Metrohm 900 - Endpoint Titration (SET); Water Determination According to Karl Fischer (KFT); Figure 5 Reagent Dosing for SET

5.3 Endpoint titration (SET)
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900 Touch Control
5.3 Endpoint titration (SET)
Endpoint titration is a titration mode for rapid routine determinations to a
preset endpoint (e.g. titrations in accordance with special standards) and
titrations for which reagent overflow must be avoided. The titration termi-
nation at the endpoint takes place either volume drift-controlled or after a
waiting time. The volume dosed until the endpoint can be used for further
calculations (e.g. the content of the sample).
t/s
Continuous
dosing
Initial
dosing
V/mL
V/mL
U/mV
Endpoint
Control range
Figure 5 Reagent dosing for SET
5.4 Water determination according to Karl Fischer (KFT)
Karl Fischer Titration is a method for volumetric water determination. Con-
ditioning is carried out automatically both before and after the actual titra-
tion. The reagent dosing is controlled in such a way that a predefined end-
point is reached as quickly and as accurately as possible. The volume steps
and the rate of reagent dosing are regulated by the difference between
the current measured value and the predefined endpoint. This means that
titration is performed more slowly in the control range and that smaller
volumes are added. The titration is stopped at the endpoint either drift-
controlled or after a waiting time. The volume dosed until the endpoint is
used to calculate the water content of the sample.