Whitney Blackmon
Carlos VargasThis Information Applies To: Agilent AA (AA240, AA280) with Graphite Furnace Accessory (GTA)
Issue:
The Programmable Sample Dispenser (PSD) requires the sampling probe to be accurately aligned before the PSD can be used.
The PSD enables the automation of the analysis of samples with the furnace.
When in use, the PSD sits in the front sample compartment of the AA, with the carousel containing the required solutions for analysis.
When the PSD is set up, it is locked into position to maintain alignment. The position of the PSD can be adjusted both in/out or sideways to align the probe arm accurately to the furnace workhead.
The position of the capillary tubing will need to be set up to ensure that:
- The capillary is correctly located in the vials when picking up solution.
- The capillary enters and leaves the GTA without touching the sides of the injection hole in the workhead.
Steps to follow:
1. To set up the probe arm, thread the capillary tubing into the capillary holder following the instructions below. When properly inserted it should appear as shown in Figure 1 and Figure 2.
Figure 1 - Illustration of probe arm showing capillary tubing
To thread the tubing:
- Undo and remove the brown knurled probe guide screw.
- Thread a suitable length of capillary through the threading hole.
- Thread the tubing through the O-rings in the probe guide collar.
- Feed the tubing until it protrudes from the base of the probe guide collar
- Tighten the knurled probe guide screw
Figure 2- Photo of capillary tubing in place.
2. The capillary holder is then adjusted so that the capillary is central to, and not touching, the bottom of the vial. The probe arm should be central in the injection hole in the workhead when the probe arm moves to this position, see Figure 3 and Figure 4. For adjustment, use the adjustment knobs located under the carousel, see Figure 5).
Figure 3 - Video showing correct adjustment of the capillary holder.
Figure 4 - Probe positioning in a sample vial
Figure 5 - PSD showing adjustment and locking knobs
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Tips: Avoid misalignment by always performing adjustments with a straight capillary
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The PSD is now aligned.
