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AO2000-LS25
LASER ANALYZERS | OI/AO2000-LS25-EN REV. D
12
Diagnosis / Troubleshooting
Error messages
During operation essential status information about the device is displayed on the LCD mounted in the transmitter / AO2000 main
unit. The instrument messages and their possible explanations and actions to be taken are given in the table below.
If no messages are displayed on the LCD, see
Transmitter unit – Fuses and LEDs
Error messages in the LCD of the transmitter unit
Fault message
Description
Troubleshooting instructions
Low transmission
WARNING
The optical transmission has dropped below the limit for reliable measurements.
This might indicate misalignment of the optical units or contamination of the
optical windows.
Clean the optical windows and check the
alignment of the flanges.
Laser line-up error
ERROR
The laser beam does not reach the detector.
Clean the optical windows and check the
alignment of the flanges.
Check the optical path for obstacles.
PLC T-read error
ERROR
Error while reading the temperature via the 4 to 20 mA analog input.
The input current from the temperature sensor is either above 23.7 mA or below
0.3 mA.
Check the electrical connection of the external
temperature sensor.
Alternatively, use the fixed temperature setting in
the analyzer.
PLC P-read error
ERROR
Failure reading pressure through 4 to 20 mA analog input.
The input current from the pressure sensor is either above 23.7 mA or below 0.3
mA.
Check the electrical connection of the external
pressure sensor.
Alternatively, use the fixed pressure setting in the
analyzer.
T-read out of range
WARNING
Input current from temperature sensor is either above 22 mA or below 3.2 mA. The
measured gas temperature may be wrong.
Check the electrical connection of the external
temperature sensor.
Alternatively, use the fixed temperature setting in
the analyzer.
P-read out of range
WARNING
Input current from pressure sensor is either above 22 mA or below 3.2 mA.
The measured gas pressure may be wrong.
Check the electrical connection of the external
temperature sensor.
Alternatively, use the fixed temperature setting in
the analyzer.
P/T out of range
WARNING
Pressure and temperature compensation is outside acceptable range.
The accuracy of the measured gas concentration may be reduced.
If supplied values are correct, the device is
operating outside specifications.
Ex-read out of range
WARNING
Input current from external gas sensor is either above 22 mA or below 3.2 mA.
Check the electrical connection of the external
flowmeter.
Voltage supply fail
The power supply voltage input to the device (transmitter unit) is exceeding
acceptable range (for standard device; 18 to 36 V).
Check and correct input voltage.
If the error persists, contact ABB Service.
