Product Description:

The DKR04.1-W400N-BA35-01-FW is a digital intelligent AC drive controller built by Bosch Rexroth Indramat for the DKR Drive Controllers series. Designed to control three-phase servo and spindle motors on large machinery, the unit converts fixed mains power into a variable DC bus and a pulse-width-modulated output suited for high-power axes. In automated lines, it supports closed-loop velocity and torque regulation for coordinated motion and rapid positioning of heavy loads.

At a switching frequency of 4 kHz, the drive can supply 210 A of continuous output, which corresponds to a sustained mechanical power of approximately 93 kW for connected motors with matching ratings. Logic and relay circuits are energized from a separate AC 230 V ±10% control supply, which helps keep command electronics stable when the main link is de-energized. The power stage accepts mains in the range of 3x AC 400–480 V ±10%, allowing installation on standard factory feeders without an input transformer. Thermal energy from the IGBTs and rectifier is removed by a sealed duct with built-in air blower cooling, so the drive does not depend on separate cabinet fans to maintain the 4 kHz carrier. The design does not include a brake chopper, so excess kinetic energy must be returned to the mains or absorbed by mechanical damping.

For short transients, the output can climb to 282 A, providing additional acceleration capacity for axes with high inertia before current limiting intervenes. During full-load operation, the converter releases up to 2500 W of heat, which is useful when sizing enclosure ventilation and ambient temperature limits. The assembly weighs 150 kg, so the mounting structure must support a substantial static load. System integration is handled through an analog interface that carries velocity or torque setpoints, while return signals are processed from digital servo or resolver feedback channels for fast closed-loop correction. The device is part of line 04, design version 1, and function module version 01.