Metrohm tiamo 2.4 Manual - Manual (Page 799)

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5 Method
tiamo 2.4
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5.6.3.4.6.10 SET Upol - Fixed endpoint evaluation
Dialog window: Method ▶ SET Upol ▶ Properties... ▶ Additional evalua-
tions ▶ Fixed endpoint evaluation ▶ [New/[Properties] ▶ Fixed endpoint evalua-
tion #
Quantity
Selection of the fixed measured quantity to which the associated values
for the other quantities are to be interpolated from the list of measured
points.
Selection Measured value | Time | Volume
Default value Measured value
Fixed value
Value of the fixed endpoint.
Measured value
Input range
-200.0 - 200.0 µA
Time
Input range
0.0 - 999999.9 s
Volume
Input range
0.00000 - 9999.99 mL
5.6.3.5 KFT
5.6.3.5.1 KFT - Overview
Menu item: Method ▶ Insert ▶ New command...
Command for volumetric Karl Fischer titrations.
Principle
Volumetric titrations for determining the water content according to Karl
Fischer with automatic conditioning are carried out with this command. A
typical feature of the Karl Fischer titration is the controlled reagent dosing,
which depends on the control difference (current measured value – end-
point), with the aim of reaching the measured value given as being the
predefined target endpoint as quickly and accurately as possible. Overti-
trating is avoided to a great extent. The titration termination at the end-
point takes place either drift-controlled or after a waiting period. The vol-
ume added up to the endpoint gives the calculable reagent consumption.
Reagent dosing takes place in three phases during the titration:
￭ Initial dosing
The dosing rate increases continuously during this phase. It starts with
the Min. rate and increases to the Max. rate.