Product Description:

The KA840JS0 is a servo motor produced by Sanyo Denki for the K SANMOTION Servo Motors series. Designed for machine axes that require precise position and velocity control, the motor converts drive current into rotational motion that can be tightly regulated by a digital amplifier. In automated assembly cells, packaging equipment, and semiconductor-handling stations, this model supplies mid-range power in a compact frame. Its permanent-magnet synchronous design provides the responsive operation needed for repetitive positioning and speed-controlled tasks.

The armature winding has an inductance of 1.5 mH, which helps filter current ripple, and a resistance of 0.95 Ω, which affects copper losses and temperature rise. Rated operation is achieved when the drive supplies 85 V at 5.7 A. Under these conditions, the shaft delivers 400 W of mechanical output at 2500 rpm. The motor produces 1.53 N·m of rated torque at this speed, and its torque constant of 0.31 N·m/A allows the controller to calculate torque from the measured phase current. A mechanical time constant of 4.8 ms indicates that the rotor accelerates quickly after voltage is applied, supporting short indexing movements in pick-and-place equipment and conveyor systems.

The motor can sustain a continuous stall torque of 1.70 N·m, allowing it to hold a stationary load while remaining within its thermal limits. For vertical axes, the integrated brake provides 1.96 N·m of holding torque and draws only 0.11 A, which limits brake power dissipation. Rotor inertia is 5.0 × 10⁻⁴ kg·m² and influences acceleration and deceleration during dynamic motion. The complete motor assembly weighs 4.90 kg, helping limit the load added to a gantry or robotic arm. Its voltage constant is 32.9 × 10⁻³ V per rpm, allowing the drive to use back electromotive force for accurate speed estimation during closed-loop control.