Direct Drive Versus Belt Driven Fans

It s a motor connected to your fan in one of only two ways.

Direct drive versus belt driven fans.

Direct drive fans have no power transmission loss since the propeller is directly connected to the motor shaft. More often than not the maintenance cost of this kind of fan is also comparatively lower. In the former the motor connects to the fan wheel with nothing in between. The second pulley is connected to a shaft that drives the fan propeller.

In a direct drive configuration the fan motor that controls the movement of the fan blades is connected either to a shaft or fan axle. In the later there is a belt sometimes more than one connecting the motor to move the fan. Belt drive fans have two additional bearings. Direct drive or belt drive.

The two bearings on direct drive fan motors which are 7 horsepower and larger are typically regreaseable. On both direct drive and belt drive fans the motor has two bearings. With the growing acceptance and affordability of vfd motor controllers direct drive fans are increasingly finding their way into mainstream industrial fan applications. Unlike belt driven fans there s less energy loss because there s a reduced amount of friction as the fan operates.

On a direct drive fan as implied by the name the fan propeller is connected directly to the shaft of the motor. Where on a belt drive fan the fan motor shaft has a pulley connected by a belt to a second pulley. Thus the fan blades will rotate at the same speed as the motor rotates. Unlike the belt driven fans in case of a direct drive fan there is lesser energy loss.

This is because of the fact that the amount of friction is greatly reduced in case of this fan when the fan is operating. Direct drive fans should be designed for acceptable bearing life.