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pH CALIBRATION PROCEDURE
For better accuracy, it is recommended to calibrate the instrument
frequently. For a faster procedure, it is possible to calibrate at 1
point, but it is always a good practice to calibrate at 2 points.
A two-point calibration can use any combination of the three sets:
(pH 4.01)
(pH 6.86/7.01)
(pH 9.18/10.01)
Only one value from each set can be selected. For example if pH
7.01 is used as first point, it will not be possible to select pH 6.86
as the second point.
In the case of a two-point calibration, in the acidic range (from 0 to
7 pH) use pH buffer 7.01 (or 6.86) as the first solution and pH buffer
4.01 as the second solution. If testing in the alkaline range (from 7
to 14 pH), use pH buffer 10.01 (or 9.18) as the second solution.
Due to electrode conditioning time, the electrode must be kept
immersed a few seconds to stabilize. The meters are equipped with a
stability indicator (a blinking "S") and the user will be guided step by
step with easy indications on the LCD during the calibration. This will
make the calibration a simple and error-free procedure.
pH CALIBRATION
1. Rinse the electrode with a portion of the first
calibration buffer or clean water. Dip the
bottom, 4 cm (1½"), of the electrode into a
beaker containing the solution.
2. Press ALT and CAL while meter is not printing nor logging.
3. User is prompted to enter password if it has been set to a value
different from 0000, otherwise skip to step 6.
4. Enter the password with the arrow keys.
5. Press ALT and CFM to confirm the password or ALT and CAL to
exit.
TAKING ORP MEASUREMENTS
( HI 98 24 0 ON LY )
Connect the ORP electrode to the meter and
press ON/OFF to power on the instrument.
The meter automatically sets the mV range.
If the ORP electrode is not connected, the LCD will display the "no
probe" message and then dashed lines in place of the readings.
To take ORP measurements, simply submerge the bottom 4 cm (1½")
of the ORP electrode in the solution to be tested, stir gently and allow
for the reading to stabilize.
The lower LCD displays the temperature reading, or a dashed line if
the ORP electrode is not provided with the temperature sensor.
By continuously pressing the RANGE key the following information will
be displayed on the upper LCD:
• Temperature reading
If the ORP electrode is not provided with the temperature sensor,
a dashed line will be displayed.
• Date
• Time
Pressing RANGE again, the meter returns to mV reading.
If measurements are taken successively in different samples, it is
recommended to rinse the electrode thoroughly with deionized water
or, if not available, tap water first and then with some of the next
sample to condition the electrode before immersing it in the sample.
The temperature sensor is integrated in the pH electrode.
Secure the connection of the electrode to the top of the meter and
immerse it in the sample solution (allow a few minutes for the
temperature to stabilize). Press ON/OFF to power on the instrument.
The temperature is displayed in the lower LCD without the decimal
digit during pH and mV measurement. To display the temperature
reading with decimal digit, press the "RANGE" key to get into the °C
or °F mode. The temperature value and the "°C" or "°F" symbol will
be displayed on the upper display.
Note:
To choose between "°C " and "°F" unit, enter the setup code 70.
Note:
If temperature measurement is out of range the LCD will
display "- - - -".
TAKING TEMPERATURE MEASUREMENTS