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Generally, in order to determine the flow value or the accuracy of the flow measurement value of the electromagnetic flowmeter at the user site, the electromagnetic flowmeter must be calibrated. Calibration is sometimes called calibration or verification. In fact, calibration includes two aspects: ①Transfer the value to the instrument to determine the location of the flow scale mark (or determine the signal output by the flow scale) ； ②The output of the adjusted instrument is compared with the standard value (reference value) to determine the accuracy of the instrument and determine its error value. Calibration of flow value transfer properties in the previous electromagnetic flowmeter industry * Customary flow "calibration", within the hydrology and water industry * It is called "calibration", and the calibration process by which the user determines the accuracy of the instrument is called flow "checking". These names are now becoming consistent and "calibration" is used instead. * * The authorized flow laboratory is also named "Flow Calibration Laboratory". There are two methods for flow calibration of electromagnetic flowmeter: direct measurement method and indirect measurement method. The direct measurement method, also known as the real flow calibration method, uses the actual fluid to flow through the instrument to be calibrated, and then uses other standard devices (standard flow meters or flow standard measuring instruments) to measure the flow rate of the fluid, and compares it with the flow value of the instrument to be calibrated. This method is called wet calibration. The flow value obtained by the real flow calibration method is both reliable and accurate. It is currently used by many flow meters (such as electromagnetic flowmeter, volumetric flowmeter, turbine flowmeter, Coriolis mass flowmeter) and is used as a method to establish standard flow rate. Before the electromagnetic flowmeter leaves the factory, the manufacturer uses the real flow calibration method to complete the flow value transfer process on the flow calibration standard device (sometimes referred to as the flow standard device or flow calibration device). The user unit must also conduct real-flow calibration on the flow calibration standard device for the instruments after regular verification and maintenance. HD-LDE electromagnetic flowmeter flow calibration standard device is established in accordance with relevant standards and verification regulations, and is * * Authorized specialized agencies have determined that devices capable of transmitting flow values are calibration equipment that provide flow values, and their values can be traced to quality, time and temperature. * * Measurement base quantity. Dry calibration is an indirect calibration method that measures the flow area and other structural dimensions of the electromagnetic flow sensor and the magnetic flux density B, calculates the flow value, and obtains the corresponding accuracy. Dry calibration was a calibration method developed in the 1970s to solve the problem of the inability to achieve real flow calibration of large-diameter electromagnetic flowmeters. It was once included in the Japanese Industrial Standard JIS Z8764-1975 "Method of measuring flow rate using electromagnetic flowmeter". Due to its relatively low accuracy, it is rarely used today. The content of dry calibration in the Japanese Industrial Standard JIS Z 8764 "Electromagnetic Flowmeter" revised in 1986 is no longer part of the main text, but has been moved to the explanation part (equivalent to the appendix and preparation instructions of our country's standards). On-site "flow comparison" means that the electromagnetic flowmeter is compared with other "reference flows" on site. For example, the measurement value of the temporarily installed ultrasonic flow separation machine, the measured volume of liquid flowing into the pipeline system, etc. can be used as the "reference flow rate". “"Flow comparison" is only a auxiliary check to evaluate the measurement value of the electromagnetic flowmeter, the general error range, and to determine whether the instrument is normal or faulty. For more information, please visit the company’s official website http://www.yb1518.com/. Please keep this link when reprinting! http://www.yb1518.com/UploadFiles/2012717174126829.jpg