Instruction manual for CoolSafe
01012016QA01
Item No. 700637
CopyRight © 2016
Page
9
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30
A hose may be attached to the nozzle to minimize spillage. Remember to close the drain valve after
use.
4.2.6
Pressure regulation valve (optional)
The pressure regulation valve is placed on the front of the cabinet. It is a needle valve that is used
for fine-tuning the flow of air or inert gas into the ice condenser. It is used to reduce the hysteresis
on the pressure regulation.
Never close a needle valve too hard
– there is a risk of the needle welding to the valve seat due to
the very tight fit.
4.2.6.1 Using the pressure regulation
The pressure regulation works from the display of the controller. Here a set point of the pressure
during the freeze drying is defined.
If a set point of e.g. 1 hPa is entered, the controller will try to maintain the pressure of 1 hPa during
the freeze drying process.
So when the vacuum valve is open and the vacuum pump reduce the pressure to 1 hPa, then the
pressure regulation valve will open, in order to inject air or inert gas to the freeze dryer chamber.
However, when the regulation valve open, then the pressure will increase very fast and with no
control. To enable a controlled pressure increase, a needle valve is built in, enabling fine tuning of
the flow into the chamber.
This will prevent an over-shoot in the chamber pressure, and enabling the control of the pressure
during the process.
In order to get the best result of the pressure regulation and the needle valve, it is necessary to make
a fine tuning of the needle valve. Same applies in case the set point pressure is changed.
So whenever the set point is changed, the needle valve must be fine-tuned.
If the needle valve is closed too much, then the pressure will still decrease, in which case the needle
valve must be opened more, or if the pressure increases too fast, the needle valve must be closed
more.
4.3
Interface, data acquisition and control
On the back of the CoolSafe cabinet, to the right of the name plate, slot for a SD card and a mini
USB connection is placed.
During freeze drying all time, pressure and temperature data is stored on the SD card at one minute
intervals. The data saved on the SD card is formatted for use in the LaboGene freeze drying software
package. From the software the data can be formatted and saved in an Excel compatible format.
The software package is included in the delivery.
Under the SD card slot a mini USB connection is available. This is used for connecting a computer,
running the LaboGene freeze drying software, from which the freeze dryer can be controlled. The
software offers a graphical user interface showing the complete freeze dryer system and the status
