Product Description:

The PMB31B-00201-01 is a brushless servo motor produced by Pacific Scientific and assigned to the PMB Brushless Servomotors series. The unit converts drive current into controlled rotary motion for positioning, tensioning, or speed-regulated axes in automated machinery. Its brushless architecture reduces maintenance, while the internal magnetics are optimized for closed-loop operation through commutation feedback. This type of motor is commonly used where smooth speed control and repeatable positioning are required from a compact rotary actuator.

With a NEMA Size 34 frame, the motor occupies a 3.4-inch square mounting footprint that aligns with common U.S. flange patterns used in industrial equipment. Continuous stall capability is limited by a nominal current draw of 2.7 ARMS at 240 VAC, which helps the amplifier supply the required phase current without thermal overload during continuous operation. Power and feedback conductors exit the housing as flying leads with MS connectors, simplifying cable connection in compact installations. This connection style keeps both power and feedback conductors accessible without a separate terminal housing. Rotor position is detected by an integral Hall sensor, allowing six-step commutation when an encoder is not specified. A flat output shaft provides a positive, slip-free interface with set-screw couplings or pulleys.

For washdown or particulate environments, the available shaft seal option limits ingress at the output journal and helps protect the bearing set. It also helps maintain lubricant integrity around the output journal during regular operation. The stack length code of 1 indicates the shortest lamination column in the series, so inertia and weight are kept low for high-acceleration moves. The shorter body length also reduces the space needed along the shaft axis in tightly packed machine layouts.