Emerson Micro Motion 2500, Руководство по конфигурации и использованию

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Problem Possible causes Recommended actions
Unusually high densi-
ty reading • Plugged or coated sensor tube
• Incorrect density calibration factors
• Incorrect temperature measurement
• RTD problem
• In high-frequency meters, this can indicate
erosion or corrosion
• In low-frequency meters, this can indicate
tube fouling
• Ensure that all of the calibration parame-
ters have been entered correctly. See the
sensor tag or the calibration sheet for your
meter.
• Verify all of the characterization or calibra-
tion parameters. See the sensor tag or the
calibration sheet for your meter.
• Purge the sensor tubes.
• Check for coating in the flow tubes.
Unusually low density
reading • Two-phase flow
• Ensure that all of the calibration parame-
ters have been entered correctly. See the
sensor tag or the calibration sheet for your
meter.
• In low-frequency meters, this can indicate
erosion or corrosion
• Check your process conditions against the
values reported by the device.
• Check for two-phase flow.
• Verify all of the characterization or calibra-
tion parameters. See the sensor tag or the
calibration sheet for your meter.
• Check the wiring between the sensor and
the transmitter.
• Check for tube erosion, especially if the
process fluid is abrasive.
12.5 Temperature measurement problems
Problem Possible causes Recommended actions
Temperature reading
significantly different
from process temper-
ature • RTD failure
• Incorrect compensation factors
• Line temperature in bypass does not
match temperature in main line
• Check junction box for moisture or verdi-
gris.
• Perform RTD resistance checks and check
for shorts to case (see
Section 12.30.1 ).
• Verify that the temperature compensation
factors match the value on the sensor tag
or calibration sheet.
• If Alert A004, A016, or A017 is active, per-
form the actions recommended for that
alert.
Troubleshooting
Configuration and Use Manual 173