Valve (G1316A/B/C)

The Valve section allows you to switch the solvent flow between the column and the bypass or a second column for column switching or to reverse the solvent flow for backflushing.

Column Selection
In trace analysis small amounts of compound must be analyzed in the presence of a large amount of interfering matrix. A chromatogram can be improved by using a multiple column technique. The entire sample can be eluted from a short column to obtain a rough separation and only the fraction that contains the relevant peaks can be passed on to a longer column to do the separation. The first column is called a clean-up column or pre-column and the second column is called the analytical column.
In column switching, a relatively large volume of sample is injected onto a short analytical column. The early eluting trace component of interest passes into a second longer analytical column which has the resolving power to separate the trace component from any early eluting interferences. These components are held at the top of the second column and the column switching valve is switched to divert later components eluting from the first column directly to the detector. After passage of these compounds through the detector, the flow is again diverted through the second column and the trace components can be analyzed.
Backflushing
Column backflushing is used to remove strongly held components from the top of a column after the components of interest have been analyzed. The sample is injected at the top of the column and after elution of the solute of interest the switching valves are used to reverse the eluent flow so the eluent flows into the bottom of the column and out of the top to the waste. By doing this strongly held components are quickly removed from the top of the column.

2-Position 6-Port Valve

Port 1 → 6	connected ports: 1 with 6, 2 with 3, 4 with 5
Port 1 → 2	connected ports: 1 with 2, 3 with 4, 5 with 6
Use current	the valve remains in the current position at the end of a run
Next pos. after run	the valve switches to the next position at the end of a run

2-Position 8-Port Valve (G1316C only)

Port 1 → 3	connected ports: 1 with 3, 2 with 8, 4 with 6, 5 with 7
Port 1 → 7	connected ports: 1 with 7, 2 with 4, 3 with 5, 6 with 6
Use current	the valve remains in the current position at the end of a run
Next pos. after run	the valve switches to the next position at the end of a run

2-Position 10-Port Valve

Port 1 → 10	connected ports: 1 with 10, 2 with 3, 4 with 5, 6 with 7, 8 with 9
Port 1 → 2	connected ports: 1 with 2, 3 with 4, 5 with 6, 7 with 8, 9 with 10
Use current	the valve remains in the current position at the end of a run
Next pos. after run	the valve switches to the next position at the end of a run

4-Position 10-Port Valve (G1316C only)

Position 1	Inlet port 1 to Outlet port 1'
Position 2	Inlet port 2 to Outlet port 2'
Position 3	Inlet port 3 to Outlet port 3'
Position 4	Inlet port 4 to Outlet port 4'
Use current	the valve remains in the current position at the end of a run
Next pos. after run	the valve switches to the next position at the end of a run

6-Position/14-Port valve (G1316C only)

Pos 1, Pos 2, .. Pos 6	Positions 1 to 6, a separate entry for each position
Use current	the valve remains in the current position at the end of a run
Next pos. after run	the valve switches to the next position at the end of a run

8-Position 9-Port Valve (G1316C only)

Pos 1, Pos 2, .. Pos 8	Positions 1 to 8, a separate entry for each position
Use current	the valve remains in the current position at the end of a run
Next pos. after run	the valve switches to the next position at the end of a run

12-Position 13-Port Valve (G1316C only)

Port c → n	center port (c) to pert n (n = 1 to 12)
Use current	the valve remains in the current position at the end of a run
Next pos. after run	the valve switches to the next position at the end of a run

Generic Valve

Pos 1, Pos 2, .. Pos n	Positions 1 to 6, a separate entry for each position up to the number of configured positions
Use current
Next pos. after run	the valve switches to the next position at the end of a run

For the mode selected, the diagram shows how you need to connect your capillaries and columns (except the Generic Valve type). The heavy lines on the diagram indicate the solvent flow path.If a column switching valve is not installed, the Column Switching Valve section is disabled.