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A brief analysis of maintenance methods when sewage flow meters are not in use: For HKE series sewage flow meters, when they are not operational, it is necessary to apply scientific and appropriate methods for their protection and maintenance. After purchasing a sewage flow meter, there may be periods during which the measurement data is inaccurate. What causes this? It’s not actually a problem with the quality of the electromagnetic flow meter, but rather the fact that it has not been maintained in accordance with the instructions provided. I. Zero point checking and adjustment for the protection of HKE series sewage flow meters Before putting the HKE series sewage flow meters into operation, it is necessary to adjust the zero point while the liquid in the sewage flow sensor is at rest after powering them on. After it starts operating, it is also necessary to periodically stop the flow under the operating conditions in order to conduct zero-point checks; especially for electrodes that are prone to accumulation and contamination, as well as for non-clean fluids containing a high amount of solids, more inspections should be carried out during the initial phase of operation in order to determine an appropriate normal inspection interval based on experience. Electromagnetic flowmeters that use the communication excitation method are more prone to zero drift compared to those using rectangular wave excitation; therefore, more attention needs to be paid to their monitoring and adjustment. How to protect HKE series sewage flow meters during shutdown? Provide two examples of application errors that led to problems with the accumulation layers. In oil drilling cementing operations, the total flow rate of the cement slurry is a key technical parameter, and high-pressure electromagnetic flowmeters are often used for measuring it. The instrument is used intermittently; after use, the sensor measuring tube is rinsed with clean water, and it remains empty at other times. Due to inadequate cleaning, residual cement slurry on the inner wall of the measuring tube hardened into a thin layer; over the course of nearly two months, this layer accumulated and formed an insulating layer that covered the entire surface of the electrodes, resulting in abnormal operation until it became impossible to function at all. In the other device used for electrolytic cutting technology, an electromagnetic flow meter was employed to control the flow rate of saturated salt water; after use over a period of time, it was observed that the flow signal gradually weakened, and after 2 months the signal became zero. The factor is the accumulation of iron oxide on the tube wall during electrolytic cutting, which causes a short circuit. Removing the buildup results in immediate return to normal. II. Periodic checking of the sensor’s electrical functions as a form of protection for HKE series sewage flow meters. How to protect HKE series sewage flow meters when they are shut down? First, measure the resistance between the electrodes roughly. Disconnect the signal connection between the sensor and the converter, fill the sensor with liquid, and use a multimeter to measure the resistance values between the two electrodes and the ground terminal. These values should be within the range specified by the manufacturer, and the two measured values should be roughly equal to each other. Record the resistance value obtained from the initial measurement; this value is useful for identifying the causes of sensor faults in the future (such as whether the accumulation layer is conductive or insulating). Next, drain the liquid from the sensor, clean the inner walls, and after they are completely dry, use a megohmmeter to measure the resistance between the two electrodes and the grounding terminal.