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Reference Manual
00809-0300-4750, Rev CA
March 2016
Reading does
not appear to be
within rated
accuracy
•Transmitter, control system, or
other receiving device not
configured properly
•Check all configuration variables for the transmitter, sensor,
communicator, and/or control system
•Check these other transmitter settings:
•Sensor calibration number
•Units
•Line size
•Perform a loop test to check the integrity of the circuit
•Electrode Coating
•Enable Coated Electrode Detection diagnostic
•Use bullet-nose electrodes
•Downsize sensor to increase flow rate above 3 ft/s
•Periodically clean sensor
•Gas/air in line
•Move the sensor to another location in the process line to
ensure that it is full under all conditions
•Moisture problem
•Perform the sensor tests - see
•Insufficient
upstream/downstream pipe
diameter
•Move sensor to a new location with five pipe diameters
upstream and two pipe diameters downstream if possible
•Cables for multiple magmeters
run through same conduit
•Use dedicated conduit run for each sensor and transmitter
•Improper wiring
•If electrode shield and electrode signal wires are switched, flow
indication will be about half of what is expected. Check wiring
diagrams.
•Flow rate is below 1 ft/s
(specification issue)
•See accuracy specification for specific transmitter and sensor
•Auto zero was not performed
when the coil drive frequency
was changed from 5 Hz to 37 Hz
•Set the coil drive frequency to 37 Hz, verify the sensor is full,
verify there is no flow, and perform the auto zero function
•Sensor failure–shorted
electrode
•Perform the sensor tests - see
•Sensor failure–shorted or open
coil
•Perform the sensor tests - see
•Transmitter failure
•Verify transmitter operation with a Rosemount 8714
Calibration Standard or replace the electronics board
Table 9-7. Common Magmeter Issues
Symptom
Potential cause
Corrective action
Summary of Contents for Rosemount 8750W
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