Endress+Hauser OUSAF46, Руководство по эксплуатации

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Product description OUSAF46
6 Hauser
3 Product description
3.1 Measuring principle
Light absorption
The measuring principle is based on the Lambert-Beer law.
There is a linear dependency between the absorption of light and the concentration of the
absorbing substance:
A = -log(T) = ε . c . OPL
T = I/I
0
T ... Transmission
I ... Intensity of received light at detector
I
0
... Intensity of transmitted light of light source
A ... Absorption
ε ... Extinction coefficient
c ... Concentration
OPL ... Optical path length
A light source emits radiation through the medium and the incident radiation is measured on
the detector side.
The subsequent conversion to absorbance units (AU, OD) is performed in the associated
transmitter.
1
OPL
2
3
4 5 6 8 7 2
A0029412
 1 Absorption measurement with reference
1 Light source
2 Optical windows
3 Measurement filter
4 Measuring detector
5 Lens
6 Medium flow
7 Reference filter
8 Reference detector
OUSAF46 has 2 pairs of reference and measuring detectors (= 2 channels). Only one
channel is shown for the sake of simplicity.