The fraction collectors hold either one or two racks. Racks ensure that the collection vessels are positioned correctly under the drop former.
To install a rack:
Select the rack and insert the collection tubes.
Ensure that the tops of the collection tubes are even. Tubes that do not drop fully into the rack might obstruct arm movement.
Grasp the rack so that tube 1 is positioned at the front left corner.
Align the holes on the left side of the rack with the corresponding guide pins in the drip tray and gently press downward. When correctly installed, both sides of the rack will sit on the ridges in the drip tray. The test tube numbers on the rack will appear upright when viewed from the front of the fraction collector.