User's Manual

1.51

0.5

TEMPERATURE COEFFICIENT

DETERMINATIONDETERMINATION

DETERMINATION

OFOF

THETHE

THE

TEMPERATURETEMPERATURE

TEMPERATURE

COEFFICIENT OF A SOLUTIONCOEFFICIENT OF A SOLUTION

COEFFICIENT OF A SOLUTION

(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.