This series motors with box type steel structure, can be observed its interior after removing the cooler or protective cover,and esay to be installed and maintained; The cage structure rotor made by once forming process or copper strip rotor made by mid-frequency welding process, improve the reliability of the motor; Insulation class F stator made by VPI process, ensure the reliability of insulation, moisture-proof and shock resistance; Temperature senor for stator and bearing, non-stop oil filling pipeand oil exit pipe, improve the protection ability and operation efficiency of the motors.