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pH CALIBRATION PROCEDURE
For greatest accuracy, it is recommended that the instrument is
calibrated 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:
(4.01)
(6.86 / 7.01)
(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 meter is equipped with a
stability indicator 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 CAL when the meter displays pH
measurement.
3. Enter the password (if different from "0000") with the arrow keys.
4. Press ALT and CFM to confirm the password or CAL to exit.
5. If password is correct, the meter displays "7.01pH" on the lower
LCD with the "BUF 1" and "CAL" indication. The upper LCD shows
the uncalibrated pH reading.
TAKING ORP MEASUREMENTS
(HI98150 ONLY)
Connect the ORP electrode to the meter and press the ON/OFF key.
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.
Note:
The ORP electrodes are not provided with the temperature
sensor.
By continuously pressing the RANGE key the following information will
be displayed on the upper LCD:
• Time
• Day - Month
• Year
Pressing RANGE again, the meter returns to mV reading.
Note:
If measurements are taken successively in different samples, it
is recommended to rinse the electrode thoroughly with deion-
ized 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 to be tested.
The temperature sensor is integrated in the pH electrode.
Immerse the pH electrode in the solution (allow a few minutes for the
temperature to stabilize) and press the ON/OFF key. The temperature
is displayed in the lower LCD.
Note:
If temperature measurement is out of range the LCD will
display " - - -".
TAKING TEMPERATURE MEASUREMENTS
