Metrohm 900 - Titration with Constant Maintenance of the Measured Value (STAT); Figure 6 Reagent Dosing for KFT

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5 Titrations
900 Touch Control
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13
EP
KFT Ipol
KFT Upol
EP
V/mL
Continuous
dosing
Initial
dosing
V/mL
V/mL
U/mV
t/s
I/µA
Control range
Control range
Figure 6 Reagent dosing for KFT
5.5 Titration with constant maintenance of the mea-
sured value (STAT)
In STAT titrations, reagent is added until a preset measured value (control
point) has been reached, which is then maintained at a constant level.
Because the substance that is released as a result of the reaction is imme-
diately titrated off with the titrant, the STAT controller has to be able to
maintain a preset control point at a constant level until the preset stop
condition has been reached, i.e. without oscillating around the control
point.
STAT titrations are used, for example, in enzyme analysis where the
enzyme activity can be determined from the resulting dosing rate (in
mL/min).
Reagent dosing takes place in two phases during the titration:
￭ Dosing outside the control range
The dosing rate increases continuously during this phase. It starts with
the Min. rate and increases to the Max. rate. The dosing continues to
be carried out at the Max. rate until the Control range is reached. In
this range, STAT mode and SET mode control equally.