Different difference "Waterproof Cooling Fan" and AC fans that DC fan is based amps right-hand rule, the conductor through current produces a magnetic field around, if this conductor is placed in another fixed magnetic field, will produce suction or repulsion, caused by moving objects. In "Waterproof Cooling Fan" internal blades, attached to a pre-filled with rubber magnet magnetism of. Surrounds the silicon steel sheet, part of the winding axis of the coil groups, and a Hall sensor component as a synchronous detection means for controlling a set of circuits, the circuit of the two coils wound around the axis of work rotation. Silicon have different poles, the poles and rubber suction magnet repulsion. When "Waterproof Cooling Fan" suck repulsion of static friction is greater than the lice fan when the natural rotation of the blades. Since the Hall sensor assembly provides a synchronization signal, the blade was able to continue to operate, as its running direction, to follow Fleming right-hand rule decision.