Conductivity: Determining the cell constants
Multi 340i
10
Conductivity: Determining the cell constants
Procedure
The cell constants are determined in the control standard 0.01 mol/l KCl.
Calibration
evaluation
After the calibration, the measuring instrument automatically evaluates the
current status of the calibration. The evaluation appears on the display.
Procedure for determining the cell constants:
Display
Cell constant [cm
-1
]
0.450 ... 0.500 cm
-1
E3
Invalid calibration
Outside the range
0.450 ... 0.500 cm
-1
l
Connect a conductivity measuring cell to the measuring instrument.
If necessary, press the <M> key repeatedly until the status display
(conductivity measurement) appears.
l
Press the <CAL> key. Depending on the calibration status, the
CAL
display appears as well as:
– the current, calibrated cell constant (with sensor symbol on the
display) or
– the fixed cell constant 0.475 1/cm (without sensor symbol on the
display). In this case, the measurement parameters are initialized.
Note
At this point, the procedure can be terminated with <M>.
l
Immerse the conductivity measuring cell in the control standard solution,
0.01 mol/l KCI.
l
Press <RUN/ENTER>. The AutoRead measurement begins.
l
When the measured value is stable, the instrument displays the deter-
mined cell constants and the calibration evaluation. The measuring in-
strument automatically stores the cell constants.
l
Switch to the measuring mode with <M>.
2
0 7
4
Cal
cm
1/
Tref25
A L
C
3
0 7
4
Cal
cm
1/
Tref25
A L
C
