Kendro Heraeus Biofuge haemo, Instructions For Use Manual

Page: 39 / 64

Operation
35
RCF value
The r elative c entrifugal f orce (RCF) is usually given in
multiples of the earth gravity g . It is a dimensionless
number 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:
RCF
n
r
= ∗ 



∗
1118
1000
2
.
r = radius of centrifugation in cm
n = speed in rpm
The centrifuge reaches an RCF value
of 16,060 at the maximum speed of
13,000 min
-1
! Check carefully
whether your tubes are designed for
such a strain, and reduce the speed
if necessary.
The maximum RCF value refers to the maximum radius
of the tube.
For the fixed-angle rotor 7500 3325 the above formula
yields for the bottom of the bore (radius 8.5 cm) a
maximum RCF value of 16,060:
RZB
= ∗ 



∗ =
1118
13 000
1000
8 5 16 060
2
.
,
. ,
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.
The figure on the last page of this manual gives a
graphic representation of the relation between speed
and RCF.
Apart from the maximum RCF value RCF
max
(lower
line) this graph also shows the minimum RCF value
RCF
min
, calculated for the meniscus of the sample (up-
per line).