There are big differences in the performance of general-purpose electromagnetic flowmeter on the market. Some have high accuracy and many functions, and some have low accuracy and simple functions.
The typical accuracy of a magnetic flowmeter is 0.5% of the measured value from 0.3 ft per sec to 33 ft per sec (0.1 to 10 m per sec) velocity. Some suppliers indicate even higher accuracy over portions of the flow range, up to 0.1% of the indicated flow rate.
However, this high accuracy has strict installation requirements and reference conditions. For example, the ambient temperature is 20-22℃, and the length of the front and rear straight pipes are required to be greater than 10D, 3D (usually 5D, 2D). It is even proposed that the flow sensor should be integrated with the front and rear straight pipes. Perform real flow calibration on the flow standard device to reduce the impact of improper clamping.