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

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Pre-run for determining the control limits Measurement device monitoring for the Fischerscope X-RAY
FISCHERSCOPE
®
X-RAY 119
With a Fischerscope XRAY with WinFTM software, the spectra of
the ”pure elements” are not measured anew during the
normalization but instead are accepted from the spectra library that
contains their spectra when the switch ”Measure elements” of the
DefMA is disabled. In this manner, the measurement application is
not changed during normalization, and therefore not corrected,
except for a potential substrate material correction. For such
measurement applications, normalization cannot provide any new
information.
The measurement application should be checked once more after
every corrective measure. If the limits are still violated, we
recommend a re-calibration of the measurement application. Due to
its high stability, corrections of the measurement applications of a
Fischerscope XRAY are typically required only after several weeks
or months.
NOTE: Note: All measurements for monitoring of the mea-
surement devices as well as all potential corrections
should only be performed once the instrument has
been measuring for a sufficient length of time, that is,
it has generated ”radiation”. 15 – 30 min of operating
time are sufficient for this purpose. Thus, measure-
ment device monitoring is not recommended directly
after power-up of the instrument, even though regular
measurements can be made.
15.9 Pre-run for determining the control limits
NOTE: Note : The equations and factors used here are all de-
scribed in the equation collection of the operator’s
manual for the Fischerscope XRAY. The control limits
can be calculated using the ”calculator” functions in
the control chart of WinFTM. Beyond that a spread-
sheet that contains the equations beneath for the cal-
culation of the control limits can be used for the pre-
run.
The pre-run consist of a minimum of m = 10 groups each with
n = 5 single readings, i.e., a total of 50 measurements. The
measurement application and the identity designations must be
documented.
The single readings for the pre-run should be carried out
successively using the setting parameters (measurement time,