Product Description:

The PMB31B-00201-03 is a brushless servomotor produced by Pacific Scientific in the PMB Brushless Servomotors series. Designed for closed-loop industrial automation, the unit converts electrical power into regulated rotary motion for positioning tables, pick-and-place heads, and similar machinery. Its standardized frame format allows direct mounting to common gearboxes and brackets without custom adapters in many machine layouts. This format is useful on compact servo axes that need precise starts, stops, and reversals during repetitive production cycles, and the brushless design supports long operating life with reduced wear.

The motor uses NEMA Size 34, which sets the flange and pilot dimensions for compatibility with standardized mounting hardware. Electrical hookup is provided through flying leads with MS connectors, allowing quick mate-and-lock installation while preserving the factory-terminated cable assembly. On a 240 VAC bus, the winding draws a nominal stall current of 2.7 ARMS, which is useful when matching the motor to a compatible drive and setting current limits. Rotor position feedback relies on an internal Hall sensor, enabling six-step commutation without an external encoder. Motion is delivered through a flat shaft end, which works with clamp or set-screw hubs and supports straightforward coupling on compact drive axes.

A factory kit adds shaft seal and PTC thermistor protection. The shaft seal helps limit ingress at the output end, while the thermistor monitors winding temperature so the control system can respond to rising heat. The motor uses a stack length multiple of 1, giving it the shortest active core in this configuration where rated torque is sufficient and low inertia is preferred. The shorter magnetic stack can help reduce rotor inertia, which is useful on applications that emphasize responsive acceleration and deceleration rather than maximum continuous torque.