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When an electromagnetic flowmeter is operated at a higher excitation frequency, it can respond quickly to changes in flow rate; thus, it is capable of measuring such flow rates. It is commonly used to measure the outlet flow rate of reciprocating pumps, diaphragm pumps, and similar devices. Electromagnetic flowmeters used for dynamic flow measurement typically require special design in the following three aspects, and proper calibration is necessary when they are put into operation. 1. The excitation frequency is adjustable to obtain an excitation frequency that matches the dynamic frequency. Both too high and too low levels are unfavorable. 2. The analog signal processing section of the electromagnetic flowmeter should prevent saturation when peak values occur. The peak value of the flowing current can sometimes be surprising; if, at the time when this peak occurs, the input channel for the flow signal of the electromagnetic flowmeter becomes saturated, it is as though the peak has been eliminated, which will inevitably result in a lower reading on the instrument. 3. To read the average value, the display area should be smoothed. Since the measuring part of the electromagnetic flowmeter can respond quickly to changes in the flowing flow rate and accurately reflect the actual flow rate, if the display part also showed the actual flow value exactly, it would inevitably cause large fluctuations in the displayed value, making it difficult to read. Therefore, the display should show the average value over a certain period of time. The implementation method usually involves inserting an inertial element; once an appropriate time constant is selected, the instrument can display values stably. However, if the time constant is chosen too large, the display will respond slowly when the average flow rate changes, creating an illusion in observation. There are three methods for measuring dynamic flow: a. Using an electromagnetic flowmeter with a fast response time ； b. Use an appropriate method to reduce the dynamic attenuation to a sufficiently small amplitude, and then perform the measurement using a regular flow meter ； c. Perform error correction on the flow rate values measured under dynamic flow conditions. . In some systems, both the b and c methods need to be combined in order to carry out measurements. This is because the amplitude of the motion is high, exceeding the range for which the estimation formulas apply; if only the damping method is used, the amplitude after attenuation does not fall within the range of a stable flow. 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