Emerson Model 1700 用户手册
10.3
Flow measurement problems
Flow measurement problems and recommended actions
Table 10-3:
Problem
Possible causes
Recommended actions
Flow indication at no
flow conditions or
zero offset
flow conditions or
zero offset
•
Misaligned piping (especially in new in-
stallations)
stallations)
•
Open or leaking valve
•
Incorrect sensor zero
•
Verify that all of the characterization parame-
ters match the data on the sensor tag.
ters match the data on the sensor tag.
•
If the flow reading is not excessively high, re-
view the live zero. You may need to restore
the factory zero.
view the live zero. You may need to restore
the factory zero.
•
Check for open or leaking valves or seals.
•
Check for mounting stress on the sensor
(e.g., sensor being used to support piping,
misaligned piping).
(e.g., sensor being used to support piping,
misaligned piping).
•
Contact Micro Motion.
Erratic non-zero flow
rate under no-flow
conditions
rate under no-flow
conditions
•
Leaking valve or seal
•
Slug flow
•
Plugged or coated flow tube
•
Incorrect sensor orientation
•
Wiring problem
•
Vibration in pipeline at rate close to sen-
sor tube frequency
sor tube frequency
•
Damping value too low
•
Mounting stress on sensor
•
Verify that the sensor orientation is appropri-
ate for your application (refer to the sensor
installation manual).
ate for your application (refer to the sensor
installation manual).
•
Check the drive gain and the pickoff voltage.
See
See
•
If the wiring between the sensor and the
transmitter includes a 9-wire segment, verify
that the 9-wire cable shields are correctly
grounded.
transmitter includes a 9-wire segment, verify
that the 9-wire cable shields are correctly
grounded.
•
Check the wiring between the sensor and
transmitter. See
transmitter. See
.
•
For sensors with a junction box, check for
moisture in the junction box.
moisture in the junction box.
•
Purge the flow tubes.
•
Check for open or leaking valves or seals.
•
Check for sources of vibration.
•
Verify damping configuration.
•
Verify that the measurement units are con-
figured correctly for your application.
figured correctly for your application.
•
Check for slug flow. See
•
Check for radio frequency interference. See
.
•
Contact Micro Motion.
Troubleshooting
186
Micro Motion
®
Model 1700 Transmitters with Analog Outputs