Genevac HT-24, Руководство пользователя

Страница: 39 / 60

User Manual Genevac HT-24
10-1562 Issue 3-7 March 2014
37
Balancing the rotor
Always make sure that swings of the same static weight are placed opposite each other on
the rotor.
Caution: Opposing swings must be identical (the same type and version) ideally
the same version of swing should be used in all four positions of each rotor level.
An imbalance detection system will stop the rotor safely if the imbalance is unacceptably
high. However, to minimise wear-and-tear, always balance opposing sample holders within
10 g.
It is preferable to run the evaporator with all four swings fitted to each rotor level, if the rotor
is to be only partially loaded, fill the top level first, then the second, then the third. If there
are only enough samples to fill two swings, it is best to redistribute the samples into four
holders to help distribute the heat flow evenly between samples and to reduce mechanical
stress on the rotor.
Alternatively, two empty swings can be placed on the unused rotor positions; or better still,
loads may be counter-balanced using
dummy samples of a similar solvent composition. For
example, do not balance water / acetonitrile with water, as partway through the run the
acetonitrile evaporates but the water remains, resulting in a significant imbalance.
Note that with
Fast-Stack
TM
swings, balancing becomes more complex. Suppose 96 well
microtitre plates are loaded onto FastStack swings. In one swing, the lower microtitre plate
is empty, the upper microtitre plate is filled to 1.8 ml per well. On the opposing swing, the
reverse is true. The two swings weigh the same but would imbalance the rotor as their
centres of mass will be at a different radius when the swings rotate to their operating attitude.
Swings are the same weight but not balanced