Berthold MicroPolar LB 566, Руководство пользователя

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Chapter 3. System Description
18 MicroPolar (++) LB 566
3.2
Calculation of Measured Values
The microwave parameters phase and attenuation are calibrat-
ed according to an automatic plausibility analysis.
During calibration, the phase and/or attenuation of a concentra-
tion value (or density value) are assigned through sampling.
The calibration is done automatically and the sampling process
is supported by the evaluation unit.
Which of the parameters (phase, attenuation or both) will be
used for the calibration depends on the size and interference of
the measuring effect. For example, the attenuation is signifi-
cantly more sensitive to electrolytic conductivity (salt content).
In many cases, the pure phase measurement is recommended
and the measured value is calculated as follows:
Measured value = A ∙ Phase + C Eq. 3-1
where:
Measured value Concentration / Moisture / Dry matter
A, C
Coefficients of the respective calibration
function
The LB 566 allows you to calibrate, display and output two con-
centrations: Con1 and Con2. You have to enter the calibration
coefficients separately for concentration 1 and 2. For more in-
formation please refer to the Software Manual.
Limitations

Weakly bound water can be detected depending on the
strength of the binding. Thus, the measuring effect may be
dependent on the grain size distribution and the chemical
properties of the product being measured, provided this
changes the binding of water to the solid matter.

Walls made of plastic, rubber or insulation materials with
fairly low dielectricity hardly affect the measurement and are
calibrated at a constant level.

Ice and crystal water cannot be measured because the water
molecules cannot rotate freely (ice and crystal water are
dry).