Fault detection and diagnostics of rolling element bearings are important and relatively mature techniques used in current vibration-based condition monitoring. Despite this, since for many machines the bearing is often one of the most critical parts, improving the techniques are still interesting. The squared envelope spectrum is one of the most important tools for diagnosing roller element bearings. For a precise and correct estimation of the squared envelope spectrum, it is often important to remove harmonics not related to the bearing, as part of the signal processing prior to computing the envelope spectrum. In real-life measurements, harmonics can be caused by many kinds of sources, motors, gear boxes, and pumps are some examples of that. In the present paper, a recently proposed method for automated harmonic removal based on frequency editing is examined. The results from this method are compared with the established method for harmonic removal, the automated cepstral editing procedure. Differences between the methods and what effects they have on the computed squared envelope spectra are examined. The examination is conducted on a simulated bearing signal with a fault on the outer race.
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