Top plot: Pump rotation speed, on cyclic on-off operation.
Middle plot: The bearing fault Xfactor, plotted in relation with the pump speed in top plot.
Bottom plot: The bearing fault severity level plotted.

The existence of a none-zero Xfactor is a strong indicator of a bearing fault issue. The severity level expresses the actual bearing fault severity level, normalized with the initial bearing fault severity level.

This case shows a bearing fault Xfactor = 4.08 when the pump is running. The pump has bearing type SKF6308, and the datasheet states a ball spin frequency BSF = 4.078). It also shows a Xfactor = 8,20 due to double impact frequencies as the point of damage hits both inner and outer race during one rotation.