Micro Motion CDM100M, Configuration And Use Manual

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Related information
Standard matrices for the concentration measurement application
Concentration measurement matrices available by order
Load a concentration matrix using ProLink III
10.11 Velocity measurement problems
Velocity measurement problems and recommended actions Table 10-4:
Problem Possible causes Recommended actions
Non-zero velocity
reading at no-flow
conditions or at zero
offset • Misaligned piping (especially in new instal-
lations)
• Open or leaking valve
• Incorrect sensor zero
• Zero the meter. See Section 2.4 .
• Check for open or leaking valves or seals.
• Check for mounting stress on the sensor
(e.g., sensor being used to support piping,
misaligned piping).
• Contact Micro Motion.
Erratic non-zero ve-
locity reading at no-
flow conditions • Leaking valve or seal
• Two-phase flow
• Plugged or coated sensor tube
• Incorrect sensor orientation
• Wiring problem
• Vibration in pipeline at rate close to sensor
tube frequency
• Damping value too low
• Mounting stress on sensor
• Verify that the sensor orientation is appro-
priate for your application (refer to the
sensor installation manual).
• Check the drive gain and the pickoff volt-
age. See
Section 10.24 and Section 10.25 .
• Purge the sensor tubes.
• Check for open or leaking valves or seals.
• Check for sources of vibration.
• Verify damping configuration.
• Verify that the measurement units are con-
figured correctly for your application.
• Check for two-phase flow. See
Section 10.23 .
• Check for radio frequency interference.
See
Section 10.20 .
• Contact Micro Motion.
Troubleshooting
Configuration and Use Manual 153