A DS 4 20
| D I SS O LV ED OX YG EN SEN S O R | O I/A DS 4 2 0 - EN R E V. B
15
6 Diagnostics
The table below shows sensor-specific icon types, diagnostic
messages and possible causes/suggested remedial action.
Note .
• The diagnostic icons in the following tables conform to
NAMUR 107.
• For transmitter-specific diagnostics messages, refer to
NAMUR 107 diagnostic icons
Failure
Check
function
Out of
specification
Maintenance
required
Process value
invalid due to
malfunction in
sensor or
transmitter
Process value
temporarily invalid
due to specified
action
Process value
unreliable due to
sensor operating
outside specified
range/limits
Process value valid
– intervention
required to correct
operational
conditions
S(n): PT failure
Diagnostic message
S(n): PT failure
Cause
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.
Recovery action
1
Visually inspect the sensor/temperature sensor for signs of
damage. A damaged sensor must be replaced.
2
Cycle the power to the transmitter.
3
If the failure persists, contact the local service organization.
S(n): D.O. Conc Meas Error
Diagnostic message
S(n): D.O. Conc Meas Error
Cause
The DO sensor cannot provide a valid dissolved oxygen
measurement due to a sensor error.
Recovery action
1
Cycle the power to the sensor.
2
If the failure persists, contact the local service organization.
S(n): %Sat Meas Error
Diagnostic message
S(n): %Sat Meas Error
Cause
The DO sensor cannot provide a valid % saturation
measurement due to a sensor error.
Recovery action
1
Cycle the power to the sensor.
2
If the failure persists, contact the local service organization.
S(n): Calibrating
Diagnostic message
S(n): Calibrating
Cause
Sensor calibration in progress.
Recovery action
This diagnostic clears when the calibration is complete.
S(n): Internal Comms Error
Diagnostic message
S(n): Internal Comms Error
Cause
The DO sensor cannot provide a valid dissolved oxygen
measurement due to an error in the communication between
the sensor and the SmartCap.
Recovery action
1
Make sure that the SmartCap is installed and correctly
seated.
S(n): Cap Removed
Diagnostic message
S(n): Cap Removed
Cause
The SmartCap has been removed from the sensor or is not
being recognized. A valid measurement cannot be made.
Recovery action
1
Make sure that the SmartCap is installed correctly.
