Product Description:

The 8MSA4X.R0-B5 synchronous motor is produced by B&R Automation as part of the 8MS Three Phase Synchronous Motors series. It is intended to supply continuous rotary motion and precise position control in automated machinery such as packaging axes, pick-and-place heads, and indexing tables. Operating from a three-phase supply, the unit converts electrical energy into mechanical torque that can be regulated by a servo drive through resolver feedback.

At a rated speed of 3000 rpm, the rotor delivers a relative rated torque classed as extra large, giving the motor added capacity for high-inertia loads without upsizing the frame. Heat is removed through a self-cooling design that relies on internal airflow rather than external blowers, so additional cooling hardware is not required. Power and feedback cables leave on side B, which simplifies routing when the motor is mounted with its flange toward the machine frame. A keyed shaft end transmits torque through standard hub components. The size 4 stator diameter and the X length combination balance torque density and overall mass. Because the motor is supplied without a holding brake and without an oil seal, braking or sealing functions must be provided by external elements where required.

Position and speed are monitored by a resolver installed at the non-drive end. The motor uses the BRX resolver variant, with a non-linearity of ±1 angular minute and an absolute accuracy window of ±10 angular minutes. These values allow the servo controller to detect small deviations in rotor angle and adjust current vectors with minimal delay. Combined with the motor’s high torque classification, this feedback arrangement supports smooth low-speed motion as well as rapid accelerations. The absence of a holding brake means mechanical clamps or drive torque must hold loads during power-off conditions.