Pump and Flow Control
Splitting the Flow (Program Example)

The Dionex Active Flow Splitter (MRA), which is usually part of an APS system for Autopurification, splits the HPLC flow and directs the smaller portion to a Mass Spectrometer. The following program is a typical example of how to set up flow splitting in a PGM File:

 . . .

 3DFIELD.Step =  0.5 [s]

 Pump.Flow = 50.000 [ml/min]

; MRA settings: Communicate the used flow rate and the target

; value for the split ratio

; Caution: You might find it useful to add an implicit

; assignment, such as MRA.Flow = Pump.Flow. However, this is

; not possible as most pumps do not deliver the target value

; immediately. The Flow property always sets the actual flow.

; Therefore, you have to set the MRA flow explicitly:

 MRA.Flow = 50.000 [ml/min]

 MRA.SplitRatio = 20000

0.000 Autozero 

 Wait Ready

 Inject

 UV_VIS_1.AcqOn

; To minimize wear, start the MRA after the injection if possible:

 MRA.RunState = On

 . . .

; You can change the split ratio during a run.

1.300 MRA.SplitRatio = 100000 

 . . .

2.600 MRA.SplitRatio = 20000

 . . .

10.000 UV_VIS_1.AcqOff 

; To minimize wear, stop the MRA after a run if possible

 MRA.RunState = Off

 End