Flexim FLUXUS H721 User Manual

13 User modes
13.2 ExpertUser mode FLUXUS H721
2022-05-15, UMFLUXUS_H721V1-5EN
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13.2.3 Pipe signal detection
When evaluating the plausibility of the signal, it is checked whether the sound speed is within a defined range. The
absolute threshold of the fluid sound speed used is calculated from the greatest of the following values:
• absolute threshold, default value: 1848 m/s
• value of the sound speed curve of the fluid at the operating point plus relative threshold, default relative threshold:
200 m/s
• Select the menu item Special settings in the program branch Options.
• Press ENTER until the menu item Pipe signal detection is displayed.
•Select Off to measure without pipe signal detection.
•Select Default if no customized inputs are to be made and the default values are to be used.
•Select Customized to define the values of the pipe signal detection.
• Press ENTER.
• Enter the value of the absolute threshold for the particular measuring channel.
• Press ENTER.
• Enter the value for the relative threshold for the particular measuring channel.
• Press ENTER.
13.2.4 Profile correction
It is possible to select the following versions for the calculation of the fluid mechanic calibration factor k
Re
:
• kRe 1.0: profile correction (previous version)
• kRe 2.0: improved profile correction (current version, default)
• kRe 2.0 disturb. corr.: improved profile correction at non ideal inflow conditions for the positive flow direction
(negative flow direction without disturbance correction)
• kRe 2.0 dist.corr.bidir.: improved profile correction at non ideal inflow conditions for the positive and negative
flow direction (automatic toggling of the profile correction depending on the flow direction)
The following steps are necessary to set the profile correction:
• selection of the profile correction version for all measuring channels in the program branch Special functions.
• selection of the disturbance type in the program branch Parameters
• input of the disturbance distance in the program branch Parameters if kRe 2.0 disturb. corr. or kRe 2.0
dist.corr.bidir. has been selected
Options\Special settings\Pipe signal detection
Options\Special settings\Absolute threshold
Options\Special settings\Relative threshold
Example
absolute threshold: 2007 m/s
relative threshold: 600 m/s
value of the sound speed curve at the measuring point: 1546 m/s
As 1546 m/s + 600 m/s = 2146 m/s is greater than the absolute value 2007 m/s, this value will be used as the absolute
limit of the sound speed when the plausibility of the signal is evaluated.
Notice!
If kRe 2.0 disturb. corr. or kRe 2.0 dist.corr.bidir. has been selected, the transducers have to be
mounted in reflection arrangement, X arrangement or displaced X arrangement to compensate cross-flow effects.

Flexim FLUXUS H721 Specifications

General

Brand	Flexim
Model	FLUXUS H721
Category	Measuring Instruments
Language	English