Time At Level (One Dimensional) - HBM SomatXR CX23-R User Manual

4 Setting up and running a test
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Number of bins: Specify the desired number of bins in the histogram. For the
Range-Mean and the To-From histogram modes, the value is 500 and applies to
both dimensions. For the Range only mode, the value is 10000.
The total number of bins per dimension is the user-specified number of bins plus
two for underflow and overflow bins. For the range-mean and to-from histogram
modes which have two dimensions, the total number of bins for the DataMode is
the product of the total number of bins for each dimension.
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. All channels selected must have the same
sample rate.
Rainflow cycle counting algorithm
Rainflow counted cycles are typically used in low cycle fatigue damage analyses.
The rainflow counting algorithm is based on the "one-pass" algorithm described in the
paper Simple Rainflow Counting Algorithms, International Journal of Fatigue,
January 1982, by D. Socie and S. Downing. The algorithm described in this paper
generates the set of closed cycles for the input peak valley sequence, assuming that
the sequence repeats itself.
However, to support proper "rainflow histogram addition" (that is, generating a
composite rainflow histogram from multiple rainflow histograms defined in a specific
sequence), the system stores both the sequence of unclosed reversals and the
histogrammed set of closed cycles in the Rainflow DataMode.
4.6.9 Time at level (One Dimensional)
The Time at level (1D) DataMode™ stores one-dimension Time at level histograms
in the output data file. Specify multiple input channels to generate multiple one-
dimensional Time at Level data channels.
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
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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.
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a4275-8.0 en HBM: public
(Page 197) about storage area for histogram
CX23-R and EX23-R