98
air bubbles remain trapped in the sleeve.
• Record the temperature of the buffer solution from the thermom-
eter (e.g. 18°C).
• Switch the instrument on by pressing ON/OFF.
• Press COND/TEMP (HI 8633) or
TDS/TEMP (HI 8734) to display
the temperature.
• Adjust the TEMPERATURE knob to display 18°C.
• Press COND/TEMP (or TDS/TEMP)
again to display conductivity mea-
surement.
• Select 19.99 mS/cm (HI 8633)
or 1999 mg/L (HI 8734) range
by pressing the appropriate
range key.
• Remove the battery compartment cover and adjust the calibration
trimmer located inside with the calibration screwdriver until the
display shows for HI 8633 the conductivity reading at 25°C (see
the conductivity vs. temperature table), e.g. @ 25°C, 12880 µS/
cm = 12.88 mS/cm, or for HI 8734 the TDS reading at 25°C
(see the TDS vs. temperature chart), e.g. @25°C, 1382 mg/L.
ON
OFF
TEMPERATURE
COND.
TEMP.
TDS
TEMP.
COND.
TEMP.
TDS
TEMP.
19.99
mS
1999
mg/l
• Select the appropriate measurement range.
Note: If the display shows only a "1" on the
far left hand side, the meter is out of
range. Select the next (higher) range.
• Wait for a couple of minutes for the temperature sensor to reach
thermal equilibrium with the sample before taking measure-
ments.
• After the measurement has been completed, the instrument
should be switched off and the probe should be cleaned and
dried (see "Probe Maintenance" on page 15).
Accessories needed:
• Use any calibration solution within the meter's range. The
solution should ideally be close to the samples being mea-
sured. Use for example HI 7030 or HI 8030, 12880 µS/cm
(=12.88 mS/cm) conductivity solution, for HI 8633 and HI
8733, and HI 7032, 1382 mg/L (=2764 µS/cm) TDS
solution, for HI 8734.
• ChecktempC or another accurate thermometer with 0.1°C
resolution (not necessary for HI 8733).
• a small screwdriver.
PROCEDURE FOR HI 8633 AND HI 8734
• Pour sufficient quantity of a conductivity
(HI 8633) or TDS (HI 8734) calibration
solution (e.g. HI 7030 or HI 7032) into
a beaker to cover the holes on the probe.
If possible, use plastic beakers to mini-
mize any EMC interference.
• Immerse the conductivity probe, making
sure that holes are completely submerged,
and the ChecktempC in the solution.
• Wait for a couple of minutes for thermal
equilibrium to be reached.
• Tap the probe on the bottom, then
shake it while rotating to make sure no
CALIBRATION
HI 7030
°C
