In the sliding bearing lubricated by the oil ring, the amount of oil in the bearing should be constant, and it is generally not filled with oil during operation. When the amount of oil is below the specified liquid level, the bearing should not throw oil to avoid splashing on the windings.

Motors with ball or roller bearings need to be replaced once when running for about 2000 hours. When the bearing is used in a dusty and humid environment, the lubricating oil should be changed frequently according to the situation.

Before starting a generator that has been out of use for a long time: if a rolling bearing is installed, its lubrication state must be checked first. If the original grease is dirty or hardened and deteriorated, the bearing must be rinsed first, and then cleaned with gasoline. Fill with clean grease very late. The filling amount is 2/3 of the bearing chamber space, and it is not allowed to fill too much.