OHAUS ST350 Instrucciones Generales página 6

ST350 electrodes EN-3
2. How do you properly store the pH
electrode after every use?
A: Rinse the electrode with pure water, put
the electrode into the watering cap. If the
solution in the cap is polluted or dry, clean it
and fill it with 3M KCl solution.
3.What's the life of the pH electrodes?
A: Measured samples, storage conditions
and maintenance methods all could influence
the life of pH electrodes; normally a pH
electrode expires after 12 months. Some
sample, such as strong acid or alkali,
corrosive liquid will shorten the pH electrode
life. pH electrode is consumable, is generally
provided warranty.
4.why is the pH value not stable when
measuring pure water ?
A: generally, the common pH electrode
couldn't measure distilled water, rainwater or
pure water. Because they are the liquids,
which have low conductivity.