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3.5.2 Sampling the measurement signals
DIGIFORCE
®
9311 supports three different sampling methods, which you can enable in combination. In
addition to time-based sampling, you can record the pairs of measured values using a configurable
Delta(Δ)X value or Delta(Δ)Y value. This allows the DIGIFORCE
®
9311 to use only the optimum number
of sample points to record a curve accurately and to reproduce it in full. For instance, it uses only a very
few points to measure a force/displacement curve that has a low gradient over the initial travel region of
the joining process followed by a steep section as it rises into an end-point force.
Diagram 4: Sampling the measurement signals
3.5.3 Defining an X-axis reference
A measurement curve recorded by the DIGIFORCE
®
9311 can be based on a choice of references. For
instance for a force/displacement curve, the reference can be a particular displacement value. In a
conventional application using an "Absolute" reference, the reference point equals the zero point of the
position measurement system. Component tolerances or tolerances in tool changeover systems,
workpiece mounts etc. result in variation (spread) in the X-values of the measurement curves. This
spread might mean that the result from an evaluation element falls in the NOK category. You can
eliminate this spread, however, by using a different reference point.
The DIGIFORCE
®
9311 provides the following reference options:
•
Absolute
•
Final force
•
Crossing reference line
•
Crossing trigger threshold.
Summary of Contents for DIGIFORCE 9311
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