Berthold castxpert LB 452, Руководство по эксплуатации

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c
7 "Channel Overview" Menu
b
Rev. 04, 03/2015
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7.2.1.1 Adding and Changing Calibration Points
For correct calibration, at least two points (usually 0% and 100%) are required.
An empty mould and a mould with a cold block are usually used to determine the
count rate at 0% or 100% fill level.
In order to increase the accuracy of the measurements, the natural background
radiation (background level) can be offset.
A multi-point calibration is always possible for increasing the accuracy of measure-
ments and for factoring in any profile non-linearities if needed. When using an
activity-optimised radiation source (AOS), this is indispensable. In this case, you
must also calculate a calibration point at a fill level of 50%.
The activity-optimised radiation source (AOS) enables the increasing of accuracy in
the upper part of the measurement range - where a higher level of accuracy con-
tributes to an improvement in quality.
An increase in accuracy can be achieved through optimised-activity distribution
without an increase in radiation activity being necessary for this. On the other
hand, if the current measurement accuracy is retained, the radiation activity can
be significantly reduced.
Note
If it is not possible to use a cold block which simulates a fill level of
50%, then use the count rate which was used in the reading of the
AOS. You can find this in your documents.
1. In the "Channel Overview" menu click on Settings | Calibration ( Fig. 54).
2. Mark the pair of values to be changed (calibration point) by clicking on the
corresponding field (Fig. 55, Pos. 7).
3. Click on <Change> (Fig. 55, Pos. 2) or on <New> (Fig. 55, Pos. 3) if an addi-
tional point should be added.

The input field "Adapt Calibration Point" opens (Fig. 56).