Freeze-dryer Gamma 1-16 LSCplus
Freeze-dryer Gamma 2-16 LSCplus
6 Operation
Version 04/2013, Rev. 2.10 of 09/03/2020
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Translation of the original operating manual
6.6
Optional extensions
Pressure increase test
see also chapter 6.5.3.1 - "Creating a program", button ">>more"
The pressure increase test can only be carried out with the
→
double-
chamber method.
During the pressure increase test, the intermediate valve
prevents the flow of steam from the drying chamber to the ice condenser so
that the water vapour of the
→
sublimation
cannot flow off. The result is a
more or less distinct pressure increase that is measured in the product
chamber. The pressure increase test is used as a criterion for the automatic
switching between main drying and final drying and also for identifying the
end of the process.
Comparative pressure measurement
see also chapter 6.5.3.1 - "Creating a program", button ">>more"
During the sublimation, i.e. when the concentration of water vapour
molecules is rather high in the atmosphere, the value that is provided by
the gas-type-dependent vacuum sensor of the "Pirani" type (e.g. Thyracont
VSP62/63) deviates from the value that is provided by a capacitive vacuum
sensor (e.g. MKS 722B). When the proportion of water vapour molecules
decreases towards the end of the main drying phase, the two sensors fall
increasingly in line with one another. This difference will be evaluated and
used as an indicator for identifying the drying end of the main drying phase.
Leakage test
see also chapter 6.5.2.1 - "Entering set values in the manual mode"
The leakage test enables the chamber of the freeze-dryer to be tested for
tightness in view of any gaseous or liquid media. Since absolutely tight
components simply do not exist, a leak rate is determined. The parameters
for the leakage test have been developed by Martin Christ Gefrier-
trocknungsanlagen specifically for freeze-dryers. In a first step, these
parameters (vacuum, ice condenser temperature) must be reached. It is not
until the conditions are fulfilled that the pressure control valve closes. Then,
the actual leakage test is performed in a second step. The leak rate that is
calculated after the end of the test provides information concerning the
tightness of the system.
PGMplus programmer module
see also chapter 6.5.3 - "Option: freeze-drying with the PGMplus
programmer module"
The PGMplus programmer module enables the fully automatic execution of
an entire freeze-drying process under reproducible conditions.
USB process recorder
see also chapter 6.5.2 - "Manual freeze-drying", dialog box "Tools"
This feature enables the recording of a running process on a USB storage
medium. After the end of the process recording, the process data can be
viewed on the PC with LyoLogplus and be printed. It is also possible to
import the data directly into an Excel file.
