Beckwith Electric M‑3520 Intertie Protection Relay
The Beckwith Electric M‑3520 is a microprocessor‑based intertie protection relay designed for utility and distributed generation interconnections. It provides comprehensive protection for the point of common coupling (PCC) between a generator or industrial plant and the utility grid. The relay includes directional overcurrent, over/undervoltage, over/underfrequency, and reverse power functions, ensuring safe and reliable interconnection.
This relay is compliant with IEEE 1547 and other interconnection standards, making it suitable for renewable energy projects, co‑generation plants, and emergency standby systems. The M‑3520 features high‑accuracy measurements, fault recording, and multiple communication protocols.
Key Features
Protection functions: 50/51, 67, 27, 59, 81, 32, and 46
Directional overcurrent for fault detection
Voltage and frequency ride‑through settings
Programmable logic and setting groups
Fault recorder with oscillography
Communication: Modbus, DNP3, IEC 61850
Large LCD with local control
Technical Specifications
CT inputs: 1A/5A; PT inputs: 100–480 VAC; frequency: 50/60 Hz; power supply: 125/250 VDC or 120/240 VAC; accuracy: ±1%; output relays: 8 programmable; operating temperature: -20°C to +70°C.
Applications
Used for utility interconnections, distributed generation (solar, wind, gas), and industrial co‑generation. The relay ensures grid stability and protects both utility and customer equipment.
Installation and Configuration
Mount the relay in a standard panel. Connect CTs, PTs, and control wiring. Use Beckwith’s BESTCOMS software for detailed configuration and logic programming.
Reliability and Maintenance
Designed with self‑diagnostics and surge protection. Periodic testing using secondary injection is recommended.
Why Choose the M‑3520?
This relay offers a robust solution for intertie protection, meeting the latest standards. Its flexible settings and communication make it ideal for modern grid integration.
In summary, the Beckwith Electric M‑3520 provides reliable and compliant protection for grid‑connected generation systems.
