TSI Instruments SIZER EEPS 3090, Руководство по эксплуатации и обслуживанию

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Product Overview 1-7
Analog Voltage Out Channels 1
–4
In addition to RS-232 serial communications for data transfer, particle
concentration can be output by the EEPS spectrometer as analog
voltages, to be readily integrated with other instruments on common
laboratory data acquisition platforms requiring analog inputs. The EEPS
spectrometer provides four
independently configurable analog channels for
this purpose. The four channels give the user the flexibility to select
different particle size ranges and different concentration weightings (e.g.,
number, surface, mass) for conversion to a proportional voltage value.
Full scale analog voltage settings are available as 0
–5 or 0–10 volts.
Entering parameters for the Analog Out feature are described in Chapter 5,
Software Operation .
A further discussion of the application of the analog feature is described in
Appendix E .
S y s t e m D i a g r a m a n d O p e r a t i o n a l O v e r v i e w
A schematic of the
EEPS spectrometer is
shown in Figure 1-5.
Particles enter the
instrument as part of
the aerosol inlet flow
through a cyclone with
a 1 µm cut. This
removes large particles
that are above the
instrument's size
range. Next, the
particles pass through
an electrical diffusion
charger in which ions
are generated. These
mix with the particles
and electrically charge
them to provide a
predictable charge
level based on particle
size. The charger is
mounted inline with the
analyzer column and
located at the top of
the instrument.
Figure 1-5
Schematic Diagram of the Model 3090 EEPS
Spectrometer