Additional measured values – Metrohm tiamo 1.1 Manual User Manual
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Method
Minimum evaluation
on, [ off ]
For the minimum measured value the associated volume, time and tem-
perature are interpolated from the list of measuring points (see Titration
commands - Evaluation - Minimum/maximum evaluation).
Threshold value
0.5 ... [ 5.0 ] ... 10.0 µA/mL
The evaluation begins as soon as the slope of the curve exceeds the set
threshold value.
Maximum evaluation
on, [ off ]
For the maximum measured value the associated volume, time and tem-
perature are interpolated from the list of measuring points (see Titration
commands - Evaluation - Minimum/maximum evaluation.
Threshold value
0.5 ... [ 5.0 ] ... 10.0 µA/mL
The evaluation begins as soon as the slope of the curve exceeds the set
threshold value.
Additional measured values
Screenshot and parameters: see DET pH - Additional measured values
KFT
Command for volumetric Karl Fischer Titrations (
KFT
).
Principle
With this command volumetric titration for determining the water content by the
Karl Fischer method with automatic pre- and post-conditioning are carried out. A
typical feature of the Karl Fischer titration is the controlled reagent addition, which
depends on the control difference (current measured value – endpoint), with the
aim of reaching the measured value given as being the predefined target endpoint
as quickly and accurately as possible. Overtitrating is avoided to a great extent.
The titration termination at the endpoint takes place either drift-controlled or after a
waiting period. The volume added up to the endpoint gives the calculable reagent
consumption
Reagent addition takes place in three phases during the titration:
• Initial addition
During this phase the dosing rate increases continuously. It starts with
the
Min. rate
and increases to the
Max. rate
.
• Continuous addition
Addition is carried out at the
Max. rate
until the
Control range
is
reached.
• Control range
In this range addition is finely controlled. Shortly before the endpoint is
reached addition is only carried out at the
Min. rate
.