Optimised, gearbox-less variable speed fan control, previously developed for cooling tower fans, has now been extended to higher power ratings.

Developer Baldor says they can handle very large applications, including those in power generation and the heavy processing industries.
The company also makes the point that, by eliminating the right-angled coupling used on conventional drives, other benefits include energy savings, improved reliability and much quieter running.
It also claims that a novel permanent magnet-based motor further increases energy efficiency and reduces size of the motor, allowing it to sit underneath the fan in the space usually required for the gearbox.
Maximum torque is now up to 13,500Nm, with 26 rating choices, spanning from 7.5kW at 500rpm base speed to 187kW at 130rpm base speed.
The motor flange footprint is designed to interchange with standard gear reducers, but adding a foot mounting adapter plate provides a simple means of fitting the motor in other gearbox footprints.