Beckwith M-3520 Interconnection Protection Relay

With the large-scale integration of distributed energy (DER) into the distribution network, the protection requirements for interconnected lines are becoming increasingly complex. The distributed power grid interface not only needs to have conventional overcurrent and grounding protection, but also must be able to detect special working conditions such as islanding operation, abnormal power flow, frequency fluctuations, etc., and automatically reconnect to the grid when conditions are met. M-3520 Integrated Protection System launched by Beckwith Electric ® The digital interconnection protection relay designed specifically for this requirement integrates 21 protection functions, synchronization check, reclosing enable, and waveform capture capabilities, providing a complete integrated solution for DER interconnection. Based on the technical specifications, this article systematically analyzes the protection function system, key parameter tuning, and engineering application points of M-3520, providing reference for engineers engaged in distributed energy grid connection and distribution protection.