RMG ERZ2000-NG, Operating Manual

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6 Flow meters
Manual ERZ 2000-NG · EN07 · 2019, May 13th
203
6.2 Turbine meter
The operating method of turbine meters is based on the measurement of gas speed
with a turbine wheel. In the process, the speed of the turbine (approximately) within
the measuring range (Q
min
- Q
max
) is proportional to the mean gas speed and thus
the flow rate. The number of rotations, therefore, is a measurement for the gas vol-
ume flowing through.
Figure 138: Turbine meter sectional drawing
The rotational movement of the turbine wheel is transferred after reduction to the me-
ter head in which the frequency is normally scanned redundantly with two sensors
and transmitted as a LF signal. The meter can be optionally equipped with an encod-
er that can also transmit flow information.
In principle, the further processing of low-frequency pulses independently of the
measuring principle, can also be handled in a comparable manner by rotary piston
gas meters, vortex meters or other flow measuring devices with a frequency output.