Diagnosing Wiring Problems - Emerson Micro-Motion 2400S Configuration And Use Manual

Troubleshooting
Table 11-5 Process variables problems and remedies continued
Symptom
Inaccurate density reading
Temperature reading significantly
different from process temperature
Temperature reading slightly different
from process temperature
Unusually high density reading
Unusually low density reading
Unusually high tube frequency
Unusually low tube frequency
Unusually low pickoff voltages
Unusually high drive gain

11.14 Diagnosing wiring problems

Use the procedures in this section to check the transmitter installation for wiring problems.
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Cause
Problem with process fluid
Bad density calibration factors
Wiring problem
Bad flowmeter grounding
Slug flow
Sensor cross-talk
Plugged flow tube
Incorrect sensor orientation
RTD failure
Physical characteristics of sensor have
changed
RTD failure
Sensor leaking heat
Plugged flow tube
Incorrect K2 value
Slug flow
Incorrect K2 value
Sensor erosion
Plugged flow tube, corrosion, or erosion
Several possible causes
Several possible causes
Micro Motion
Suggested remedy
• Use standard procedures to check
quality of process fluid.
• Verify characterization. See
Section 6.2.
• Check the sensor circuitry. See
Section 11.25.
• See Section 11.14.2.
• See Section 11.17.
• Check environment for sensor with
similar (±0.5 Hz) tube frequency.
• Check drive gain and tube frequency.
Purge the flow tubes.
• Sensor orientation must be
appropriate to process fluid. See the
installation manual for your sensor.
• Check for alarm conditions and follow
troubleshooting procedure for
indicated alarm.
• Check for corrosion, erosion, or tube
damage. See Section 11.18.
• Check for alarm conditions and follow
troubleshooting procedure for
indicated alarm.
• Verify "Use external temperature"
configuration and disable if
appropriate. See Section 9.3.
• Insulate the sensor.
• Check drive gain and tube frequency.
Purge the flow tubes.
• Verify characterization. See
Section 6.2.
• See Section 11.17.
• Verify characterization. See
Section 6.2.
• Contact Micro Motion. See
Section 11.3.
• Purge the flow tubes.
• Perform meter verification. See
Section 11.18.
• See Section 11.24.4
• See Section 11.24.3.
®
Model 2400S Transmitters with Analog Outputs
.