FISCHER FISCHERSCOPE X-RAY XDLM 231, Operator'S Manual

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Calibration of X-ray fluorescence measuring instruments Measurement device monitoring for the Fischerscope X-RAY
FISCHERSCOPE
®
X-RAY 107
15 Measurement device monitoring for
the Fischerscope X-RAY
According to quality management guidelines, all measuring
instruments are subject to measurement device monitoring.
FISCHER, as a manufacturer of measurement instruments,
accounts for this and sees to it that customers who require advice
and support are able to properly use their measurement
instruments. The users of our instruments are companies all of
whom are essentially certified according to the DIN EN ISO 9000
QS Standards. They are required to perform quality management
and thus also plan, carry out and document measurement device
monitoring. We will offer some pointers below. These
recommendations can then be adopted either in part or in full into
the quality management manual in the form of process or test
instructions. Of course, they apply analogously to instruments of
other manufacturers.
15.1 Calibration of X-ray fluorescence
measuring instruments
With X-ray fluorescence measuring instruments (DIN 50987, ISO
3497), the displayed readings are calculated from the spectrum of
the fluorescence radiation.
Measurement applications define the
structures and features of the samples to be measured (order and
composition of the coatings and of the substrate material, quantities
to be measured), provide the spectra evaluation and set the
instrument to the intended measurement parameters, e.g., to the
operating voltage of the X-ray tube
.
The expression ”calibrating”
NOTE: In the context of this recommendation, ”calibrating” in
the spirit of the instrument technology refers to an
”adjustment”. In the instrument technology, re-mea-
suring the calibration standards in order to verify that
the readings obtained with the measurement applica-
tion are still correct is referred to as ”calibration”. Still,
for practical and historical reasons and for the neces-
sary agreement with the Standards DIN 50987 and
ISO 3497 (Coating Thickness Measurement Using X-
ray Fluorescence) we will continue to use these once
selected designations, especially since these desig-
nations are also used in the software of the instru-
ments.
Each measurement application is calibrated with calibration
standards that should in their structures be as close as possible to
the sample but may, however, differ from the samples in their