Metrohm 899 Coulometer - Manual (Page 90)

7.1 Coulometric Karl Fischer titrations (KFC)
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80 ￭￭￭￭￭￭￭￭
899 Coulometer
Selection 100 mA | 200 mA | 400 mA | auto
Default value 400 mA
400 mA
default value, when Generator electr. = w/o diaphr.
auto
The current is adapted to the conductivity of the reagent and automat-
ically reduced near the endpoint. Default value, when Generator
electr. = with diaphr.
Stirrer
The stirrer is switched on at the start of the determination when this para-
meter is activated.
Selection on | off
Default value on
Stirring rate
Setting the stirring rate. It can be set in steps of –15 to +15. The default
setting 8 corresponds to 1000 rpm. The formula for calculating the rota-
tional speed is specified in chapter 10.1, page 92. The optimum stirring
rate can be tested in the manual control.
The algebraic sign changes the direction in which the stirring is done.
When viewing the stirrer from above, this means:
￭ "+": counterclockwise rotation
￭ "–": clockwise rotation
Input range –15 ... 15
Default value 8
I(pol)
The polarization current is the current that is applied to a polarizable elec-
trode during the voltametric measurement.
Selection 5 µA | 10 µA | 20 µA | 30 µA
Default value 10 µA
Note
Note that the parameter I(pol) is linked with the parameters Dynamics
and Endpoint at. Explanations in this connection can be found in
chapter 10.4 Control parameters and polarization current, page 95.