When if "220V AC Cooling Fan" physical rotor inertia centr and the center of the rotor shaft axis is not the same, it will cause the rotor imbalance. The physical distance between the centroid of the nearest center of inertia of the rotor and the shaft is called the eccentricity of the rotor does not cause eccentricity value, when the rotor is rotated due to the centrifugal force generated in the shaft mount and a force of vibration is formed, and the vibration is transmitted to the base path via various parts of machinery.

"220V AC Cooling Fan" wind noise sounds only pure wind, and different sound is different, when the fan is running, in addition to the wind, but if there are other sound, you can determine the fan appeared different tone. "220V AC Cooling Fan" abnormal noise may be due to a foreign body or the bearing deformation, and collision improper assembly, or motor winding wound unevenly, resulting in loose, are likely to produce different sounds.