Dakota MAX II, Operation Manual

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zero and produces only a load factor. Why are both options needed? In applications
where a small amount of load is applied to the fastener, thus producing very little
elongation, the regression option can potentially produce non-linear results. In cases
such as these, a vector may sometimes produce better results as the offset is set at
zero. It is recommended to use and compare both results, following a field
calibration, to determine which method is most suitable for the application and
producing the best results.
11.3 Performing a Field Calibration
This section outlines the necessary procedures to perform a field calibration to
determine a Load Factor and Offset (in the case of using regression). In the
calibration procedures below, three sample bolts will be used with three loads applied
to each bolt (1/3, 2/3, & max). This should be considered the minimum requirement
when performing a field calibration.
Creating a Group Name to Document Field Calibration Data
Applied
Load
(Measured
by Tensile
Machine)
Elongation (in time as measured by MiniMax)
At low loads, vector
can be more accurate
Vector
Regression