Collecting Fractions
Program Example (Two Detection Channels)

 Tip:

If the Fraction license is installed, Chromeleon supports two detection channels. You need the Extended Fraction Collection license if you want to use more than two detection channels.

A Program for a timebase including a Fraction Collector and two detection channels might look as follows:

-0.300 Flow = 20.000

 %B = 10

 UV_VIS_1.Step = 0.50

 UV_VIS_1.Average =  On

 UV_VIS_1.MaxAutoStep = 1.0

 Pressure.LowerLimit = 10.00

 Pressure.UpperLimit = 200.00

;********************************************************************

;*Definition of triggers for fraction collection starts here

;********************************************************************

;Definition copied from template <Timebase>\FractionCollectionTemplate!

;FracStart: Start of fraction collection

 Trigger FracStart  FracStartDetected

 Collect

 Log SFM_A.Tray

 EndTrigger

;TubeChange: The fraction is collected to another tube when the current tube is full

 Trigger TubeChange FracTubeChange

 Drain

 SFM_A.TubePosition = FractionCollection.TubePosition

 Collect

 EndTrigger

;FracEnd: End of fraction collection

 Trigger FracEnd FracEndDetected

 MovementMode = InterruptAndEject

 Drain

 SFM_A.TubePosition = FractionCollection.TubePosition

 EndTrigger

;********************************************************************

;*Definition of triggers for fraction collection ends here

;********************************************************************

; Maximum liquid level in a tube in ml:

 PumpDevice = "Pump"

 TubeMaxVolume = 10

; Maximum number of installed tubes:

 FractionCollection.TotalNumberInstalled = 1092

; Basic fraction collection parameters:

 MaxTubesPerFraction =  Unlimited

 TubeWrapping = No

 TubeChangeDuration =  2.0 [s]

 ChannelEvaluation =  All

; Delay time between detector output and switching valve or tube:

 DelayTime = 0.8

 DetectionChannel2.OffsetTime = 0.0

 DetectionChannel3.OffsetTime = 0.0

; Conditions for online peak recognition at program start:

 DetectionChannel2.Name = "UV_VIS_1"
 ;Slope at peak start:

 DetectionChannel2.PeakStartSlope = 2.000
 ;Minimum signal height at peak start:

 DetectionChannel2.PeakStartThreshold = 10.00
 ;Slope after peak maximum:

 DetectionChannel2.PeakMaxSlope = -4.000
 ;Slope at peak end:

 DetectionChannel2.PeakEndSlope = -4.000
 ;Maximum signal height at peak end:

 DetectionChannel2.PeakEndThreshold = 5.00
 ;Signal must be less than this threshold value

 ;before a new peak start can be recognized

 DetectionChannel2.ThresholdNoPeakEnd = 200
 ;Baseline drift correction:

 DetectionChannel2.BaselineOffset = 0.000

 DetectionChannel2.BaselineDrift = 0.000

; Conditions for online peak recognition for the 2. detection channel:

 DetectionChannel3.Name = "UV_VIS_2"
 DetectionChannel3.PeakStartSlope = 2.000
 DetectionChannel3.PeakStartThreshold = 10.00
 DetectionChannel3.PeakMaxSlope = -5.000
 DetectionChannel3.PeakEndSlope = -4.000
 DetectionChannel3.PeakEndThreshold = 5.00
 DetectionChannel3.ThresholdNoPeakEnd = 200
 DetectionChannel3.BaselineOffset = 0.000

 DetectionChannel3.BaselineDrift = 0.000

; Separation start with injection:

-0.100 UV.Autozero

0.000  Wait Ready

 Flow = 20.000

 %B = 10

 Sampler.Inject

 UV_VIS_1.AcqOn

; Basic fraction collection parameters:

 CollectFractions =  By_Peak

; Gradient Program:

 Flow = 20.000

 %B = 10.0

10.000 %B = 90

13.000 %B = 90

13.000 UV_VIS_1.AcqOff

 CollectFractions =  No

; Regeneration and equilibration phase of the gradient program:

15.000 Flow = 20.000

 %B = 90

16.000 %B = 10

 End

 Notes:

The trigger block used in this program example refers to a preparative application with a Dionex Sample and Fraction Manager (SFM). Besides, the trigger block is intended for a preparative pump.

In the example, DetectionChannel1 has not been used as the first detection channel because '1' and 'I' look almost identical when Courier is the selected font.

For more program examples, refer to:

 Program Example (One Detection Channel)

 Fraction Collection Control via an MS

 Fraction Collection Control via an MS for Different Samples

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