10.4 Density measurement problems
Density measurement problems and recommended actionsTable 10-4:
Problem Possible causes Recommended actions
Inaccurate density
reading
• Problem with process fluid
• Incorrect density calibration factors
• Wiring problem
• Incorrect flowmeter grounding
• Slug flow
• Plugged or coated flow tube
• Incorrect sensor orientation
• RTD failure
• Physical characteristics of sensor have
changed
• Check the wiring between the sensor and
transmitter. See Section 10.10.
• Check grounding. See Section 10.11.
• Check your process conditions against the
values reported by the flowmeter.
• Verify that all of the characterization parame-
ters match the data on the sensor tag.
• Check for slug flow. See Section 10.25.
• If two sensors with similar frequency are too
near each other, separate them.
• Purge the flow tubes.
Unusually high densi-
ty reading
• Plugged or coated flow tube
• Incorrect K2 value
• Incorrect temperature measurement
• RTD problem
• In high frequency meters, this can be an
indication of erosion or corrosion
• In low frequency meters this can indi-
cate tube fouling
• Verify that all of the characterization parame-
ters match the data on the sensor tag.
• Purge the flow tubes.
• Check for coating in the flow tubes.
Unusually low density
reading
• Slug flow
• Incorrect K2 value
• In low frequency meters this can indi-
cate erosion or corrosion
• Check your process conditions against the
values reported by the flowmeter.
• Verify that all of the characterization parame-
ters match the data on the sensor tag.
• Check the wiring between the sensor and
transmitter. See Section 10.10.
• Check for tube erosion, especially if the proc-
ess fluid is abrasive.
Troubleshooting
188 Micro Motion
®
Model 1700 Transmitters with Analog Outputs