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Maintenance methods for electromagnetic flowmeters 1. Daily maintenance It is necessary to conduct periodic visual inspections of the electromagnetic flowmeter (unit: cubic meters per second). Check the environment surrounding the instrument, remove dust and dirt, ensure that no water or other substances get inside, verify that the wiring is in good condition, and check whether there are any newly installed devices with strong electrical properties, such as wave-particle emitting equipment, or new wires running across the instrument. If the medium being measured tends to contaminate the electrodes or cause scaling and precipitation inside the measurement tube, cleaning and descaling should be carried out regularly. 2. Fault detection If an electromagnetic flowmeter stops working properly after it has been in operation for some time, the first step is to check the external conditions of the flowmeter – such as whether the power supply is functioning properly, whether there are leaks in the pipes or if they are not fully filled, whether there are bubbles inside the pipes, whether the signal cable is damaged, and whether the output signal from the converter (i.e., the input circuit for the downstream instruments) is open-circuited. The electromagnetic flowmeter is a new type of flow measurement instrument that developed rapidly in the 1950s and 1960s along with the advancement of electronic technology. An electromagnetic flowmeter is an inductive instrument manufactured based on Faraday’s law of electromagnetic induction, used to measure the volumetric flow rate of conductive media within a pipe. Be sure not to disassemble the flow meter blindly. 3. Sensor (transducer) inspection: Testing equipment: one 500MΩ insulation resistance tester and one multimeter. The function of an electromagnetic flowmeter is to generate a uniform direct-current or alternating-current magnetic field. The DC magnetic circuit is implemented using permanent magnets, which have the advantage of a relatively simple structure and are less affected by alternating magnetic fields. However, they can cause polarization of the electrolyte liquid flowing through the measurement conduit, with positive ions surrounding the negative electrode and negative ions surrounding the positive electrode – that is, a polarization phenomenon of the electrodes. This leads to an increase in the internal resistance between the two electrodes, thereby severely affecting the proper functioning of the instrument. Test (TestMeasure) procedure: 1) With the pipeline filled with the medium (the substance that plays a key role), use a multimeter to measure the resistance values between terminals A, B, and C; the resistance values between A and C as well as between B and C should be roughly equal. If the difference is more than 1 times, it may be due to leakage at the electrode, or the presence of condensed water adhering to the outer wall of the measurement tube or inside the junction box. 2) With the lining dry, use a MΩ meter to measure the insulated resistance between A-C and B-C (it should be greater than 200 MΩ). The wastewater flow meter consists of an electromagnetic flowmeter sensor and a converter. It operates based on Faraday’s law of electromagnetic induction, and is used to measure the volumetric flow rate of conductive liquids with a conductivity greater than 5 μS/cm; it is an inductive instrument for measuring the volumetric flow rate of conductive media. Then use a multimeter to measure the resistance between terminals A and B and the two electrodes inside the measuring tube (it should be in a short-circuit state, with current flowing directly from the power supply terminals without passing through the device). If the insulation resistance is very low, it indicates electrode leakage; the entire flow rate (in cubic meters per second) should be sent back to the factory for repair. If the insulation level declines but remains above 50 MΩ, and the results of the inspection in step (1) are normal, it may be that the outer wall of the measuring tube is damp; in such a case, use a hot air blower to dry the interior of the enclosure. 3) Measure the resistance between X and Y using a multimeter; if it exceeds 200Ω, the excitation coil and its leads may be open-circuited or have poor contact (loose wiring). Remove the terminal block for inspection. 4) Inspection The insulation resistance between X, Y, and C should be above 200 MΩ; if it decreases, the interior of the enclosure should be dried using hot air. During actual operation, a decrease in the insulation quality of the windings will lead to increased measurement errors and unstable output signals from the instrument (Explanation: stable and consistent) ； No change). 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