Product Description:

The PMB31D-20101-00 is a brushless servomotor built by Pacific Scientific and supplied within the PMB Brushless Servomotors series. As a permanent-magnet rotary actuator, it converts commanded current into controlled torque for closed-loop positioning and speed regulation in assembly robots, pick-and-place heads, and other motion axes on automated lines. The motor integrates with matching drives through low-voltage feedback and power leads, providing a compact source of continuous rotary power where high response and repeatability are required. Because it uses electronic commutation instead of brushes, it supports repeated start-stop duty without brush wear.

Its frame is sized at NEMA Size 34, so the mounting face and pilot dimensions follow the standard 3.4-inch square pattern used on common machine interfaces. When energized from 240 VAC drives, the winding can sustain a nominal stall current of 5.4 ARMS, which marks the thermal limit for continuous holding torque without overheating. Rotor position is detected by an internal Hall sensor, which provides 120-electrical-degree commutation signals to the drive for trapezoidal control. This feedback arrangement gives the drive the rotor sector information needed to switch the motor phases in the proper sequence. Power is routed through flying leads with AMP connectors, allowing direct cabinet wiring without a mating receptacle on the housing. Output torque is transferred through a square key on the shaft, which helps keep pulleys or couplings from slipping during acceleration shocks.

This unit is identified as a standard motor, indicating that it has no application-specific winding or flange alterations. A stack length multiple of 1 indicates the shortest magnetic core in the family, which helps keep inertia low for rapid index moves and quick reversals. The model is also identified as a PMB Series brushless servomotor, so compatible drives can apply the correct commutation table and current limits during operation. The shorter magnetic stack also helps the motor respond quickly in applications that require frequent changes in speed or direction.