MJR Power & Automation and ELSYS Complete ABS-Approved Life Extension and Repowering of Specialist Research Vessel

MJR and ELSYS delivered a turnkey electrical, propulsion & automation modernisation for the vessel supporting the world’s only fully ocean-depth rated manned submersible.

The vessel was redelivered to its owner in March 2026 with full approval and certification from classification society ABS.

The project spanned design, engineering, construction, installation, commissioning, certification and testing, and marks a major step in the modernisation of one of the world’s most technically capable deep-ocean research platforms.

Key Outcomes

• Redelivered with full ABS approval in March 2026
• Complete rebuild of the vessel’s electrical power, propulsion, automation and power management systems
• Extended the vessel’s operational life
• Improved redundancy, maintainability and long-term supportability
• Successful integration of modern systems into legacy marine infrastructure

A Comprehensive Turnkey Upgrade

The scope of work covered a complete modernisation of the vessel's electrical power, propulsion, automation, and control and monitoring systems.

This included the in-situ rebuild of the main 600V propulsion switchboard and DC propulsion drives, the 450V ships services switchboard, the 450V emergency switchboard, generator control systems, 24VDC and UPS systems, and the bridge and engine control room (ECR) control desks, together with the integration of an advanced vessel-wide automation and power management system.

Throughout 2024, MJR carried out the basic and detailed design, including single line diagrams, switchboard schematics, short circuit calculations, protection studies, load balance and harmonic compensation, alongside the I/O and alarm lists, IAS mimic screen design and PMS system design.

Electrical hardware was manufactured at MJR Power & Automation's Teesside facilities, while the automation system was built at ELSYS's facilities in Vigo, Spain. MJR was responsible for ABS approval of the full electrical power and automation design, with the IAS/PMS factory acceptance testing carried out at ELSYS in Vigo.

Installation and commissioning took place in 2025 and early 2026 at Astican Shipyard, Las Palmas de Gran Canaria, Spain.

Rebuildingthe Heart of the Vessel

The team extensively modified the main 600V switchboard, replacing all switchgear, control gear, instrumentation and switchboard doors. Because the original equipment differed in physical form factor to the modern drives and circuit breakers, significant internal reconfiguration of the original enclosures was required.

The main propulsion and bow thruster DC variable-speed drive systems were replaced with enhanced redundancy features built in. Each main propulsion motor has duty and standby field drives, while a newly designed armature changeover system allows both motors to operate from a single armature drive in the event of a failure. A new feeder allows the bow thruster to draw power from either the port or starboard bus, giving the vessel dual redundant thruster feeds and the main switchboard has been reconfigured into three splits with the addition of bus tie circuit breakers.

To enhance power quality, two active harmonic filter units were installed adjacent to the 600V main switchboard, protecting sensitive deepwater survey consumers and dramatically improving efficiency, by improving harmonic power factor.

Modernised Bridge and Engine Control Room

New control plates and backplates were installed across the ECR desk and bridge centre console, providing updated interfaces for propulsion control, steering gear and vessel monitoring. Both bridge wings were upgraded with new user interfaces for main propulsion, bow thruster and rudder angle indication.

VAMOS: A New Automation Backbone

The vessel's legacy automation system was replaced with VAMOS, the Vessel Automation and Machinery Operating System developed by ELSYS. The platform delivers integrated power and energy management alongside comprehensive alarm, monitoring and control coverage spanning generation, propulsion, bilge, watertight doors, fridge and freezer spaces, fire detection, firefighting and general ship services.

The system architecture is built around two redundant fibre-optic ring networks; one serving the operator stations and engineer alarm stations, the other the PLC and distributed I/O system. No two servers or operator stations share a common network switch, so no single failure can take down essential services. Four main operator stations are located throughout the vessel, supported by five cabin alarm panels for the new extension alarm system.

New UPS systems at the ECR desk and on the bridge provide protected power to the automation servers and operator stations, while a new 24VDC automation supply delivers control power throughout the vessel, with continuous insulation monitoring from the ECR console.

Project Significance

This project demonstrates MJR and ELSYS's combined ability to deliver complex, class-approved electrical power, propulsion and automation upgrades on highly specialised vessels where reliability, redundancy, maintainability and regulatory compliance are critical.

By combining modern power management, upgraded propulsion drive systems, active harmonic mitigation, redundant automation architecture and enhanced generator control, the project has extended the operational life of the vessel while improving system resilience, operational flexibility and long-term supportability — reinforcing MJR and ELSYS as trusted partners for complex marine electrical power, propulsion and automation modernisation projects.

The upgrade extends the vessel’s operational life while making it easier to maintain and support for years to come. For MJR and ELSYS, it demonstrates their combined ability to deliver complex, class-approved electrical power, propulsion and automation upgrades on highly specialised vessels — where reliability, redundancy and regulatory compliance are non-negotiable.

Read the full project case note: ABS-Approved Life Extension & Repowering of Specialist Research Vessel For further details, contact: sales@mjrpower.com | +44 (0)1642 762151