Dionex AS-HV, Operator'S Manual

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AS-HV Operator’s Manual
14
Doc. 065125-01 10/06
2.4.2 AXP Pump
The single-piston AXP pump (P/N 064507) can deliver from 0.01 to
10.00 mL/min of a single solution or eluent. A serial cable connects the
AXP pump to the
AUX
port on the AS-HV side panel (see Section 2.2 ).
The AXP pump is controlled via Chromeleon.
When coupled with the AXP pump, the AS-HV is capable of concentrator
and sample loop loading in the push or pull mode (see
Section 2.3 ). Some
users may prefer to configure the pump as a “pull” device in order to
minimize the contamination that can result when the sample comes into
contact with check valves and seals.
However, Dionex does not recommend using the pull mode for
concentrator loading.
Piston pumps can cavitate and lose prime unless
there is a continuous flow of liquid through the pump. With the AXP
pump, these problems are most likely to occur when performing
concentrator loading in the pull mode.
To ensure optimal performance when doing concentrator loading with the
AXP pump, follow these guidelines:
•
Any Dionex concentrator column (or guard column used as a
concentrator column) may be installed for loading in the push mode.
Select the flow rate recommended for your concentrator column. All
points in the system that will be aspirated should be plumbed with
1.0-mm (0.040-in) ID PEEK tubing (P/N 054410).
When doing sample loop loading with the AXP pump, follow these
guidelines:
•
Pull mode only: The maximum flow rate is 0.75 mL/min. The
backpressure should not exceed 0.07 MPa (10 psi).
NOTE An electronic copy of the AXP/AXP-MS Metering
Pump Operator’s Manual (Document No. 031897) is
provided on the Dionex Reference Library CD-
ROM. Before beginning operation with the pump,
familiarize yourself with the content of the manual.