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CLEANING PROCEDURE
General
Soak in Hanna
HI 7061
General Cleaning Solu-
tion for approximately ½ hour.
Removal of films, dirt or deposits on the membrane/junction:
Protein
Soak in Hanna
HI 7073
Protein Cleaning Solu-
tion for 15 minutes.
Inorganic
Soak in Hanna
HI 7074
Inorganic Cleaning
Solution for 15 minutes.
Oil/grease
Rinse with Hanna
HI 7077
Oil and Fat Clean-
ing Solution.
IMPORTANT:
After performing any of the cleaning procedures rinse
the electrode thoroughly with tap water and soak the electrode in
HI 70300
Storage Solution for at least 1 hour before taking a
measurement.
TROUBLESHOOTING
Evaluate your electrode performance on pH measurements based on
the following.
•
Noise
(Readings fluctuate up and down) could be due to:
- Clogged/Dirty Junction:
Refer to the Cleaning Procedure
above.
•
Dry Membrane/Junction:
Soak in Storage Solution
HI 70300
for at least 1 hour.
•
Drifting:
Soak the electrode tip in warm Hanna Solution
HI 7082
for one hour and rinse tip with distilled water (refill with fresh
HI 7071
for single junction electrodes and
HI 7082
for double
junction electrodes if necessary).
•
Low Slope:
Refer to the cleaning procedure above.
•
No Slope:
- Check the electrode for cracks in glass stem or
bulb (replace the electrode if cracks are found).
- Make sure cable and connections are not dam-
aged nor lying in a pool of water or solution.
•
Slow Response/Excessive Drift:
Soak the tip in Hanna Solu-
tion
HI 7061
for 30 minutes, rinse thoroughly in distilled water
and then follow the Cleaning Procedure above.
Note:
for field applications, it is always recommended to keep a spare
electrode handy. When anomalies are not resolved with simple
maintenance, change the electrode (and recalibrate the meter)
to see if the problem is alleviated.
ELECTRODE CONDITIONING
ELECTRODE CONDITIONING
ELECTRODE CONDITIONING
ELECTRODE CONDITIONING
ELECTRODE CONDITIONING
AND MAINTENANCE
AND MAINTENANCE
AND MAINTENANCE
AND MAINTENANCE
AND MAINTENANCE
PREPARATION
Remove the protective cap.
DO NOT BE ALARMED IF ANY SALT DEPOSITS ARE PRESENT.
This is normal with pH electrodes and they will disappear when rinsed
with water.
During transport tiny bubbles of air may have formed inside the glass
bulb. The pH electrode cannot function properly under these condi-
tions. These bubbles can be removed by "shaking down" the electrode
as you would do with a glass thermometer.
If the bulb and/or junction are dry, soak the electrode in
HI 70300
Storage Solution
for at least one hour.
TEST MEASUREMENT
Rinse the electrode tip with tap water.
Immerse the tip (bottom 4 cm / 1½") in the sample and stir gently for
approx. 30 seconds. Light tapping of the electrode on the bottom of
the beaker is sometimes necessary to eliminate air bubble trapped in
the electrode tip that could affect the EC/TDS reading.
For a faster response of the pH reading and to avoid cross contamina-
tion of the samples, rinse the electrode tip with the solution to be
tested, before taking your measurements.
STORAGE
When not in use, replace the protective cap.
PERIODIC MAINTENANCE
Inspect the electrode and the cable. The cable used for the connection to
the meter 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.
HI 1285
is a combined pH/EC/TDS electrode with built-in temperature sensor for EC/TDS
automatic temperature compensation. The probe screened cable is 1 m (3.3") long.
