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Reference Manual
00809-0100-4665, Rev AA
August 2010
6-5
Rosemount 8732
TRANSMITTER
TROUBLESHOOTING
Table 6-4. Advanced Troubleshooting–Rosemount 8732
Symptom Potential Cause Corrective Action
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
Electrode Coating Use bulletnose electrodes;
Downsize sensor to increase flow rate above 3 ft/s;
Periodically clean sensor
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 A, B, C, and D
(see Table 6-5 on page 6-8)
Improper wiring If electrode shield and signal wires are switched, flow indication
will be about half of what is expected. Check wiring diagrams for
your application.
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 C and D
(see Table 6-5 on page 6-8)
Sensor failure–Shorted or open coil Perform the sensor Tests A and B
(see Table 6-5 on page 6-8)
Transmitter failure Verify transmitter operation with an 8714 Calibration Standard or
replace the electronic board
Noisy Process Chemical additives upstream of
magnetic flowmeter
Complete the Noisy Process Basic procedure. Move injection
point downstream of magnetic flowmeter, or move magnetic
flowmeter.
Sludge flows–Mining/Coal/
Sand/Slurries (other slurries with
hard particles)
Decrease flow rate below 10 ft/s
Styrofoam or other insulating particles
in process
Complete the Noisy Process Basic procedure;
Consult factory
Electrode coating Use replaceable electrodes in Rosemount 8705.
Use a smaller sensor to increase flow rate above 3 ft/s.
Periodically clean sensor.
Air in line Move the sensor to another location in the process line to
ensure that it is full under all conditions.
Low conductivity fluids (below 10
microsiemens/cm)
• Trim electrode and coil wires – see “Conduit Cables” on
page 2-6
• Keep flow rate below 3 FPS
• Integral mount transmitter
• Use 8712-0752-1,3 cable
• Use N0 approval sensor
Advanced Troubleshooting continued on next page