GE Multilin UR Series L90 Line Current Differential Protection Relay

Product Description

The GE Multilin L90 is a high‑performance line current differential protection relay developed by General Electric for transmission lines and cables across multiple voltage levels. It is engineered to deliver fast, secure, and reliable protection, combining advanced differential and distance protection functions with modern communication capabilities.

This relay supports synchronized sampling, adaptive restraint, and inter‑relay communication, ensuring dependable operation even under challenging network conditions. With integrated synchrophasor support and compliance with IEEE C37.118 and IEC 61850‑90‑5 standards, the GE Multilin L90 is suitable for utilities and industrial power systems requiring precise fault detection and system stability.

Technical Specifications

• Model / Order Number: L90

• Manufacturer: General Electric (GE Multilin)

• Type: Line Current Differential Protection Relay

• Protection Functions:

• High‑speed current differential protection for transmission lines and feeders

• Distance protection with 5 zones (phase and ground)

• Dual‑breaker applications with single and three‑pole tripping

• Adaptive restraint for internal vs. external fault discrimination

• Communication Features:

• Synchronized sampling across relays

• Inter‑relay communication via fiber and multiple interfaces

• Synchrophasor (PMU) support per IEEE C37.118 (2011) and IEC 61850‑90‑5

• Sensitivity Enhancements:

• Dynamic charging current compensation

• Communication channel asymmetry compensation

• Design: Phase‑segregated differential protection for secure high‑speed tripping

Application Scenarios

• Transmission line protection in utility networks

• Cable protection across varying voltage levels

• Dual‑breaker configurations requiring single or three‑pole tripping

• Power system monitoring with synchrophasor integration

FAQ

Q: What type of protection does the GE Multilin L90 provide?  A: It offers line current differential protection, distance protection, and synchrophasor support.

Q: Can the relay handle dual‑breaker applications?  A: Yes, it supports both single and three‑pole tripping scenarios.

Q: How does the relay maintain sensitivity during external faults?  A: Through adaptive restraint and dynamic compensation features.

Q: Does the L90 support synchrophasor measurements?  A: Yes, it complies with IEEE C37.118 and IEC 61850‑90‑5 standards.