MIP LM 3188, Руководство пользователя

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3) The monitor units
M 308
Range 0…3 D
LM 3086
M 318 Range 0…1 D; LCD display 0…2g/m3 LX 3188 / LM 3188
M 318AZL Range 0…1 D; LCD display 0…2g/m3 LM 3188AZL
M 318AZH Range 0…3 D; LCD display 0…20g/m3 LM 3188AZH
All monitor units have analogue meter 0 … 100 % of the selected D-value scale, voltage and
current outputs as well as alarm relay. Also controls for zero, span and mass calibration (M
318) are included as well as relay limit settings.
There are some options available for larger area detectors or modified operation ranges for
basic unit. Consult factory on these options.
1.3 APPLICATIONS FOR DIFFERENT LASER MODELS
The different laser types, obviously, address different applications. As a guideline following
information is based on practical installations:
LM 3086 Red, gas laser works best in relatively high-dust environment (>100mg/m3). It
has become a sort of standard in pulp mill applications, recovery boiler, lime
kilns, etc.
LM 3188 Semiconductor laser is used in relatively low-dust environment (< 1g/m3) or
where the space is limited.
LX 3188 Superled model can be used instead of LM 3188 where the measuring length
is short enough (<2m) or where the price is of primary importance.
2. THEORY OF OPERATION
When a monochromatic light beam, such as laser beam, traverses through gas that contains
particulate matter, the intensity of the beam will decrease by absorption and scattering pro-
cesses within the particle distribution. The net effect can be described by so called Lambert-
Beer law as (eq.1):
Where I0 is the source intensity of laser light
I is the measured intensity at the detector
x is the length of the beam passage in particle distribution

is a constant that depends on particle diameter, laser
wavelength and any absorption process present
) * (
0
x
e I I

 