Hanna Instruments HI 98140 - Manual (Page 6)

11 10
Connect the pH electrode with the built-in tempera-
ture sensor to the meter and press ON/OFF to
power on the instrument. The meter automatically
checks that the stored calibration data correspond to the connected
electrode. The pH range will be automatically set.
If the pH electrode is not connected the LCD will display the "no
probe" message and then dashed lines in place of the readings.
For greatest accuracy, it is recommended to set
the Calibration alarm time-out to the value
appropriate to your specific use and calibrate
the meter as soon as the "DATE" warning
symbol blinks on LCD (see GLP section).
To take pH measurements, simply submerge
the bottom 4 cm (1½") of the electrode in
the solution to be tested and stir gently.
Allow for the reading to stabilize.
The temperature is displayed in the lower LCD.
The pH reading is automatically temperature compensated (ATC).
If the meter displays "----" it means that the reading is out of range.
A blinking reading means that the electrode is "dead".
By continuously pressing the RANGE key the
following information will be displayed on
the upper LCD:
• mV reading (HI98150 only)
The mV scale is autoranging, when the
reading is outside ±600mV the decimal
point automatically disappears.
• Time
• Day - Month
• Year
Pressing RANGE again, the meter returns to pH reading.
Note: When date or time is displayed, it is possible to change them
pressing ALT and FNC with no need to enter setup mode.
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.
TAKING pH MEASUREMENTS
1 The meter automatically checks for entered time/date accuracy as follows:
0 ≤ hh ≤ 23; 0 ≤ mm ≤ 59; 01 ≤ dd ≤ 28/29/30/31; 1 ≤ MM ≤ 12; 1998 ≤ YYYY ≤ 2097.
2 To change the password, the correct code must be entered first. If the password
has been forgotten, the password protected features are no longer accessible;
in this case contact your nearest Hanna Service Center.
Some of the setup parameters are explained below.
Code 00 - Setting the identification (ID) code
When using several identical meters it may be useful to uniquely
identify them by assigning an ID code to each meter.
• Select code 00.
• Enter a 4-digit value using the arrow keys.
• Press ALT and CFM to confirm the value.
Code 20 - Auto-off
The auto-off timeout is fixed at 5 minutes.
• Select code 20 to enable/disable this feature.
Code 22 - Battery level test
• Select code 22.
• If the meter is connected to an external power adapter, the LCD
will display "LINE" otherwise it will display "bAtt" on the upper
display, and the remaining percentage
of battery charge (100% means fully
charged battery and 0% corresponds to
the minimum battery voltage that allows
the meter to operate).
Note: the battery level test is also performed any time the meter is
turned on.