Product Description:

The B-204-C-21 brushless servo motor is produced by Kollmorgen and belongs to the Goldline B and BH Motors series. It is intended for precision motion axes where a drive must translate electrical energy into tightly regulated rotary output for packaging machines, pick-and-place heads, or coordinated CNC stations. By pairing a compact frame with four magnetic poles, the motor supports fast response while maintaining consistent torque for industrial automation routines that need repeatable positioning.

During continuous operation, the unit delivers 4.79 N-m of stall torque while drawing a maximum of 9.8 Arms. A thermal resistance of 0.68 °C/W helps the windings remain within limits at the rated load. A torque constant of 0.49 N-m/Arms links the line current to shaft torque, and the back electromotive force constant of 29.6 Vrms/kRPM indicates the voltage generated when the shaft is driven externally. With 12 mH of inductance and 0.786 Ω DC resistance, the electrical time constant supports stable current loops in modern PWM drives. The motor is rated for 2.8 kW of output at its rated speed, and static friction of 0.10 N-m helps limit dead band when reversing direction.

For short duty peaks, the current can rise to 29.5 Arms, producing a corresponding shaft torque of 13.7 N-m without loss of synchronism. A rotor inertia of 0.0001729 kg-m² allows quick acceleration yet limits overshoot when the drive issues rapid deceleration commands. Thermal soak is moderated by a 20 min thermal time constant, giving the system time to disperse heat during intermittent overloads. The assembly weighs 6.2 kg, which is light enough for moving-axis mounting while still providing mechanical rigidity. This operating range supports intermittent overloads and frequent speed changes in automated motion systems.