FFT spectrum analysis Among methods for viewing vibration and
noise signals and pinpointing the causes, a Fast Fourier
Transform (FFT) spectrum is perhaps the most useful. Vibration
and noise signals are broken down into specific amplitudes at
various frequencies. Because each equipment component vibrates
at a certain individual rate, maintenance personnel by
processing these signals can distinguish between several
different rates and then determine which rate coincides with
which component. The resulting FFT spectrum can point the way to
the location, cause and stage of a problem. Figure 2. Portable
unit stores and analyzes data which also can be uploaded to a
computer for more detailed analysis. User-friendly FFT analyzers
have been developed to measure vibration and noise signals and
separate them into their component frequencies. These tools can
display spectrum information in simplified formats to enable a
first-pass diagnosis of machinery condition or identify areas
for further scrutiny (Figure 3). The