ABB RDCU-02C – Drive Control Unit for ACS800 Systems and Multidrives

The ABB RDCU-02C is a control unit module used across many ACS800 drive cabinets and multidrive configurations. From my experience, it serves as the “brain” that coordinates power modules, handles DDCS fiber communication, and ties in optional I/O and fieldbus adapters. If you’re maintaining older ACS800 lines in metals, pulp & paper, marine, or large HVAC plants, this module typically drops in with minimal disruption and brings a tired system back into sync.

One thing I appreciate is how predictable the swap is: back up parameters, observe ESD discipline, move the fiber links and harnesses over, then restore the configuration. A maintenance lead at a pulp mill mentioned they were back online within an hour, which seems to be a common outcome when the firmware alignment is planned ahead.

Company’s Order Placement Process and Guarantees

• Warranty: 365 days
• Delivery time: 1 week for in-stock items; no more than one month at the latest
• Payment: 50% advance payment; full payment prior to delivery
• Express options: FedEx, UPS, DHL

Key Features

• DDCS fiber optic control backbone – Manages high-speed communication between inverter/rectifier modules in ACS800 systems.
• Seamless ACS800 integration – Typically used in cabinet-built multidrives and module-based configurations where centralized control is preferred.
• Fieldbus flexibility via options – Supports PROFIBUS DP, DeviceNet, and LonWorks through ABB option boards, allowing easy tie-in to existing PLC networks.
• Parameter and firmware management – Stores drive parameters and runs firmware suited to the installed power modules; plan for revision matching during replacement.
• Works with ABB I/O boards – When paired with the correct I/O, you get the usual 0–10 V / 4–20 mA analog, 24 VDC digital I/O, and relay outputs for plant signals.
• Service-friendly form factor – Board-level module designed for internal mounting, with clear connectors for fibers and harnesses.
• Reliable in industrial environments – In most cases supports cabinet temperatures up to 55 °C when properly ventilated and within ABB’s enclosure guidelines.

Technical Specifications

Related or Supporting Products

• ABB RDCU-12C – Alternative control unit variant used in other ACS800 configurations; choose based on drive frame and firmware requirements.
• ABB RMIO-02 – I/O board providing analog/digital/relay I/O; pairs with the control unit for plant signal interfacing.
• ABB RDCO-02 – DDCS communication module used for expanding fiber optic links within multidrive systems.
• ABB FPBA-01 (PROFIBUS), FDNA-01 (DeviceNet), FLON-01 (LonWorks) – Fieldbus adapters the RDCU supervises for PLC connectivity.
• ABB ACS-CP-02 – Local control panel for parameter editing and diagnostics; useful for backups prior to swapping the RDCU.

Installation & Maintenance

• Cabinet environment: Mount inside an ABB-compliant enclosure with adequate ventilation; maintain ambient typically within 0…+55 °C.
• Wiring & fibers: Respect DDCS fiber bend radius and keep fibers clean; route low-voltage signal harnesses away from high-EMI power cables.
• ESD handling: Use a grounded wrist strap and ESD-safe work area; the RDCU is sensitive to improper handling.
• Parameter backup: Save the parameter set to the panel or a service tool before removal; restore and verify after installation.
• Firmware alignment: Match the RDCU firmware to the drive system level; in many cases, an update or downgrade may be needed for smooth startup.
• Routine maintenance: Periodically inspect and clean connectors with dry air, check fiber terminations, and review event logs for intermittent errors.

Quality & Certifications

• Standards: Designed for use within ABB ACS800 systems that carry CE and UL/cUL approvals.
• Material compliance: RoHS-compliant design in most production batches.
• Manufacturer support: ABB documentation and lifecycle services available for long-term maintainability.
• Warranty: 365-day warranty from shipment as stated above.