Emerson Micro Motion 2500, Руководство по конфигурации и использованию

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To know whether your drive gain is excessive or erratic, you must collect drive gain data
during the problem condition and compare it to drive gain data from a period of normal
operation.
Excessive (saturated) drive gain
Possible causes and recommended actions for excessive (saturated)
drive gain
Table 12-4:
Possible cause Recommended actions
Bent sensor tube Check the pickoff voltages (see Section 12.29 ). If either of them are close to
zero (but neither is zero), the sensor tubes may be bent. The sensor will
need to be replaced.
Cavitation or flash-
ing; settling of two-
phase or three-phase
fluids • Increase the inlet or back pressure at the sensor.
• If a pump is located upstream from the sensor, increase the distance
between the pump and sensor.
• The sensor may need to be reoriented or repositioned. Consult the in-
stallation manual for your sensor.
Cracked sensor tube Replace the sensor.
Core processor
or module failure Contact customer support.
Flow rate out of
range Ensure that the flow rate is within sensor limits.
Incorrect sensor
characterization Verify the characterization or calibration parameters.
Open drive or pickoff
sensor coil Contact customer support.
Over-pressurized
tubes Contact customer support.
Plugged sensor tube Check the pickoff voltages (see Section 12.29 ). If either of them are close to
zero (but neither is zero), plugged tubes may be the source of your prob-
lem. Purge the tubes. In extreme cases, you may need to replace the sen-
sor.
Sensor case full
of process fluid Replace the sensor.
Sensor imbalance Contact customer support.
Sensor tubes
not completely full Correct process conditions so that the sensor tubes are full.
Two-phase flow Check for two-phase flow. See Section 12.27 .
Vibrating element
not free to vibrate Ensure that the vibrating element is free to vibrate.
Troubleshooting
Configuration and Use Manual 189