Binary Pump Solvent Compressibility Calibration - Agilent Technologies 1260 Infinity II User Manual

Binary Pump Solvent Compressibility Calibration

Description
Each solvent or solvent mixture has unique compressibility at different
pressures. In order to deliver accurate flow with minimal pressure- and
composition ripple over the full operational pressure range, it is necessary
that the pump compensates precisely for the compressibility of the solvents in
use.
The binary pump comes with compressibility parameters for the most
common HPLC solvents and solvent mixtures. If a solvent is not available in
the list of pre-calibrated solvents, the solvent compressibility calibration
allows the appropriate compressibility data to be generated.
Technical background
The solvent compressibility calibration relies on an accurate elasticity
calibration of the pump. With a proper elasticity calibration in place, the pump
is switched into pressure control mode. A restriction capillary is connected to
the purge valve outlet. By varying the flow rate, the pump maintains a certain
pressure. The pump optimizes the compressibility value of the solvent until
the lowest possible pump ripple is reached. The pump increases the flow rate
and adjusts the pressure to the next calibration step where the pump ripple is
minimized again. This process is repeated until solvent compressibility data
for the whole operating pressure range of the pump are available.
The compressibility data set for this solvent is stored in an XML-file on the
desktop. It can be shared with other InfinityLab LC Series binary pumps via
the controlling data system.
InfinityLab LC Series 1260 Infinity II Binary Pump User Manual
Test Functions and Calibration

Binary Pump Solvent Compressibility Calibration

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