Xylem 201690, Руководство по эксплуатации

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Maintenance, cleaning, disposal, and replacement TriOxmatic
®
690
20 ba25314e05 09/2020
Precision
measurements
Recommendation: In order to carry out precision measurements, leave
the sensor to polarize for a longer period of time, e.g. overnight, and
recalibrate it the following day.
5.4 Cleaning the electrodes
The counter electrode and reference electrode always show a
coloration. This is necessary for the operation of the sensor.
This is not contamination. Cleaning is only required in cases of slopes
that are too small or too large (the sensor cannot then be calibrated)
that cannot be resolved by changing the membrane cap and electrolyte
solution.
NOTE
Before unscrewing the membrane cap, disconnect the sensor from the
instrument. Otherwise, undesirable electrochemical reactions can oc-
cur that may lead to the destruction of the sensor.
Preparatory activities
In the following cases, you must refill the sensor once
more:

If there are large air bubbles

If there are air bubbles on the gold working electrode

For measurements at high water pressure, even if small
air bubbles are present. Otherwise, the membrane and,
as a result, the measuring characteristics could change.

If the sensor cannot be calibrated.
1 Pull the sensor out of the sample.
2 Get rid of any coarse contamination on the sensor (e.g. brush
it off in a bucket of tap water, wash it down with a hose or wash
it off with a cloth).
3 Disconnect the sensor from the instrument.