The condition of the coupling system of several motors of a sewage treatment plant (which was based on gear reducers) was diagnosed using a combined MCSA and ATCSA analyses.

In some of these motors, prominent components linked to gear wear or damages appeared in the MCSA spectra:

The application of ATCSA enabled to confirm the presence of the anomaly:

Periodic trending is recommended in this case to analyse the deterioration of the gear reducer condition over time.