Rockwell Automation Publication 1441-UM003A-EN-P - May 2011
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FRF Frequency Response Function Extension Module
Chapter
2
The FRF - Taking Data screen shows frequency, magnitude, phase, and Q
factor (where appropriate) at the cursor position.
Field Calibration
Data can be checked for calibration and integrity by carrying out a test on a
known mass, for example, a calibration weight or steel bar of a measured value.
Use a calibration weight of 1kg or any other known mass.
Figure 2 - Field Calibration Setup
This is an example of a set-up for Field Calibration.
1.
Fit the correct tip to the modally tuned hammer.
Indicates how many hits
were taken.
FRF Measurement
The FRF is colored red
where coherence falls
below 80%.
Good coherence shows the
trace in green.
Phase
Coherence for the
measurement, represented
by the color of the FRF
trace.
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