Crison 52 23 Manual Del Usuario página 10

pH electrodes
Introduction
They are pH electrode with screw cap S7.
52 23 suitable for food industry.
52 24 basically used to perform titrations in
non aqueous media.
Electrode preparation
Unscrew the storage protector
Verify that there are not air bubbles inside the
membrane. They can be removed by shaking
the electrode as a clinical thermometer.
Remove the cap from the electrolyte filling
port .
Before measuring, slide the plastic ring and re-
turn it to its original position, by pressing softly,
to ensure the electrical contact, see fig A. If it is
necessary, refill with reference electrolyte.
Calibration
See pH-meter instruction manual.
Measurements. Recommendations
• During calibration and measurement the
buffers and the samples must be slightly
stirred. Identical stirring speed in both cases.
• The sample must cover the electrode's
diaphragm
• After measurement, immediately rinse the
electrode with distilled water. Dry it with
soft tissue, only by contact, without rub-
bing.
• Between measurements the electrode's
membrane should be immersed in aqueous
solution. The most appropriate place is the
storage protector with some electrolyte.
Do not leave immersed in distilled water.
Maintenance
• Periodically refi ll the electrode with elec-
trolyte. Maintain the level as high as pos-
sible
• Maintain the membrane's surface clean
. Protect it from friction or knocking.
• When an electrode gets contaminated, the
simple rinsing with distilled water is not suf-
fi cient. The most suitable cleaning solution
is one which acts in a more selective way
over the contamination (look for CRISON
regeneration solutions).
• Re-hydration. A "dry" electrode recov-
ers by immersing it in CRISON cleaning
electrode solution, code 96 00, or in di-
luted HCl solution for several hours. It is
recommended to read the information
supplied with the electrode's regenerating
solutions.
Troubleshooting
... the meter always measures the same value.
Short circuit in the electrode or connector.
Substitute the electrode.
... unstable reading.
Air bubble in the membrane.
Shake the electrode as a thermometer.
... impossible to perform calibration.
... very slow response.
Dirt on the diaphragm or the membrane.
De-hydrated membrane.
Electrode ageing or wear.
Clean, regenerate, substitute electrode.
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