BERTHOLD TECHNOLOGIES LB 567, Руководство пользователя

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Chapter 3. System Description
MicroPolar 2 (++) LB 567 17
Compensation In addition to the water content, the product temperature,
product density and a varying material load (varying microwave
irradiation path) may have an influence on the phase and atten-
uation. This influence has to be compensated for during calibra-
tion.
3.3
Temperature Compensation
Temperature compensation (TC) is required for fluctuating prod-
uct temperature. It is generally advisable to provide a tempera-
ture compensation, i.e. a temperature signal (0/4...20 mA or
PT100) to be connected to the evaluation unit and, optionally, to
enable the compensation in the evaluation unit. The evaluation
unit is designed so that the required TC’s can be calculated auto-
matically. The variation in temperature where TC becomes abso-
lutely essential is dependent on the product and on the water
content. In the first approximation,
±
2° C should be set as fluc-
tuation limit.
For example, if the product temperature is measured via the
PT100 input, then Eq. 3-1 is expanded as follows:
Measured value = A · Phase + D · T
meas
+ C Eq. 3-2
where:
Measured value Concentration / Moisture / Dry matter
A, D, C Coefficients of the calibration function
T
meas
Product temperature
How to work with the temperature compensation is described in
detail in the Software Manual.