10 Troubleshooting
FLUXUS F60*
10.4 Application-specific problems
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UMFLUXUS_F60xV5-0EN, 2017-10-16
10.4
Application-specific problems
A fluid with a wrong sound speed was selected
If the selected sound speed in the fluid does not match the actual one, the transducer
distance can probably not be determined correctly.
The fluid sound speed is used to calculate the transducer distance and is therefore very
important for the transducer positioning. The sound speeds stored in the transmitter only
serve as an orientation.
The entered pipe roughness is not appropriate
Check the entered value. The pipe state should be considered.
Measurements on pipes made of porous materials (e.g., concrete or cast iron) are
only conditionally possible
Contact FLEXIM.
The pipe lining may cause problems during the measurement if it is not firmly
attached to the inner pipe wall or consists of acoustically absorbing material
Try to measure on a section of the pipe free from lining.
Highly viscous fluids strongly attenuate the ultrasonic signal
The measurement of fluids with a viscosity of > 1000 mm²/s is only conditionally possible.
A high concentration of gases or solids in the fluid scatter and absorb the
ultrasonic signal and thus attenuate the measuring signal
A measurement is impossible if the value is
≥
10 %. If the proportion is high, but < 10 %,
a measurement is only conditionally possible.
10.5
Significant deviations of the measured values
A fluid with a wrong sound speed was selected
If a fluid was selected whose sound speed does not match the actual one, the measuring
signal may be confused with the pipe wall signal.
The flow calculated on the basis of the wrong signal by the transmitter is very small or
fluctuates around zero.
There is gas in the pipe
If there is gas in the pipe, the measured flow will be too high because both, the liquid and
gas volume, are measured.
The defined upper limit of the flow velocity is too low
All measured flow velocities that are greater than the upper limit will be ignored and
marked as invalid. All quantities deviated from the flow velocity will also be indicated as
invalid. If several correct measured values are ignored, the totalizer values will be too
low.