Product Description:

The SERVOSTAR CD Light from Kollmorgen is a digital servo drive in the CD Servostar CD Drives series, intended to regulate torque, velocity, and position of brushless servomotors in automated machinery. By interfacing with encoder feedback and high-speed control loops, the unit closes the motor control loop electrically instead of mechanically, enabling precise motion in packaging, electronics assembly, and similar industrial axes. It continuously compares command input with motor feedback so correction signals can be applied during acceleration, steady running, and stopping. This helps the axis respond predictably when load conditions change during normal operation.

Its analog front end samples reference signals with a 12-bit A/D converter, while the command voltage of ±10 VDC provides a symmetric range for bidirectional speed or torque requests. The current loop refreshes every 16 kHz, and the matching maximum PWM frequency lets the power stage reproduce those updates without aliasing. Encoder power is supplied at 250 mA from a regulated 5 V rail, and incremental encoder signals up to 3 MHz can be processed before quadrature decoding. The drive also accepts feedback counts within an analog input window of ±22,500 counts, supports cable lengths up to 50 ft (15 m), uses a PTC input that switches at 12.4 kΩ to protect the motor against thermal overload, and runs its velocity loop at 4 kHz for tighter speed regulation.

The position controller resolves up to 10,000,000 encoder lines per revolution, and its internal logic can be powered from an optional 24 VDC source to keep critical functions active when the main bus is off. Computation bandwidth comes from a 40 MHz processor clock that synchronizes digital filters with a zeroing interval of 32 ms for automatic offset calibration at power-up. Keeping the logic energized during a bus outage supports orderly signal handling and preserves control readiness for the next enable cycle. Automatic offset calibration also helps reduce startup drift so the drive begins operation with a stable internal reference.