Agilent Technologies G1313A, Reference Manual

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Introduction to the Autosampler
Introduction to the Autosampler
Introduction to the Autosampler
Five models of Agilent 1100 Series autosamplers are available; within this
introduction they will be referred to as the standard, the micro, the
preparative autosamplers and the thermostatted autosamplers. Unless
otherwise stated all information in this section is valid for all models.
The Agilent 1100 Series autosamplers and Agilent 1100 Series
thermostatted autosamplers are designed for use with other modules of
the Agilent 1100 Series LC system, with the HP 1050 Series, or with other
LC systems if adequate remote control inputs and outputs are available.
The autosamplerss are controlled from the Agilent 1100 Series control
module or from the Agilent ChemStation for LC.
Three sample-rack sizes are available for the autosamplers. The standard
full-size rack holds 100 × 1.8 ml vials, while the two half-size racks provide
space for 40 × 1.8 ml vials and 15 × 6 ml vials respectively. Any two
half-size racks trays can be installed in the autosamplers simultaneously.
A specially designed sample-rack holding 100 × 1.8 ml vials is available for
use with the thermostatted autosamplers. The half-size racks trays are not
designed for an optimal heat transfer when they are used with a
thermostatted autosampler.
The autosamplers transport mechanism uses an X-Z-Theta movement to
optimize vial pick-up and return. Vials are picked up by the gripper arm,
and positioned below the sampling unit. The gripper transport mechanism
and sampling unit are driven by motors. Movement is monitored by optical
sensors and optical encoders to ensure correct operation. The metering
device is always flushed after injection to ensure minimum carry-over.
The standard analytical head device provides injection volumes from
0.1 – 100 µl. The micro analytical head device provides injection volumes
from 0.1 – 40 µl. Two preparative head devices provide injection volumes
from 0.1 – 900 µl. One head is limited by a system pressure of 200 bars, the
other by a system pressure of 400 bars.
The six-port (only 5 ports are used) injection valve unit is driven by a
high-speed hybrid stepper motor. During the sampling sequence, the valve
unit bypasses the autosamplers, and connects flow from the pump to the
column directly. During injection and analysis, the valve unit directs the
flow through the autosamplers which ensures that all of the sample is
injected onto the column, and that the metering unit and needle are always