Hanna Instruments HI 8819 User Manual
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1.5
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TEMPERATURE COEFFICIENT
DETERMINATION
DETERMINATION
DETERMINATION
DETERMINATION
DETERMINATION OF
OF
OF
OF
OF THE
THE
THE
THE
THE TEMPERATURE
TEMPERATURE
TEMPERATURE
TEMPERATURE
TEMPERATURE
COEFFICIENT OF A SOLUTION
COEFFICIENT OF A SOLUTION
COEFFICIENT OF A SOLUTION
COEFFICIENT OF A SOLUTION
COEFFICIENT OF A SOLUTION
(for HI8820 only)
(for HI8820 only)
(for HI8820 only)
(for HI8820 only)
(for HI8820 only)
Follow the procedure described below:
1) Immerse the probe into a sample of the solu-
tion and adjust the knob to 0% (i.e. no
compensation).
2) Condition the sample and probe at 25°C
and note the conductivity reading C25.
3) Condition the sample and probe to a tem-
perature t°C which is approximately 5°C to
10°C different from 25°C and note the conductivity reading Ct.
4) The temperature coefficient ß of the solution is calculated with
the formula:
(Ct - C25)
ß = 100 x ---------------------------
(t - 25) x C25
The above procedure is suitable for determining the temperature
coefficient in the laboratory where the temperature of the solution
can be determined and controlled. If this is not possible e.g.
during on-site measurements, the following procedure should be
used:
a) Immerse the probe into the test solution and turn the temperature
coefficient knob to 0% (no compensation).
b) Allow the conductivity reading to stabilize (the reading should not
change by more than ±0.2 mS within 1 minute) and record the
value, C.
c) Repeat the procedure with the temperature of the solution changed
by more than 10°C. Wait for the conductivity reading to stabilize.
d) Adjust the temperature coefficient knob until the display reads the
value C as recorded earlier (point b).
e) The value indicated by the knob is the temperature coefficient of
the solution.