Micro Motion CDM100M, Configuration And Use Manual

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Alert num-
ber
Alert title Possible cause Recommended actions
N/A Zero Calibration in
Progress A zero calibration is in progress. • No action required.
10.7 Density measurement problems
Density measurement problems and recommended actions Table 10-2:
Problem Possible causes Recommended actions
Erratic density reading • Normal process noise
• Two-phase flow
• Flow rate too high
• Contaminants or suspended solids in the
process fluid
• Vibration in the pipeline
• Erosion or corrosion
• Check your process conditions.
• Increase the density damping value.
• Reduce the flow rate.
• Check for two-phase flow. See
Section 10.23 .
• Ensure that line pressure or sample pres-
sure meets installation requirements.
• Increase back pressure to minimize bubble
formation.
• Minimize vibration in the pipeline.
• Install a flow control method (bypass, flow
chamber, expander, etc.).
• Perform Known Density Verification.
Inaccurate density
reading • Inaccurate temperature measurement
• Incorrect calibration factors
• Contaminants or suspended solids in the
process fluid
• Verify the temperature reading from the
RTD (on-board temperature sensor).
• Verify the temperature reading from the
external temperature device, if applicable.
• Verify or adjust the density offset and/or
the density meter factor.
• Increase the flow rate.
• Install a thermal insulation jacket.
• Verify the calibration factors.
• Perform Known Density Verification.
Density reading too
high • Plugged or coated flow tube
• Inaccurate temperature measurement
• Incorrect calibration factors
• Erosion or corrosion on the sensor tubes
• Purge the flow tubes.
• Check for coating on the flow tubes.
• Verify the temperature reading from the
RTD (on-board temperature sensor).
• Verify the temperature reading from the
external temperature device, if applicable.
Troubleshooting
Configuration and Use Manual 149