... , specialized production facilities and advanced inspection instruments.Depending on professinal R&D team, high efficiency production lines and scientific management, " ... on fan, Vibration speed virtual value of fans ≤0.5 mm/s High stabitility: we test every fan and blowers ... S: Three-phase3. 68: Motor air gap diameter4. L20: Core length code5. P2: Motor pole number6. 140 :Fan Impeller diameter7. 2 ...