ABB BSM50N-133AX BSM N-series AC brushless servo motors

The BSM50N-133AX is a compact, low-inertia, high-performance servo motor designed for applications where space is limited and high dynamic response is critical. It represents a step down in physical size and power from the 63mm frame motors.

Decoding the Model Number

• BSM: Brushless Servo Motor

• 50: Frame Size (50mm) - This is the most significant difference.

• N: N-series

• 133: Motor-specific code related to its magnetic stack length and torque output.

• A: Design variant (winding type).

• X: Typically indicates a keyway on the shaft and IP65 sealing.

Key Technical Specifications (Typical)

• Frame Size: 50 mm

• Shaft: Likely a 11 mm or 14 mm diameter shaft with a keyway (confirm with datasheet).

• Feedback Device: High-resolution encoder, standard for the N-series (e.g., 20-bit or 24-bit multi-turn).

• Protection Class: IP65 (Dust-tight and protected against water jets).

• Cooling Method: Natural convection (self-cooled).

Performance Data (Estimated - Must verify with datasheet)

Being a 50mm frame motor, its torque and current ratings are lower than the 63mm models.

• Peak Torque (M₀): Likely in the range of 1.5 - 2.2 Nm

• Rated Torque (Mₙ): Likely in the range of 0.7 - 1.1 Nm

• Peak Current (I₀): Typically around 4 - 6 A

• Rated Current (Iₙ): Typically around 1.5 - 2.5 A

• Rated Speed: 3000 rpm

• Maximum Speed: 5000 - 6000 rpm

• Rotor Inertia: Very low, which is a key feature of this frame size.