10 Troubleshooting
FLUXUS G722ST-HT
10.1 Problems with the measurement
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UMFLUXUS_G722ST-HTV1-2EN, 2021-09-01
10.1
Problems with the measurement
A measurement is not possible because no signal is received. An interrogation point is displayed after the
physical quantity. The LED lights red after starting the measurement.
• Check whether the entered parameters are correct, especially the outer pipe diameter, the pipe wall thickness and the
sound speed of the fluid. Typical errors: The circumference or the radius was entered instead of the diameter. The inner
pipe diameter was entered instead of the outer pipe diameter.
• Make sure that the recommended transducer distance was adjusted when mounting the transducers.
• Make sure that an appropriate measuring point is selected.
• Try to establish a better acoustic contact between the pipe and the transducers.
• Make sure that the expected max. flow was entered correctly.
The measuring signal is received but no measured values can be obtained.
• If the defined upper limit of the flow velocity is exceeded or the lower limit is below,
UNDEF
and after the physical quantity
an exclamation point will be displayed. The measured values are marked as invalid. The limit has to be adapted to the
measuring conditions.
• If no exclamation point is displayed, a measurement at the selected measuring point is impossible.
The signal is lost during the measurement.
• If the pipe was without any pressure and afterwards no measuring signal has been received, contact FLEXIM.
• Wait a moment until the acoustic contact is reestablished. The measurement can be interrupted by a temporarily high
portion of liquid and solids in the fluid.
The measured values substantially differ from the expected values.
• Wrong measured values are often caused by wrong parameters. Make sure that the parameters entered for the
measuring point are correct.
10.2
Measuring point selection
• Make sure that the recommended min. distance to any disturbance is observed.
• Avoid measuring points with deposit formation in the pipe.
• Avoid measuring points in the vicinity of deformations and defects on the pipe as well as welds.
• Make sure the pipe surface at the selected measuring point is even.
• Measure the temperature at the measuring point and make sure that the transducers are suitable for this temperature.
• Make sure that the outer pipe diameter is within the measuring range of the transducers.
• When measuring on a horizontal pipe, the transducers have to be mounted laterally on the pipe.
10.3
Maximum acoustic contact
• see section 6.2
10.4
Application-specific problems
The entered pipe roughness is not appropriate.
• Check the entered value considering the pipe condition.
The pipe lining may cause problems during the measurement if it is not firmly attached to the inner pipe wall or
consists of an acoustically absorbing material.
• Try to measure on a section of the pipe free from lining.
