Product Description:

The PMB31D-00201-01 is a brushless servomotor produced by Pacific Scientific and supplied within the PMB Brushless Servomotors series. Designed as a rotary actuator for closed-loop motion systems, the unit converts electrical power into controlled torque and speed for indexing tables, packaging axes, and pick-and-place modules. It integrates with digital drives in factory automation lines that require repeatable positioning accuracy and quick acceleration while minimizing maintenance associated with brushed designs. Its brushless design also reduces commutator wear and supports stable performance during repeated start-stop duty.

Mechanically, the motor occupies the footprint of a NEMA Size 34 frame, allowing installation where standardized 3.4-inch mounting patterns are already present. Under a 240 VAC supply, its windings draw a nominal stall current of 5.4 ARMS, which is used by drive sizing software to estimate continuous torque limits and thermal load. Power and feedback leave the housing through flying leads with MS connectors, so wiring can be routed through cable chains without an added terminal box. Rotor position is commutated by a Hall sensor that delivers three logic-level signals to the controller for six-step switching and basic velocity estimation. This feedback arrangement supports electronic commutation and gives the drive a simple reference for rotor orientation during acceleration. Output torque is transmitted through a flat on the stainless-steel shaft, simplifying rigid coupling to gears or pulleys without relying on keyed hubs.

A shaft seal guards the front bearing against splash or dust when the motor is mounted in washdown areas. The motor uses a stack length multiple 1 configuration, so the active core is the shortest available for this frame and helps keep rotor inertia low during rapid reversals. The shorter active section reduces moving mass at the shaft, which can improve response in systems that change direction often. Sealing at the shaft entrance also helps keep contamination away from the bearing cavity during normal machine cleaning.