In the later there is a belt sometimes more than one connecting the motor to move the fan.
Belt driven vs direct drive fan.
The second pulley is connected to a shaft that drives the fan propeller.
It s a motor connected to your fan in one of only two ways.
Deciding between a direct drive fan and a belt drive fan is fairly straightforward once you know all of your other variables like fan size application space fan speed needs and likely wear and tear in your application.
Since there is at least a 3 percent drive loss for a belt drive fan and no v belt drive loss for a direct drive fan the direct drive fan by default will be more efficient.
In the former the motor connects to the fan wheel with nothing in between.
Direct drive or belt drive.
Note that for shaft driven direct drive fans arr.
7 8 etc the flexible drive coupling loss is immeasurable and ignored so its drive efficiency follows that of an arr.
Direct drive fans have no power transmission loss since the propeller is directly connected to the motor shaft.
This is because of the fact that the amount of friction is greatly reduced in case of this fan when the fan is operating.
In addition belt driven fans are less efficient than a direct driven fan of equivalent size due to transmission losses.
Unlike the belt driven fans in case of a direct drive fan there is lesser energy loss.
On a direct drive fan as implied by the name the fan propeller is connected directly to the shaft of the motor.
Direct drive fans should be designed for acceptable bearing life.
4 direct drive fan.
More often than not the maintenance cost of this kind of fan is also comparatively lower.
The two bearings on direct drive fan motors which are 7 horsepower and larger are typically regreaseable.
Greater efficiency is the biggest pro of direct drive fan configurations.
On both direct drive and belt drive fans the motor has two bearings.
Where on a belt drive fan the fan motor shaft has a pulley connected by a belt to a second pulley.
As energy costs increase it has become desirable to transition to a more efficient means of driving fan systems.
There s also no belt residue and these fans cost less to maintain generally speaking because belts don t wear down and break.