User's Manual

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Version 1.4
In the context of leakage noises, the goal of the correlation measurement is
primarily to determine the propagation time difference of two signals.
Because the correlation curve also includes spectral information, it is often
of interest to define the character of the leakage noise, particularly for
distinguishing noises that are not related to the leak, provided this can be
detected by means of a frequency analysis (e.g., electrical noise). The
correlation curve can also be mathematically filtered for the purpose of
retroactively separating such interfering noise to better identify the
correlation maximum caused by the leak.
Figure 12 Correlation Spectrum
The correlation spectrum is a combination of the signal spectra of the two
sensors, which is used for the correlation on the pipeline between the two
sensors. In these common spectra, it may be possible to identify the
influence of noises not related to the leak (e.g., electrical noise or pumps)
on the correlation result (see also 2.2.2 Graphs - Signal spectrum).
2.2 Leak Values tab
Displayed in the Leak Values list area are all values that are needed for an
evaluation.
2.2.1 Table fields
Reference number of the displayed logger.
The Location field is a text field in which the location of the logger, e.g., the
Correlation spectrum
Logger No.
Location