Emerson MMI-20019043 Satellite Radio User Manual


 
12.4 Density measurement problems
Density measurement problems and recommended actionsTable 12-4:
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 12.10.
Check grounding. See Section 12.11.
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 12.25.
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 12.10.
Check for tube erosion, especially if the proc-
ess fluid is abrasive.
Troubleshooting
222 Micro Motion
®
Model 2700 Transmitters with Analog Outputs