Technical data

To control the shelf temperature, one shelf with a measuring
sensor has to be connected. The plug of the shelf with the
measuring sensor has to be connected to the socket of the
vacuum-tight electrical leadthrough.
All shelves are supplied with the same heating power. It is not
possible to consider different heat requirements of the upper and
lower shelves. Thus, slight differences in temperature between the
shelves cannot be avoided.
When freezing and drying is performed separately outside the ice
condenser chamber, the system starts directly with the main drying
phase. In case the unit is equipped with a pressure control valve,
the vacuum pump is activated and warmed up.
As soon as the shelves with the pre-frozen samples have been put
into the unit, the unit and the drying chamber are sealed.
The main drying process has to be activated in the control system
so that the pressure control valve opens and the main drying
phase starts.
When the pressure falls below the pre-selected „Heater safety
pressure“, the heater of the shelves is activated. The heater
remains on until the nominal value of the shelf is reached.
Temperature controlled shelf with build-in
measuring sensor PT100
(4-pole precision connector)
Temperature-controlled shelf
without built-in measuring
sensor PT100
(“banana plug”)
Intermediate valve or fan
(6-pole precision connector
Shelf 2 (middle, yellow)
Operating Manual Freeze Dryer ALPHA 1-4 LSC / ALPHA 2-4 LSC Description of the Freeze Drying Processes • 21