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are completely immersed into the water and free of air bubbles.
Perform the calibration as described in chapter 5.2.3.
Do not store the sensors in this solution and rinse them carefully
after calibration with demineralized water. Especially the
retractable needle-type sensors (item no.
OXR50
,
OXR230
,
OXR430
) need to be rinsed very thoroughly, because salt
crystallization within the needle might damage them irreversibly.
12.2.2
Nitrogen Gas
Flush 100% nitrogen gas through a glass flask (e.g. Duran flask)
with a lid prepared with holes for inserting the oxygen sensor and a
temperature sensor. Ensure that all air has been replaced by the
nitrogen gas before performing the calibration. Insert the oxygen
sensor and the temperature sensor into the flask, let it equilibrate
and perform the calibration as described in chapter 5.2.3.
Ensure that no ambient air enters the flask again during the
calibration process. Convectional gas transport is a very fast
process! It is therefore advised to keep flushing the flask with
nitrogen gas during the complete calibration process!
Please consider that nitrogen gas from gas bottles might be
significantly cooled down by the decompression process. Ensure a
correct temperature determination of the calibration standard!
