Symmetric And Balanced Loading - Beckman Coulter Avanti J Series Instructions For Use Manual

Symmetric and Balanced Loading

To ensure optimal performance and stability, swinging-bucket rotors must be loaded symmetrically.
Two factors affect symmetric loading:
1. The buckets or carriers must be loaded symmetrically with respect to their pivotal axes (the
pivotal axis runs parallel to the crossbar, see
2. The rotor should be loaded symmetrically with respect to its center of rotation.
This means that for best results you should load opposing buckets or carriers with the same type of
labware containing the same amounts of fluid of equal density. Additionally, buckets or carriers
placed opposite each other on the rotor yoke must balance to within a certain weight, typically
10 grams (see the applicable rotor manual for details). Do not exceed the rated maximum load for
buckets or carriers.
NOTE
The JS-4.2A and JS-4.2SMA swinging-bucket rotors incorporate ARIES (Automated Rotor Imbalance
Equilibrating System) "Smart Balance" technology, which provides imbalance compensation for rotors
with buckets that are up to 100 grams unbalanced due to different loading volumes or tube or bag
breakage.
Beckman Coulter supplies buckets and carriers for most rotors in weight-matched sets to make
balancing easier (the weight and date of manufacture are marked on the side of each bucket and
bottom of each carrier). Modular disk adapters are also sold in weight-matched sets. However,
there are variances in weight between sets, as well as variance in weight between previously
purchased adapters. To prevent accidental imbalance, it is important to keep matched sets of
adapters together and to weigh other adapters to be sure they are approximately the same.
Marking matched sets will help you keep them together.
At Rest
Proper Weight Distribution
Improper Weight Distribution
PN JR-IM-10AG
It is not necessary to completely fill all tubes, positions in
adapters, or wells in microtiter plates; however, partially
filled adapters or microtiter plates must be balanced with
At Speed
respect to the pivotal axis of the bucket or carrier as
discussed below.
During a run, buckets and carriers swing 90 degrees from
their at-rest position. The pivotal axis of a bucket or carrier
can be imagined as a line extending across the bucket or
carrier from one pivot pin to the other. If a bucket or carrier
is loaded so that its weight is unequally distributed on
either side of its pivotal axis, it will not hang vertically at
rest and, more importantly, may not swing to a horizontal
position during a run. As a result, extra stress will be placed
on the bucket, carrier, tubes, and/or microtiter plates
during the run, increasing the possibility of breakage or
rotor imbalance.
Using Swinging-Bucket Rotors
Rotor Preparation and Loading
Figure 5.2).
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