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I. Classification by the assembly method of sensors and converters 1. Split-type electromagnetic flowmeters – The split-type is the most commonly used form of electromagnetic flowmeters; the sensor is installed within the pipeline, while the converter is placed in a control room or near the sensor where it is easily accessible, at a distance of several dozen to several hundred meters. To prevent external noise from intruding, signal cables typically use double shielding. When measuring liquids with low conductivity at distances of over 30 m, in order to prevent signal attenuation caused by the capacitance of the cables, it is also necessary for the inner shielding to be connected to a low-impedance source at the same potential as the core wire, via a shielding drive. The separate converter can be placed away from the harsh conditions at the site, making it easier to inspect the electronic components, make adjustments, and set parameters. 2. Integrated electromagnetic flowmeter – The sensor and converter are combined together to directly output a standard DC current (or frequency) signal, effectively functioning as an electromagnetic flow transmitter. The integrated design reduces the length of the connection wires between the two, as well as those for excitation, allowing them to be external connections hidden inside the instrument; this helps to minimize signal attenuation and the intrusion of spatial electromagnetic noise. The same measurement circuit can measure liquids with lower conductivity compared to the split-type version. The wiring for signal lines and excitation wires has been eliminated, simplifying the electrical connections; as a result, the cost of the instruments as well as the installation costs are relatively low, making them suitable for use in instruments with small diameters. With the commercialization of two-wire instruments, integrated instruments are expected to develop rapidly. However, if it is installed in a location that is difficult to access due to piping layout constraints, maintenance becomes inconvenient. Furthermore, the electronic components of the converter, being mounted on the pipeline, are subject to significant constraints due to fluid temperature and pipe vibrations. II. Classification by the connection method between the flow sensor and the pipeline 1. Electromagnetic flowmeter with flange connection – Flange connection is a traditional method; the sensor has flanges at both ends, which are secured to the pipeline flanges using bolts, allowing for installation in one direction only. Large-diameter sensors all use this connection method. It is larger in both volume and weight compared to the clamped connection method. The length between the two flange faces of DN15～600mm electromagnetic flowmeters has been standardized by the International Organization for Standardization (ISO13359;1998) to ensure consistency. 2. Flange-clamped connection for electromagnetic flowmeters – This is a connection method that has been developed in recent years; the sensor itself does not have flanges, and it is held between the flanges of the pipeline using long bolts to be integrated into the piping system. This type of sensor is small in size and light in weight, and it has strong adaptability to different pressure specifications as well as to the flange spacing in standard piping systems ； But it is only applicable to smaller pipe diameters (below 200mm) and can withstand lower liquid working pressures. 3. Clamp-connected electromagnetic flowmeter – The clamp connection allows for quick disassembly and installation, facilitating frequent cleaning on a daily basis. 4. Threaded electromagnetic flowmeters – These types of instruments are widely used in industries such as pharmaceuticals and food, as well as in applications involving the precise dosing of substances in the pharmaceutical sector. Threaded connections are also widely used in industries such as petroleum and geological exploration for measuring the flow rate of high-pressure water injection or cement slurry at pressures above 16–25 MPa, with a trapezoidal thread shape. 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