Principle Of Operation; Display Screen Groups - CASELLA CEL CEL-712 User Manual

CEL-712 Microdust Pro Real-time Dust Monitor

2.1 Principle of operation

The Microdust Pro instrument uses a modulated laser light source passing into
a measurement chamber.
Figure 2 Sampling probe
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1
1. Laser source
2. Sample volume
3. Optical detector
4. Light stop
Under clean-air conditions, all light is prevented from following a direct route
to reach the laser detector (3) by a light stop (4). When dust particles enter the
sample volume (2), the beam of laser light is scattered within a narrow angle
and some of it can reach the detector by indirect routes.
By using a narrow angle of scatter, the instrument is made less sensitive to
variations in the refractive index and colour of measured particulate.

2.2 Display screen groups

The Microdust Pro instrument has groups of screens that allow you to set up
and operate the instrument, and to see the results of the instrument's
measurements. The screens have colour-coded bars at their top and bottom
edges to help you identify which screen group they belong to. Refer to
coding on page 5. Figure 3 below also shows the colour codes together with the
way the screen groups relate to each other.
Note that the contents of some screens may vary, depending on the variant of
instrument you are using.
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9
31
1
41
Colour
Casella Measurement