Aanderaa 4330 Operating Manual page 67

If you have selected to output oxygen concentration in µM in the SR10 format you will have to multiply the obtained data by 0.488281.
If you select to output % saturation you will have to multiply with 0.146484. If logging the sensors with SEAGUARD
4835) loggers using the AiCap communication protocol will automatically give out calibrated data with full resolution when connected to the logger.
The same is true if logging the sensor with serial communication.
5. Converting the analog output signal (4831 or via Analog Adaptor 3966) will normally require use of scaling coefficients. These coefficients are
dependent on for which parameter and range the outputs are configured. When the Optode is configured to analog output mode these coefficients
will be presented at the RS232 interface at power up or reset.
CCAP2
Q: If I change the foil and forget to update the internal constants but I made a new calibration can I back-calculate to get the correct data?
A. If the foil is from the same batch it will have the same constants and the data should be ok.
If the foil is not from the same batch it will not be possible to post-compensate the obtained data.
It is imperative to use the correct foil constants and to do a new two-point calibration if the foil has been changed or moved.
CCAP3
Q: On the paper the specifications of the AADI Optodes appears to be conservative compared to specifications given for other sensors on the market, why?
A: After calibration the sensors normally perform better than the given specifications.
Aanderaa has a tradition to be conservative when giving sensor specifications so that these reflect the performance in the field not the best specifications
you can obtain in the laboratory.
CCAP4
Q: Can the accuracy of the sensor be further improved?
A: Yes, if the individual sensor was calibrated in more calibration points (e.g. 30-40 point calibration), both with respect to oxygen concentration and
temperature compensation of the foil, the accuracy would be improved by approximately a factor of 4.
Starting in the first half of 2012 AADI offers a multipoint factory calibration which give absolute accuracies of ±2 µM or ±1.5 %over the whole range of
temperatures and oxygen concentrations. Some customers have also established their own calibration procedures.
CCAP5
Q: How often do I need to re-calibrate the sensor?
A: If the foil is not mechanically damaged or moved no recalibrations are normally needed.
In our documentation we recommend a recalibration once a year but ample field experiences have demonstrated that these optodes are stable over much
longer time periods than this. The longest field deployments without sensor drift has lasted 6 years.
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page 67 of 93
TD 269 OPERATING MANUAL
OXYGEN OPTODE 4330, 4831, 4835
June 2017
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and/or Smartguard (4330 or