In greaseless electric motors, lubrication must be performed as described in the existing preventive maintenance plan. The disassembly and assembly of this type of motor must be made according to the specifications described by the manufacturer. Electric motors with shielded bearings require their bearings to be automatically replaced when they reach the end of their grease life.
In the case of motors with grease fittings, at the precise moment of relubrication of their bearings with the engine stopped, it is necessary to thoroughly clean the vicinity of the grease entry holes. It is extremely important that approximately half of the recommended total grease is placed on the nameplate of the engine, and thus cause the engine to rotate for about one minute at the rated speed.
The engine must be switched off so that the remaining grease can be put in place and, afterwards, replace the grease guard. For the relubrication process of the bearings at the moment the engine is in operation, it is important that the person responsible for the action is careful to clean the vicinity of the grease entry hole and, as in electric motors without grease. https://www.mrosupply.com/automation/ac-variable-frequency-drive/697987_vs1md43-8_baldor/