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If the bulb and/or junction are dry, soak the electrode in
HI70300 storage solution
for at least one hour.
For refillable electrodes**:
If the refill solution (electrolyte) is more than 2½ cm (1")
below the fill hole, add
HI 7082
3.5M KCl electrolyte solu-
tion for double junction or
HI 7071
3.5M KCl+AgCl
electrolyte solution for single junction electrodes.
For AmpHel
®
electrodes:
If the electrode does not respond to pH changes, the battery
is run down and the electrode should be replaced.
TEST MEASUREMENT
Rinse the electrode tip with distilled water.
Immerse the tip (bottom 4 cm / 1½") in the sample and stir
gently for approximately 30 seconds.
For a faster response and to avoid cross contamination of
the samples, rinse the electrode tip with the solution to be
tested, before taking your measurements.
STORAGE
To minimize clogging and assure a quick response time,
the glass bulb and the junction should be kept moist and
not allowed to dry out. This can be achieved by installing
the electrode in such a way that it is constantly in a well
filled with the sample (stream or tank).
When not in use, replace the solution in the protective cap
with a few drops of
HI 70300
storage solution or, in its
absence,
HI 7007
pH 7.01 buffer solution.
Follow the Preparation Procedure above before taking mea-
surements.
Note
NEVER STORE THE ELECTRODE IN DISTILLED OR DEION-
IZED WATER.
PERIODIC MAINTENANCE
Inspect the electrode and the cable. The cable used for the
connection to the controller must be intact and there must
be no points of broken insulation on the cable or cracks on
the electrode stem or bulb.
Connectors must be perfectly clean and dry. If any scratches
or cracks are present, replace the electrode. Rinse off any salt
deposits with water.
ELECTRODE CONDITIONING AND MAINTENANCE
* Only available with refillable electrodes. For industrial applications, gel-filled electrodes are preferable
due to lesser maintenance requirements.
PREPARATION
Remove the protective cap.
DO NOT BE ALARMED IF ANY SALT DEPOSITS ARE
PRESENT.
This is normal with electrodes and they will disappear when
rinsed with water.
During transport tiny bubbles of air may have formed in-
side the glass bulb. The electrode cannot function properly
under these conditions. These bubbles can be removed by
"shaking down" the electrode as you would do with a glass
thermometer.
