25
Take a new membrane assembly from SPK and, holding the assembly verti-
cally, fill electrolyte with it. Then carefully fit the assembly with electrolyte over the
bushing and place the protective bushing.
After membrane assembly/teflon film replacement, perform the steps de-
tailed in para.2.3.3 and 2.3.4.
2.6.5 Platinum electrode cleaning
A need for platinum electrode cleaning in a special solution arises in
6-12 months after the first use. It is not recommended to clean the electrode before
this period expires.
To clean the electrode, prepare two solutions.
Solution composition:
Solution1: chlorohydric acid (concentrated) − 50 cm
3
,
distilled water
up to 100 cm
3
;
Solution 2: acetic acid (80 to 100 %).
Pour the solutions into vessels making sure that the liquid level is up to
3 mm. Then proceed as follows:
remove the teflon film;
wash the sensor with distilled water;
place the sensor into a vessel with Solution 1 and hold it there for 1 h;
wash the sensor with distilled water;
place the sensor into a vessel with Solution 2 and hold it there also for
1 h;
WARNING: NEVER PLACE the silver anode in the above solutions!
wash the sensor with distilled water.
Then proceed to para.2.6.4.2.
2.6.6 Analyzer initial parameter setting
The instrument features a mode for setting the analyzer initial parameters of
shift (zero shift) and slope corresponding to the averaged sensor. This mode ena-
bles calibration to be always performed from the fixed initial conditions.
Use this mode when in doubt as to whether the analyzer has operated cor-
rectly in performing calibration modes.
