(e)_0004_Annex_4_20260608.pdf

This is a technical specification annex for a repair work order related to medium voltage (MV) SF6 breakers at an Italian military installation (Caserma Del Din).

The document specifies the REF620 relay as the required protection and control device for this work. The REF620 is a dedicated feeder management relay designed for protection, control, measurement, and supervision of utility and industrial power distribution systems, including radial, looped, and meshed networks with or without distributed power generation. The relay supports a comprehensive range of functionalities including overcurrent protection, earth-fault protection, thermal overload protection, voltage protection, frequency protection, fault location, high-impedance differential protection, interconnection protection, capacitor bank protection, arc protection, load-shedding, synchro-check, and auto-reclose capabilities. The relay features a modular design with withdrawable plug-in units for swift installation and testing, operates with IEC 61850 Edition 2 and Edition 1 support for communication and interoperability, and provides IEEE 1588 V2 for high-accuracy time synchronization. The REF620 supports multiple communication protocols including IEC 61850-9-2 LE, IEC 60870-5-103, Modbus, DNP3, and Profibus DVP1. Key customer benefits include compact and versatile design, wide application coverage for various feeder types, extensive protection and control functionality, and extensive life cycle services. The relay is designed to serve as the main overcurrent and earth-fault protection device for overhead lines and cable feeders in single or double-busbar applications.