Microvolume sample injection

Two position valve application – 4 port diaphragm injector

The internal sample (fixed volume) flowpath is used when very small volumes are required. The sample size is determined by a passage engraved on the valve rotor, allowing precise, repeatable injections.

In Position A, the sample flows through the sample passage while the mobile phase flows through to the column. In Position B, the sample passage is in line with the column and the carrier injects the contents of the sample passage onto the column.

Move your mouse cursor over Position B to "switch" the valve, or go to a non-animated version.

Position A (off)     Position B (on - actuated)

Further reference

More applications with two position valves
Diaphragm injectors and valves