10 | Operation
Centrifuge GT 4 / 4R
3. Check if the rotor is properly installed by lifting it slightly
on the handle. If the rotor can be pulled up, then it must
be reclamped to the centrifuge spindle.
4. If available close the rotor with the rotor lid.
5. The display is shown.
Entering Parameters
The Fisherbrand GT 4 / 4R Centrifuge offers you a total of 9
acceleration and 10 braking curves with which samples and
gradients can be centrifuged.
After the centrifuge is turned on, the last running profile
selected is shown.
Acceleration Curve
1. Press the key
below the ACC display in order to
open the acceleration profile selection menu.
The display shows the message “Set acceleration”
2. Select the profile by pressing the key
, until the
desired acceleration curve is shown.
Braking Curve
1. Press the
key below the DEC display in order to
open the braking curve selection menu.
The display shows the message “Set deceleration”.
2. Select the profile by pressing the
key, until the
desired braking curve is shown.
Preselecting Speed / RCF
1. Press the
key below the SPEED display in order to
open the speed / RCF value menu.
The display shows the RPM or the RCF value depending
on the display setting. Press the CHANGE key
to
toggle between the two modes.
2. Enter the desired value by pressing the
key
repeatedly, until the desired value shows.
Note:
If an extremely low RCF value has been selected, it will
be corrected automatically if the resulting speed is less than
300 rpm.
Explanation of RCF Value
The relative centrifugal force is given as a multiple of the force
of gravity g. It is a unitless numerical value which is used to
compare the separation or sedimentation capacity of various
devices, since it is independent of the type of device. Only the
centrifuging radius and the speed come into play in it:
r = centrifuging radius in cm
n = Rotational speed in rpm
The maximum RCF value is related to the maximum radius of
the tube opening.
Remember that this value is reduced depending on the tubes
and adapters used.
This can be accounted for in the calculation above if required.
CAUTION:
Do not force the rotor onto the
centrifuge spindle.
If the rotor is very light, then it may be necessary
to press it onto the centrifuge spindle with
pressure.
WARNING:
If the rotor cannot be properly
locked in place after several attempts, then the
Auto-Lock is defective and you are not permitted
to operate the rotor.
Check for any damage to the rotor: Damaged
rotors must not be used.
Keep the centrifuge spindle area of the rotor clear
of objects.
CAUTION:
Check that the rotor is properly
locked on the centrifuge spindle before each use
by pulling it at its handle.
Be sure to check all sealing before starting any
aeorsol-tight applications.
See information in the rotor instruction manual.
RCF
11.18
n
1000
-------------
2
r
=
