Measuring ranges
VX 570 English V1.10
Seite 15 von 44
7.5
Inlet / Outlet runs
In order to maintain the accuracy stipulated in the data sheets, the sensor must be inserted in the
center of a straight pip e section with an undisturbed flow progression.
An undisturbed flow progression is achieved if the sections in front of the sensor (inlet) and behind the
sensor (outlet) are sufficiently long, straight and without any obstructions such as edges, seams, curves
etc.
Therefore, it is necessary to ensure the recommended inlet and outlet runs.
Flow obstruction before the measurement section
Min length
Inlet run (L1))
Min length
Outlet run (L2))
Slight curve
(elbow < 90°)
15 x D
5 x D
Reduction
(Pipe narrows to the measurement section)
15 x D
5 x D
Expansion
(Pipe expands to the measurement section)
15 x D
5 x D
90° elbow or T-piece
25 x D
5 x D
2x elbow á 90°in einer Ebene
50 x D
5 x D
2x elbow á 90° 3-dimensional
50 x D
5 x D
Control valve
50 x D
5 x D
15 x D
5 x D
15 x D
5 x D
15 x D
25 x D
5 x D
50 x D
5 x D
50 x D
5 x D
5 x D
50 x D
The values represent the min. lengths. In case the min. inlet / outlet runs could not be ensured, it must
be expected to get increased or significant deviations of the measurement values
.
8
Commissioning
•
Depressurize the system
•
Ensure correct direction of flow during installation
•
Maintain an undisturbed flow course while observing the required calming distances in
the measuring range, see section 7.5