15
14
PROBE MAINTENANCE
After every series of measurements, rinse
the probe with tap water.
If a more thorough cleaning is required,
remove the sleeve and clean the probe
with a cloth or a nonabrasive detergent.
After cleaning the probe, always
recalibrate the instrument.
The 4-ring platinum probe body is made
of glass. For this reason great care while
handling the probe must be taken.
• Immerse the probe into a solution sample and adjust the
Temp. Coefficient knob to 0% (no compensation).
• Condition sample and probe at 25°C, and note the conductivity
reading C
25
.
• Condition sample and probe to a temperature t°C (approximately
5°C to 10°C different from 25°C), and note the conductivity
reading C
t
.
• The temperature coefficient (β) of the solution is then calculated
using the following formula:
β = 100 x (C
t
- C
25
) / [(t - 25) x C
25
]
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:
• Immerse the probe into the test solution and turn the
Temp. Coefficient knob to 0% (no compensation).
• 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.
• Repeat the procedure with a different solution temperature,
changed by more than 10°C. Wait for the reading to stabilize.
• Adjust the Temp. Coefficient knob until the display reads the
previously recorded C value.
• The value indicated by the knob is the temperature coefficient of
the solution.
DETERMINATION OF THE TEMPERATURE
COEFFICIENT OF A SOLUTION (HI 2315)
To Next Page
Loading...
