Assessing locomotive compatibility under increased overhead line voltage
Customer: SJ AB, Sweden
End customer: Trafikverket, Sweden
Project tasks
- Technical investigation
- Documentation research
- Identification of possible changes in locomotive high-voltage circuits
- Cost estimation of the changes
- Integration of the changes in the actual system
Our approach
PROSE began with a structured review of the Rc6 high-voltage system, analysing design documentation, component specifications, and historical modification records to establish the vehicle’s current technical baseline. Based on this analysis, we evaluated the impact of the increased maximum voltage on insulation coordination, component voltage margins, and protection systems. Where necessary, we developed alternative technical solutions to ensure compliance with the new operating conditions. Each option was assessed from both a technical and economic perspective, including feasibility, implementation effort, operational implications, and associated risks. The work was carried out in close dialogue with SJ as operator and Trafikverket as infrastructure owner to ensure transparency and alignment throughout the project.
Customer benefit
The customer gained a transparent and technically sound decision basis for operating the Rc6 fleet under increased overhead line voltage. Our independent assessment clarified voltage margins, component limitations, and protection requirements, creating full visibility of technical risks and modification needs.
By systematically comparing refurbishment scenarios, including cost and implementation implications, we enabled SJ and Trafikverket to prioritise measures based on safety, operational reliability, and long-term investment protection. With PROSE’s in-depth knowledge of Swedish rolling stock and infrastructure interfaces, the operators secured a technically robust and future-proof solution aligned with updated network standards.











