YSI IQ S ENSOR N ET TriOxmatic 702 IQ - Manual (Page 29)

TriOxmatic
®
702 IQ Maintenance, cleaning, disposal, and replacement
5 - 7 ba76048e01 01/2012
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.
Note
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.
5.4 Cleaning the electrodes
The counter electrode and reference electrode always exhibit a distinct
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 head and the electrolyte solution.
Caution
To clean the electrodes, always unscrew the sensor from the
SACIQ sensor connection cable. Otherwise, undesirable
electrochemical reactions can occur that may lead to the
destruction of the sensor.
Preparatory activities
10 The filling should be free of air bubbles as far as possible.
However, small air bubbles do not cause any interference.
11 After approx. 60 minutes polarization time, the sensor is ready
for operation.
12 Recalibrate the sensor (see section 4.2 C ALIBRATION ).
1 Take the sensor out of the flow-thru vessel.
2 Unscrew the sensor from the SACIQ sensor connection cable
(see section 5.1 G
ENERAL MAINTENANCE INSTRUCTIONS ).