Emerson MICRO MOTION 2700, Руководство по конфигурации и использованию, Страница: 249 / 374

Possible causes and recommended actions for low pickoff voltage
(continued)
Table 12-10:
Possible cause Recommended actions
No tube vibration in sensor • Check for plugging.
• Ensure sensor is free to vibrate (no mechanical binding).
• Verify wiring.
• Test coils at sensor. See Section 12.28.1 .
Moisture in the sensor elec-
tronics Eliminate the moisture in the sensor electronics.
The sensor is damaged, or
sensor magnets may have be-
come demagnetized Replace the sensor.
12.27.1 Collect pickoff voltage data
Pickoff voltage data can be used to diagnose a variety of process and equipment
conditions. Collect pickoff voltage data from a period of normal operation, and use this
data as a baseline for troubleshooting.
Procedure
1. Navigate to the pickoff voltage data.
2. Observe and record data for both the left pickoff and the right pickoff, over an
appropriate period of time, under a variety of process conditions.
12.28 Check for electrical shorts
Shorts between sensor terminals or between the sensor terminals and the sensor case can
cause the sensor to stop working.
Possible causes and recommended actions for electrical shorts Table 12-11:
Possible cause Recommended action
Moisture inside the junction box Ensure that the junction box is dry and no corrosion is
present.
Liquid or moisture inside the sensor
case Contact Micro Motion.
Internally shorted feedthrough Contact Micro Motion.
Faulty cable Replace the cable.
Improper wire termination Verify wire terminations inside sensor junction box. The
Micro Motion document titled
9-Wire Flowmeter Cable Prepa-
ration and Installation Guide may offer some assistance.
Troubleshooting
Configuration and Use Manual 241