Martin Christ Alpha 1-2 LDplus - Manual (Page 68)

Freeze-dryer Alpha 1-2 LDplus
11 Appendix
68
Version 11/2006, Rev. 2.0 of 02/12/2014 • sb
Translation of the original operating manual
Step-by-step instructions – shelf drying
1 Freeze the sample separately, e.g. in a deep-freeze.
NOTE
Ensure that the layer thickness of 1 to 2 cm is not exceeded, since
otherwise the drying time needs to be extended.
2 Check the ice condenser chamber and ensure that it is completely free
from water residues.
3 Close the media drain valve and install the base plate.
4 Switch the unit on 20 to 30 minutes prior to the start of the drying
process in order to let the vacuum pump warm up.
5 Place the plate rack on the base plate.
6 Transport the frozen samples as quickly as possible from the deep-
freeze to the freeze-dryer and place them on the shelves.
NOTE
Recommendation: Store the product vessels on the aluminium shelves or,
if possible, the entire rack with the shelves in the deep- freeze. The
advantage is that due to the higher cold storage capacity of the aluminium
material, the product will remain frozen for a longer period of time so that
the sample will not thaw.
7
nstall the drying chamber. Prior to doing so, check whether the O-ring
is completely free of dirt particles. The ground-in stopper of the acrylic
glass bell must be greased with high-vacuum grease.
8 Ensure that all of the valves of the acrylic glass bell are closed.
9 Ensure that the aeration valve is closed.
10 Ensure that the media drain valve is closed.
11 Start the main drying process either by opening the manual shut-off
valve or by waiting for the electromagnetic valve to open. Vacuum is
applied to the chamber and the freeze-drying process commences.
NOTE
The vacuum pump always runs with maximum power. With this type of
freeze-dryer, the power of the vacuum pump cannot be controlled.
12 The operating panel displays the vacuum, the ice condenser
temperature, and the current operating mode.
13 The end of the process is reached when the ice condenser is no longer
loaded and when it again reaches a final temperature of approximately -
50°C to -54°C. The pressure decreases as a function of the ice
condenser temperature.
14 Switch the vacuum pump off and aerate the drying chamber via the
media drain valve or via a rubber valve.
15 Switch the unit off by actuating the mains power switch and take the
product out of the freeze-dryer.