Berthold LB 442, Руководство по эксплуатации

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Section 6 Evaluation Unit LB 442
61
Calculate
Calibr. Mode
Select the calibration mode.
lin/squ/cub/auto
-
lin
Linear curve fit. This mode is used when at least one calibration
point is available in addition to the tare measurement. Linear cali-
bration is the most frequently used type of calibration. For more
information see chapter 5.2.4 b) Calibration.
Square curve fit cannot be selected. Please use the cubic calibra-
tion function instead.
-
cub
A curve fit using cubic coefficients should be applied when at least
3 value pairs are available and a linear curve is not sufficient. In
this case you have to enter the maximum weight per area as well.
See also on page 54.
-
auto
The program automatically selects the best curve fit . Square or
cubic curve fit are used only when it can be ruled out with 95%
probability that the values correspond to the curve only by chance
(check by means of f-test).
If more than three calibration points are used for a calibra-
tion of the curve, then we recommend to plot the calibration
points. In this x/y plot, the load (t/h) should be a function
of the count rate LN (cps).
LN (cps) = natural logarithm of the count rate.
Upon selection of the required calibration mode and press-
ing of the < enter > button, the calibration factors are calcu-
lated.