PMB31B-20201-02 Pacific Scientific
Wake Industrial LLC is not an authorized distributor of this product.
Wake Industrial LLC is not an authorized distributor of this product.
The Pacific Scientific PMB31B-20201-02 is a NEMA Size 34 brushless servomotor with a square key shaft design and hall sensor. As part of the PMB Brushless Servomotors series, it features flying leads with MS connectors and a PTC thermistor for customization. The motor has a nominal stall current of 2.7 ARMS at 240Vac maximum.
Internal Product Review
The PMB31B-20201-02 is a Pacific Scientific PMB Series brushless servomotor built with a NEMA Size 34 frame and a square key shaft design. Flying leads with MS connectors and Hall sensor feedback support straightforward integration and dependable commutation in motion-control assemblies. A PTC thermistor and 2.7 ARMS nominal stall current make this unit a well-balanced choice for thermally monitored servo duty.
Have a part to sell?
Wake Industrial Warranty
To contact sales for pricing and lead time:
Payment Methods
Shipping Methods
Our Credentials
Product Description:
The PMB31B-20201-02 is a brushless servomotor manufactured by Pacific Scientific and positioned inside the PMB Brushless Servomotors series. The device serves as the active drive element in numerically controlled machinery, converting inverter current into precise shaft torque for applications such as light material handling, indexing stations, and small packaging lines. Within a motion system, it works with an external drive to regulate speed, position, and acceleration, allowing the machine controller to command rapid moves, settle quickly, and hold the axis without mechanical drift. This arrangement makes the motor suitable for compact automation axes that require repeatable motion and stable response during frequent starts and stops.
Its mechanical envelope follows the NEMA Size 34 frame, so the flange and pilot diameters align with standard U.S. mounting interfaces. Continuous electromagnetic loading is indicated by a nominal stall current of 2.7 ARMS, and that value applies with a supply line of 240 Vac, giving a clear reference for inverter matching and conductor sizing. Rotor position feedback is produced by a Hall sensor, enabling six-step commutation when paired with the drive controller. The stator laminate stack uses a stack length multiple of 1, which keeps the motor compact and supports responsive acceleration in lighter-duty servo applications.
For electrical terminations, the motor is supplied with flying leads that terminate in mating MS connectors, allowing the unit to be disconnected without reworking the full cable path. Overtemperature protection is handled by an embedded PTC thermistor whose rising resistance alerts the drive before insulation limits are exceeded. Mechanical power is transferred through a shaft machined with a square key, a profile that mates with keyed couplings to help prevent slip during repeated start-stop cycles. These features support straightforward integration, dependable commutation feedback, and thermal monitoring during prolonged operation.
