• If measurements are taken in different samples suc-
cessively, rinse the probe tip thoroughly with wa-
ter and then with some of the next sample to be
measured.
Calibration Buffer Set Selection
• While in 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 4.01/7.01/10.01)
or “pH 6.86 BUFF” (for 4.01/6.86/9.18).
• Press SET/HOLD to change the buffer set.
• Press MODE to return to normal pH mode.
pH Calibration
• While in 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).
• For a single point pH calibration, place the
probe in any buffer from the selected buffer set
(eg. pH 4.01 or pH 7.01 or pH 10.01). The meter
will automatically recognize the buffer value.
If using pH 7.01 (or pH 6.86 from the NIST buffer
set), after recognition of the buffer press MODE to
return to the pH measurement mode.
• For a two point pH calibration, place the probe
in pH 7.01 (or pH 6.86, if you have selected the
NIST buffer set). The meter will recognize the buffer
value and then display “pH 4.01 USE”.
• Place the probe in the second buffer (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 dis-
play “OK” for 1 second and the meter will return to
normal measurement mode.
To Clear Previous Calibrations, 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”
tag on the LCD will disappear and the meter will be
reset to the default calibration.
EC/TDS MEASUREMENTS & CALIBRATION
• Place the probe in the sample to be tested. Use
plastic beakers or containers to minimize any elec-
tromagnetic interference.
• Select either EC or TDS mode with the SET/HOLD
button.
• Tap the probe lightly on the bottom of the container
to remove air bubbles that may be trapped inside
the tip.
• Wait for a few minutes for the temperature sensor to
reach thermal equilibirium (i.e. until the stability
indicator on the top left of the LCD disappears).
• The meter will show the EC or TDS value auto-
matically compensated for temperature, and the
temperature of the sample.
Selection of the TDS Conversion Factor
(CONV) and Temperature Coefficient (BETA)
• While in EC or TDS 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
conversion factor (e.g. 0.50 CONV).
• Press the SET/HOLD button to change the value.
• Press the MODE button to show the current tem-
perature compensation coefficient (e.g. 2.1 BETA).
• Press the SET/HOLD button to change the value.
• Press MODE to return to normal operation.
EC Calibration
• While in the 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
HI 7031 calibration solution (“µS 1413 USE”).
• Once the calibration has been automatically per-
formed, the LCD will display “OK” for 1 second
and return to normal measurement mode.
• Since there is a known relationship between
the EC and TDS reading, it is not necessary
to calibrate the meter in TDS. If the TDS con-
version factor is either 0.5 or 0.7, the meter
will allow a direct calibration in ppm by us-
ing the Hanna TDS calibration solutions (see
“Accessories” section).
OPERATIONAL GUIDE
• Connect the HI 1288 probe to the DIN socket
on the top of the meter by aligning the pins and
pushing in the plug. Tighten the nut to ensure a
good connection. Remove the protective cap from
the probe before taking any measurement.
• Press and hold the MODE button for 2 seconds. All
the used segments on the LCD will be visible for a
few seconds, followed by a percent indication of
the remaining battery life (e.g. % 100 BATT).
• Select the measurement range (pH, EC or
TDS) by pressing the SET/HOLD button while in
normal measurement mode. The meter will dis-
play the pH, EC or TDS value on the primary
LCD, while temperature will be simultaneously dis-
played on the bottom (e.g. pH 5.73 and 22.5 °C).
• To change the temperature unit (from °C to
°F), press and hold the MODE button until “TEMP”
and the current temperature unit are displayed on
the secondary LCD (e.g. TEMP °C). Then use
SET/HOLD to change the temperature unit, and
press the MODE button until the meter returns to
normal measurement mode.
• To freeze the display, press and hold SET/HOLD
until “HOLD” appears on the secondary display
(e.g. pH 5.73 hold). Press either button to return to
normal mode.
• To turn the meter off, press and hold the MODE
button while in normal measurement mode. “OFF”
will appear on the lower part of the display. Re-
lease the button.
pH MEASUREMENT & CALIBRATION
• Before taking any measurement make sure the
meter has been calibrated.
• If the probe has been left dry, soak in a storage or
pH 7 solution at least for one hour to reactivate it.
• Select the pH mode with the SET/HOLD button.
• Submerge the probe in the sample to be tested
while stirring it gently. Wait until the stability indica-
tor on the top left of the LCD disappears.
• The pH value automatically compensated for tem-
perature is shown on the primary LCD, while the
secondary LCD shows the sample temperature.
BATTERY REPLACEMENT
The meter displays the remaining battery percent-
age every time it is turned on. When the battery level
is below 5%, the low battery indicator on the bottom
left of the LCD lights up to warn the user. If the battery
level is low enough to cause erroneous reading, the
Battery Error Prevention System (BEPS) will auto-
matically turn the meter off.
To change the batteries, remove the 4 screws lo-
cated on the back of the meter and carefully replace
the four AAA batteries, while paying attention to their
polarity. Replace the back and tighten the screws,
while checking that the gasket is in place to ensure a
watertight seal.
ACCESSORIES
HI 1288
pH/conductivity probe with built-in
temperature sensor, DIN connec-
tor and 1 m (3.3’) cable
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 7010P
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 710007
Blue shockproof rubber boot
HI 710008
Orange shockproof rubber boot
IST99130X 07/05
