Chromatography Forum

Hello,

I have been working on an older set-up using a Dionex AS-40 autosampler. The autosampler, itself is a work horse. I haven't had any trouble with it after I figured out the correct programming but have only had success injecting samples from 5.0 mL vials. If it try to inject from a 0.5 mL vials, the autosampler recognizes the 0.5 mL vial but results from standards are spotty at best. I do not get enough data to try and figure out what the issue may be.

Is there a programming change that I need to make to to adjust to the smaller volume injection? Or would there be a modification to the instrument that I would need to make, such as a tubing length change?

Thanks in advance for any input.

Hi lewright,

You may need to adjust the timing of the relay signal sent to the sampler by the IC. For 5 mL vials, the relay is usually closed at -2.3 min before the IC valve actuates. For 0.5 mL vials, the relay is usually closed at -1.0 min before the IC valve actuates.

Hi John,

Thank-you so much for the reply. I will give that a try.