The L90 provides high-speed current differential protection suitable for transmission lines and cables of various voltage levels, while supporting complete distance protection and dual-breaker applications suitable for single and three-pole tripping applications. The L90 uses synchronized sampling at each relay to limit the impact of communications channel issues. The differential element's adaptive restraint balances sensitivity for internal faults and security during external faults. The L90 supports inter-relay protection communications via direct fiber as well as different interfaces.

Key Benefits

• Phase-segregated differential protection ensures secure high-speed single-pole tripping
• High-speed cost-effective five zones quad or mho, phase and ground distance protection with multiple standard and customizable pilot schemes support
• Reliable and secure protection on lines equipped with series compensation
• Increased sensitivity through dynamic charging current compensation and communication channel asymmetry compensation
• Phasor Measurement Unit (synchrophasor) according to IEEE C37.118 (2011) and IEC 61850-90-5 support
• Three independent fiber or copper Ethernet ports for simultaneous/dedicated network connections with 1 microsecond time synchronization via LAN with IEEE 1588 support
• CyberSentry™ provides high-end cyber security aligned to industry standards and services (NERC CIP, AAA, Radius, RBAC, Syslog)
• AAdvanced IEC 61850 Ed. 1 and Ed. 2 certified implementation, complete settings via SCL files and flexible process bus support (IEC 61850-9-2LE or IEC 61850-9-2 Hardfiber) ensures interoperability, device managing optimization and reduced cost of ownership
• Routable GOOSE (R-GOOSE) enables GOOSE messages going beyond the substation, which enables wide area protection and control applications
• Application flexibility with multiple I/O options including high density I/O, programmable logic, modularity, and specific customization
• An integrated large, full color display, provides real-time visualization and control of the protected bay, via a bay mimic as well as annunciator functionality and graphical visualization of phasors

Applications

• Overhead lines including series-compensated lines and underground cables of different voltage levels
• Circuits with tapped transformer feeders
• Suitable for three-terminal line configurations, with channel redundancy and direct transfer tripping (DTT)
• Wide area system monitoring and control and using integrated protection and synchrophasor measurement
• Single and dual-breaker circuits requiring single/three-pole autoreclosing and independent synchrocheck supervision
• Secure application with Capacitively-Coupled Voltage Transformers (CCVTs)

L90 là thành viên của rơ le bảo vệ GE họ UR. L90 cung cấp khả năng bảo vệ chênh lệch dòng điện tốc độ cao phù hợp với các đường dây và cáp truyền tải ở các cấp điện áp khác nhau, đồng thời hỗ trợ bảo vệ khoảng cách hoàn toàn và các ứng dụng ngắt kép. Nó lý tưởng cho các ứng dụng HV, EHV và UHV trên đường dây và cáp có độ dài bất kỳ cho các ứng dụng 1 hoặc 2 CB. L90 tích hợp một màn hình LCD màu lớn và PMU.