Titration sequence for kft – Metrohm 840 PC Control 5.0 / Touch Control User Manual
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Parameters
PC Control / Touch Control
215
adapted to the size of the titration cell in order to prevent any over-
flow.
• Cond. stop time: If conditioning takes longer than the time entered
here then the process will be stopped.
• Start reconditioning only at end of method: If this option is
switched on then reconditioning will only start when all method
commands have been processed. Otherwise reconditioning would
start immediately after the titration command. This function must be
activated if other commands follow the KFT command that must not
be allowed to take place at the same time as conditioning. Exam-
ple: emptying the titration cell and then adding new solution.
The parameters for Control device, Sensor, Dosing device and
Stirrer
are described in Section 4.1.5.
Titration sequence for KFT
1st start of titration
command
Checks whether work is to be carried out with or
without conditioning.
(Switch on stirrer)
The stirrer is switched on after the start.
Preconditioning
(if activated)
The titration cell solution is titrated to the end-
point and kept there continuously.
2nd start of titration
command
The method sequence itself starts.
Measure initial meas-
ured value
The initial measured value is measured.
(Start conditions:
Pause 1
Start volume
Pause 2)
Pause interval 1 is allowed to elapse. The start
volume is added. No measuring points are en-
tered in the list of measuring points. Pause inter-
val 2 is allowed to elapse.
(Extraction time)
Titration with test up
to stop when stop
criterion or the stop
condition is reached
Titration is carried out.
If the extraction time has not elapsed when the
endpoint has been reached then it will be al-
lowed to elapse and the titration will only be
concluded when the extraction time has
elapsed.
(Switch off stirrer)
The stirrer is switched off if there is no recondi-
tioning.
Fill dosing
cylinder
After the end of the titration the dosing cylinder is
refilled automatically.
Post-conditioning
The titration cell solution is kept continuously at
the endpoint.
Optional steps are shown in brackets.