Defining the Reactions to Certain Events

Collecting Fractions
Defining the Reactions to Certain Events

A peak start, peak maximum, and peak end are recognized if certain conditions are fulfilled (see Recognizing Peak Start, Peak Maximum, and Peak End).

If one of these events occurs, Chromeleon issues certain commands to the Fraction Collector. These commands can be defined in the Program. In the respective Trigger block, you can define device-specific actions for your Sample and Fraction Manager or fraction collector.

Event	Condition	Action
FracStartDetected	A peak start, which means the start of a new fraction, "arrives" at the switching valve/ tube. Note: If, during a peak, a peak start is detected on another channel, a new fraction is also started for ChannelEvaluation = Any.	Switch to next fraction.* Switch to collect.
FracTubeChange	The tube is filled to the limit.	Switch to next tube.
FracEndDetected	A peak end, which means the end of a fraction, "arrives" at the switching valve/ tube.	Switch to waste. Switch to next fraction.*

* Switching to the next fraction is needed only once. It depends on the type of hardware whether this is better to switch to the first tube of the next fraction at the peak start or at the peak end.

For an overview of the fraction collection topics, refer to Collecting Fractions.