When this acceleration measurement is
processed with appropriate software, more
information is revealed (Figure 4). It is
typical to view rotating machinery data in a
“waterfall” format where the horizontal axis
is the order number (multiples of shaft
rotational speed), the vertical axis is rpm,
and the amplitude is a color scale. Here a
cursor is laid on the 9th order, which has
the highest response. The amplitudes along
this cursor are displayed in the upper strip
on the graph. This strip shows the amplitude
of this 9th order vs. rpm.
