Product Description:

Kollmorgen’s CR03251 is a digital servo amplifier from the Servostar CD Drives series. As a compact drive model, it regulates torque, velocity, and position for brushless motors in automated machinery. The unit rectifies single-phase mains power, stores energy on an internal DC link, and modulates that power through high-frequency switches. Its role in industrial automation is to link a motion controller to the motor, delivering current that accurately follows commands while supervising voltage and thermal limits.

The drive is supplied from a nominal 230 VAC utility line and converts that input to an internal link voltage of 325 VDC. Under continuous duty, it delivers 3 A of RMS output current while tolerating surges up to 9 A RMS for rapid acceleration. Excess energy is limited by an overvoltage threshold of 430 VDC, and a loss of mains power is detected when the link falls to 90 VDC. At these limits, the controller initiates a safe shutdown to protect its semiconductors and the connected equipment. Average heat dissipation is 60 W, so cabinet airflow must remove the resulting thermal load to maintain component life. The power switches operate at a high carrier frequency that keeps audible noise low and reduces current ripple in the motor.

Control precision is supported by several high-speed loops. The current regulator refreshes every 62.5 µs, the velocity algorithm refreshes every 250 µs, and the position calculator refreshes every 500 µs, permitting tight servo stiffness even with lightly coupled loads. Pulse-width modulation occurs at 16 kHz and coordinates with these control loops to minimize torque ripple. Command data enter through a SERCOS interface that transmits frames at a 2 ms rate, matching the drive’s internal scheduler. Rotor position is sensed with a resolver energized at 4.25 VAC, providing shaft-angle feedback that resists electrical noise. These feedback and control functions support precise motion in automated equipment without requiring additional panel depth.