Delta OHM HD 8706-R1, Instruction Manual

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ENGLISH
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3.1 AUTOMATIC CALIBRATION
Automatic calibration is possible with a 0.1-mole (or 0.01-mole) solution of
KCI. The temperature of the solution must be between 15°C (59°F)
and 30°C (86°F), otherwise the error signal “E3” appears.
a) Switch on the instrument by pressing the key.
b) Immerse the conductimetry cell in the sample solution so that the four
rings are covered.
c) Shake the electrode gently so that any air inside it will escape.
d) Press the CAL key. The conductivity value of the solution at the probe
temperature appears on the display. For example 1278 µS at 20°C
(68°F) and the µS (or mS) symbol flashes.
e) Press the CAL key again to confirm the value displayed (or adjust this
value with the
s
and
t
keys before pressing CAL again). The µS (or
mS) symbol stops flashing.
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 (which is the temperature at which the conductivi-
ty values are normalized). In fact, when the temperature is different
from 20°C the instrument indicates the conductivity, value with the tem-
perature compensation made according to the
α
T
coefficient, set by the
user, which may be considerably different from the value of the calibra-
tion 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.