Note: when leaving calibration mode the value on the display may increase
or decrease. This happens only if the temperature of the liquid is different
from 20°C (25°C) (which is the temperature at which the conductivity values
are normalized). In fact, when the temperature is different from 20°C (25°C)
the instrument indicates the conductivity value with the temperature com-
pensation made according to the
α
T
coefficient, set by the user, which may
be considerably different from the value of the calibration solution.
f) Rinse the probe in water. If measurements are later made at low con-
ductivity, we advise rinsing it in distilled or bidistilled water.
At this point the instrument is calibrated and ready for use.
MANUAL CALIBRATION
Manual calibration is possible using solutions with any conductivity. Howe-
ver it is necessary to know the conductivity of the solution at the tempera-
ture at which calibration is to be carried out. Follow these instructions:
a) Immerse the conductimetry cell in the solution with known conductivity
so that the electrodes are covered with liquid. Switch on the instrument
by pressing the ON/OFF key.
b) Press the
α
T
key. The temperature coefficient used for calculating the
temperature compensation in conductivity measurements is displayed.
Using the
2
key, bring the value displayed to 0.00. In this way the tem-
perature compensation in conductivity measurement is excluded.
c) Take the temperature reading by pressing the °C/°F key. On the basis of
the temperature determine the conductivity of the calibration solution, for
example by looking it up in a table that indicates conductivity as a func-
tion of temperature.
d) Press the
key. Press the CAL key. The µS (or mS) symbol flashes. If
the conductivity of the calibration solution is close to that used in auto-
matic calibration, the instrument proposes this value. Using the
1
and
2
keys, set the conductivity value determined at point c. If the conducti-
vity of the calibration solution is very different from the one used in auto-
matic calibration, “E1” (slope >150% of the rated value) or “E2” (slope
<30% of the rated value) is displayed. In both cases it is sufficient to
press the
1
or
2
key to cancel the error signal. Using the same keys,
set the conductivity value determined at point c.
ENGLISH
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