Flexim FLUXUS G801 - Upper Limit of the Sound Speed; Detection of Long Measurement Failures

17 SuperUser mode
FLUXUS G801 17.5 Upper limit of the sound speed
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UMFLUXUS_G801V1-0EN, 2020-06-26
17.5 Upper limit of the sound speed
When evaluating the plausibility of the signal, it is checked whether the sound speed is within a defined range. The upper
limit of the fluid sound speed used for this purpose is the greater of the following values:
• fixed upper limit, default: 1848 m/s
• value of the sound speed curve of the fluid at the operating point plus offset; default offset: 300 m/s
In the SuperUser mode, the values can be defined for fluids that are not contained in the data set of the transmitter.
• Select the menu item Miscellaneous.
• Press ENTER until the menu item Bad soundspeed is displayed.
• Enter the fixed upper limit of the sound speed for each measuring channel. Enter zero to use the default value of 1848 m/s.
• Press ENTER.
• Enter the offset for each measuring channel. Enter zero to use the default value of 300 m/s.
• Press ENTER.
It is possible to display the valid range of the sound speed (SS) in the lower line in the program branch Measuring.
The second value (here: 2146 m/s) corresponds to the upper limit at the operating point.
17.6 Detection of long measurement failures
If there are no valid measured values during a long time interval, new increments of the totalizers will be ignored.
The values of the totalizers remain unchanged.
In the SuperUser mode, it is possible to set the time interval.
• Select the menu item Miscellaneous.
• Press ENTER until the menu item Do not total. if no meas. is displayed.
• Enter the time. If zero is entered, the default value of 30 s will be used.
• Press ENTER.
Special Funct.\SYSTEM settings\Measuring\Miscellaneous\Bad soundspeed
Special Funct.\SYSTEM settings\Measuring\Miscellaneous\Bad soundspeed\thresh.
Special Funct.\SYSTEM settings\Measuring\Miscellaneous\Bad soundspeed\offset
Example
fixed upper limit of the sound speed (thresh.): 2007 m/s
offset: 600 m/s
value of the sound speed curve at the operating point: 1546 m/s
As 1546 m/s + 600 m/s = 2146 m/s is above the fixed upper limit of 2007 m/s, it will be used as the upper limit of the
sound speed when evaluating the plausibility of the signal.
Fig. 17.1: Display of the valid sound speed range
Notice!
The defined upper limit of the sound speed remains activated after the deactivation of the SuperUser mode.
Special Funct.\SYSTEM settings\Measuring\Miscellaneous\Do not total. if no meas.
GAIN=91dB
SS=1038/2146 m/s