4-Electrode Conductivity Diagnostics - ABB AWT420 Operating Instruction

86 AW T4 2 0 | U N I V E R S A L 4 - W I R E , D U A L- I N P U T T R A N S M I T T E R | O I/A W T4 2 0 - E N R E V. B
...16 Troubleshooting
...Diagnostic messages

4-electrode conductivity diagnostics

NAMUR Diagnostic
icon message
S(n):
ADC Failure
S(n):
Memory Failure
S(n):
PT Failure
S(n):
PV Failure
S(n):
Calibrating
S(n):
Recovery
S(n):
Cal Failed
S(n):
PV Out of Limits
S(n):Process
Temp Out of
Range
S(n):Internal
Temp Out of
Range
S(n):
Polarization
Cause
Failure of the analog to digital converter in the
sensor/sensor module.
Sensor configuration data is corrupt, or the
sensor's non-volatile memory is faulty.
The sensor configuration may be affected and
changes may not be maintained after power
cycle.
The measurement taken from the temperature
sensor is invalid indicating that the temperature
sensor has failed, or the associated connections
are either open-circuit or short-circuit.
A primary variable reading cannot be obtained
from the conductivity sensor.
Sensor calibration is in progress.
Recovery diagnostic is active during the period
between completion of a sensor calibration and
the sensor being ready to make accurate
measurements.
The most recent sensor calibration has failed,
calibration coefficients have not been updated
and the previous values continue to be applied.
Process value (PV) measured is outside the
specified limits of the sensor.
Refer to the sensor data sheet to determine
the operating range.
Solution temperature is outside the
measurement range of the sensor.
Refer to the sensor data sheet to determine
the temperature range.
The sensor module measurement circuitry is
operating at a temperature outside its
recommended range.
This may cause the measurements to be
inaccurate.
Sensor readings indicate that the 4-electrode
conductivity sensor is dirty, i.e. foreign material
has collected in the sensor.
This causes measurement inaccuracy and
eventual degradation of the sensor.
Recovery action
Cycle power to the transmitter.
If Sensor ADC Failure persists, contact local service organization.
Cycle power to the transmitter.
If Sensor Memory Failure persists, check all configuration parameters for
all sensors and correct any errors. Save the configuration to SD card or
via Bluetooth App.
Reset the sensor to defaults from the Sensor Setup menu and reload the
saved configuration.
If Sensor Memory Failure persists, contact local service organization.
Visually inspect the sensor/temperature sensor for signs of damage.
A damaged sensor must be replaced.
Check wiring to sensor module terminals 5 to 8.
If Process Temperature Failure persists, contact local service
organization.
Check the wiring of the sensor to the sensor module (terminals 1 to 4).
Visually inspect the sensor for signs of damage.
Cycle power to the transmitter.
If PV Failure persists, contact local service organization.
Diagnostic clears once calibration is complete.
Diagnostic clears once recovery is complete.
Visually inspect sensor for signs of damage or dirt and clean if necessary.
Check that sensor is fully submerged in the solution.
Repeat calibration, if Calibration Failed persists, consider replacing the
sensor.
Check the process and the position of the sensor.
If PV Out of Limits is consistently active it may be necessary to replace
the sensor with an alternative with a wider, or more appropriate
operating range. Contact local service organization for potential
solutions
Ensure that the solution temperature is within the sensor measurement
limits.
Check the process and reduce the effect of any potential heat sources.
If Process Temperature Out of Range is consistently active it may be
necessary to replace the sensor with an alternative with a wider, or more
appropriate temperature range. Contact local service organization for
potential solutions.
Ensure that the ambient temperature of the transmitter containing the
sensor module is within its operating range. –10 to 75 °C [14 to 167 °F]
If Internal Temperature Out of Range persists, contact local service
organization.
Remove the sensor from the process and visually inspect, remove any
foreign material and clean with a neutral solution.
If Dirty Sensor diagnostic persists, contact local service organization.