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The inspection method for electromagnetic flowmeters mainly involves checking the condition of the working electrode and the excitation coil: For electrode inspection, use the resistance setting on a multimeter to determine whether each electrode is conductive; touch the electrode with a test probe and then use the same probe to measure the corresponding terminal in the wiring box; if there is continuous conductivity, then there is no problem. As for checking the excitation coil, use the multimeter’s resistance setting to measure the resistance of the coil. This value is neither infinite nor close to zero; it should normally range from a few dozen ohms to several hundred ohms (the resistance varies depending on the type of flow meter). As for determining whether an electromagnetic flow meter is of good quality or not, visual inspection and instrument-based testing can be used. The GS8 device can be employed to check whether the parameters such as the resistance of the sensor’s excitation coil, the insulation resistance between the signal wires, and the grounding resistance meet the standards set before the product leaves the factory. It is also necessary to ensure that the flow meter’s converter can achieve the required precision levels in terms of zero point setting and current output. The specific analysis and testing methods are as follows: (1) Measure the resistance value of the excitation coil to determine whether there is an inter-turn short circuit in it (the resistance value between wires \"7\" and \"8\"); this resistance value should be between 30 and 170. If the resistance is the same as the factory record, the coil is considered good, and it can then be inferred that there has been no change in the magnetic field strength of the electromagnetic flowmeter sensor. (2) Excitation coils (wire numbers “1” and “7” or “8”); in the measurement of the insulation resistance of the humidity sensor, the resistance value should be greater than 20 megohms. (3) Measuring different resistance values when the working electrode comes into contact with the liquid (measurement line numbers “1” and “2” as well as “1” and “3”) indirectly influences the assessment of the overall development status of the surface of the study electrode and the lining material. Such as whether the surface of the electrode structure and the lining layer can support the deposition of a layer, and whether that deposited layer has good electrical conductivity or is insulating. The resistance value between them should be between 1 kOhm and 1 MOhm, and the resistance values for wire numbers \"1\" and \"2\" as well as \"1\" and \"3\" should be roughly symmetrical. (4) Close the valves on the pipeline and check the zero point of the electromagnetic flowmeter when the pipe is filled with liquid and no flow is occurring. Make appropriate adjustments as necessary.. (5) Inspect the signal cable of the electromagnetic flowmeter, check the insulation resistance of each wire in the cable, and ensure that the shielding is intact. (6) Use an instrument that has passed GS8 verification to measure the current output by the test data converter. When zero flow is given, the output voltage and current should be: 4.00mA ； When a 100% flow rate is given, the output control current time should be: 20.00mA. The error in the output operating current value should be better than 1.5%. (7) Measure the excitation current value (between terminals “7” and “8” of the converter); the positive and negative excitation currents should be within the specified range, approximately 137(5%) mA. 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