The Modify Needle Position dialog box allows you to specify a change to the default needle position. Two options are available:
Move to location level | The needle stays over the fraction location with the tip of the needle at the specified distance above the location. The distance is specified (in mm) in the adjacent field. Positive or negative values between -10 mm and +10 mm are allowed. |
Use contact control with offset | The needle is lowered into the location to a specified distance above the bottom of the location; the distance is specified (in mm) in the adjacent field. Positive or negative values between -3 mm and +3 mm are allowed. As the location is filled, the needle moves upwards, which prevents the formation of air bubbles below the fraction in small-volume locations, and ensures that the needle is free of drops before it moves to the next fraction position. |
In the case of a fraction collector cluster (FCC), the parameters for different fraction collectors can be specified individually in separate tabs.