"Waterproof Cooling Fan" uses digital brush less DC external rotor motor centrifugal fan. Or, using a centrifugal fan EC motor. EC (Electrical Commutation) electrical power to DC power, built-in DC to AC (invert module through six), using the rotor position feedback, three-phase AC, permanent magnet synchronous motors. "Waterproof Cooling Fan" DC brush less motor is power quality and appearance rather than the substance of the motor, EC motor is essentially a three-phase AC permanent magnet synchronous motor) EC motor is a built-in intelligent control module DC brush less maintenance-free motor, comes with RS485 output interface, 0-10V sensor outputs, 4-20mA speed control switch output interface, output interface and main alarm signal output from the interface. "Waterproof Cooling Fan" with high intelligence, high energy, high efficiency, long life, low vibration, low noise, and other characteristics can work uninterrupted.