EN
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16 Acoustic
Signal
The acoustic signal sounds:
•
Upon the appearance of a disturbance in 2 second intervals.
•
After completion of a centrifugation run and rotor standstill in 30 second intervals.
The acoustic signal is stopped by opening the lid or pressing any key.
The signal after completion of the centrifugation run can be activated or deactivated in the following manner, if the
rotor is at standstill:
•
Hold down the key
for 8 seconds.
After 8 seconds,
SOUND / BELL
appears in the display.
•
Set
OFF
or
ON
with the key or .
•
Press the key
START
in order to store the setting.
As confirmation,
∗∗∗
ok
∗∗∗
will be displayed for a short period.
17 Recall hours of operation
Recall hours of operation is only possible during rotor standstill.
•
Hold down the key
for 8 seconds.
After 8 seconds,
SOUND / BELL
appears in the display.
•
Press the key
once again.
The centrifuge’s hours of operation (
CONTROL:
) are displayed.
•
Press the key or to exit the hours of operation recall.
18 Relative centrifugal force (RCF)
The relative centrifugal force (RCF) is given as a multiple of the acceleration of gravity (g). It is a unit-free value and
serves to compare the separation and sedimentation performance.
These values are calculated using the formula below:
1,118
r
2
1000
RPM
RCF
×
×
=
⇒
1000
1,118
r
RCF
RPM
×
×
=
RCF = relative centrifugal force
RPM = rotational speed (revolutions per minute)
r = centrifugal radius in mm = distance from the centre of the turning axis to the bottom of the centrifuge.
For more on the centrifugal radius see the chapter ” Anhang/Appendix,
Rotoren und Zubehör/Rotors and accessories”.
The relative centrifugal force (RCF) stands in relation to the revolutions per minute and the centrifugal
radius.
19 Centrifugation of materials with higher density
The rotors are designed to centrifuge substances up to a maximum mean homogenous density of 1.2 kg/dm
3
when
rotating at the stated speed.
Denser substances must be centrifuged at lower speed.
The permissible speed can be calculated using the following formula:
speed
Rated
x
density
Greater
1.2
=
)
(n
speed
Reduced
red
e.g.: RPM 4000, density 1.6 kg/dm
3
RPM
3464
=
4000
x
1.6
1.2
=
n
red
If in doubt you should obtain clarification from the manufacturer.
