Product Description:

The PMB31B-00216-02 is a brushless servomotor produced by Pacific Scientific within the PMB Brushless Servomotors series. It converts drive current into regulated torque and speed for pick-and-place modules, indexing tables, and similar closed-loop axes in industrial automation. The frameless rotor-stator design works with external servo drives and delivers rapid acceleration and controlled deceleration where compact, high-response rotary motion is needed. It is well suited to applications that require frequent starts, stops, and direction changes during repeated motion cycles.

The frame follows the industry-standard NEMA Size 34, allowing installation on existing 4-bolt face mounts. Power and feedback leave the housing through flying leads with MS connectors, which simplifies panel routing by eliminating fixed plugs. At the rated bus voltage, the winding draws a nominal stall current of 2.7 ARMS, which is the continuous phase load the drive must source while the rotor is locked. The insulation system tolerates up to 240 VAC without breakdown. Rotor position is measured at 4096 ppr, so each revolution is divided into 4096 pulses, allowing responsive velocity loops and positioning accuracy well below one degree.

A PTC Thermistor embedded in the stator signals the servo drive when winding temperature nears its limit, allowing an orderly shutdown instead of an abrupt fault trip. The motion transducer is a digital encoder with commutation, providing incremental counts and the phase references needed for closed-loop control at startup. A flat shaft end supports clamp or adhesive couplings and helps prevent torque slippage. The stack length multiple is 1, which corresponds to a single lamination stack and helps keep rotor inertia low for fast indexing cycles. It also keeps the overall motor mass suitable for lightweight gantry or robotic joints.