Rexroth DKC02.3 Drive Servo Controller

Description

Product Introduction

The Bosch Rexroth Indramat DKC02 is a digital AC servo controller belonging to the widely deployed EcoDrive03 family. Operating over a SERCOS II fiber optic interface, the DKC02 delivers deterministic real-time motion synchronization, precise speed control, and multi-axis positioning for Indramat MKD, MHD, and MKE series brushless servo motors.

Unlike analog or fieldbus-based drive controllers, the DKC02 features an integrated power supply unit that connects directly to 3-phase AC mains (AC 200V to 480V) without requiring a separate transformer. Its fiber optic SERCOS ring eliminates electromagnetic interference (EMI) issues between the central CNC/PLC host and the drive, making it a robust solution for high-noise industrial environments.

Key Technical Specifications

Application Scenarios & The “Trench” Experience

A 5-axis CNC gantry router suddenly trips during a tool change because a kinked glass fiber cable causes a SERCOS ring break (Diagnostic Code F208). In high-speed automated packaging, a single packet loss on an unshielded fieldbus can throw off multi-axis registration—a problem eliminated by the DKC02’s fiber optic SERCOS loop.

• Automotive Body & Assembly Lines – Synchronizes multi-axis robotic welding positioners and transfer shuttles.
• CNC Metalworking & Machining Centers – Drives feed axes and tool turrets with sub-micron positioning feedback.
• Packaging & Material Handling – Controls continuous rotary cutters, cartoners, and high-speed palletizer axes.
• Printing & Converting – Handles web tension and electronic gearing via real-time SERCOS communication.

Real-World Field Case Study

During a busy production run at an automotive stamping facility, a DKC02.3-040 drive threw a persistent F219 (Overcurrent) fault, shutting down a critical loader arm. The local maintenance crew verified that the motor windings were intact, but internal power transistor degradation on the drive’s output stage was tripping the current sense logic.

Replacing the entire motion controller architecture with modern IndraDrive units would have required weeks of software conversion, new cabling, and machine re-validation. Instead, the technician sourced a pre-tested, reconditioned DKC02 drive module. Before swapping the hardware, the engineer transferred the existing FWA firmware card and parameter chip directly from the faulted unit into the replacement unit. By retaining the original parameter module, the replacement DKC02 booted directly onto the SERCOS ring without requiring software downloads or re-commissioning, returning the loader to full operation in less than 45 minutes.

DKC02.3

DKC02.3

Transparency SOP: Quality Assurance & Testing

Every pre-owned or surplus Rexroth DKC02 servo drive undergoes a comprehensive functional testing protocol before shipment:

1. Visual & Mechanical Inspection: Inspect the outer enclosure, cooling fans, heatsink fins, DC bus bars, and fiber optic port connectors for mechanical damage.
2. DC Bus & Power Stage Diode Check: Check main bridge rectifiers, braking resistor IGBTs, and output power transistors for short circuits or electrical stress.
3. Firmware & SERCOS Ring Handshake: Insert an FWA firmware module and connect the drive to a SERCOS test master via fiber optic patch cables to verify phase progression (P0 through P4).
4. Motor Closed-Loop Load Test: Pair the DKC02 with an Indramat MKD servo motor, execute velocity and positioning routines, and test full power acceleration under dynamic braking load.
5. ESD Protection & Secure Shipping: Install protective caps on optical ports, apply anti-static packaging, and secure the heavy module inside reinforced foam containers.

The Veteran’s Tech Trap Guide (Crucial Value-Add)

⚠️ Firmware Card & Parameter Memory: The DKC02 hardware unit does NOT contain operation software out of the box! You MUST install an matching Indramat firmware module (e.g., FWA-ECO33*-SER-03VRS-MS) into the top slot. Always move your old firmware module and parameter chip to the replacement drive when swapping units.

❗ Observe Fiber Optic Bending Radius: The SERCOS interface uses optical fiber jumpers (TX/RX). Bending the fiber cable sharper than a 30mm radius will fracture the glass core, resulting in F208 or F218 SERCOS ring communication errors.

⚠️ DC Bus Residual Voltage Hazard: After turning off 3-phase mains power, high voltage remains on the internal DC bus capacitors (across terminals L+ and L-) for several minutes! Always measure the DC bus voltage with a multimeter and ensure it drops below 50VDC before disconnecting motor or power cables.

❗ Proper Grounding & Shielding: Connect the motor power cable shield directly to the grounding clamp on the DKC02 housing. Floating or improperly grounded motor shields allow high-frequency PWM switching noise to pass into encoder cables, triggering F226 or F700 encoder signal faults.

Frequently Asked Questions (FAQ)

Q: What is the primary difference between a DKC01 and a DKC02 drive?

A: The main difference lies in the master communication interface. The DKC01 uses analog (±10V) or parallel interface controls, whereas the uses a digital SERCOS II fiber optic interface ring for real-time digital synchronization.

Q: What does error code F208 mean on my DKC02 LED display?

A: F208 indicates a “SERCOS Interface Ring Break”. This means the fiber optic loop between the controller and drive is open. Check for damaged fiber cables, loose TX/RX plugs, or a powered-down drive higher up in the ring.

Q: Can I replace a DKC02.1 or DKC02.2 with a DKC02.3 model?

A: In most cases, yes, as the .3 indicates the hardware revision generation within the EcoDrive03 series. However, you must ensure that the current rating (e.g., 040 = 40A) matches and that your firmware version supports the newer hardware release.

Q: Do I need a separate power supply unit to operate a DKC02 drive?

A: No. Unlike older Indramat modular systems (like the MAINDRIVE or DIAX04), the EcoDrive DKC02 has a built-in power supply that connects directly to 3-phase AC mains.

Q: What warranty is provided with surplus or refurbished Rexroth DKC02 drives?

A: All tested surplus and refurbished Rexroth Indramat DKC02 servo drives supplied through our channel include a full 12-month operational replacement warranty.

Q: Why replace with a refurbished DKC02 instead of upgrading to an IndraDrive C system?

A: Upgrading to IndraDrive requires replacing motor feedback cables, updating host PLC software, and modifying control cabinet layouts. Sourcing a direct-fit DKC02 replacement restores factory operations instantly at a fraction of the cost and downtime.