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19
Intended use
Note:
Make sure there is no pressure when switching
between the columns so that the columns are not
damaged.
Fig. 18
Alternating sample precleaning – precolumn B is purged
and precolumn A is filled with sample
After switching over the valve, precolumn B is cleaned in oppo-
site direction for the next analysis. The sample from precolumn
A is flushed in opposite direction with the first solvent into the
analytical column.
Switchover of the
direction of flow
Pump B
Eluent B
Pump A
Eluent A
Waste
Detector B
Detector A
Precolumn B
Precolumn A
Column
Injection