Hanna Instruments HI 9026, Instruction Manual

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• Press the CFM key to confirm the calibra-
tion: the meter stores the first calibration
point; the primary LCD will show the
calibrated reading, while the secondary
LCD will show the second buffer to be
used for calibration (pH 4.01).
If you’re going to calibrate with a
different buffer, select the desired value
by pressing the arrow keys.
• Submerge the electrode approximately 4 cm (1½") into the
second buffer solution, place the temperature probe as close as
possible to the electrode and stir gently.
• The LCD will flash "NOT READY" for 12 seconds, then:
if the reading is not close to the selected buffer, "WRONG "
and "WRONG " will blink alternatively;
if it is close to the selected buffer the meter
will advise the user with an acoustic
signal (if enabled) when the reading
becomes stable and the display will change
to "READY" and blinking "CFM".
• Press the CFM key: the value is stored in memory and the meter
returns to normal mode. The tags corresponding to the buffers
used for calibration will light up together with the “condition”
bargraph (if enabled).
Note: The meter automatically skips the buffer used for the first calibration
point to avoid erroneous procedure. A difference of at least 1.5 pH
unit is required between the two buffers used for the offset and slope
calibration: once calibrated at either pH 7.01 or 6.86, the
instrument automatically ignores the other value for the second point
(same for pH 10.01 and 9.18).
Note: During calibration, the secondary LCD shows the selected buffer
value; press RANGE to display the buffer temperature.
Note: To clear a previous calibration and return to the default
values, press CLR at any time after entering the calibration
mode. The LCD will show “CLr CAL” for one second, and then
will return to normal measurement mode.
The LCD will show an empty bargraph to warn the user that
the meter is not calibrated.
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For refillable electrodes, if the refill solution (electrolyte) is more than 2½
cm (1") below the fill hole, add the appropriate Electrolyte Solution.
MEASUREMENT
Rinse the electrode tip with distilled water, immerse it (4 cm / 1½")
in the sample and stir gently for a few 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
any measurements.
STORAGE PROCEDURE
To minimize clogging and ensure a quick response time, the glass
bulb and the junction should always be kept moist.
When not in use, store it with a few drops of HI 70300 storage
solution in the protective cap.
NEVER STORE THE ELECTRODE IN DISTILLED OR DEIONIZED
WATER.
PERIODIC MAINTENANCE
Inspect electrode and 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. If any
scratches or cracks are present, replace the electrode. Rinse off any salt
deposits with water.
Connectors must be perfectly clean and dry.
For refillable electrodes:
Refill the electrode with fresh electrolyte (see the electrode’s specifications
to select the correct refilling solution). Allow the electrode to stand
upright for 1 hour. Follow the Storage Procedure above.
CLEANING PROCEDURE
• General Soak in Hanna HI 7061 General Cleaning
Solution for approximately ½ hour.
• Protein Soak in Hanna HI 7073 Protein Cleaning
Solution for 15 min.
• Inorganic Soak in Hanna HI 7074 Inorganic
CleaningSolution for 15 min.
• Oil/grease Rinse with Hanna HI 7077 Oil & Fat Cleaning
Solution for 1 min.
IMPORTANT: After performing any of the cleaning procedures, rinse
the electrode thoroughly with distilled water and soak it in HI 70300
Storage Solution for at least 1 hour before taking measurements.