Varian ProStar 325 UV-Vis, Руководство по обслуживанию

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ProStar325 Service Manual
Publication date 8 May 2003
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variations of a common base model that can be configured for
each individual application.
If fitted with the optional Vis lamp, the detector operates across
the entire spectrum from 190nm to 900nm. Both lamps are
continuum lamps and only one should be selected at a time.
Wavelength selection is provided by a holographic grating driven
by a stepper motor drive mechanism.
A silica glass beam splitter provides double beam operation. The
two beams are individually passed through the optics system and
into the monochromator and then to their respective photodiode
detectors.
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Simplified Optical System
For increased performance the two channels are separated and
the photodiodes are connected to individual preamplifiers. The
preamplifier output voltages are directly proportional to the light
intensity hitting their active surfaces.
The outputs of the preamplifiers are digitised, processed, and
either sent to a pc, or re-converted to analog. The analog circuitry
produces a voltage directly proportional to the ratio of the sample
signal to the reference signal. This voltage is supplied to the rear
panel as the 1V/AU integrator output and as a recorder output.
For extra flexibility, the 325 detector can also be controlled via a
hand-held PPC. You can use the PPC to download, build and
store methods from the host computer, and have full functional
control of the detector via an infra-red communications link.
The detector is compatible with the current ProStar range of
products and operates under the control of the Star or Galaxie
software workstation software. Communication to the host PC is
via an Ethernet TCP/IP link operating up to 100Mbps. This high-
speed connection enables real time representation of the
spectrum displayed on the workstation. Further more, it also
allows the detector workstation to be integrated into a TCP/IP
protocol LAN to enable remote access to any detector over an
internet connection.
There are also four flowcell options for the detector at present;
Beam
splitter
lamp
sample
referenc
grating
sample reference
Photodiode
detectors
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