Check For Internal Electrical Problems - Emerson Micro Motion 5700 Configuration And Use Manual

Configuration and Use Manual
MMI-20029769
Excessive (saturated) drive gain
Table 17-3: Possible causes and recommended actions for excessive (saturated) drive gain
Possible cause
Bent sensor tube
Cracked sensor tube
Core processor or module
failure
Flow rate out of range
Open drive or pickoff
sensor coil
Over-pressurized tubes
Plugged sensor tube
Sensor case full of process
fluid
Sensor imbalance
Sensor tubes not
completely full
Two-phase flow
Vibrating element not free
to vibrate
Erratic drive gain
Table 17-4: Possible causes and recommended actions for erratic drive gain
Possible cause
Foreign material caught in sensor
tubes

17.17 Check for internal electrical problems

Shorts between sensor terminals or between the sensor terminals and the sensor case can cause the sensor to
stop working.
Possible cause
Moisture inside the sensor junction box
Liquid or moisture inside the sensor case
Internally shorted feedthrough
Configuration and Use Manual
Recommended actions
Check the pickoff voltages (see
zero (but neither is zero), the sensor tubes may be bent. The sensor will need to be
replaced.
Replace the sensor.
Contact customer support.
Ensure that the flow rate is within sensor limits.
Contact customer support.
Contact customer support.
Check the pickoff voltages (see
zero (but neither is zero), plugged tubes may be the source of your problem. Purge the
tubes. In extreme cases, you may need to replace the sensor.
Replace the sensor.
Contact customer support.
Correct process conditions so that the sensor tubes are full.
Check for two-phase flow. See
Ensure that the vibrating element is free to vibrate.
Recommended actions
• Purge the sensor tubes.
• Replace the sensor.
Check the pickoff voltage). If either of them are close to
Check the pickoff voltage). If either of them are close to
Check for two-phase flow (slug
Recommended action
Ensure that the junction box is dry and no corrosion is
present.
Contact customer support.
Contact customer support.
Troubleshooting
March 2019
flow).
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