12
One-point calibration
••
••
• Immerse the pH electrode and the tem-
perature probe approximately 4 cm (1½")
into a buffer solution of your choice (pH
4.01, 6.86, 7.01, 9.18 or 10.01) and
stir gently. The temperature probe should
be close to the pH electrode.
• Press CAL. The "CAL" and " " indicators and the most common
"7.01" buffer will be displayed on the secondary LCD.
• If necessary, press "VC" or "WC" to
select a different buffer value.
• The "NOT READY" indication will blink on LCD until
the reading has stabilized.
• When the reading is stable, "READY" and "CFM" will blink. Press CFM
to confirm the calibration.
• If the reading is close to the selected buffer, the meter stores the
reading. The calibrated value is then displayed on the primary LCD
and the secondary LCD will display the second expected buffer value.
• If the value measured by the meter is not
close to the selected buffer, "WRONG " and
"WRONG " will blink alternately. In this case
check if the correct buffer has been used or
refresh the electrode by following the maintenance procedure below.
If necessary change the buffer or the electrode.
• Press CAL to quit calibration. The meter will return to
normal operation and memorize the one-point calibra-
tion data.
4 cm
(1½")
21
CLEANING PROCEDURE
General Soak in Hanna HI 7061 or HI 8061 General Cleaning
Solution for approximately ½ hour.
Removal of films, dirt or deposits on the membrane/junction:
-
Protein
Soak in Hanna HI 7073 or HI 8073 Protein Cleaning
Solution for 15 minutes.
-
Inorganic
Soak in Hanna HI 7074 or HI 8074 Inorganic Clean-
ing Solution for 15 minutes.
-
Oil/grease
Rinse with Hanna HI 7077 or HI 8077 Oil and Fat
Cleaning Solution.
IMPORTANT: After performing any of the cleaning procedures rinse
the electrode thoroughly with distilled water, refill the reference
chamber with fresh electrolyte (not necessary for gel-filled electrodes)
and soak the electrode in HI 70300 or HI 80300 Storage Solution
for at least 1 hour before taking measurements.
TROUBLESHOOTING
Evaluate your electrode performance based on the following.
• Noise (Readings fluctuate up and down) could be due to:
– Clogged/Dirty Junction: Refer to the Cleaning Procedure above.
– Loss of shielding due to low electrolyte level (in refillable
electrodes only): refill with fresh HI 7071 or HI 8071 for
single junction or HI 7082 or HI 8082 for double junction
electrodes.
• Dry Membrane/Junction: Soak in HI 70300 or HI 80300 Stor-
age Solution for at least 1 hour.
• Drifting: Soak the electrode tip in warm (approx. 50-60C) Hanna
HI 7082 or HI 8082 Solutions for one hour and rinse the tip
with distilled water. Refill with fresh HI 7071 or HI 8071 for
single junction electrodes and HI 7082 or HI 8082 for double
junction electrodes (refillable electrodes only).
• Low Slope: Refer to the cleaning procedure above.
• No Slope: Check the electrode for cracks in glass stem or bulb
and replace the electrode.
• Slow Response/Excessive Drift: Soak the tip in HI 7061 or
HI 8061 Solutions for 30 minutes, rinse thoroughly in distilled
water and then follow the Cleaning Procedure above.
To Next Page
Loading...
Need help?
General
