Product Description:

The PMB33F-20214-02 is a brushless servomotor produced by Pacific Scientific for the PMB Brushless Servomotors series. It delivers commanded torque and velocity for positioning tables, feeders, and other motion axes where rapid response and repeatability are required. In these roles, the motor operates as part of a closed-loop drive system, accepting current from a compatible amplifier and sending digital feedback to maintain precise shaft angle. This feedback loop helps the amplifier correct speed and position errors as load conditions change during operation.

A frame rating of NEMA size 34 sets the flange and pilot dimensions so the motor fits standard NEMA-34 mounting patterns. Under worst-case stall at 240 VAC, the winding draws a nominal 11.0 ARMS, so the selected drive must supply that current continuously without derating. Position data are created by an optical encoder that yields 2048 ppr, while commutation tracks on the same disc support sinusoidal phase energization from the drive. The sensing assembly uses a digital encoder with commutation, giving both incremental counts and commutation information in one package. Power and feedback leave the housing through flying leads with MS connectors, which removes the need for a terminal box and simplifies cable routing. Thermal protection is supplied by an embedded PTC thermistor; its rising resistance signals the drive to cut current before the winding insulation is overstressed.

Mechanical coupling is handled by a square key on the shaft, allowing slip-free transmission of rated torque into pulleys or couplings commonly used on industrial equipment. The rotor has a stack length multiple of 3, giving more magnetic volume than shorter versions in the same diameter and supporting higher continuous torque. This longer rotor also suits repeated indexing duty, where quick starts, short moves, and accurate stopping are required. The added active length helps the motor hold torque more consistently during long operating cycles.