User Guide
To turn the meter on
Connect the pH electrode to the meter.
Connect the 12VDC adapter to the meter and to the mains;
the display will lit. Press and hold the MODE button for 2-
3 seconds. All the used segments on the LCD will be visible
for a few seconds.
To change the temperature unit
To change the temperature unit (from °C to °F), from
measurement mode, press and hold the MODE button until
TEMP and the current temperature unit are displayed on
the lower LCD. Eg. TEMP °C.
Use the SET/HOLD button to change the temperature unit,
and then press MODE button twice to return to normal
measurement mode.
To freeze the display
Press and hold the SET/HOLD button for 2-3 seconds until
HOLD appears on the secondary display.
Press either button to return to normal mode.
Taking measurements
Immerse the electrode and the tem-
perature probe in the solution to be
tested. In order to ensure better ac-
curacy, the electrode should not touch
or stand close to the walls or bottom
of the sample vessel.
The pH value automatically compen-
sated for temperature is shown on
the primary LCD while the secondary
LCD shows the temperature of the
sample.
The measurements should be taken when the stability
symbol on the top left of the LCD disappears.
Note:
Measurements have to be taken with both probes (pH-
electrode and temperature probe) immersed in the
same vessel.
OPERATIONAL GUIDE
Calibration buffer set
• From measurement mode, press and hold the MODE
button until TEMP and the current temperature unit are
displayed on the lower LCD. Eg. TEMP °C.
• Press the MODE button again to show the current buffer
set: pH 7.01 BUFF (for 4.01/7.01/10.01 calibration) or
pH 6.86 BUFF (for NIST 4.01/6.86/9.18 calibration).
• Press the SET/HOLD button to change the buffer value.
• Press the MODE button to return to the normal mode.
Calibration procedure
From measurement mode, press and hold the MODE button
until CAL is displayed on the lower LCD. Release the
button. The LCD will display pH 7.01 USE (or pH 6.86
USE if you have selected the NIST buffer set). The CAL
tag blinks on the LCD.
• For a single-point pH calibration, place the electrode and
the temperature probe in any buffer from the selected buffer
set (eg. pH 7.01 or pH 4.01 or pH 10.01). The meter will
recognize the buffer value automatically.
If using pH 4.01 or pH 10.01, the meter will display OK
for 1 second and then return to measurement mode.
If using pH 7.01, after recognition of the buffer the meter
will ask for pH 4.01 as second calibration point. Press the
MODE button to return to measurement mode or, if desired,
proceed with the 2-point calibration as explained below.
Note: for better accuracy it is always recommended to carry
out a two-point calibration.
• For a two-point pH calibration, place the electrode and
the temperature probe in pH 7.01 (or 6.86 if you have
selected the NIST buffer set). The meter will recognize the
buffer value and then display pH 4.01 USE.
Rinse the electrode thoroughly to eliminate cross-contamina-
tion.
Place the electrode in the second buffer value (pH 4.01 or
10.01, or, if using NIST, pH 4.01 or 9.18). When the
second buffer is recognized, the LCD will display OK for 1
second and the meter will return to the normal mode.
Note: for storing calibration data in the non-volatile memory,
turn the meter OFF and then ON again through the MODE
button.
The CAL symbol on the LCD means that the meter is
calibrated.
pH ELECTRODE MAINTENANCE
• When not in use, rinse the electrode with water to
minimize contamination and store it with a few drops of
storage (HI 70300) or pH 7 (HI 7007) solution in the
protective cap after use.
DO NOT USE DISTILLED OR DEIONIZED WATER FOR STOR-
AGE PURPOSES.
• If the electrode has been left dry, soak in a storage or pH
7 solution for at least one hour to reactivate it.
• To prolong the life of the pH electrode, it is recommended
to clean it monthly by immersing it in the HI 7061 cleaning
solution for half an hour. Afterwards, rinse it thoroughly
with tap water and recalibrate the meter.
ACCESSORIES
HI 1293D Replaceable pH electrode with differential input,
pipe thread 1/2’’ NPT & DIN connector
HI 1294 (*) Temperature probe, pipe thread 1/2’’ NPT (works also
as matching pin for pH electrode)
HI 70004P pH 4.01 solution, 20 mL sachet (25 pcs)
HI 70006P pH 6.86 solution, 20 mL sachet (25 pcs)
HI 70007P pH 7.01 solution, 20 mL sachet (25 pcs)
HI 70009P pH 9.18 solution, 20 mL sachet (25 pcs)
HI 70010P pH 10.01 solution, 20 mL sachet (25 pcs)
HI 7004M pH 4.01 solution, 230 mL bottle
HI 7006M pH 6.86 solution, 230 mL bottle
HI 7007M pH 7.01 solution, 230 mL bottle
HI 7009M pH 9.18 solution, 230 mL bottle
HI 7010M pH 10.01 solution, 230 mL bottle
HI 7061M Electrode cleaning solution, 230 mL bottle
HI 70300M Electrode storage solution, 230 mL bottle
HI 710005 12VDC power adapter, US plug
HI 710006 12VDC power adapter, European plug
HI 710012 12VDC power adapter, Australian plug
HI 710013 12VDC power adapter, Southern Africa plug
HI 710014 12VDC power adapter, UK plug
(*) To be replaced by technical personnel only
To turn the meter off
Press the MODE button while in normal measurement mode.
OFF will appear on the lower part of the display. Release
the button. The display still lit, until the power supply is
connected.
Notes:
• Before taking any measurement make sure the meter
has been calibrated.
• To clear a previous calibration, press the MODE button
after entering the calibration mode. The lower LCD will
display ESC for 1 second and the meter will return to
normal measurement mode. The CAL symbol on the LCD
will disappear. The meter will be reset to the default
calibration.
• If measurements are taken in different samples succes-
sively, rinse the electrode thoroughly to eliminate
cross-contamination; and after cleaning, rinse the electrode
with some of the sample to be measured.
CALIBRATION