Serbia Voz continues to modernize its passenger fleet with five new Soko high-speed electric trains manufactured by CRRC (China). Operational safety is ensured by our RAS90 system with PZB90 functionality, developed and delivered in compliance with SIL2 safety requirements. The system is fully integrated and successfully communicates with TCMS, JRU, and ETCS. A key technical milestone of the project is the dynamic transition between the Class B PZB90 system and ETCS, enabling seamless operation across different signalling environments. Another solid step toward interoperable, high-speed, and safe rail transport in the region.