Shaanxi AsynchronousSIMO MotorDocumentation:The main inspection items for motor brushes and slip rings are as follows:

      (1) The brushes and slip rings make good contact; the contact surface is free of oxide film, sparking, and abnormal noise.

　　(2) The brushes show no vibration, wobbling, or jamming in the brush holders.

　　(3) The brushes are undamaged and not excessively short (not less than 30 mm).

　　(4) Compression springs are neither dislodged nor broken. The compression spring pressure for each brush shall equal the original value [: (2 × 5.887) N, measured with spring-balancing equipment].

　　(5) Connections are indeed complete and secure; clamping screws show no looseness or detachment; there is no heating or contact with the housing.

　　(6) Brush holders and brush gear must be cleaned thoroughly; if scale buildup is severe, contact maintenance personnel to blow clean using a blower.

　　(7) [[E6]] The brushes and slip rings show no overheating or discoloration; slip ring surface temperature does not exceed 120 °C, and slip ring outlet temperature does not exceed 65 °C.