Introduction To The System - Agilent Technologies SD-1 User Manual

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Introduction

Introduction to the System

Introduction to the System
The Agilent SD-1 is an innovative HPLC solvent delivery system engineered
with preparative chromatographers in mind. Corrosion-resistant titanium
pump heads address the needs of biochemists for compatibility with
salt-containing buffers and freedom from unwanted metal ions. Each pump
head has a piston washing chamber to prevent deposition of abrasive salt
residues behind the high-pressure seal, thereby greatly extending seal life.
Major new technology includes dual independent linear piston drives. Rather
than operating both heads from cams attached to a single motor, as in
conventional dual piston pumps, the Agilent SD-1 uses two independent
stepper motors which connect to pistons via linear screw drives. The motors
reciprocate, rather than running only in one direction. Independent drive
frees the Agilent SD-1 from the operating constraints of mechanical cam
profiles and makes it the first dual piston pump to produce entirely pulse-free
flow under all operating conditions, without auxiliary hydromechanical pulse
dampers. Totally pulse-free flow favors improved column performance and
extended column life by saving expensive preparative columns from the
constant pressure-pulse pounding typical of other large piston and diaphragm
pumps.
In addition, the Agilent SD-1 meters flow at a constant rate independent of
solvent compressibility and without the slight refill-associated flow deficits
seen with conventional single-motor dual-piston models. In gradient
operation, this produces more precise composition profiles without the time
and volume delays introduced by large mixing chambers. Plus, flow rates
extend well into the analytical HPLC range, permitting method development
on smaller columns without interchanging heads.
Each Agilent SD-1 pump includes a standard serial interface for flow control.
A built-in two-channel analog-to-digital converter allows the computer to
collect data from HPLC detectors. Contact closure inputs and outputs are
provided for system automation. Firmware includes Good Laboratory
Practices (GLP) logging features.
8 SD-1 Solvent Delivery - User Manual