Overview - 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 - PCL2 - IEC - ANSI - 01.04.2026

REX615 Operation Manual

REX615 is a product family of relays designed for protection, control, measurement and supervision of utility substations and industrial switchgear and equipment. The design of the relay has been guided by the IEC 61850 standard for communication and interoperability of substation automation devices.

The relays feature a draw-out-type design with a variety of mounting methods, compact size and ease of use. REX615 offers two different relay size variants, standard and wide. Relay size variant and module content can be selected ac-cording to application needs. Relay application functionality can be selected independently from the selected hardware content according to the protection application needs.

The REX615 relays support a range of communication protocols including IEC 61850 with Edition 2.1 support, process bus according to IEC 61850-9-2 LE or IEC 61869-9, IEC 60870-5-103, IEC 60870-5-104, Modbus® and DNP3. Profibus DPV1 communication protocol is supported by using the protocol converter SPA-ZC 302.