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Operation
Dynamic AUTOaccurate (DAA) mode
In Dynamic AUTOaccurate (DAA) mode, the vacuum pressure is controlled depending on the
temperature.
System requirements
For operation in Dynamic AUTOaccurate (DAA) mode, the device has to
be equipped with an optional AUTOaccurate sensor.
The AUTOaccurate sensor can only be used in combination with glass-
ware G3 or G6!
The temperature-dependent vacuum control in DAA mode is based on two values:
–
[Condenser temperature]: Temperature reading on the AUTOaccurate sensor in the
condenser
–
[Intensity]: Relative temperature rise to the closing of the vacuum valve, based on the
measured condenser temperature T(AA)
At the start of the process, the condenser temperature T(AA) is measured using the
AUTOaccurate sensor. When reaching a stable level, the actual evaporation process starts.
This "pre-process" can be manually canceled at any time. In this case, the evaporation process
is started immediately with the currently measured condenser temperature value.
During the evaporation process, the temperature at the AUTOaccurate sensor increases
relative to the initial condenser temperature T(AA). If this temperature rise reaches the defined
intensity (parameter [Intensity]), the evaporation process is stopped.
As soon as the temperature at the AUTOaccurate sensor has dropped by a defined value, the
system is evacuated and the evaporation process starts again. If the temperature rise at the
AUTOaccurate sensor reaches the defined intensity again (at relatively higher vacuum pres-
sure), the vacuum pump is switched off again, etc.
In this way, a consistent performance is achieved in the processing of solvents or mixtures
throughout the distillation process.
During multiple solvent distillation, the described process steps are repeated until a defined
maximum vacuum pressure is reached (input value [End pressure]). The distillation process is
then switched off.
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