Endress+Hauser Gammapilot M FMG60, Руководство по эксплуатации

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Gammapilot M FMG60 PROFIBUS PA Commissioning
Hauser 71
Multiple-point calibration
The multiple-point calibration is recommended particularly for measurements in a large
density area or for especially exact measurements. Up to 9 calibration points can be used
about the whole measuring range. The calibration points should be located as far from each
other as possible and should be uniformly distributed over the measuring range. After the
calibration points have been entered, the Gammapilot M automatically calculates the
parameters I
0
and  . Multiple-point calibration is especially advisable for measurement in a
wide range of densities or for especially precise measurements.
Recalibration
The Gammapilot M provides a further calibration point ("10") for recalibration. This point
can be entered, if the measuring conditions have changed, e.g. by deposit in the measuring
tube. After entering of the recalibration point, I
0
is recalculated according to the current
measuring conditions. The absorption coefficient  is kept unchanged from the original
calibration.
Methods for entering the calibration points
Automatic calibration
For an automatic calibration, the desired calibration point is realized at the measuring tube,
i.e. the measuring tube is filled with a medium of the desired density. For the background
calibration the radiation remains switched off, for the other calibration points the radiation
is switched on.
The Gammapilot M automatically records the pulse rate. The associated density is
determined in the laboratory and entered by the user.
Manual calibration
In order to achieve a high measuring accuracy, it is advisable to determine the pulse rates for
a couple of samples of the same density and to calculate the average density and average
pulse rate for these samples. These values can then be entered manually into the
Gammapilot M.
If possible, this procedure should be repeated at a further density. The both density values
should be as far from each other as possible.
NOTICE
When calibrating manually, the calibration date is not set automatically. Instead, it
must be entered manually into the "calibration date" (*C7) function.