Good sign for carbon brushes

Carbon brushes, also called electric brushes, are widely used in many electrical equipment as a sliding contact. The main materials used for carbon brushes in products are graphite, greased graphite, and metal (including copper, silver) graphite. A carbon brush is a device that transmits energy or signals between the fixed part and the rotating part of a motor or generator or other rotating machinery. It is generally made of pure carbon and coagulant. There is a spring to press it on the rotating shaft. When the motor rotates, the electric energy is sent to the coil through the commutator. Because its main component is carbon, called carbon brush, it is easy to wear. It should be regularly maintained and replaced, and the carbon deposits should be cleaned up.
In order to ensure the normal operation of the motor, the signs of good carbon brush performance should be:
1) A uniform, moderate and stable oxide film can be quickly formed on the surface of the commutator or collector ring.
2) The carbon brush has a long service life and does not wear the commutator or collector ring
3) The carbon brush has good commutation and current collecting performance, so that the spark is suppressed within the allowable range, and the energy loss is small.
4) When the carbon brush is running, it is not overheated, the noise is small, the assembly is reliable, and it is not damaged.