Variable Stroke Volume - Agilent Technologies 1220 Infinity II LC User Manual

Variable Stroke Volume

Due to the compression of the pump-chamber volume, each plunger stroke of
the pump generates a small pressure pulsation, influencing the flow ripple of
the pump. The amplitude of the pressure pulsation is dependent mainly on the
stroke volume and the compressibility compensation for the solvent in use.
Small stroke volumes generate pressure pulsations of smaller amplitude than
larger stroke volumes at the same flow rate. In addition, the frequency of the
pressure pulsations are higher. This decreases the influence of flow pulsations
on quantitative results.
In gradient mode, smaller stroke volumes result in less flow ripple and
improve composition ripple.
The pump uses a processor-controlled spindle system to drive its plungers.
The normal stroke volume is optimized for the selected flow rate. Low flow
rates use a small stroke volume, while higher flow rates use a larger stroke
volume.
When the stroke volume for the pump is set to AUTO mode, the stroke is
optimized for the flow rate in use. A change to larger stroke volumes is
possible but not recommended.
1220 Infinity II LC System User Manual
Solvent Delivery System Description

Variable Stroke Volume

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