Multiple-Fault Detection Methodology Based on Vibration and Current Analysis Applied to Bearings in Induction Motors and Gearboxes on the Kinematic Chain

Figure 10

PSD spectrum from current signal when VFD is set to 50 Hz.

(a) For the healthy condition and all wear levels

(b) For the healthy condition, bearing defect, 75% of uniform wear, and 75% of uniform wear + bearing defect