Specifications

Section 6. Data Table Declarations and Output Processing Instructions
RainFlow (Source, DataType, DisableVar, MeanBins, AmpBins, LoLim,
PuLim, MinAmp, Form)
Parameter
& Data Type
Enter
Source
Variable
The variable that is tested to determine which bin is selected
DataType
A code to select the data storage format.
Constant
Alpha Code Data Format
IEEE4 IEEE 4 byte floating point
FP2 Campbell Scientific 2 byte floating point
DisableVar
Constant,
Variable, or
Expression
A non-zero value will disable intermediate processing. Normally 0 is entered so all inputs
are processed. For example, when the disable variable is ≠0 the current input is not
included in the histogram. The histogram that is eventually stored includes the inputs that
occurred while the disable variable was 0.
Value Result
0 Process current input
≠ 0
Do not process current input
MeanBins
Constant
This parameter allows sorting by the mean value of the signal during a stress strain cycle.
The number entered is the number of bins or subranges to sort the mean values into.
Enter 1 to disregard the signal value and only sort by the amplitude of the signal. The
width of each subrange is equal to the UpLim - LoLim divided by the number of bins.
The lowest bin’s minimum value is the low limit and the highest bin’s maximum value is
the High limit
AmpBins
Constant
The number of bins or subranges to sort the amplitude of a stress strain cycle into. The
width of each subrange is equal to the UpLim - LoLim divided by the number of bins.
LoLim
Constant
The lower limit of the input signal and the Mean Bins.
UpLim
Constant
The upper limit of the input signal and the Mean Bins.
MinAmp
Constant
The minimum amplitude that a stress strain cycle must have to be counted.
Form
Constant
The Form code is 3 digits - ABC
Code Form
A = 0
Reset histogram after each output.
A = 1
Do not reset histogram.
B = 0
Divide bins by total count.
B = 1
Output total in each bin.
C = 0
Open form. Include outside range values in end
bins.
C = 1
Closed form. Exclude values outside range.
101 means: Do not reset. Divide bins by total count. Closed form.
This instruction processes data with the rainflow counting algorithm, essential
to estimating cumulative damage fatigue to components undergoing
stress/strain cycles.
The output is a two dimensional Rainflow Histogram. One dimension is the
amplitude of the closed loop cycle (i.e., the distance between peak and valley);
the other dimension is the mean of the cycle (i.e., [peak value + valley
value]/2). The value of each element (bin) of the histogram can be either the
actual number of closed loop cycles that had the amplitude and average value
associated with that bin or the fraction of the total number of cycles counted
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