Bench Testing: Brushes
Inspect brushes for free movement in holder. Clean brush holder if necessary. Check brushes for cracks and wear. Check brush springs for corrosion or damage. Ensure brushes are not worn beyond minimum length (limit mark scribed on brush). If brushes do not have scribed minimum length mark, ensure brush length exceeds minimum specification. See MINIMUM BRUSH LENGTH table.
MINIMUM BRUSH LENGTH
| Application | In. (mm) |
|---|---|
| Hitachi | .236 (6.0) |
| Mitsubishi | .197 (5.0) |