Drying Monitoring; Figure 24: Schematic Timing Of The Drying Process And Drying Monitoring - Binder VDL Series Operating Manual

11.6 Drying monitoring

Pressure


Figure 24: Schematic timing of the drying process and drying monitoring

Procedure:
• Enter the temperature set-point.
The previously entered pressure setpoint is not used with this function. It remains saved.
The drying monitoring uses a fixed minimum pressure setpoint.
• Start the drying monitoring: the vacuum pump is activated, the evacuation valve opens.
Starting from ambient pressure, the pressure starts to decrease.
• Depending on the vapor pressure of the solvent, a plateau phase is then reached
solvent vaporizes. The pressure remains almost constant.
• After the solvent is completely evaporated, drying is complete.
again
Without drying monitoring the pressure would now continue to decrease

vacuum is reached.
• The drying monitoring recognizes this second pressure drop. It turns off the pressure control. The
chamber will then be ventilated automatically
Prior to starting a new drying process, the pressure control must be activated again (chap. 11.4).
Notes:
If the drying monitoring is aborted during phase
sure value as the pressure setpoint. This overwrites the previously entered pressure setpoint. It can be
changed manually at any time.
In processes with low temperatures < 40 °C or thermally poorly coupled items to be dried (e.g. drying of
powders), the drying monitoring may incorrectly identify the relevant parameters. In this case, please
check the process result and, if necessary, use a process not including this program for such processes.
VDL (E3.1) 06/2020
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. 
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or
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Time
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The pressure starts to decrease
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,
the controller will take the current actual pres-
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during which the
, until the maximum final
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