BL-MC150J-20SNA-A by Okuma

The BL-MC150J-20SNA-A is a brushless AC servo motor manufactured by Okuma and supplied through the BL Servo Motors series. Designed for industrial automation, it converts commanded electrical energy into precise shaft movement so machine tools can maintain repeatable motion profiles without mechanical backlash. Integrated with a matched drive, the motor coordinates axis travel in multi-axis CNC machining centers and other automated equipment where high dynamic response and accuracy are required. This type of motor is commonly used on feed axes where rapid reversals and smooth interpolation are required.

Its electrical platform uses a rated winding voltage of 133 V, which sets the back-EMF level the drive must counter during speed regulation. When the windings draw 13.4 A of continuous current, the motor operates at its thermal limit while still maintaining normal service life. Under these conditions, the shaft can reach 2000 rpm, aligning with feed rates common in medium-power machine axes. The electromagnetic design yields 3 kW of mechanical output, which reflects the combination of rated torque and speed at nominal efficiency. That output level suits servo axes that need sustained motion rather than only brief peak bursts. An 8-pole rotor lowers electrical frequency requirements, allowing the associated inverter to run cooler and simplifying filter design.

The motor has a continuous torque of 133 kgf·cm, providing stable force for cutting passes or pick cycles without undue heating. During axis lock-in or rapid acceleration, it withstands a stall load of 16.2 N·m, providing headroom before current limiting occurs. Rotor position is resolved by the Type-ER incremental encoder, so the control loop receives high-resolution feedback for micron-level positioning. The encoder signal lets the drive correct position and velocity errors during contouring moves and short index cycles. The motor is assembled in Japan for BL series production.