MJR Power & Automation and marine automation specialist ELSYS have successfully completed a two-year turnkey life extension and repowering project for a specialist research 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
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.
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.
