Oakton pH 5+, Operating Instructions Manual

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6. Electrode care and maintenance
Storage
For best results, keep the pH bulb wet. Store the pH bulb in the electrode soaker
bottle filled with electrode storage solution. Or you can store the electrode in a
pH 4 buffer with 1/100 part saturated KCl. Other pH buffers are also suitable for
storage. NEVER use deionized water for storage.
After measuring
1.
Rinse the electrode and reference junction in deionized water.
2.
Store the electrode as recommended in "Storage" or as recommended
by the manufacturer.
Electrode cleaning
Because your pH electrode is susceptible to dirt and contamination, clean it every
one to three months depending on extent and condition of use.
Clean the electrode in a mild detergent solution. Wipe the probe with a soft tissue
paper. Avoid touching the glass membrane with your fingers. Wash thoroughly
in tap water and then in distilled water. Recalibrate your meter after cleaning
the electrode.
Special Cleaning Tips
Salt deposit: dissolve the deposit by immersing the electrode in tap water for ten to
fifteen minutes. Then thoroughly rinse with distilled water.
Oil/grease film: wash electrode pH bulb gently in detergent solution. Rinse elec-
trode tip with distilled water.
Clogged reference junction: heat a diluted KCl solution for 60-80°C. Place the sens-
ing part of the electrode into the heated solution for about 10 minutes. Allow the
electrode to cool in some unheated KCl solution.
Protein deposits: prepare a 1% pepsin solution in 0.1M of HCl. Set the electrode in
the solution for five to ten minutes. Rinse the electrode with distilled water.
7. Troubleshooting
Problem Cause Solution
Err flashes Wrong or contaminated Use fresh buffer
on LCD buffer used during solution: pH 4.01, 7.00,
calibration or 10.00
Bad electrode Change electrode
“Ur” or “Or” on LCD pH out of range —
with pH or °C
Temperature out of range Cool/Heat sample as needed
annuciator
Bad electrode Change electrode
Bad temperature Change temperature
sensor sensor
LO annuciator Low battery Replace batteries
on LCD with fresh set
Power on but Batteries not Insert batteries
no display in place
Batteries not in Re-insert batteries
correct polarity (+ and -) with correct polarity
Weak batteries Replace batteries
Unstable Electrode not deep Place electrode
reading enough in sample deeper in sample
Insufficient Fill electrode with
reference electrolyte reference electrolyte
in electrode (if electrode is refillable);
replace electrode.
Broken electrode Replace electrode
External “noises” or Remove or switch off
induction caused by interfering motor
by nearby electric motor
Dirty electrode Clean electrode
Slow response Dirty electrode Clean electrode
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6.2
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