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Advantages and disadvantages of sewage flow meters; Advantages of sewage flow meters: Sewage flow meters can be used to measure industrial conductive liquids or slurries. No pressure loss. Sewage flow meters have a wide measurement range, and the diameter of electromagnetic flow transmitters ranges from 2.5 mm to 2.6 m. The price of electromagnetic flowmeters: Sewage flowmeters measure the volumetric flow rate of the fluid under operating conditions, and their measurement principle does not take into account the effects of the fluid’s temperature, pressure, density, or viscosity. Disadvantages of sewage flow meters: The application of sewage flow meters has certain limitations; they can only measure the flow rate of liquids that are conductive. Electromagnetic flow meters cannot be used to measure the flow rate of non-conductive media, such as gases and heated water used in water treatment. Additionally, its lining needs to be considered under high-temperature conditions. A wastewater flow meter determines the volumetric flow rate under operating conditions by measuring the velocity of the conductive liquid. According to the measurement requirements, for liquid media, the mass flow rate should be measured. Measuring the flow rate of a medium involves knowing the density of the fluid; different fluid media have different densities, and these densities change with temperature. If the price of an electromagnetic flowmeter is indicated without taking into account the fluid density, and only the volumetric flow rate at normal temperature is given, it is inappropriate. The installation and calibration of sewage flow meters are more complex than those of other flow meters, and stricter requirements are applied. Transmitters and converters must be used together; it is not possible to use instruments of two different models with each other. When installing the transmitter, from the selection of the installation location to the actual installation and commissioning, it is necessary to follow the requirements outlined in the product manual strictly. The installation location must be free from vibration and strong magnetic fields. During installation, it is necessary to ensure good contact between the transmitter and the pipeline, as well as proper grounding. The potential of the transmitter is at the same level as that of the fluid being measured. When in use, the gas remaining in the measurement tube must be completely expelled; otherwise, it will cause significant measurement errors. When an electromagnetic flowmeter is used to measure viscous liquids containing dirt, the viscosity or deposits adhere to the inner walls of the measurement tube or the electrodes, causing changes in the electrical potential output by the transmitter and resulting in measurement errors. If the amount of dirt on the electrodes reaches a certain thickness, it may prevent the instrument from functioning properly. Scaling or wear in the water supply pipes, which alters the inner diameter, will affect the intended flow rate and lead to measurement errors. For a gauge with a 100 mm diameter, a change of 1 mm in the inner diameter results in an additional error of about 2%. The measurement signal from the transmitter is a very small potential signal in the millivolt range; in addition to the flow rate signal, it also contains various signals that are not related to flow rate, such as the in-phase voltage, quadrature voltage, and common-mode voltage. To accurately measure flow rate, it is necessary to eliminate various interference signals and effectively amplify the flow signal. The performance of the converters for sewage flow meters should be improved; it is preferable to use microprocessor-based converters to control the excitation voltage. By selecting the excitation method and frequency based on the properties of the fluid being measured, it is possible to eliminate in-phase and orthogonal interference. However, the improved gauge structure is complex and costly. For more information, please visit the company’s official website at http://www.yb1518.com/. Please keep this link when reproducing the content!