Troubleshooting

If slug flow occurs:

Check the process for cavitation, flashing, or leaks.

Change the sensor orientation.

Monitor density.

If desired, enter new slug flow limits (see Section 8.7).

-Raising the low slug flow limit or lowering the high slug flow limit will increase the possibility of slug flow conditions.

-Lowering the low slug flow limit or raising the high slug flow limit will decrease the possibility of slug flow conditions.

If desired, increase slug duration (see Section 8.7).

11.15Checking the sensor tubes

Corrosion, erosion, or damage to the sensor tubes can affect process measurement. To check for these conditions, perform the meter verification procedure. See Chapter 10.

11.16Checking the flow measurement configuration

Using an incorrect flow measurement unit can cause the transmitter to report unexpected process variable values, with unpredictable effects on the process. Make sure that the configured flow measurement unit is correct. Check the abbreviations; for example, g/min represents grams per minute, not gallons per minute. See Section 6.3.

11.17Checking the characterization

A transmitter that is incorrectly characterized for its sensor might report inaccurate process variable values. Both the K1 and Flow Cal (FCF) values must be appropriate for the sensor. If these values are incorrect, the sensor may not drive correctly or may send inaccurate process data.

If you discover that any of the characterization data are wrong, perform a complete characterization. See Section 6.2.

11.18Checking the calibration

Improper calibration can cause the transmitter to report unexpected process variable values. If the transmitter appears to be operating correctly but sends unexpected process variable values, an improper calibration may be the cause.

Micro Motion calibrates every transmitter at the factory. Therefore, you should suspect improper calibration only if the transmitter has been calibrated after it was shipped from the factory. Before performing a calibration, consider meter validation or meter verification and select the appropriate procedure (see Section 10.2). Contact Micro Motion customer service for assistance.

11.19Checking the test points

Some status alarms that indicate a sensor failure or overrange condition can be caused by problems other than a failed sensor. You can diagnose sensor failure or overrange status alarms by checking the flowmeter test points. The test points include left and right pickoff voltages, drive gain, and tube frequency. These values describe the current operation of the sensor.

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Emerson Process Management 2400S manual Checking the sensor tubes, Checking the flow measurement configuration