Types of fans

The types of fans used in our daily lives can be categorized based on their power source into "AC fans," which operate on alternating current, and "DC fans," which operate on direct current. Additionally, based on their shape and airflow mechanism, there are axial fans, blowers, and centrifugal fans.

SANYO DENKI offers a wide range of fan models, each designed for different uses. Let’s take a closer look at the differences between them.

Fan types: Differences by power source

First, there is the difference in the power source that drives the fans. There are two types: AC fans, which use power from a wall outlet, and DC fans, which run on direct current. AC fans spin at a fixed speed based on the power supply’s frequency, while DC fans can adjust their speed using a motor and control circuit.
Nowadays, DC fans are widely used due to their ease of control and variety of models. There are also ACDC fans, which convert AC power into DC and operate like DC fans, even when plugged into a regular outlet.

Fan types: Differences by Shape

The most commonly used type is the axial fan.
It has blades mounted at the center of a frame and pulls air in from the front, and expelling it to the rear. This is probably the kind of fan most people imagine when they hear the word “fan.” Axial fans are widely used because they offer high airflow and tend to operate quietly.
There are several variations of axial fans to suit different needs. "Counter Rotating Fan" which are made up of two axial fans arranged front to back, with the blades rotating in alternate directions to improve the straightness of the airflow and generate high static pressure; "Endurance Fans," which can be used under harsh environments or with extremely high or low temperatures; and "Reversible Flow Fan," which can blow air in both directions by reversing the rotation direction of the blades.

Unlike axial fans, "Blowers" and "Centrifugal fans" redirect airflow by 90 degrees—from inlet to outlet—rather than pushing air straight backward.
These fans are especially useful in devices where space limitations prevent air from being discharged directly behind the unit. Blowers are ideal for spot cooling and for equipment with densely packed components, because of their ability to generate high static pressure. Centrifugal fans are also useful for extracting air from tightly enclosed equipment. We'll explain the features of each fan type in more detail later.

* Fans are marked with symbols indicating the airflow direction and the rotation direction of the blades.
Before installation, please check these symbols to confirm the airflow direction. Also, make sure the fan is suitable for your equipment by carefully reviewing its specifications and requirements.
​

Supervised by: SANYO DENKI CO., LTD. Cooling System Design Department

Update date: 2022-03-18 00:00 /release date: 2018-01-16 00:00