Endress+Hauser Gammapilot M FMG60, Руководство по эксплуатации

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Commissioning Gammapilot M FMG60 PROFIBUS PA
62 Hauser
Empty calibration
Refers to the following situation:
• The radiation is switched on.
• Within the measuring range, the vessel is emptied as far as possible (ideally: 0%,
maximum 40%).
Calibration points for limit detection
A0018112
A Background calibration
B Covered calibration
C Free calibration
Background calibration
Refers to the following situation:
• The radiation is switched off.
• If possible, the radiation path is completely covered.
The background calibration is necessary, in order to register the natural background
radiation at the mounting position of the Gammapilot M. The pulse rate of this background
radiation is automatically subtracted from any other measured pulse rate. That means: only
the part of the pulse rate which originates from the applied radiation source is taken into
account and is displayed.
As opposed to the radiation of the applied source, the background radiation remains nearly
constant during the complete measurement. Therefore, it is not submitted to the automatic
decay compensation of the Gammapilot M.
Covered calibration
Refers to the following situation:
• The radiation is switched on.
• If possible, the radiation path is completely covered.
If the radiation path cannot be completely covered during the calibration, the covered
calibration can alternatively be performed with the radiation switched off, which is a way of
simulating complete covering. In this case, the covered calibration is identical to the
background calibration. As the pulse rate of the background radiation is automatically
subtracted, the displayed pulse rate is about 0 c/s.
NOTICE
This type of simulated calibration is not possible with self-radiating media. In this case
it is always necessary to perform the background calibration and the covered
calibration with the radiation path completely covered.
Free calibration
Refers to the following situation:
• The radiation is switched on.
• The radiation path is completely free.
A B C
OFF ON ON