ROTORS AND ACCESSORIES
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4.3 Loading The Rotor
The rotors must carry a full complement of cups/buckets and/or trunnion rings, but
all cups/buckets need not be loaded. Loads must be placed symmetrically about
the rotor and opposing loads should balance to within 2 grams. Where possible,
balancing by sight is usually sufficient.
Before loading centrifuge tubes ensure that the appropriate colour coded-adapter
or rubber cushion is correctly positioned in the cup/bucket. Check that all tubes
project equally from the upper surface of the rotor.
Finally, if using a swing-out rotor, check that all cups of trunnion rings swing freely.
If necessary, apply a light smear of petroleum jelly to the rotor pivot slots.
Failure to load the rotor correctly can result in serious imbalance and possible
damage to the centrifuge.
Biologically hazardous material should only be centrifuged in sealed
buckets or cups.
4.4 Rotor Speed
Maximum Speeds of rotors (See section 4.5) are calculated on the basis of tubes
filled with a sample of specific gravity 1.2. If liquids of higher specific gravity are
used, the maximum speed of the rotor must be reduced according to the formula:
Where M = New maximum speed
N = Maximum rotor speed at 1.2 specific gravity
S = Specific gravity of sample used
