Fan Builder Seeks Ideal Motor

Aug. 1, 2011
In San Bernardino, Calif., industrial fan manufacturer MacroAir Technologies continues to refine its unique air circulation products for better efficiency.

Its six-blade industrial fan outperforms its 10-blade fan series while requiring 40 percent less aluminum and 13 percent less power in its manufacture. MacroAir ( has also managed to lower shipping costs by reducing weight by 30 percent.

Such innovation comes from MacroAir’s design engineers, who have to research and spec the right components. Engineer Jeff Johnson says the right component is one that “allows us to design and build a product with optimum performance and extended life.”

The gearmotors specified by MacroAir engineers for their HVLS fans are the GST 05 and GST 06 from Lenze Americas ( They also use a range of inverters, including the Lenze-AC Tech SM/SF Series. For the future, they are considering the SMV Nema 4X inverters. These enclosed inverters can be mounted with the fan on the ceiling or directly on the wall; they don’t require another enclosure and are a good match for washdown applications.

Regarding the Lenze GST gearmotors, Johnson says he likes “the quality of the gears, made from case-hardened steel, and the fact that they are helical as opposed to spur. Helical gearing has the gear teeth cut at an angle in relation to the axis of rotation, as opposed to a spur gear where the teeth are parallel to the axis of rotation. The advantage to a helical is that there is more tooth contact and more of a ‘rolling’ effect as the gears mesh. With more contact, there is more torque and the ‘rolling’ effect cuts down on the gear noise.”

Lenze Americas ( 

MacroAir (

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