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2-16KC
Using the Centrifuge
Version 03/2010, Rev. 1.7 of 27/01/2012
33
Translation of the original operating manual
Density
If the density of the liquid is higher than 1.2 g/cm
3
, the value must be
adapted manually. This, in turn, reduces the maximum final speed
(see 11.4.2 “Density“). A downward facing arrow ( ) will be displayed
in the speed field. Values between 1.2 and 9.9 g/cm
3
are possible.
Standstill Cooling
Depending on the substances to be centrifuged, it may make sense
to precool the centrifuge. The precooling prevents the cooled samples
in the uncooled centrifuge from heating up to an inadmissible
temperature.
If the standstill cooling is activated, the centrifuge starts to precool
after it is switched on. The lid must be closed.
Unmoved air in the rotor chamber distorts the measuring and control
behavior and causes the compressor to freeze overs. At
temperatures below 0°C, aqueous liquids will freeze, making
sedimentation impossible.
Ensure that the rotor temperature will not fall below 0 °C if it is at
a standstill!
Rapid cooling program "RAPID TEMP"
Precooling at a standstill may distort the measurement results and
subsequently cause increased wear of the mechanical components.
This is why the centrifuge has a special program that precools the
centrifuge rapidly under defined conditions:
Select the option “Progr” in the “Standard” menu and confirm the
selection. The program list will be displayed.
Select the program "RAPID TEMP" on the program list and
confirm the selection. The display shows 1/3 of the maximum
rotor speed and the corresponding RCF value. The deceleration
(brake) and acceleration curves correspond to curve 9 and the
runtime field indicates “infinite” (continuous run).
The program will only be loaded if the actual temperature is above
the set temperature.
The program runs until the set value is reached. Then, a sound signal
is issued, and the standstill cooling is activated. The program that
was set beforehand will be reloaded.
Press the stop key to determinate the rapid cooling program
prematurely.
The automatic lid opening function is suppressed after a rapid
cooling phase in order to prevent the system from reheating.