Yokogawa Electric Corporation SNT401-53 Optical Bus Repeater Module

The Yokogawa SNT401-53 S1 Optical ESB Bus Repeater Module extends ESB communications between safety controllers and remote I/O in ProSafe-RS and CENTUM VP systems by converting electrical ESB signals into optical signals for fiber-optic transmission. It uses fiber optic cable (multi-mode or single-mode) to deliver high-speed, noise-resistant communication over long distances, with typical distances up to ~5 km and up to ~10 km depending on system, and it supports star and chain network topologies for flexible deployments. The 2-channel ESB bus module draws power from the host system (5 VDC or 24 VDC, system dependent) and is designed for rack- or panel-mount installations, with an operating temperature range of approximately -20 to 60–70 °C (config dependent) and an ISA G3 corrosion-resistant coating for demanding industrial environments. Intended for oil & gas, LNG plants, chemical processing, and power generation, it reliably extends distance and preserves signal integrity between safety controllers and remote I/O nodes in electrically noisy or large-scale installations.