Image Credit: Allied Electronics, Inc. | Digi-Key Corporation | APC by Schneider Electric
Electronic cooling fans move air to cool electronic devices such as computers and appliances. They are also used in telecommunications, military, and general industrial applications as well as in heating, ventilation, and air conditioning (HVAC) systems. Important performance specifications for electronic cooling fans include maximum airflow, maximum static pressure, and maximum sound level. Important electrical specifications to consider include motor voltage, operating current, and power. Several blower and fan type configurations are available. Axial fans move air parallel to the axis of the fan and provide relatively high flow rates and low pressures. By contrast, centrifugal or radial blowers move air perpendicular to the blower axis and provide relatively low flow rates and high pressures. Other available configurations include tube axial fans, vane axial fans, crossover (tangential) blowers, and multistage blowers.
Motor Options and Uses
Electronic cooling fans use several types of motors and bearings. AC motors that operate at 50 to 60 Hz include single, multiphase, universal, servo, induction, and gear motors. Fans and other components that operate at 400 Hz AC are primarily used in aerospace applications. DC motors are commonly used in variable speed and torque applications. Brushless DC motors use internal non-contact sensing devices to activate external commutating electronics. These motors have armature windings on the stator and the field on the rotor. Bearing types include ball or roller, and sleeve or bushing. Ball bearings are used to provide smooth, low friction motion in rotary applications. There are three basic types of ball bearings: radial, angular contact, and thrust. Sleeve bearings or bushings are used to constrain, guide, or reduce friction. These bearings are also called journal or plain bearings.
Important specifications to consider when searching for electronic cooling fans include maximum sound levels; thickness, length, and diameter; casing or enclosure dimension; and operating temperature. Common features or options for electronic cooling fans include locked rotor and over temperature protection, variable speed or flow, and fault detection. Electronic cools fans that feature IC/PCB cooling are designed to cool integrated circuits (ICs) and printed circuit boards (PCBs).