Description

The REXROTH DKC03.3-040-7-FW is a high-performance digital servo drive from Bosch Rexroth’s IndraDrive C series, designed for precise motion control in demanding industrial automation applications. As part of the modular IndraDrive platform, this compact 40 A-rated amplifier delivers robust power to synchronous and asynchronous servo motors—particularly the MSK and MTK motor families—enabling dynamic positioning, speed control, and torque regulation with sub-millisecond response times. The “FW” suffix indicates that the unit ships with a specific, stable firmware version pre-installed, ensuring compatibility with existing IndraMotion control systems and reducing commissioning time.

Engineered for integration into machine tools, packaging lines, robotics, and material handling systems, the REXROTH DKC03.3-040-7-FW supports the Sercos III real-time Ethernet communication protocol, allowing deterministic data exchange with higher-level controllers such as IndraControl L or V PLCs. It features integrated safety functions including Safe Torque Off (STO) per EN 61800-5-2, eliminating the need for external contactors in many safety architectures. With its compact footprint, efficient heat dissipation, and support for DC bus sharing in multi-axis configurations, the REXROTH DKC03.3-040-7-FW optimizes panel space while maximizing energy efficiency and system responsiveness.

Technical Specifications

Main Features and Advantages

High dynamics with intelligent thermal management: The REXROTH DKC03.3-040-7-FW leverages advanced current control algorithms to deliver exceptional bandwidth and tracking accuracy, even under rapidly changing load conditions. Its internal thermal model continuously monitors I²t energy and adjusts performance to prevent overheating—enabling sustained peak operation during acceleration phases without triggering nuisance faults. This makes it ideal for high-cycle applications like pick-and-place robots or flying shear cutters.

Integrated safety and simplified wiring: Unlike older drives requiring external safety relays, the REXROTH DKC03.3-040-7-FW includes dual-channel STO inputs compliant with ISO 13849-1, allowing direct connection to safety PLCs or emergency stop circuits. The built-in 24 VDC brake supply eliminates the need for separate power sources for motor holding brakes—reducing component count and simplifying cabinet layout. All field connections use screw terminals with clear labeling, and the drive supports automatic motor recognition via the Sercos III link.

Firmware-ready for rapid deployment: The “-FW” designation signifies that the REXROTH DKC03.3-040-7-FW arrives with validated firmware optimized for stability and feature completeness—avoiding post-installation updates that could delay production. It is fully supported by Rexroth’s IndraWorks engineering suite, enabling parameter cloning, oscilloscope diagnostics, and auto-tuning directly from the software. Additionally, the drive supports DC bus coupling with other IndraDrive C units, allowing regenerative energy from decelerating axes to be reused by accelerating ones—cutting energy consumption by up to 30% in multi-axis machines.

Application Field

The REXROTH DKC03.3-040-7-FW is extensively used in CNC machining centers and turning lathes, where it powers feed axes and spindle orientation with micron-level precision and minimal jitter. Its fast current loop ensures smooth surface finishes and consistent tool life, even during complex contouring operations. In the packaging industry, the drive controls form-fill-seal machines, cartoners, and case packers—handling rapid start-stop cycles at high throughput rates without mechanical wear.

In automated assembly and robotics, the REXROTH DKC03.3-040-7-FW drives articulated arms, SCARA robots, and linear gantries that require synchronized multi-axis coordination. The Sercos III interface ensures tight phase alignment across all axes, critical for path accuracy. Similarly, in printing and converting machinery, the drive maintains web tension and registration through real-time torque adjustments based on dancer roll feedback.

Its rugged design also suits it for use in foundries, woodworking, and metal forming—environments with high ambient temperatures, dust, and electrical noise. Across all these sectors, the REXROTH DKC03.3-040-7-FW delivers reliable, high-bandwidth motion control that enhances machine productivity, quality, and uptime.

Related Products

• DKC03.3-060-7-FW: 60 A version of the same series; for higher-torque applications.

• MSK040C-0600-NN-M1-UP0: Compatible MSK servo motor often paired with DKC03.3-040-7-FW.

• HCS03.1E-040E-H-B-01: Older HCS drive; predecessor to IndraDrive C, not pin-compatible.

• IndraControl V: Higher-level motion controller that communicates with DKC03.3-040-7-FW via Sercos III.

• DKC03.3-040-7-FW-EC: Variant with EtherCAT instead of Sercos III (custom order).

• MTK040B-0600-N-02: Alternative MTK motor compatible with this drive.

• DKB03.1-040-7-FW: Baseplate/backplane module for mounting multiple IndraDrive C units.

• IndraWorks DSC: Engineering software for configuring and tuning the DKC03.3-040-7-FW.

Installation and Maintenance

Pre-installation preparation: Before installing the REXROTH DKC03.3-040-7-FW, ensure adequate clearance for airflow—minimum 50 mm above and below the unit—and mount it vertically on a grounded metal panel or DIN rail using the optional adapter. Verify that the 3-phase supply meets voltage and imbalance specifications (<2>

Maintenance recommendations: The REXROTH DKC03.3-040-7-FW contains no user-serviceable parts but benefits from periodic inspection of terminal tightness and cooling vents. Use IndraWorks to monitor drive temperature, DC bus voltage, and error logs monthly. If the drive trips repeatedly on overtemperature, check for blocked airflow or excessive ambient heat. Firmware updates should only be performed by qualified personnel using official Rexroth tools—never interrupt power during an update. After any motor or mechanical modification, re-run the auto-tuning routine to optimize current loop gains. Always de-energize and lock out the supply before accessing terminals, as DC bus capacitors remain charged for several minutes after power-off.