Rainflow - HBM SomatXR CX23-R User Manual

4 Setting up and running a test
72
One shot: Store a single data sample when the trigger channel transitions from
o
FALSE to TRUE or if the trigger channel is TRUE on the first sample of any
run.
Trigger channel: Select the logical input channel for triggering - when using a
trigger option other than Always on. The trigger channel must have the same
sample rate as the selected input channels.
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.
DataModes options
Hysteresis level: Specify the desired hysteresis level for the peak valley
processing algorithm. See
explanation of the effect of the user-defined hysteresis level. There are two modes
for defining this:
A floating point value: The value must be greater than or equal to 0.0. This
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value is used as the hysteresis gate for all channels.
A floating point value followed by the '%' character: The value must be in
o
the range of 0.0 to 100.0. For each channel the hysteresis gate is computed
using the equation: (pv_hysteresis * (range_max – range_min) / 100.0).
Histogram mode: Select one of the three available modes.
Range-Mean - Accumulate counts in bins with range and mean dimensions.
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Range only - Accumulate counts in bins with only a range dimension.
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To-From - Accumulate counts in bins with to and from dimensions.
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Type: The only option is Evenly divided. All bins are the same size, computed as
(High bound - Low bound) / Number of bins.
Histogram bounds: Enter the desired Low bound and High bound for each
selected input channel. If the range min and max parameters are defined for an
input channel, those values are used as the default Low bound and High bound
values for the histogram.
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.
4.6.8 Rainflow
The Rainflow DataMode™ stores multiple channels of rainflow cycle 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-specified
hysteresis value and the peak valley processing algorithm. The resulting peak valley
stream runs through the rainflow cycle counting algorithm to yield the set of closed
a4275-8.0 en HBM: public
Peak valley processing algorithm (Page 71) for an
CX23-R and EX23-R