BF fan box overview 

1.1.BF fan box impeller with Forward Curved multi-blade impeller and low noise external rotor motor, the motor with impeller direct coupled, low fan noise than belt-driven fan box. Wind turbine installation-horizontal (w) and vertical (l) in two ways. 1.2. to meet the requirements of different places of noise, wind machines can be equipped with different length of the muffler, fan noise box can also be thickened, the fan noise lower.