Eaton ETR-4000-2A3GB0 Transformer Relay - Modbus RTU over RS-485

Eight digital inputs and nine digital outputs are integrated into the relay, delivering centralized control and status monitoring. This consolidation reduces external wiring, lowers installation time, and clarifies fault diagnostics in protection schemes. The relay is ideal for transformer protection in substations and OEM equipment where reliable I/O is critical, including two current sensing inputs. Modbus RTU or DNP3 RTU communication over RS-485 via D-Sub connectors provides flexible, standards-based network integration. It enables seamless SCADA or historian integration, improved remote diagnostics, and easier migration from legacy relays. The communication capabilities support plant-wide protection schemes, ensuring data-rich alarms and events reach control systems with minimal latency. Wide power supply range supports 19-300 Vdc and 40-250 Vac, with 50/60 Hz operation, accommodating mixed-voltage environments and reducing inventory for global installations. It is suitable for substations, machine controls, and distributed energy systems that experience voltage fluctuations. Conformal-coated circuit boards further enhance reliability in dusty or humid industrial settings, reducing corrosion risk over the product life. Conformal coating, removable terminals, and semi-flush mounting improve field serviceability and installation flexibility. This simplifies retrofits, shortens downtime during maintenance, and enhances mechanical compatibility with existing enclosures. It is ideal for harsh production floors and outdoor installations where serviceability matters. I/O options include Sensitive Ground Input, Trip Coil Monitor, URTD Interface, and IRIG-B timing. These features provide precise protection sequences, enhanced event logging, and accurate time stamping for diagnostics and reporting. Application scenarios include critical protection in substations and industrial plants requiring robust coordination and timing accuracy. Zone Selective Interlocking (2) supports coordinated fault clearance, reducing outage duration and improving system reliability for feeder protection in distribution networks where uptime matters.