Xylem WTW SenTix 950, Руководство по эксплуатации

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SenTix
®
950 / 980 / Micro 900(-P) Storage
7
ba75843e04 06/2017
Subsequent
calibrations
The frequency of subsequent calibrations depends on the application. The
meters provide an option where you can enter a calibration interval. After the
calibration interval has expired, the meter will automatically remind you of the
due calibration.
3 Storage
During short
measuring breaks
With the refilling opening open, immerse the electrode in reference electro-
lyte (KCl 3 mol/l, Ag
+
free). Prior to the next measurement, shortly rinse the
electrode with the test sample or deionized water.
Overnight or
longer
Put the clean electrode in the watering cap that is filled with reference elec-
trolyte (KCl 3 mol/l, Ag
+
free) and close the refilling opening.
NOTE
pH electrodes must not be stored dry or in deionized water. The elec-
trode could be permanently damaged by this. If the liquid in the
watering cap has dried up, condition the electrode in reference electro-
lyte (KCl 3 mol/l, Ag+ free) for at least 24 hours.
4 Aging
pH electrodes are consumables. Every pH electrode undergoes a natural
aging process. With aging, the responding behavior becomes slower and the
electrode slope and asymmetry change. Moreover, extreme operating condi-
tions can considerably shorten the lifetime of the electrode. These are:
 Strong acids or lyes, hydrofluoric acid, organic solvents, oils, fats, bro-
mides, sulfides, iodides, proteins
 High temperatures

High changes in pH and temperature.
The warranty does not cover failure caused by measuring conditions and
mechanical damage.
Prevent contact of the pH membrane to the beaker bottom to
avoid scratches on the pH membrane.
During longer storing periods, salt sediments may develop on the
watering cap. They do not affect the measuring characteristics
and can easily be removed with deionized water when the elec-
trode is put into operation again.