horiba LO-300, Инструкция по эксплуатации

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Overview
2
Detection principle
The light reflected from the water surface is dependent on the refractive index of the surface
material. If the surface is covered with oil film, the oil will reflect light more than that of water
surface, because the refractive index of the oil is higher than water. The intensity of the light
reflected from the surface suggests the oil on the water.
The oil detection system by light reflection method needs large detection area to get the mean
reflection that is the instrument needs large caliber lens and detector because the local wave
of the water scatters the incident light.
The LO-300 scanning laser system matches the request to detect oil on the water, the small
size of trunk covers large detection area from a distance. Moreover this system can measure
the oil covering ratio by the reflection time scanning. The laser scanner module rotating
around the optical axis could reject local light scattering by the wave ripple and detect mean
intensity of the reflection from the surface.
Fig. 1 LO-300 detection principle
Detectable oil types
Followings are the conditions of detectable oils. Table 1 shows typical oil types.

Oils not dissolved in the water.

Oils lighter than the water and spread on the water.

The refractive index is higher than 1.4.
Table 1 Detectable oil types (typical example)
Motor
Photo detector
Lens
<Detection area>
Laser module
Signal
processing
4 mA to 20 mA output
Oil film alarm
contact output
Error contact output
Gasoline Lubricating oil
Kerosene Cutting oil
Diesel fuel Toluene
Crude oil Vegetable oil
Insulation oil