PerkinElmer 200 UV/VIS Series, User Manual

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Principles of Operation Design Considerations
8 - 6
Design Considerations
The Series 200 UV/VIS LC Detector is based on a modular design with each module dedi-
cated to an internal function. This approach makes testing and servicing convenient and
easy. If difficulty arises with a particular component, in most cases the module or sub-mod-
ule containing that component may be field replaced to minimize downtime. The basic mod-
ules of the Series 200 UV/VIS LC Detector are as follows:
Source Lamp Deuterium Lamp for UV spectrum analysis (stan-
dard). Tungsten Lamp (optional) for visible spec-
trum analysis (above 360 nm).
Monochromator Optical unit containing beam collimators and grat-
ing for wavelength selection.
Flowcell Flowcell supplied for sample path operation. (12
µ
L, 8 mm path std.)
Reference Dry Cell Dry cell supplied for reference path operation.
Stepper Motor Stepper motor attached directly to the wavelength
lead screw of the monochromator. Moves grating
under microprocessor control.
Power Supply Board Contains lamp power supplies and circuit power
supplies.
Limit Stops P.C.
Board One optical interrupter and two switches that
sense the mechanical position of the wavelength
drive system.
Display Module Four lines by forty columns alphanumeric display.
Photodetector Head Matched photodiodes and circuit board which con-
vert sample and reference light intensity levels to
electronic signals.
Signal Processor P.C.
Board Contains circuits to convert photodiode signals into
usable output voltages. Also contains microproces-
sor circuits.