Operating principle
Page 5
SGN-UM-00282-EN-05
June 2021
OPERATING PRINCIPLE
Fluid passing through the turbine causes the rotor to spin at a speed proportional
to the fluid velocity As each rotor blade passes through the magnetic field, the
blade generates an AC voltage pulse in the pickup coil at the base of the magnetic
pickup (see
) These pulses produce an output frequency proportional
to the volumetric flow through the meter The output frequency with further
processing represents flow rate and/or totalization of fluid passing through the
flow meter
The K-factor scaler input amplifier modifies the signal generated by the turbine
The amplifier sends the modified signal to an onboard microcontroller, which
counts pulses up to a predetermined number controlled by the K-factor value The
range of the K-factor is 1…999,999,999 The predetermined value, once reached,
triggers a pulse from the output circuitry
The K-factor is user adjustable through the programming interface The duration
of the output pulse is also selectable At the end of the output pulse, the internal
counters reset to zero and the process starts over
Turbine Rotor
Magnetic Pickup
or
Other Frequency
Output Device
Output
Signal
Figure 1: Schematic illustration of electric signal generated by rotor movement
