1. Bearing
When the motor leaves the factory, the inner cavity of the bearing has been filled with one-half to one-third of the No. 3 lithium grease, and the same or equivalent grease should be used for re-lubrication as far as possible. There is a straight-through pressure into the oil cup in the outer bearing cap. In order to prevent the oil filling in the bearing cavity, the waste oil should be removed after loosening the bearing cap screw.
2. Commutator
The motor commutator has been ground by the manufacturer before leaving the factory, and if there is no damage during transportation, it does not need to be ground again when driving for the first time. Only in the case of foreign corrosive circulating air erosion and long-term low load operation in dry circulating air, it is easy to be worn and need to be reground. Re-polishing must be in the motor running and cold conditions, as far as possible to lift the brush. Stick silicon carbide emery cloth on a concave board or rubber block that is consistent with the outer circle of the commutator (steel emery cloth is not allowed). For the non-round commutator, it is necessary to use a sharp turning tool on the lathe, and the minimum allowable diameter of the commutator is marked on the side of the commutator. After the car is finished, use a file or high-speed steel saw blade to cut 1 to 1.5mm of mica between the reversing pieces, and then manually clean the chamfer, remove burrs and impurities, and polish the surface again, paying attention to the surface is not polluted.
3. Brush
For the small power motor using the whole brush, for the electrical or mechanical conditions of the motor is used with shock-proof liner split brush, brush selection principle, is to get good commutation performance and operational reliability.

In the case of long-term overload, it will aggravate brush wear, deteriorate brush commutation performance, and increase the trend of uneven current distribution.

c, brush pressure, for general medium power and high power motors, the installation site vibration is not large occasions, the correct pressure of the brush is (1.5-2) X 10 Pa.
d, life, brush life mainly depends on the load and air circulation. When the air humidity is 6 to 12 grams per cubic meter of water, the normal wear of 1000 working hours can be up to 5mm. Because the pollution of air humidity or circulating humidity air has a great impact on the characteristics of the "carbon brush commutator", although the load is normal, the wear amount will fluctuate by about 100%.
e, the formation of scratches, brush cross sections are determined by the rated parameters, for a light load brush (that is, long-term operation at low load) may produce scratches, which can reduce the number of brush rods, which can improve the current density of the working brush and prevent the formation of scratches. If the measure is impossible or ineffective. The manufacturer must be consulted. The brush on the original motor is ground, and it is usually not necessary to grind it again in the motor debugging, but the activity of the brush in the brush grip and the spring force of the pressure finger should be checked again before use (about [1.52] X 10 Pa). In: The brush wear rate must be mastered during operation, and the brush lead line must be prevented from touching the surface of the commutator.