BERTHOLD TECHNOLOGIES LB 480, Руководство пользователя

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SENSseries LB 480 Level measurement
BERTHOLD TECHNOLOGIES GmbH & Co. KG
2 – 157
Volume 2 1 System Description
2
1.3
Measuring Principle
The principle of measurement is the irradiation method, utilizing the
physical law of the absorption of radiation passing through matter.
The resulting measuring effect is the ratio I/I
0
between the unatten-
uated radiation I
0
and the radiation I attenuated by the product
being measured.
The mathematical correlation is as follows:
The equation shows that with a given source and the respective
mass attenuation coefficient
μ the measuring effect is dependent
only on the product density ρ and the measuring path d .
Since the measuring path is constant and possible product density
changes at a certain measuring path due to exponential reasons do
not have any effect any more, this measuring method is not
affected by any chemical and virtually no physical properties of the
product being measured. For this reason, the radiometric measur-
ing principle ensures high reliability and low maintenance.
Fig. 1-4 Measuring Principle
I = I
0
x e
- μ x ρ x d
Source Detector