The L90 provides high-speed current differential protection suitable for transmission lines and cables of
various voltage levels, while supporing 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.
Phase segregated differential protection ensures secure high-speed single pole tripping
Complete IEC 61850 Process Bus solution providing resource optimization and minimizing total P&C life cycle costs
Reliable and secure protection on lines equipped with series compensation
Increased sensitivity through dynamic charging current compensation and communication channel asymmetry compensation
Advanced fault and disturbance recording, including internal relay operating signals thus eliminating the need for external recording devices
Phasor Measurement Unit - Synchronized phasor information according to IEEEC37.118 standard
Robust network security enabling Critical Infrastructure Protection through user command logging, and dual permission access control
Ambient temperature monitoring with alarming when outside temperature exceeds upper thresholds
The L90 supports English, French, Russian, Chinese and Turkish languages on the front panel
Overhead lines including series compensated lines and underground cables
Circuits with tapped transformer feeders
Distributed busbar protection
Suitable for three terminal line configurations
Wide area system monitoring and control
Single and dual-breaker circuits
Phase segregated line current differential with adaptive restraint & Ground differential
Stub bus protection
Phase Distance (three Zones) with independent compensation settings for in-zone power transformers
Ground distance (three zones) with independent self and mutual zero sequence compensation
Out-of-step tripping and power swing blocking
Directional overcurrent: Phase, neutral and negative sequence
Synchronism check for dual breaker applications
The L90 is a high-end cost effective line current differential protection relay intended for transmission lines and cables of different voltages levels providing reliable and secure operation even under the worst case power system conditions. The L90 provides high-speed phase-segregated fault clearance suitable for single and three-pole tripping applications. Part of the Universal Relay family, the L90 comes with a variety of versatile features truly integrating protection, monitoring, metering, communication and control in one easy-to-use device. The Universal Relay family offers a high degree of modularity in its design and functionality providing superior performance in protection and control meeting the toughest requirements of the marketplace.
Real time monitoring of remote, local and differential per phase currents
Oscillography - 64 samples/cycle, up to 64 records
Event Recorder - 1024 time tagged events, with 0.5ms scan of digital inputs
Data Logger - Up to 16 channels with user selectable sampling rate
P & M Class synchrophasors of voltage, current and sequence components – 1 to 120 frames/sec
The L90 is the single point for protection, control, metering, and monitoring in one integrated device that can easily be connected directly into DCS or SCADA monitoring and control systems like Viewpoint Monitoring as shown..
The L90 incorporates advanced automation features including powerful FlexLogic™ programmable logic, communication, and SCADA capabilities that far surpass what is found in the average line relay. The L90 integrates seamlessly with other UR relays for complete system protection.
Flexlogic™ allows for customizing the L90 to operate and control the breakers and other auxiliary devices needed to fit most line protection schemes and applications.
Multiple Protocols - IEC61850, DNP 3.0 Level 2, Modbus RTU, Modbus TCP/IP, IEC60870-5-104, Ethernet Global Data (EGD)
Direct I/O – secure, high-speed exchange of data between URs for Direct Transfer Trip applications
Embedded Managed Ethernet Switch with 4 - 100 Mbit Fiber optic ports and 2 copper ports
The L90 provides for secure remote data and engineering access, making it easy and flexible to use and integrate into new and existing infrastructures. Fiber optic Ethernet provides high-bandwidth communications allowing for low-latency controls and high-speed file transfers of relay fault and event record information. The available redundant Ethernet option and the embedded managed Ethernet switch provide the means of creating fault tolerant communication architectures in an easy, cost-effective manner.
The L90 supports the most popular industry standard protocols enabling easy, direct integration into monitoring and SCADA systems.
IEC 61850
DNP 3.0
Ethernet Global Data (EGD)
IEC 60870-5-104
Modbus RTU, Modbus TCP/IP
In addition to providing high-speed connectivity directly to your Universal Relay, the MultiLink UR Switch module provides an additional 4 Fiber Ethernet ports, for connection to other relays in the system as well as upstream connectivity. It also provides 2 RJ-45 copper Ethernet ports which can be used to connect local devices such as PCs, meters, or virtually anything else in the system.
The UR Switch provides a simple way to add fully-managed Ethernet networking to your relays and devices without the need for additional hardware or a dedicated communications cabinet.
The UR Switch includes all the management and features that come with all MultiLink managed switches, and can be easily integrated into a network that has other Ethernet switches.
When used in a ring topology with other UR switch modules or MultiLink switches, the UR Switch can be configured to use MultiLink’s Smart RSTP feature to provide industry-leading network recovery for ring topologies, at a speed of less than 5ms per switch. Learn More
Use the L90 with integrated IEC 61850 to lower costs associated with generator protection, control and automation. GE’s leadership in
IEC 61850 comes from thousands of installed devices and follows on years of development experience with UCA 2.0.
The L90’s IEC 61850 Process Bus module is designed to interface with the Multilin HardFiber System, allowing bi-directional IEC 61850 fiber optic communications. The HardFiber System is designed to integrate seamlessly with the existing Universal Relay applications, including protection functions, FlexLogic, metering and communications. Learn More
The EnerVista™ Suite is an industry-leading set of software programs that simplifies every aspect of using the L90 relay. The EnerVista™ suite provides all the tools to monitor the status of the protected asset, maintain the relay, and integrate information measured by the L90 into DCS or SCADA monitoring systems. Convenient COMTRADE and Sequence of Events viewers are an integral part of the UR Setup software included with every UR relay, to carry out postmortem event analysis to ensure proper protection system operation.Learn More
Access Control
Multilin devices and relays are designed with simple but powerful security to enable reliability and compliance for virtually any project or implementation. With support for multi-level permissions and multi-factor supervisory controls, Multilin devices can help you manage the integrity of your system during commissioning, testing, implementation, and beyond.
The UR Family provides separate authentication for settings and commands to the system. In addition, as discrete authentications for local and remote access, it also provides a supervisory control factor that can lock or unlock a device for configuration changes and other modifications.
Intrusion Detection
Multilin’s family of protection and control products can also help enable your security perimeter and intrusion detection programs. By providing essential alarming and logging of critical events, Multilin devices can help you detect potential breaches within your system and allow you to respond quickly and effectively. Specifically, unsuccessful access attempts are logged, alarmed, and lead to potential attackers being locked out. This ensures the reliability of your system during questionable activity.control factor that can lock or unlock a device for configuration changes and other modifications.
Auditing and Reporting
With the Security Audit Trail reporting feature and support for Event logging of key
activities such as configuration changes, Multilin devices can help ensure device and
protection system integrity, and perform forensic auditing of activities and changes
for compliance.
Fully Compatible with GE's Multlilin HardFiber System
- Provides support for GE's
IEC 61850 HardFiber Process Bus Solution:
- Complete IEC 61850 Process Bus Solution providing resource optimization and minimizing total P&C lifecycle costs
- Support for hybrid schemes. Harfiber in one end and traditional-wiring at the other end. Learn More
New and Enhanced IEC61850 services (FW version 5.90)
- New user-configurable buffered report control block
- Extended GOOSE subscription functionality, up to 16 remote devices
Security Enhancements - Enabling NERC CIP compliance:
- Dual Permission access requiring live permission from both the user and from SCADA operators before settings can be changed or commands can be given to the relay
- Logging of user commands in the security audit trail relay - creates a record and sequence of events for troubleshooting and security auditing
Ambient Temperature Monitoring:
- Provides alarms when the ambient temperature exceeds hot extreme
New and Enhanced Protection and Control Functionality (FW version 5.90)
- Remote voltage phasors enable Syncheck with remote terminals
- Added backup protection functions with sensitive reverse power element "32S"
- Added "over, under and rate of change of" frequency elements
- New Thermal overload element
- New Broken conductor Element
Protection & Control 
