Product Description:

The PMB31D-20114-03 is a brushless servo motor produced by Pacific Scientific within the PMB Brushless Servomotors series. Designed for closed-loop motion platforms, it supplies precise rotary power so automated packaging, dispensing, or material-handling stations can position loads quickly and repeatably. Its compact format suits applications that need accurate speed regulation and repeatable positioning in a small mounting envelope.

Its frame conforms to the NEMA Size 34 standard, giving it a 3.4-inch square face that simplifies interchange with other 34-frame drives. A 2048 ppr incremental encoder mounted on the shaft generates digital feedback pulses, and the high line count lets the controller resolve motion down to fractions of a degree. The feedback device is a digital encoder with commutation, so Hall-level signals for phase sequencing are delivered at the same connector and external wiring is reduced. Under maximum 240 VAC drive conditions, the motor can hold rated torque while drawing 5.4 ARMS of nominal stall current, which is useful when matching the motor to a compatible amplifier. Power and feedback leave the housing through flying leads with AMP connectors, allowing connection without soldering or crimping new lugs.

The motor is factory fitted with a shaft seal and PTC thermistor, combining ingress protection with over-temperature sensing that can trigger a controlled shutdown. Output torque is transferred through a square key machined into the shaft, giving positive drive for couplings or pulleys without relying on friction alone. The motor uses a stack length multiple of 1, which is the shortest lamination stack in the series and helps keep inertia low for fast acceleration in light-load axes. This arrangement supports compact axis layouts where quick response and stable feedback are both important.