to it. The circuit board should be replaced at this time. (2) Ensure that the flow rate of the liquid being measured in the pipeline is above the minimum flow limit, so that the transmitter can function properly. (3) Check whether the connections of the signal cables and their insulation properties are in good condition; if the signal cables are loose, reconnect them ； If it is detected that the insulation of the cable does not meet the insulation requirements, a new cable must be replaced. For more information, please visit the company’s official website at http://www.yb1518.com/. Please keep this link when reproducing the content! http://www.yb1518.com/UploadFiles/2012717174126829.jpg