Preliminary operations
Connect the pH electrode to the meter.
Connect the 12 Vdc 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 (E.g. 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
Select the pH, EC or TDS mode with the SET/HOLD button.
Immerse the probes in the solution to
be tested. In order to ensure better
accuracy, probes should not touch or
stand close to the walls or bottom of
the sample vessel.
The pH, EC or TDS value automatically
compensated for temperature is shown
on the primary LCD while the second-
ary LCD shows the temperature of the
sample.
Measurements should be taken when the stability symbol on
the top left of the LCD disappears.
IMPORTANT NOTE
Measurements have to be taken with both pH elec-
trode and conductivity/temperature probe (also
working as matching pin) immersed in the same
vessel.
OPERATIONAL GUIDE
CALIBRATION
pH calibration buffer set
• From pH measurement mode, press and hold the MODE
button until “TEMP” and the current temperature unit are
displayed on the lower LCD (E.g. TEMP °C).
• Press the MODE button again to show the current buffer
set: “pH 7.01 BUFF” for standard set (for pH 4.01/7.01/
10.01) or “pH 6.86 BUFF” for NIST buffer (pH 4.01/
6.86/9.18).
• Press the SET/HOLD button to change the buffer value.
• Press MODE to return to normal measuring mode.
pH calibration procedure
From pH 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 probe in any buffer from the selected buffer set (e.g.
pH 7.01, 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 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 and immerse it in the
second buffer solution (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 normal measurement 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 cali-
brated.
pH ELECTRODE MAINTENANCE
• When not in use, rinse the electrode with water and store
it with a few drops of
HI 70300
storage solution in the
protective cap.
NEVER USE DISTILLED OR DEIONIZED WATER FOR STORAGE
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
Spare pH electrode with differential input & DIN
HI 7630 (*)
Conductivity probe with built-in temperature sen-
sor (also working as matching pin)
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 7030M
12.88 mS/cm solution, 230 mL bottle
HI 7031M
1413 µS/cm solution, 230 mL bottle
HI 7032M
1382 ppm solution, 230 mL bottle
HI 7038M
6.44 ppt solution, 230 mL bottle
HI 70442M
1500 ppm solution, 230 mL bottle
HI 7061M
Electrode cleaning solution, 230 mL bottle
HI 70300M
Electrode storage solution, 230 mL bottle
HI 710005
115 Vac/12 Vdc power adapter, US plug
HI 710006
230 Vac/12 Vdc power adapter, European plug
(*)
To be replaced by authorized technical personnel only.
To change the TDS conversion factor (CONV) and the
temperature compensation coefficient
β
(BETA)
• From measurement mode, press and hold the MODE
button until “TEMP” and the current temperature unit are
displayed on the lower LCD (E.g. TEMP °C).
• Press the MODE button again to show the current conver-
sion factor (E.g. 0.50 CONV).
• Use the SET/HOLD button to change the conversion factor.
• Press the MODE button to show the current temperature
coefficient (E.g. 2.1 BETA).
• Use the SET/HOLD button to change the value.
• Press MODE to return to normal measuring mode.
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 lits, 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 successively,
rinse the probes thoroughly to eliminate cross-contamina-
tion; and after cleaning, rinse the probes with some of the
sample to be measured.
EC calibration procedure
• From EC measurement mode, press and hold the MODE
button until “CAL” is displayed on the lower LCD.
• Release the button and immerse the probe in the proper
calibration solution:
HI
70031
(1413 µS/cm) for
HI
991404
and
HI 70030
(12.88 mS/cm) for
HI 991405
.
• Once the calibration has been automatically performed,
the LCD will display “OK” for 1 second and the meter will
return to normal measurement mode.
•
Since there is a known relationship between EC and
TDS readings, it is not necessary to calibrate the TDS
range.
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 cali-
brated.
