Peak Valley Matrix - HBM SomatXR CX23-R User Manual

CX23-R and EX23-R
Channel select: From the channels list, select the desired input channels for the
DataMode and click the appropriate arrow. Alternatively, drag and drop the desired
channels to the appropriate list.
Peak valley processing algorithm
After initializing, the peak valley processing algorithm alternates searching for peaks
and valleys based on the user-defined hysteresis. There are three states of the
algorithm - initialize, peak search and valley search.
Initialize: The algorithm tracks the minimum and maximum input values until the
difference between them exceeds the hysteresis level. If the minimum value
precedes the maximum value, the minimum is the first stored valley and the
algorithm switches to Peak search. If the maximum value precedes minimum
value, the maximum is the first stored peak and the algorithm switches to Valley
search.
Peak search: The algorithm tracks the maximum value as a candidate peak and
minimum value as a candidate valley. When the difference between the candidate
values exceeds the hysteresis level, the candidate peak value is stored. The
algorithm switches to Valley search.
Valley search: The algorithm tracks the minimum value as a candidate valley and
maximum value as a candidate peak. When the difference between the candidate
values exceeds the hysteresis level, the candidate valley value is stored. The
algorithm switches to Peak search.
4.6.7 Peak valley matrix
The Peak valley matrix DataMode™ stores multiple channels of peak valley reversal
histograms in the output data file. The CX23-R/eDAQXR acquires peaks and valleys
from triggered or un-triggered time history data streams using the user-defined
hysteresis value and the peak valley processing algorithm. The resulting peak valley
stream defines the set of peak valley reversals which are histogrammed using the
user-defined options for the type and size of histogram.
NOTE
The cumulative size of all histogram matrices across all Rainflow, Peak Valley
Matrix and Time at Level DataModes is limited to 50 MB. This is sufficient for
storing over 600 one dimensional histograms using 10000 bins. It is also
sufficient for storing over 600 two dimensional histograms using 100 x 100 bins.
See SIE file size issues
DataModes.
Trigger mode: Select one of four available triggering options. Use triggering to
eliminate undesired segments of the input data stream before it is processed by
the DataMode.
Always on: Do not use triggering. Data storage is always on from the start of
o
the test.
Trigger: Data storage starts when the trigger channel becomes TRUE and
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continues until the test run stops.
Gate: Data storage occurs when and only when the trigger channel is TRUE.
o
a4275-8.0 en HBM: public
(Page 197) about storage area for histogram
4 Setting up and running a test
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