Bandwidth

The wider the bandwidth is, the better results are. However, at very low RPM, the order curves are so close to each other that the integration interval can include points produced by a neighboring order curve. For that reason, 2 different types of bandwidth are available: the bandwidth can either be constant for any RPM or proportional to the RPM. This is illustrated by the figures below. Note the specific display (orientation and coloring) in these figures: this corresponds to and top view and to the use of a log scale on Z axis.

Figure 30: Constant bandwidth

proportional bandwidth

Figure 31: Proportional bandwidth

A constant bandwidth is set by selecting the Hz unit, whereas a proportional bandwidth is set as a percentage of the current RPM.