Product Description:

The PMB31B-20116-00 is a brushless AC servomotor produced by Pacific Scientific within the PMB Brushless Servomotors series. In automated machinery, it supplies closed-loop rotary motion for axes that need fast acceleration and position repeatability, such as pick-and-place heads, indexing tables, and light machine tools. The unit is a standard motor, so it uses the base electrical and mechanical options of the series without customer-specific changes.

Its frame corresponds to the NEMA Size 34 classification, meaning the front face measures 3.4 inches and the mounting holes follow that standard. Position feedback is supplied by an integrated encoder that delivers 4096 ppr, so the drive receives 4096 discrete pulses per revolution for high-resolution control. Under maximum 240 V AC bus conditions, the motor can draw a nominal stall current of 2.7 ARMS, which is the continuous current the drive must supply when the shaft is locked. A square key on the output shaft transmits torque without slipping and keeps pulleys or couplings in a fixed orientation. The built-in digital encoder with commutation provides both incremental position data and phase-aligned commutation signals, allowing the drive to energize the stator correctly from startup without separate Hall sensors.

Electrical connection is supplied through flying leads with AMP connectors, so the cable harness can be routed directly to the drive cabinet without a detachable motor plug. Magnetic stack depth is identified by a stack length multiple of 1, the shortest lamination pack offered for this frame, so inertia and continuous power are suited to light loads with rapid reversals. The motor can be matched with Pacific Scientific S-class amplifiers, and its wiring style stays consistent with that platform in multi-axis installations.