SATO SK-640PH, Инструкция по эксплуатации, Страница: 13 / 19

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About the glass electrode
(1) Storage
If left unused for a long time, the glass electrode becomes too dry to measure the pH accurately.
The pH electrode works best and shows accurate readings when used with moderate moisture.
When using the instrument for the first time after purchasing or a long storage period, we
recommend placing the glass electrode in water (distilled, pure or tap water) or the pH standard
solution for at least 12 hours and performing calibration before measuring. For everyday storage,
fit the glass electrode protection bottle to the sensor probe. The glass electrode protection bottle is
filled with the phthalate standard solution (pH 4) at the factory.
(2)
Inspection and calibration
For an accurate pH measurement, perform calibration using the pH standard solution.
If there is a deviation from the expected value, adjust it before performing a pH measurement.
Note that there are cases where the pH value of the standard solution has changed from its
original value. This can happen if the pH standard solution is dirty or if storing the solution for a
long time. It is advisable to use a new pH standard solution, where applicable.
(3)
Washing
Be sure to wash the pH electrode after each pH calibration or measurement with water (distilled,
pure or tap water). If left unwashed, the liquid measured tends to form a film on the surface of the
electrode, causing measurement errors. Always wash the pH electrode every time after use.
Washing can be done with water (distilled, pure or tap water) in most cases, but if there is a
stubborn stain, use neutral detergent diluted in water to wash only the glass electrode section
(spherical part). After using neutral detergent, thoroughly rinse the electrode with water (distilled,
pure or tap water) to remove the neutral detergent, and then immerse the electrode in the pH
standard solution (pH 4) before measurement.
Note that neutral detergent cannot be used on the liquid junction of the sensor probe. Otherwise,
the performance of the inner solution could be damaged if the neutral detergent penetrates inside
the sensor.
(4)
Useful life
It is not possible to replenish or repair the inner solution of the sensor probe.
The pH electrode is a consumable. Its useful life varies depending on the liquid to be measured,
pH value or temperature.
(5)
Deposit of white potassium chloride crystals
A deposit of white crystals is sometimes found on the tip of the electrode or protection bottle; this
does not pose a problem when using the instrument. The deposit is easily washed off with tap
water.
If it does not come off with tap water, soak the electrode in warm water to remove it.
Do not lick or swallow the potassium chloride crystals. If the eyes or skin becomes contaminated
with the crystals, immediately consult a doctor.