Model Meanings of YB -400 M 1 2 Y: Three-phase Induction Motor B: Explosion-proof/ Flameproof -400: Frame Size(Shaft Height) M: Frame Length symbol (S,M,L) 1: Core code (1, 2) -2: Poles Description of High Voltage Explosion-proof Three-phrase Induction Motor YB 400-450 series: This YB400-450 series flameproof/ explosion-proof three-phase induction motor adopts an internal circulation and ventilation cooling mode, and according to the operational requirements this explosion-proof motor also can be made into ExdI and ExdIBT4 type, whose safety performance fully conforms to Chinese Standard GB3836< Electrical Apparatus for Explosive Gas Atmosphere>. Characteristics of High Voltage Explosion-proof Three-phrase Induction Motor YB 400-450 series: This explosion-proof motor is characterized by a high efficiency, excellent performance and reasonable flameproof structure. Applications of High Voltage Explosion-proof Three-phrase Induction Motor YB 400-450 series: 1) EExd I : This flameproof motor can be used in the underground coal mines where the explosive mixture such as methane or dust exists. 2)EExd II BT4: This explosion-proof motor we manufactured in China can be used in sites where the hazardous environment is classified into II Group, B Class, and Temperature T1-T4. Working Conditions of High Voltage Explosion-proof Three-phrase Induction Motor YB 400-450 series: 1) Ambient temperature will change according to different seasons, but it should not surpass 35 (under coal mine) or 40 (factory), the lowest ambient temperature should be -15; 2) Local altitude should never surpass 1000m; 3) The maximum air relative humidity should be lower than 95%(while temperature keeps at 25)(under coal mine) or the monthly maximum mean relative temperature of the most humid month should be 90%, and meanwhile the lowest temperature of this month should not over 25 (factory). 4) Rated voltage is 6000V and 10000V and can generate specific voltage; 5) Rated frequency is 50Hz and can also be 60Hz