YSI TruLine 21 - Manual (Page 7)

TruLine Storage
T 814240 04/2014 7
During short
measuring breaks
Storage
Immerse the combination electrode in reference electrolyte (KCl 3 mol/L,
Ag
+
free). Prior to the next measurement, shortly rinse the combination
electrode with the test sample or deionized water.
Note
Prevent contact of the pH membrane to the beaker bottom to avoid scratches
on the pH membrane.
Overnight or
longer
Put the clean combination electrode in the watering cap that is filled with
reference electrolyte (KCl 3 mol/L, Ag
+
free).
Note
pH combination electrodes must not be stored dry or in deionized water. The
combination electrode could be permanently damaged by this. If the liquid in
the watering cap has dried up, condition the combination electrode in
reference electrolyte (KCl 3 mol/L, Ag + free) for at least 24 hours.
Note
During longer storing periods, salt sediments may develop on the watering
cap. They do not affect the measuring characteristics and can easily be re-
moved with deionized water when the combination electrode is put into oper-
ation again.
Aging
Every pH combination electrode undergoes a natural aging process. W ith ag-
ing, the responding behavior becomes slower and the electrode slope and
asymmetry change. Moreover, extreme operating conditions can consider-
ably shorten the lifetime of the combination 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.