The working principle of the pulse flow meter:

A turbine is placed in the center of the pipe, and both ends are supported by bearings. When the fluid passes through the pipe, it impacts the turbine blades and generates a driving torque on the turbine, causing the turbine to overcome the friction torque and fluid resistance torque and rotate. Within a certain flow range and for a certain fluid medium viscosity, the rotation angular speed of the turbine is proportional to the fluid flow rate. Therefore, the fluid flow velocity can be obtained from the rotation angular velocity of the turbine, so that the fluid flow rate through the pipe can be calculated.

The rotation speed of the turbine is detected by a sensing coil installed outside the casing. When the turbine blades cut the magnetic lines of force generated by the permanent magnets in the housing, it will cause changes in the magnetic flux in the sensing coil. The sensing coil sends the detected magnetic flux periodic change signal to the preamplifier, which amplifies and shapes the signal to generate a pulse signal proportional to the flow rate, which is sent to the unit conversion and flow accumulation circuit to obtain and display the cumulative flow value; At the same time, the pulse signal is also sent to the frequency current conversion circuit to convert the pulse signal into an analog current amount, thereby indicating the instantaneous flow value.

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