Station communication - Arc protection - Bay control and measurement - Merging unit - Transformer protection - 2 winding - Feeder protection - Voltage regulation - Capacitor bank protection - Grid automation - Busbar differential protection (high impedance) - Line differential protection - Back-up protection - Motor protection - Busbar protection (voltage and frequency) - Interconnection protection - Generator protection - Power management/Load shedding - Operation Manual - REX615 Protection and control - Relion Protection and Control - PCL2 - IEC - ANSI - 01.04.2026

REX615 Operation Manual

Operational information and control functions are available through a wide range of communication protocols, including IEC 61850 Edition 2, IEC 61850-9-2 LE, IEC 60870-5-103, IEC 60870-5-104, Modbus® and DNP3. Full IEC 61850 communication capabilities — such as horizontal communication between relays — are enabled exclusively through IEC 61850.

The relay provides support for two independent physical networks when communication modules with three Ethernet ports (COM8…COM10, COM15…COM18, COM31…34 and COM37) are used. These two networks can be assigned separate IP address ranges, allowing clear separation of operational traffic — for example, one network dedicated to SCADA/dispatching and the other to engineering or maintenance access.

In addition to the two physical network interfaces, the relay supports up to five VLAN interfaces, which operate as logical communication interfaces within Network1. VLAN interfaces can be used to segment traffic as needed into logically separated Ethernet networks.

Only one interface default route can be configured in the device. To support more complex communication architectures, the relay also allows configuration of up to 10 additional static routes, enabling traffic to be directed toward specific destination networks in addition to the interface default route.

The IEC 61850 protocol forms a central part of the relay’s protection and control functionality and is fully based on standardized data modelling. The relay supports both Edition 1 and Edition 2 of the standard. With Edition 2, the relay offers enhanced functionality for modern substation automation and improved interoperability. Flexible Product Naming (FPN) is supported, enabling customized adaptation of the IEC 61850 data model to project-specific naming conventions.