Parameter setting group selection - 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

In the current protection relay version, parameter setting group selection and reading is defined through regular Modbus registers. Formerly this was achieved by a special 4x register 9231. The new register has the default address 2301. See the protection relay documentation for the number of available setting groups. Exception response 3 is given if the written value is out of range or the setting group changing is blocked.