Modular Axle Counting Systems for Digital Interlocking Architectures

Voestalpine Railway Systems has developed the UniAC[2] axle counting system to provide an interoperable, modular solution for modern railway signalling infrastructure. The system utilizes standardized interfaces to integrate into multi-vendor digital interlocking architectures, addressing the industry demand for open, scalable infrastructure.

Modular Architecture and EULYNX Compliance
The UniAC[2] system separates trackside detection from the central evaluation logic to align with EULYNX architectural standards. The field-installed UniAS[2] wheel sensor performs physical wheel detection under varied environmental conditions, while the separate AXM module manages the safety-critical counting logic, data evaluation, and network integration. By decoupling these functions along defined interfaces, the architecture allows infrastructure managers to integrate the system directly into multi-vendor digital interlocking environments, reducing reliance on proprietary, single-source signaling platforms.

Interface Standardization and Maintenance Protocols
The system utilizes standardized interfaces to limit interface diversity and establish clear boundaries between signaling components. Pre-configured, plug-and-play components minimize the engineering overhead required to connect the system to new or existing digital interlocking networks. To maintain operational availability, the hardware modules feature hot-swapping capabilities. This allows technical personnel to replace modules during live operations without requiring manual reconfiguration or system downtime. The scalable topology also permits the addition of new counting points to the network without modifying the core system architecture.

Safety Certification and Industry Presentation
Demonstrated at the InnoTrans exhibition in Berlin in September 2026, the axle counting system is certified to Safety Integrity Level 4 (SIL4) standards. This certification provides the necessary safety integrity required for primary train detection and track vacancy signaling in high-density mainline and transit rail networks.

Additional Context: Technical Specifications and Competitive Benchmarking
Modern axle counting systems for rail transport must increasingly support standardized interfaces in accordance with the European EULYNX initiative. The featured system competes directly with established SIL4-certified axle counters, such as the Thales AzLM (now Ground Transportation Systems) and the Frauscher Advanced Axle Counter (FAdC).

While traditional systems like the AzLM frequently require proprietary transmission protocols and dedicated copper cable connections, newer architectures like the FAdC and the presented system rely on IP-based network interfaces. The critical differentiator lies in native EULYNX compliance: the system described here utilizes standardized software-defined interfaces (Object Controller interfaces according to EULYNX Baseline 3 or higher) to ensure direct interoperability between the axle counter and interlockings from different manufacturers without the need for proprietary protocol converters. Compared to older generations where a module replacement often requires trackside calibration, the combination of pre-configured plug-and-play components and hot-swapping reduces the Mean Time to Repair (MTTR) in the field to a minimum.

Edited by Evgeny Churilov, Induportals Media - Adapted by AI.

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