horiba LAQUAact D-74, Инструкция по эксплуатации

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Checking and calibrating the conductivity cell
70 HORIBA
●
Checking and calibrating the conductivity cell
If the conductivity cell is used for a long period, the cell constant gradually changes. For
this reason, check the conductivity cell about once every three months.
If the result of the check is a deviation of 5% or higher, calibrate the conductivity cell.
1. Prepare potassium chloride standard solution to be used for checking and
calibrating the conductivity cell. Dry potassium chloride powder for at least two
hours at 105°C and let cool in a desiccator.
The concentration of the standard solution varies depending on the conductivity cell
that is used. Refer to the table below.
2. Prepare the standard solution to use the cooled potassium chloride powder as
explained above.
3. Wash the conductivity cell with pure water (or
deionized water) and wipe it with filter paper or
tissue paper.
Do not touch the black electrode part.
4. Immerse the conductivity cell in the prepared standard solution, and read the
measured value. If there is a difference of 5% or more between the conductivity
of the standard solution and the measured value, perform calibration to use the
standard solution.
If the difference is less than 5%, calibration is not currently needed.
Cell
constant
model
KCl
solution
Temp.
Conductivity
value
KCl
weight
preparative
method
1000 m
-1
(10 cm
-1
)
3553-10D 0.1 mol/L 25°C
1.286 S/m
(12.86 mS/cm)
7.4365 g
Dissolve the
weighed KCI,
pour into a 1L
measuring
flask, and add
pure water (or
deionized
water) up to the
marked line.
100 m
-1
(1 cm
-1
)
3552-10D
9382-10D
0.01 mol/L 25°C
140.9 mS/m
(1.409 mS/cm)
0.7440 g
10 m
-1
(0.1 cm
-1
)
3551-10D 0.001 mol/L 25°C
14.7 mS/m
(147 µS/cm)
－
Pour 100 mL of
the 0.01mol/L
standard
solution into a
1L measuring
flask, and add
pure water (or
deionized
water) up to the
marked line.