Siemens SITRANS LR110 Operating Instructions Manual page 25

Installing/mounting
4.4 Measurement setup - Flow
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Channel with dimensions according to ISO standard:
When selecting these curves, the dimensions of the flume must be known and
entered via the assistant. As a result, the accuracy of the flow measurement is higher
than with the specified curves.
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Flow formula:
If the flow formula of your flume is known, you should select this option, as the
accuracy of the flow measurement is highest here.
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Manufacturer definition:
If you use a Parshall flume from the manufacturer ISCO, this option must be selected.
This gives you a high accuracy of flow measurement with easy configuration.
Alternatively, you can also take over Q/h table values provided by the manufacturer
here.
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Note
Detailed project planning data can be found at the channel manufacturers and in the
technical literature.
The following examples serve as an overview for flow measurement.
18
Venturi, trapezoidal weir, rectangular flume (Q = k x h
V-Notch, triangular overfall (Q = k x h
Rectangular flume (ISO 4359)
Trapezoidal flume (ISO 4359)
U-shaped flume (ISO 4359)
Triangular overfall thin-walled (ISO 1438)
Rectangular flume thin-walled (ISO 1438)
Rectangular weir broad crown (ISO 3846)
Flow formula: Q = k x h
ISCO-Parshall-Flume
Q/h table (assignment of height with corresponding flow in a table)
2.5
)
exp
1.5
)
SITRANS LR110, HART
Operating Instructions, 10/2023, A5E49829006