For troubleshooting, check the process variables under both normal flow and tubes-full no-flow conditions.
Except for flow rate, you should see little or no change between flow and no-flow conditions. If you see a
significant difference, record the values and contact customer service for assistance.
Unusual values for process variables may indicate a variety of different problems. The following table lists
several possible problems and suggested remedies.
Table 15-3: Process variables problems and remedies
Symptom Cause Suggested remedy
Steady non-zero flow rate
under no-flow conditions
Misaligned piping
(especially in new installations)
Correct the piping.
Open or leaking valve Check or correct the valve mechanism.
Bad sensor zero Rezero the flow meter. See Zero the meter.
Erratic non-zero flow rate
under no-flow conditions
Leaking valve or seal Check pipeline
Slug flow See Check for two-phase flow (slug flow).
Plugged flow tube Check drive gain and tube frequency.
Purge the flow tubes.
Incorrect sensor orientation Sensor orientation must be appropriate to the
process fluid. See the installation manual for
your sensor.
Wiring problem Check the sensor circuitry. See Check for
internal electrical problems.
Vibration in pipeline at rate close to
sensor tube frequency
Check the environment and remove the
source of the vibration.
Damping value too low Check the configuration.
See the appropriate section:
• Configure Flow Damping
• Configure Density Damping
• Configure Temperature Damping
Mounting stress on sensor Check the sensor mounting to ensure:
• Sensor is not being used to support the
pipe
• Sensor is not being used to correct pipe
misalignment
• Sensor is not too heavy for pipe
Sensor cross-talk Check the environment for sensor with a
similiar (±0.5 Hz) tube frequency.
Erratic non-zero flow rate
when flow is steady
Slug flow See Check for two-phase flow (slug flow).
Damping value too low Check the configuration. See Characterize the
meter (if required).
Plugged flow tube Check drive gain and tube frequency.
Purge the flow tubes
Configuration and Use Manual Troubleshooting
MMI-20048166 April 2019
Configuration and Use Manual 199
To Next Page
Loading...
