Product Description:

The B3.SM.000-4200 synchronous servo motor is produced by KEB in the SM Synchronous Servo Motors series. It is intended for closed-loop drive systems where accurate position, velocity, and torque control are required. By converting controlled three-phase electrical energy into rotary motion, the unit forms the mechanical output stage of compact automation equipment, motion modules, and general-purpose industrial axes.

At the motor’s rated operating point, the armature runs at a nominal speed of 4000 rpm while delivering a steady torque of 2.0 Nm. Together, these figures translate into a continuous mechanical output of 830 W. To achieve this, the drive supplies 230 V phase-to-phase and a nominal current of 4.7 A. The internal electromotive force is proportional to speed with a voltage constant of 37.2 V/1000 rpm, a parameter that helps the controller predict back EMF during acceleration. Copper losses are governed by a winding resistance of 1.7 ohms, while energy stored in the magnetic field is indicated by a winding inductance of 5.6 mH. These electrical characteristics help tune the inverter, influence current loop bandwidth, and support safe regenerative braking.

For transient demands, the rotor can generate a peak torque of 11.0 Nm at 4700 rpm when the drive momentarily supplies up to 33.0 A. This overload window lets machinery clear inertial loads before returning to continuous limits. When unloaded, the shaft accelerates to 7200 rpm, confirming adequate margin between nominal and maximum speed. The reflected inertia of just 0.57 kg cm² permits fast reversals without excessive servo gain, and stall ratings of 2.3 Nm and 5.5 A indicate the minimum holding effort during static positioning. Overall weight is 2.9 kg, allowing the motor to be installed on lightweight axes that need rapid dynamic response without sacrificing accuracy.