Monitoring The Electrode Impedance; Measurements On The Flowmeter - ABB ProcessMaster FEM630 Operating Instructions Manual

FE M63 0 | E L EC TR OM AG N E T I C FLOWM E T E R | O I/F E M6 3 0-EN RE V. A
9 . . .Diagnosis / error messages
. . .Extended diagnostic functions

Monitoring the electrode impedance

The measurement monitors the impedance between the
measuring electrode and grounding and activates an alarm
if the impedance drops below a limit. The function is
activated together with the conductivity measurement.
Requirements for use:
• Conductivity of the measuring medium: 20 to 20000 μS/
cm.
Additional installation conditions:
• When using plastic piping, install a grounding plate at the
front and back of the device.
• There must not be any deposits on the measuring elec-
trodes.
• The measuring tube must always be completely full, and
the measuring medium must have only minor deviations in
conductivity.

Measurements on the flowmeter

Coil inductance, coil current, coil resistance
The diagnosis of the coil in the sensor includes coil
inductance, current and resistance.
Flowmeter sensor temperature
The coil temperature monitoring triggers an alarm via the
digital output, if configured.
The minimum and maximum alarm value for the coil
temperature can be set.
The coil temperature is a function of the ambient
temperature and measuring medium temperature.
Compliance with the temperature specification of the
sensor liner can thus be monitored.
Setup
Menu / parameter
Diagnostics / ...Diagnosis Control / ...Diagnosis Coil
Coil Diag On/Off Activate the function.
Coil Resistor Display the coil resistance.
Coil Current Display the coil current.
Coil Inductance Display the coil inductance.
Display the coil temperature within the
Coil Temperature
sensor.
Measurement of coil temperature must be
set in accordance with the conditions on-
Coil Temperature Adj
site. Temperature measured with a separate
thermometer can be entered here.
Min. and max. alarm for the sensor
Coil Temp. Min Alarm
temperature (coil temperature). Can be used
to monitor the temperature limit of the
Coil Temp. Max Alarm
meter tube liner
Transmitter monitoring
Monitoring the temperature of the electronic unit in the
transmitter triggers an alarm via the digital output, if
configured.
In the '...Diagnosis Values', the current temperature as well
as the smallest and largest previously measured
temperature is displayed.
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