Centrifugation With Preselected Time; Continuous Operation; Short-Time Centrifugation; Display Of The Relative Centrifugal Force (Rcf) - Hettich ROTOFIX 32 A Bedienungsanleitung

15.1

Centrifugation with preselected time

•
Set the desired speed with the keys
•
Set the desired time with the keys
•
Press the key . The rotation indicator
START
The time is displayed in minutes. The last minute is counted down in seconds.
When the time is displayed in minutes, a point flashes next to the number.
•
After expiry of the time or if the centrifugation run is interrupted by pressing the key
with the set brake step.
During the centrifugation run, the rotor speed or the resulting RCF value and the remaining time are displayed.
15.2

Continuous operation

•
Set the desired speed with the keys
•
Set the time to zero with the key
•
Press the key . The rotation indicator
START
The first minute is counted up in seconds, and then the time is displayed in minutes.
When the time is displayed in minutes, a point flashes next to the number.
•
Press the key to end the centrifugation run. The rotor runs down with the set brake step.
STOP
During the centrifugation run, the rotor speed or the resulting RCF value and the expired time are displayed.
15.3

Short-time centrifugation

•
Set the desired speed with the keys
•
Keep the key pressed. The rotation indicator
IMPULS
from 0.
The first minute is counted up in seconds, and then the time is displayed in minutes.
When the time is displayed in minutes, a point flashes next to the number.
•
Release the key
IMPULS
During the centrifugation run, the rotor speed and the expired time are displayed.
15.4

Display of the relative centrifugal force (RCF)

The relative centrifugal force (RCF) can be displayed during the centrifugation run.
If the relative centrifugal force (RCF) is used, the centrifuging radius must be entered.
•
Keep the key pressed during the centrifugation run.
RCF
The relative centrifugal force (RCF) appears in the speed indicator (RCF = displayed value x 100).
•
Release the key again. The speed is displayed.
RCF
16

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:
RCF
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.
The relative centrifugal force (RCF) stands in relation to the revolutions per minute and the centrifugal
radius.
beneath the speed indicator.
beneath the time indicator.
appears while the rotor is turning.
beneath the speed indicator.
beneath the time indicator. "--" is displayed.
appears while the rotor is turning. The time count starts from 0.
beneath the speed indicator.
again to end the centrifugation run. The rotor runs down with the set brake step.
2
⎛ ⎞
RPM
⎜ ⎟
= × ×
r 1,118
⎝ ⎠
1000
For more on the centrifugal radius see the chapter " Anhang/Appendix,
Rotoren und Zubehör/Rotors and accessories".
appears while the rotor is turning. The time count starts
RCF
⇒ =
RPM
×
r 1,118
EN
, the rotor runs down
STOP
×
1000
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