Rotor Maintenance; Removing And Installing The Angle Rotor; Loading The Rotor; Overloading Rotors - Labnet Prism Instruction Manual

4 | LABNET PRISM MICROCENTRIFUGE

6.2 Rotor Maintenance

The rotor should be cleaned thoroughly after each use. Thorough cleaning must be performed when
spinning samples containing phenol or phenol chloroform. Periodically inspect the rotor for dents,
dings, scratches, discoloration and cracks. If any damage to the rotor is found, discontinue use of the
rotor immediately and replace.

6.3 Removing and Installing the Angle Rotor

The Prism™ Microcentrifuge comes complete with a standard 24-place rotor installed. To remove
the rotor for cleaning, remove the rotor securing screw from the motor shaft by turning the screw
counterclockwise, using the rotor wrench. Lift the rotor directly upward in a straight vertical motion.
To replace rotor, first make sure the motor shaft and rotor mounting hole are clean. Place the rotor on
the motor shaft. Reinstall the rotor securing screw on the motor shaft by turning it clockwise. Hold the
rotor with one hand and tighten the rotor securing screw, using the rotor wrench.

6.4 Loading the Rotor

Tubes to be loaded should be filled equally by eye. The difference in the weight between the tubes
should not exceed 0.1 gram. Tubes should always be loaded so that there is equal spacing between all
tubes. One or two additional loaded tubes may need to be added to achieve this. Refer to Figure 1. to see
one typical balancing scheme.

6.5 Overloading Rotors

The maximum load of the rotor and maximum speed has been established by the manufacturer. Do
not attempt to exceed these values. The maximum speed of the rotor has been established for liquids
having a homogeneous density of 1.2g/ml or less. In order to centrifuge liquids with a higher density
it is necessary to reduce the speed. Failure to reduce the speed may result in damage to the rotor and
centrifuge. The revised maximum speed can be calculated with the following formula:
Reduced speed (n ) =
higher density value
red
Reduced speed (n ) =
higher density value
Example: Where the density of the liquid is 1.7, the new maximum speed would be calculated as follows:
red
1.2
(n ) = × 15,000 = 12,602 rpm
1.7
red
1.2
(n ) = × 15,000 = 12,602 rpm
1.7
red
If in doubt concerning maximum speeds, please contact the manufacturer for assistance.
Figure 1. Loading the rotor to achieve balance
1.2
× max speed (n
1.2
× max speed (n
)
max
)
max