KONGSBERG RCU Series Modules — RCU510

Technical Dossier

Product Details And Specifications

KONGSBERG RCU Series: Comprehensive Module Range and Technical Overview

The KONGSBERG RCU (Remote Controller Unit) series is a purpose-engineered line of distributed control and remote I/O modules developed by Kongsberg Maritime and Kongsberg Digital for deployment in safety-critical heavy industrial environments. These units are installed across offshore oil & gas platforms, LNG processing terminals, chemical plants, nuclear auxiliary systems, and marine vessel automation systems globally. The RCU architecture forms the backbone of KONGSBERG's K-Chief and SDP (Dynamic Positioning) control ecosystems, providing deterministic real-time communication between field instruments and central processing nodes. Installed base spans multiple decades of continuous operation, making long-term spare parts availability a primary operational concern for asset owners.

The Evolution of RCU Series Architecture

The RCU series originated in the late 1980s as part of KONGSBERG's transition from hardwired relay logic to distributed digital control for marine and offshore applications. Early-generation units such as the RCU100 and RCU200 operated over proprietary RS-485 serial backplanes with limited hot-swap capability. The mid-generation RCU300 and RCU400 families introduced modular I/O expansion, redundant power supply rails, and compatibility with KONGSBERG's KBUS fieldbus protocol. The RCU500 generation — including the RCU510 — represents the mature phase of this architecture, incorporating dual-redundant Ethernet communication, IEC 61131-3 compliant logic execution, and enhanced EMC shielding for harsh marine environments. Later variants in the RCU600 and RCU700 lines introduced PROFINET and Modbus TCP/IP integration, bridging legacy KONGSBERG installations with modern open-protocol DCS platforms. As of 2026, the RCU500 series is in the sustained support phase; original manufacturer production has ceased for most sub-models, making third-party MRO sourcing the primary procurement channel for operators maintaining existing installations.

RCU Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified models within the KONGSBERG RCU product family, classified by functional category:

Remote Controller Units (Main CPU / Controller Modules)

• RCU510: Main remote controller unit, dual Ethernet, IEC 61131-3 logic, marine-grade housing
• RCU500: Base-generation remote controller, single Ethernet port, KBUS backplane interface
• RCU520: Enhanced RCU510 variant with extended temperature range (-25°C to +70°C)
• RCU530: RCU500-series controller with integrated serial gateway (RS-232/RS-485)
• RCU400: Mid-generation controller, proprietary KBUS only, no Ethernet, legacy installations
• RCU410: RCU400 variant with expanded program memory and additional diagnostic LEDs
• RCU300: Early distributed controller, RS-485 backplane, limited I/O expansion slots

Digital Input (DI) Modules

• RCU-DI16: 16-channel 24VDC digital input module, optically isolated, DIN rail mount
• RCU-DI32: 32-channel digital input expansion, high-density format, KBUS interface
• RCU-DI8-ATEX: 8-channel DI module, ATEX Zone 1 certified, intrinsically safe barriers integrated

Digital Output (DO) Modules

• RCU-DO16: 16-channel 24VDC digital output, relay-isolated, 2A per channel
• RCU-DO8-R: 8-channel relay output module, 230VAC rated, for motor starter interfaces

Analog Input / Output (AI/AO) Modules

• RCU-AI8: 8-channel analog input, 4–20mA / 0–10V selectable, 16-bit resolution
• RCU-AO4: 4-channel analog output, 4–20mA, for control valve and actuator interfaces
• RCU-AI4-TC: 4-channel thermocouple input module, J/K/T/E type, cold junction compensated

Communication & Network Adapter Modules

• RCU-PNET: PROFINET IO adapter for RCU500-series backplane integration
• RCU-MBTCP: Modbus TCP/IP gateway module, 32 simultaneous client connections
• RCU-DP: PROFIBUS DP slave adapter, 12 Mbit/s, for legacy DCS integration

Power Supply Modules

• RCU-PSU24: 24VDC redundant power supply module, 10A output, wide-range AC input (85–264VAC)
• RCU-PSU48: 48VDC power supply for marine telecom and alarm panel interfaces

Sourcing Hard-to-Find & Obsolete RCU Series Parts

DriveKNMS maintains a dedicated inventory program for KONGSBERG RCU series components that have reached end-of-production status. For operators running RCU300, RCU400, and early RCU500 installations, OEM replacement parts are no longer available through standard distribution channels. DriveKNMS sources verified surplus, refurbished, and new-old-stock (NOS) units through a global network of industrial asset recovery partners. Each unit is individually inspected, tested against original KONGSBERG functional specifications, and issued with a full test report prior to shipment. Long-term service agreements (LTSA) are available for fleet operators requiring guaranteed stock reservation for multi-year maintenance windows. Emergency same-day dispatch is available for critical offshore and power generation applications.

Quality Control for the RCU Series Range

KONGSBERG RCU modules incorporate complex multi-layer backplane PCBs with proprietary KBUS and Ethernet PHY interfaces that require specialized test procedures beyond standard bench testing. DriveKNMS applies the following verification protocol to all RCU series units:

• Backplane continuity test: Full pin-by-pin verification of KBUS data, address, and power rails against KONGSBERG reference schematics
• Firmware version audit: Identification and documentation of installed firmware revision; compatibility mapping against known RCU500-series software releases
• I/O channel functional test: Each DI, DO, AI, and AO channel is exercised at rated voltage and current using calibrated signal sources and loads
• Communication protocol validation: Ethernet, PROFIBUS, and Modbus interfaces are tested for correct frame structure, timing, and error recovery behavior
• Thermal stress screening: Units are cycled through operational temperature range to identify latent component failures before shipment
• Visual and mechanical inspection: Connector integrity, PCB surface condition, capacitor health, and housing seal condition are documented with photographic records