17
16
pH MEASUREMENTS
Connect the pH electrode with the built-in
temperature sensor to the meter and press
ON/OFF to power on the instrument.
If the electrode is not connected the LCD will display the "no probe"
message and then dashes.
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, remove the elec-
trode protective cap and simply submerge
the tip (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 on the secondary LCD.
The pH reading is automatically temperature compensated (ATC).
If the reading is out of range, the meter displays "----". A blinking
reading means that the electrode is "dead".
By continuously pressing the DISPLAY key
the following information will be displayed
on the primary LCD:
• mV reading (the mV scale is auto-ranging:
when the reading is outside ±600 mV,
the decimal point automatically disappears).
• Time
• Day / Month
• Year
Pressing DISPLAY again, the meter returns to pH reading.
Note:
When date or time is displayed, it is possible to change them
directly by pressing (ALT+) SETUP.
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 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 CFM to confirm the value.
Code 20 - Auto-off
The auto-off time-out is factory set at 5 minutes.
• Select code 20 to disable/enable this feature.
Code 22 - Battery level test
• Select code 22.
• If the meter is connected to an external power adapter, the LCD
displays "LINE" otherwise it shows "bAtt" on the primary display, and
the remaining battery charge percentage on
the secondary one (100 means fully charged
battery and 0 indicates the minimum volt-
age that allows the meter to operate).
Note:
The battery level test is also performed any time the meter is
turned on.
Code 90 - HI 504910 terminal
• Select code 90.
• Press CFM to confirm the value.
•
HI 504920
enters a "terminal mode" during which it works as
keyboard and LCD for
HI 504910
, allowing complete calibration,
configuration and error check of
HI 504910
(see the
HI 504910
instruction manual for details).
Note:
The "LOG" tag blinks while in
HI 504910
terminal mode.
• Press (ALT+) TXCAL to exit this mode and skip into measurement
mode.
Put HI 504910 in normal measurement mode before
exiting
.
Note:
The LCD shows the "rSEr" message when a connection between
HI 504920
and
HI 504910
can not be established. In this
case, check interface cable and connections.