Product Description:

The PMB31B-00214-03 is a brushless servomotor produced by Pacific Scientific as part of the PMB Brushless Servomotors series. Designed for closed-loop control, the unit converts electrical command signals into repeatable rotary motion for pick-and-place axes, indexing tables, and small gantry heads used in automated assembly lines. It incorporates an embedded encoder so the drive can monitor rotor angle and maintain precise commutation throughout continuous duty cycles. That feedback also helps the axis maintain stable motion during start-up, low-speed travel, and repeated positioning moves.

Mechanical interfaces follow the NEMA Size 34 frame, giving the motor a 3.4-inch square mounting face that fits standard servo gearboxes and brackets. Under a 240 VAC drive, the winding reaches a nominal stall current of 2.7 ARMS, which marks the continuous torque point where additional cooling is not required. Feedback is supplied by a 2048 ppr incremental encoder, delivering high-resolution position data for fine velocity trimming. Power and signal conductors exit the housing as flying leads with MS connectors, which simplifies field wiring because no separate pigtail harnesses are required. Commutation data is provided by a digital encoder with commutation tracks, allowing the drive to align phase currents without separate Hall sensors.

The motor includes Shaft Seal and PTC Thermistor, so it resists splash ingress while the thermistor reports winding temperature for drive-side protection. Torque is transferred through a flat shaft, which eases coupling to pinch rollers and hub clamps without keys. Magnetic length uses Stack Length Multiple 1, which is the shortest lamination stack available in this frame and gives the rotor lower inertia for rapid acceleration. The sealed shaft end also helps protect internal bearing areas where light splash or airborne contamination may be present. The shorter stack helps the motor respond quickly in applications that favor fast indexing and frequent speed changes.