ACCESSORIES
HI 1286
Double junction, plastic body pH electrode with 2
m (6.6’) cable and BNC connector
HI 7634*
TDS probe with 2 m (6.6’) cable
HI 70004P
pH 4.01 solution, 20 mL sachet (25 pcs)
HI 7004M
pH 4.01 solution, 230 mL bottle
HI 70007P
pH 7.01 solution, 20 mL sachet (25 pcs)
HI 7007M
pH 7.01 solution, 230 mL bottle
HI 70010P
pH 10.01 solution, 20 mL sachet (25 pcs)
HI 7010M
pH 10.01 solution, 230 mL bottle
HI 70032P
1382 ppm solution, 20 mL sachet (25 pcs)
HI 7032M
1382 ppm solution, 230 mL bottle
HI 70442P
1500 ppm solution, 20 mL sachet (25 pcs)
HI 70442M
1500 ppm solution, 230 mL bottle
HI 70300M
Storage solution, 230 mL bottle
HI 700661P
Cleaning solution, 20 mL sachet (25 pcs)
HI 7061M
Cleaning solution, 230 mL bottle
HI 710005
115 Vac / 12 Vdc power adapter
HI 710006
230 Vac / 12 Vdc power adapter
HI 731326
Calibration screwdriver (20 pcs)
*
To be replaced by authorized technical personnel only
TAKING MEASUREMENTS
• Turn the meter on by connecting the supplied 12 Vdc
power adapter to the meter and then to the mains.
• Remove the protective cap
from the pH electrode.
• Immerse the tips of pH elec-
trode (at least 4cm/1½”),
TDS and temperature probes
into the solution to be tested.
For best accuracy, the probes
should not touch or stand
close to the vessel’s walls or
bottom.
• The three backlit LCDs will show
the pH, TDS and tempera-
ture values, respectively.
Any initial variation in readings may be due to the pH
electrode conditioning and to the temperature compensa-
tion of TDS measurements. Allow the readings to stabilize.
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. Always replace the protective cap after use.
DO NOT USE DISTILLED OR DEIONIZED WATER FOR STOR-
AGE PURPOSES.
• If the electrode has been left dry, soak the tip in
HI 70300
storage solution overnight to reactivate it.
• To minimize clogging and provide longer life for the pH
electrode, it is recommended to clean it at least once a
week. Immerse the tip of the electrode in the
HI 700661
cleaning solution supplied with the instrument, for half an
hour and then rinse it with tap water.
TDS PROBE MAINTENANCE
It is recommended to clean the probe at least once a month,
by following this procedure:
• Immerse the tip of the probe in the
HI 700661
cleaning
solution supplied with the instrument, for half an hour.
• If a more thorough cleaning is required, brush the metal
pins with very fine sandpaper.
• After cleaning, rinse the probe with tap water and recalibrate
the instrument.
pH CALIBRATION
Pour small quantities of pH 7 (
HI 7007
) and pH 4 (
HI 7004
)
or pH 10 (
HI 7010
) buffer solutions into two clean beakers.
For accurate calibration use two beakers for each buffer solu-
tion, the first one for rinsing the electrode tip, and the second
one for calibration.
• Turn the meter on.
• Remove the electrode protective cap, rinse and immerse the
electrode in the pH 7 buffer solution together with the TDS
probe (working as matching pin). Stir gently and wait for
the reading to stabilize.
Note:
The electrode should be submerged approximately 4 cm
(1½”) in the solution.
• Adjust the “pH 7” trimmer with the supplied calibration
screwdriver until the LCD shows pH “7.0”.
•
Rinse and immerse the pH electrode and the TDS probe in
the pH 4 (or pH 10) buffer. Stir gently.
• Wait for a stable reading and then adjust the “pH 4”
trimmer to read pH “4.0” (or pH “10.0”).
The pH calibration is now complete.
TDS CALIBRATION
• Turn the meter on.
• Pour a small quantity of the proper calibration solution (HI
7032
for
HI 981504/5
or
HI 70442
for
HI 981504/7
) in a
beaker. If possible, use plastic beakers to minimize any EMC
interference.
• Immerse the TDS probe in the solution, making sure that
the metal pins are completely submerged.
Note:
For best accuracy, the probe body should not touch nor
stand close to the side walls of the beaker.
• Wait for a couple of minutes for thermal equilibrium to be
reached and the temperature to be compensated.
• Tap the probe gently on the bottom and shake it, to make
sure no air bubbles have remained trapped inside.
• Adjust the calibration trimmer with the supplied screwdriver
until the display shows “1380” ppm (
HI 981504/5
) or
“1500” ppm (
HI 981504/7
)
Calibration is now complete.
CE DECLARATION OF CONFORMITY
ISTCOMBO3-R1 05/05
pH ELECTRODE CONNECTION
In order to protect the instrument against vapors
and humidity, the BNC connector is protected with
a waterproof sheath.
• Slide the protective sheath down. Connect the
pH electrode to the BNC socket and then slide
the protective sheath back up. For maximum
waterproof protection, make sure the connector
is completely covered.
• Do not be alarmed if white crystals appear around the
electrode protective cap. This is normal with pH electrodes
and they dissolve when rinsed with water.
°C/°F SELECTION
• The user can easily select the temperature unit, in degrees
Celsius (default) or Fahrenheit through a switch on the rear
panel.
• Remove the label and set the switch to the desired position.
Replace the label for better protection against humidity.
