FEETECH SM120BL Servo Motor

The SM120BL is a high-torque 24V 120kg.cm serial control RS485 servo built with an aerospace-grade Aluminum 7075 case, steel gears (gear ratio 232:1), a steel horn, and 2 ball bearings. Powered by a brushless motor, this no-limit servo operates at 24V, delivering a peak stall torque of 120kg.cm, a rated load of ≤32kg.cm, and a no-load speed of 0.2sec/60° (50RPM), with a stall current of 4A and a rated current of ≤1A. Characterized by a 2.8Ω terminal resistance and a KM constant of 30kg.cm/A, it communicates via digital packets using half-duplex asynchronous serial communication, supporting an ID range of 0–253 and communication speeds from 38400bps to 1Mbps. It offers a 360° running degree (0–4096 steps), backed by a 12-bit magnetic coding position sensor for real-time feedback on load, position, speed, input voltage, current, and temperature. This servo measures 78mm × 43mm × 65.5mm, weighs 485g, and is equipped with a spline OD10mm horn gear and a 300mm±5mm connector wire.

Common use cases: Heavy-duty industrial robot arm and hip joints requiring 120kg.cm torque with RS485 bus communication, large-scale humanoid robot load-bearing joints, heavy industrial automation end-effectors, exoskeleton actuators, and applications demanding high torque with 12-bit magnetic encoder accuracy and brushless motor durability in an aerospace-grade 7075 aluminum housing.