Latency Characterization and Performance Evaluation of Synchronized Daisy-Chain EtherCAT Networks Using Standard Cable Pairs and Open-Source Master Solutions

EtherCAT is a real-time industrial variant of Ethernet that enables dynamic, time-sensitive data transmission. Most wired Ethernet setups use standard Ethernet cables and the Media Independent Interface (MII) for Layer two connectivity. This work reflects real-world setups that predominantly rely on standard Ethernet pairs cabling and MII connections. The contribution encompasses an empirical evaluation of the performance aspects, exhibited by the EtherCAT network structured upon standard cable pairs technology. This comprehensive assessment is executed through a rigorously designed experimental campaign, specifically tailored for latency measurement purposes. Furthermore, to fortify the analytical approach, the study integrates the methodology of experimental design, a packet analysis tool, and an open-source master controller. A standards-compliant EtherCAT configuration, and a comprehensive experimental campaign was conducted to evaluate network performance, with particular emphasis on latency and robustness under synchronized communication conditions. The results reveal deterministic inter-packet gap measurements of 0.5at the packet layer, a delay of 1.5observed at the frame layer, and physical-layer latency measured at 1.5, under a moderate network load. To ensure rigor and reproducibility, this study combines packet-level trace analysis, open-source EtherCAT masters, and a cost-effective, hardware-independent test setup. A Design of Experiments (DoE) approach was used to assess synchronization performance and identify key parameters.