TCP/IP link - Arc protection - Auto synchronization - Bay control and measurement - Merging unit - Transformer protection - 2 winding - Feeder protection - Voltage regulation - Capacitor bank protection - Petersen Coil control - Grid automation - Busbar differential protection (high impedance) - Back-up protection - Motor protection - Busbar protection (voltage and frequency) - Transformer protection - 3 winding - Interconnection protection - Generator protection - Power management/Load shedding - Modbus Communication Manual - REX640 Protection and control - PCL4 - IEC - ANSI - 16.02.2023

REX640 Modbus Communication Protocol Manual

The protection relay operates as a Modbus TCP/IP server. A Modbus TCP/IP client can establish a connection to the protection relay through the standardized TCP socket port 502.

The Modbus TCP/IP interface of the protection relay can be configured to accept up to five simultaneous Modbus client connections. It is possible to grant connections only to the predefined TCP/IP clients. The write authority of the Modbus TCP/IP client is configurable.

Note: Modbus TCP usually shares the Ethernet connection with the other Ethernet based protocols of the protection relay. The number of Ethernet based clients that can be simultaneously connected to the protection relay is restricted.