Dionex AS-HV, Operator'S Manual

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2 • Description
Doc. 065125-01 10/06
7
Sampling Needle
The sampling needle is used to aspirate sample from sample containers.
The AS-HV is shipped with a PEEK Sampling Needle Kit (P/N 064511). The kit
includes the sampling needle (a piece of specially pre-bent 0.8-mm (0.030-in) ID
PEEK tubing), fittings, and mounting hardware.
The PEEK tubing is not only the sampling needle, but the point at which the
sample is introduced to the IC. This transfer mechanism minimizes contamination
that can be caused by fittings, extra tubing, and manual sample handling.
Optional: A Sampling Needle Kit–PTFE Lined and Sleeved (P/N 064056)
containing a stainless steel needle that is lined and sleeved with PTFE
(polytetrafluoroethylene).
Sampling Needle Guide
The AS-HV is shipped with a sampling needle guide (P/N 064519). The guide
serves two purposes:
•
To ensure that the PEEK sampling needle does not bend or flex as it pierces
the septum in the sample container cap.
•
To ensure that the sample container is not lifted out of the sample rack during
sampling.
Rinse Station
The rinse station cleans the sampling needle between samples. During the
cleaning cycle, the needle is inserted into the rinse fluid, fluid is drawn and then
dispensed through the needle, and the dispensed fluid is directed to waste. The
rinse station consists of:
•
A 150 mm reservoir of rinse fluid. Dionex recommends using ASTM Type I
(or better) filtered, deionized water as the rinse fluid.
•
A variable-speed peristaltic pump that provides a supply of fresh rinse fluid to
the reservoir. The potentiometer knob fitted above the pump is used to adjust
the flow rate (see
Section 3.2.3 ).
If an external rinse source is available, the reservoir can be connected directly to
this source and the peristaltic pump can be replumbed for operation as the sample
loading pump. For more information, refer to
Section 2.4.4 .