Endress+Hauser Proline Prosonic Flow W 400 Operating Instructions Manual page 23

Proline Prosonic Flow W 400 HART
D
2) Flow disturbance compensation
Endress+Hauser
The measured values of both sensor sets are averaged. Configuration of the measurement
is only performed once and is adopted for both measuring paths.
If extending the measuring point from single-path measurement to two-path
measurement, a sensor of the same design must be selected.
Two-path measurement with FlowDC
In the case of two-path measurement with FlowDC, the flow is measured by two
measurements at the measuring point.
For this, the two sensor sets are installed on the measuring pipe, offset at a specific angle
to one another (180° for 1 traverse, 90° for 2 traverses, angle tolerance ±5°). This
arrangement is independent of the circumferential position of the two sensor sets on the
measuring pipe.
The measured values of both sensor sets are averaged. The resulting measurement error is
compensated based on the type of interference, the distance from the measuring point to
the disturbance point, and the Reynolds number. The error-compensated average thus
ensures that the specified maximum measurement error and repeatability are maintained
even under non-ideal flow conditions (see for example →  20).
The configuration of the two measuring paths is only performed once and is adopted for
both measuring paths.
A
C
D
C
 6 Two-path measurement: examples of the horizontal arrangement of the sensor sets at a measuring point
A Installation of the sensor sets for measurement via 1 traverse
B Installation of the sensor sets for measurement via 2 traverses
C For horizontal orientation: non-recommended installation range (60°)
D For horizontal orientation: recommended installation range max. 120°
If no FlowDC is used, the specified inlet and outlet runs after disturbance points in the
measuring pipe (e.g. elbows, extensions, reductions) must be observed precisely to
obtain accurate flow measured values.
2)
B
C
D
C
Mounting procedure
D
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