Product Description:

The PMB31B-00214-01 is a brushless servomotor built by Pacific Scientific for the PMB Brushless Servomotors series. It is a permanently excited motor intended for closed-loop drive systems. In service, it converts electrical energy into controlled shaft torque and speed for packaging stations, pick-and-place units, and light machine tools. Its brushless design supports accurate positioning and repeatable motion during rapid starts, stops, and speed changes.

With a frame coded as NEMA size 34, the motor occupies a 3.4-inch square mounting footprint that matches many legacy stepper installations and eases integration on existing mounting patterns. During locked-rotor testing at 240 VAC, the winding draws a nominal stall current of 2.7 ARMS, which is used to size the amplifier’s continuous current rating. Rotor position is captured by an optical feedback device that delivers 2048 ppr, supporting fine velocity loops and precise positioning. The feedback element is a digital encoder with commutation, so drive currents stay synchronized without separate Hall sensors. A machined shaft flat on the output shaft provides a positive interface for couplings or pulleys and helps keep rotor inertia low for fast acceleration.

Power and feedback exit the housing through flying leads with MS connectors, which allows cable routing through tight spaces before final connection. This connection style keeps the motor body compact and avoids a large fixed terminal housing at the rear. The motor has a factory-installed shaft seal that helps guard the front bearing against coolant mist or fine dust. The Stack Length Multiple of 1 corresponds to the shortest lamination stack in the series, favoring a compact package where installation space is limited. The shorter stack also reduces overall motor length, which can help on axes with limited mounting depth.