Permanent Magnet Direct Drive Fan Motor
OVERVIEW Direct drive permanent magnet motors are a newer technology available on most Marley NC Cooling Towers. The permanent magnet motor directly drives the fan, eliminating a number of components, including the gear drive, driveshaft, pillow block bearings and couplings, and associated installation and alignment costs. Compared to other power transmission technologies, direct drive motors can have significantly higher initial costs. However, customers can realize substantial savings on annual energy and maintenance costs.


In some cooling tower applications, direct drives are capable of achieving a one-to-two percent efficiency advantage compared to gear drive systems. Efficiency can also be equal to or less than a gear drive system due to NEMA premium motor efficiency levels mandated by the U.S. federal government. To meet the torque requirements for cooling towers, permanent magnet motors become heavier and taller than standard induction motors. Maintenance professionals must possess knowledge of permanent magnet technology due to its potential to generate electricity even when the power is shut off. A VFD is required to control speed and conserve energy.


Genuine Marley OEM parts are precision-engineered to provide you with a reliable product. While other suppliers may offer parts at an initial savings, you risk lowering performance — and losing FM and CTI ratings. Marley OEM parts provide the durability you can trust because we design and manufacture them exclusively for cooling towers.

With plant operation relying on your cooling tower performance, it’s important to select the parts that are among the highest quality available — Marley OEM parts.

  • Available on most Marley NC towers

  • Minimal maintenance

  • VFD required


Marley Cooling Tower Parts