Dionex UltiMate 3000 Series, Руководство по эксплуатации

Страница: 197 / 236

UltiMate 3000 Series:
SD, RS, and BM Pumps
Operating Instructions Page 183
9 Optimizing the Pump for Specific Applications
All pump types except ISO-3100SD and BM pumps
In the standard configuration, the pump has been optimized for the gradient delay volume and
ripple.
The gradient delay volume of an HPLC system is defined as the volume that the pump must
deliver until a change in solvent composition reaches the head of the column. Reducing the
gradient delay volume allows changes in the solvent composition to become effective on the
column much earlier, thus having a faster effect on the elution of analytes. For information
about the gradient delay volume of the different pump types, see the Technical Information
section (

page 187).
For gradient separations at low flow rates (for example, less than 100 µL/min) or very steep
gradients, you can adapt the gradient delay volume to your requirements by replacing the two-
step mixing system with which the pump is shipped with either a two-step mixing system with
lower volume or the single-step mixing system. In both cases, the ripple will increase.
In addition, two-step mixing systems with a higher volume are available for the pump.
Operating the pump with these mixing systems will reduce the ripple but increase the gradient
delay volume.
For more information about the two-step mixing systems, see the next page. For information
about the single-step mixing system, see page 185.