Sampling Sequence - Agilent Technologies 1220 Infinity II LC User Manual

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Injection System Description
Autosampler

Sampling Sequence

The movements of the autosampler components during the sampling sequence
are monitored continuously by the processor. The processor defines specific
time windows and mechanical ranges for each movement. If a specific step of
the sampling sequence can't be completed successfully, an error message is
generated.
Solvent is bypassed from the autosamplers by the injection valve during the
sampling sequence. The sample vial is selected by a gripper arm from a static
sample rack. The gripper arm places the sample vial below the injection
needle. The required volume of sample is drawn into the sample loop by the
metering device. Sample is applied to the column when the injection valve
returns to the mainpass position at the end of the sampling sequence.
The sampling sequence occurs in the following order:
1 The injection valve switches to the bypass position.
2 The plunger of the metering device moves to the initialization position.
3 The gripper arm selects the vial. At the same time, the needle lifts out of the
4 The gripper arm places the vial below the needle.
5 The needle lowers into the vial.
6 The metering device draws the defined sample volume.
7 The needle lifts out of the vial.
8 If the automated needle wash is selected, the gripper arm replaces the
9 The gripper arm checks if the safety flap is in position.
10 The gripper arm replaces the vial. Simultaneously, the needle lowers into
11 The injection valve switches to the mainpass position.
104
seat.
sample vial, positions the wash vial below the needle, lowers the needle into
the vial, then lifts the needle out of the wash vial.
the seat.
1220 Infinity II LC System User Manual