Frequency Output Problems; Check Frequency Output Fault Action - Emerson Micro Motion 9739 MVD Configuration And Use Manual

Configuration and Use Manual
MMI-20016855

10.8 Frequency Output problems

Table 10-5: Frequency Output problems and recommended actions
Problem Possible causes
No Frequency Output •
•
•
•
•
•
•
•
•
Consistently incorrect •
frequency
•
measurement
Erratic Frequency •
Output

10.9 Check Frequency Output Fault Action

The Frequency Output Fault Action controls the behavior of the Frequency Output if the transmitter
encounters an internal fault condition. If the Frequency Output is reporting a constant value, the transmitter
may be in a fault condition.
Procedure
1. Check the status alerts for active fault conditions.
2. If there are active fault conditions, the transmitter is performing correctly. If you want to change its
behavior, consider the following options:
• Change the setting of Frequency Output Fault Action.
For the relevant status alerts, change the setting of Alert Severity to Ignore.
•
Restriction
For some status alerts, Alert Severity is not configurable.
3. If there are no active fault conditions, continue troubleshooting.
Configuration and Use Manual
Stopped totalizer
Process condition below cutoff
Fault condition if Fault Action is set to
Internal Zero or Downscale
Two-phase flow
Flow in reverse direction from configured
flow direction parameter
Bad frequency receiving device
Output level not compatible with receiving
device
Bad output circuit (rarely occurs)
Wiring problem
Output not scaled correctly
Incorrect measurement unit configured for
process variable
Radio frequency interference (RFI) from
environment
Recommended actions
• Verify that the process conditions are
below the low-flow cutoff. Reconfigure the
low-flow cutoff if necessary.
• Check the Fault Action settings.
• Verify that the totalizers are not stopped. A
stopped totalizer will cause the Frequency
Output to be locked.
• Check for two-phase flow.
• Check flow direction.
• Verify the receiving device, and the wiring
between the transmitter and the receiving
device.
• Verify that the channel is wired and
configured as a Frequency Output.
• Verify the power configuration for the
Frequency Output (internal vs. external).
• Perform a loop test.
• Check the Frequency Output scaling.
• Verify that the measurement units are
configured correctly for your application.
• Check for radio frequency interference.
Troubleshooting
June 2019
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