Fisher Scientific AccuSpin Micro 17, Instructions For Use Manual

Page: 33 / 79

Operation
29
Entering the RCF value
You can adjust the RCF pre-selected value in steps of
100 xg. The setting of pre-selected value is entered
analogously to the speed.
The RCF value can be set to a minimum of 100xg. The
setting of a maximum RCF depends on the type of
centrifuge.
The displayed RCF value is always corre-
sponding to the maximume of centrifuge
radius of the micro liter rotor 24 x 2ml (7500
3424).
For other rotors please use the formula beneath or
follow the enclosed speed/RCF diagrams.
Mind the rounding difference!
Due to limited display digits there is a need
to round the values. The direct comparison
between the two values speed and RCF is
therefore restricted.
Concerning the RCF value
The r elative c entrifugal f orce (RCF) is given in multi-
ples of the earth gravity g . It is a dimensionless number
value that allows one to compare the efficiency of
separation or sedimentation of diverse instruments,
since it is independent of the instrument used. The only
values entered in the equation are radius and speed of
centrifugation:
r
n
RCF
∗
⎟
⎠
⎞
⎜
⎝
⎛
∗ =
2
1000
18 . 11
r = radius of centrifugation in cm
n = speed in rpm
The maximum RCF value refers to the maximum ra-
dius of the vessel bore.
Please note that this value becomes lower
depending on the tubes and adapters used.
You may take this into account when calculating the
RCF value for your application.