On machinery operating under variable speed, vibration analysis with HD Order Tracking provides reliable data and crystal clear measuring results even when RPM varies greatly during the course of measurement.

Handling machines controlled by speed

More and more machines becomes controlled by speed, for example compressors with variable speed drive (VSD) where RPM changes very quickly. HD Order Tracking is applicable in a very wide RPM range, from just a few to thousands of revolutions per minute.

 

HD Order Tracking Effect

 

The method uses multiples of rotational speed (orders), rather than absolute frequency (Hz). The purpose of using orders is to lock the display to the rotational speed (1X) and its multiples, which means that the ordered components in the spectrum always remain in the same position in the display even if the rotational speed varies during measurement.

Two or several spectra from the same machine with variable speed can therefore more easily be compared if they are expressed in orders. Using order tracking, the frequency range will always cover the symptoms of interest, regardless of the rotational speed of the machine.

HD Order Tracking is approximately ten times better than traditional order tracking algorithms when RPM is not perfectly stable.