What construction features and performance characteristics define the specialized cable designed for railway rolling stock applications as shown?

The railway rolling stock cable exhibits a multi-layered architecture optimized for dynamic mechanical stress and electrical reliability. Its core consists of Class 5 flexible stranded copper conductors (≥19 strands) insulated with cross-linked polyethylene (XLPE), providing thermal stability up to 125°C and resistance to hydrolysis in humid environments. A tinned copper braid serves dual functions: 90%+ electromagnetic interference (EMI) shielding and supplementary mechanical reinforcement against abrasion during bogie movement.   The outer sheath employs flame-retardant ethylene propylene diene monomer (EPDM) rubber, formulated to meet EN 45545-2 HL3 fire safety requirements—including low smoke density (<500%/m) and halogen-free combustion. The cable’s design incorporates a helical lay of insulated cores with a central strength member, reducing torsional stress during train articulation while maintaining a minimum bending radius of 6× cable diameter for tight routing in confined railcar spaces. Voltage rating is specified at 3kV AC (50Hz) with impulse withstand capability up to 25kV, suitable for power transmission between traction converters and motors in electric multiple units (EMUs).   Installation certifications include compliance with UIC 502-2 for railway applications and DIN EN 50306 for low-voltage cables in rolling stock, ensuring compatibility with global rail networks from high-speed trains to urban light rail systems.