11
Introduction to the Autosampler
1
Sampling Sequence
Injection Sequence
Before the start of the injection sequence, and during an analysis, the injection
valve is in the mainpass position (Figure 2 on page 11). In this position, the
mobile phase flows through the autosamplers metering device, sample loop,
and needle, ensuring all parts in contact with sample are flushed during the
run, thus minimizing carry-over.
Figure 2 Mainpass Position
When the sample sequence begins, the valve unit switches to the bypass
position (Figure 3 on page 11). Solvent from the pump enters the valve unit at
port 1, and flows directly to the column through port 6.
Figure 3 Bypass Position