Emerson Series 3000 MVD Manuel D’Utilisation

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Configuration and Use Manual
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Dia
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nostics and 
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 – Mo
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 Model 
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Measure
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Chapter 22
Diagnostics and Troubleshooting
22.1
About this chapter
This chapter explains how to use the diagnostic software to troubleshoot alarm conditions. Diagnostic 
software includes:
Meter fingerprinting
Sensor simulation mode
The active alarm log
Alarm messages
The diagnostic monitor
This chapter also provides additional information on troubleshooting.
22.2
Checking process variables
Micro Motion suggests that you make a record of basic process variables under normal operating 
conditions. This will help you recognize when the process variables are unusually high or low. The 
meter fingerprinting feature (see Section 22.3) may be used to record the current levels of twelve 
process variables, and to view the recorded levels of these process variables at three other points of 
transmitter operation.
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 Micro Motion customer 
service for assistance.
Unusual values for process variables may indicate a variety of different problems. Table 22-1 lists 
several possible problems and remedies.
Table 22-1
Process variables problems and possible remedies
Symptom
Cause
Possible 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 flowmeter. See 
Section 16.3.
Inappropriate measurement unit
Check configuration. See 
Section 22.13.
Cutoff set too low
Check configuration. See Section 7.3.2.
Bad flow calibration factor
Verify characterization. See 
Section 22.16.