Smaller and lighter alternative to AC motors

For engineers looking beyond an AC motor, without the need for a high-spec servo drive, a new offering from STOBER might be worth checking out

The LeanMotor is billed as a highly efficient and compact electric drive that is significantly lighter and smaller than an asynchronous drive. “With the same output as a more expensive Servo drive, this makes the new LeanMotor a robust and cost effective option for those looking for higher performance at a lower cost,” states STOBER

“More rugged than a synchronous motor and delivering better performance than an asynchronous motor, it exceeds the IE4 efficiency level in its respective performance group. Its fan-less construction, with integral holding brake, means it is smaller than comparable drives and with a single power connection; very easy to fit.”

Its robust construction means the LeanMotor can be used for dynamic automation tasks in harsh production environments. It also allows for variable regulation of speed and torque from a standstill to maximum speed with full torque control, without the need for positional sensor elements. And being small and light, engineers can design more compact machines, while users benefit from lower energy consumption and long service life, says STOBER

Cost-efficiency increased by 30%

“Specification of the LeanMotor also means the need to use heavier and larger asynchronous motors is eliminated, with the smaller size and lower weight combination providing around 30% improvement in cost-efficiency, when compared to conventional Servo systems,” adds STOBER. “Additionally, it can regulate more dynamically and efficiently, when compared to an asynchronous motor with incremental encoder, thanks to its greatly reduced flywheel mass.”

Combined with the STOBER SC6 or SI6 drive controllers, the LeanMotor allows for variable regulation of speed and torque, from standstill to maximum speed, without position sensors. Speed and positional accuracy is ± one degree. 

Reduced commissioning and maintenance costs

Benefits flagged up for engineers and designers are that smaller drives can be designed, commissioning and maintenance costs are reduced, and that this new drive can be integrated with a wide range of STOBER gear units and accessories, such as a rugged spring-loaded holding brake. This provides high braking performance throughout the entire service life, concludes STOBER. It is also well suited to automation applications that are exposed to high vibrations and oscillations.

Applications include all types of automation and precision positioning, including manufacturing, packaging, paper, converting and pump drives.


The STOBER LeanMotor is positioned as a smaller, lighter and more robust replacement for AC Motors.
The STOBER LeanMotor is positioned as a smaller, lighter and more robust replacement for AC Motors.

STOBER Drives Ltd

Centrix House
Upper Keys Business Village, Keys Park Road
WS12 2HA

+44 (0)1543 458 858

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