BRUSH NOISE

Brush Noise

1.       This information is provided to illustrate some of hte brush noise sources that may be exploited in the spirit of predictive maintenance.

COPPER BRUSHES

2.       Copper Brushes. There are 3 sub-types including sacrificial, dynamic and fallback brush.

3.      One of the most commonly encountered copper brush is the Acme 7000, commonly first observed on oscillosope D124

Figure 1. Oscilloscope C

4.       When seen on Oscilloscope C, copper brushes failure indicators appear as horizontally spaced lines that often increase and decrease.