Product Description:

The M-203-A-31 is a brushless servo motor produced by Kollmorgen within the M Goldline Servo Motors series. Designed for precision motion tasks, the unit converts drive commands into tightly regulated torque and speed, making it suitable for indexing tables, electronic cams, and light material-handling axes. A compact stator and low-loss windings give it the thermal capacity needed for continuous duty in automation cells. The flange mounts directly to gearheads or load couplings, while resolver or encoder options from the series provide the position feedback required by modern digital amplifiers.

Electrical behavior includes a back electromotive force of 79.5 Vrms/kRPM, which helps size the drive’s DC bus and commutation settings. During constant load, the motor produces 2.25 N-m of stall torque while drawing only 1.70 Arms, a combination that supports low-current amplifiers and minimizes cable heating. The coil inductance is 185.0 mH, which smooths current ripple, and the copper path has 17.7 Ω of DC resistance, which limits inrush at startup. A motor constant of 0.272 N-m/W supports predictable thermal output, and a housing-to-ambient thermal resistance of 1.0 °C/W helps estimate heat dissipation requirements. The rotor has four poles, which sets the electrical frequency in relation to speed.

For short acceleration periods, the motor can deliver a peak torque of 7.45 N-m when the amplifier supplies up to 6.0 Arms per phase. The rotor’s reflected inertia is only 0.000836 kg-m², which supports rapid reversals without overloading the drive. The winding mass heats gradually because the thermal time constant is 18 min. Continuous output reaches 0.60 kW, and that rating is achieved at 2500 rpm, which is also the motor’s maximum operating speed. Operation is permitted up to 250 Vrms line-to-line, matching common industrial supply modules.