- 11 -
Table - 4 Self-diagnosis information in pH measurement mode
Display
Icon
Contents
Checking
Press before measuring
value becomes stable.
Press when icon appears and stays.
Wrong pH buffer solution or the
buffer solution out of range.
1.
Check whether pH buffer solution is correct.
2.
Check whether the meter connects the
electrode properly.
3.
Check whether the electrode is damaged.
During calibration, the measuring
value being unstable (
≥
3min).
1.
Check whether there are air bubbles in glass
bulb.
2.
Replace with a new pH electrode.
pH electrode zero electric potential
out of range (<-60mV or >60mV)
Electrode slope<75%
1.
Check whether there are air bubbles in glass
bulb.
2.
Check whether pH buffer solution is correct.
3.
Replace with a new pH electrode.
4.9
Maintenance of the pH Electrode
4.9.1
Daily maintenance
The soaking solution contained in the supplied protective bottle is used to maintain hydration of the
glass bulb and liquid junction. Loose the cap, take out the electrode and rinse in distilled or deionized
water before taking a measurement. Insert the electrode and tighten the cap after measurements
to prevent the solution from leaking. If the storage solution is cloudy or moldy, rinse the bottle and
replace the soaking solution (The method to prepare dissolve 26 gm KCl into 100ml distilled water).
Make sure the meter is dry and clean all the time, especially the sockets and connectors, or else it
may lead to measurement inaccuracy or invalid readings.
Once contaminated, use cotton and water free alcohol to wipe clean and allow it to dry.
*The electrode should
NOT
be soaked and stored in
purified or distilled
water, protein solution, acid
fluoride solution or organic lipids. Storing in distilled or deionized water will cause the electrolyte to
be diluted and will result in unstable readings.