GE Multilin L30 Line Current Differential System


The L30 is a cost-effective line current differential protection relay intended for sub-transmission and medium voltage lines and cables providing reliable and secure operation even under the worst case power system conditions. The L30 provides secure high-speed fault detection and clearance suitable for three-pole tripping applications. The L30 supports inter-relay communications via direct fiber as well as standard RS422, G.703 and C37.94 telecommunication interfaces. The L30 also provides synchrophasor measurements over Ethernet per IEEE C37.118.

Key Benefits:

  • Proven current differential protection ensures secure high-speed tripping
  • Advanced 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
  • Increased sensitivity through dynamic charging current compensation and communication channel asymmetry compensation
  • Adaptive restraint characteristic provides excellent security against measurement errors including CT saturation
  • Phasor Measurement Unit (synchrophasor) according to IEEE® C37.118 (2011) and IEC® 61850-90-5 support
  • 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
Get A Quote On This Product For Your Project



  • Overhead 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
  • Applications requiring three-pole auto-reclosing and independent synchrocheck supervision


Key Features:

  • Line current differential with adaptive restraint
  • Stub bus protection
  • Breaker failure
  • Three-pole autoreclose
  • Underfrequency protection
  • Phase directional overcurrent, neutral directional with dual polarity criteria, broken conductor and thermal overload
  • Non-directional overcurrent: phase, neutral and negative sequence
  • Phase over/under voltage, negative sequence overvoltage
  • Two independent synchronism check elements



  • Complete IEC 61850 Process Bus solution providing resource optimization and minimizing total P & C life cycle costs
  • Three independent 100Mbps Ethernet ports enable purpose specific LAN support that eliminates latency effect of heavy traffic protocols on mission critical communication services
  • Embedded IEEE 1588 time synch protocol support eliminates dedicated IRIG-B wiring requirements for IEDs
  • Direct I/O secures high-speed exchange of binary data between URs
  • Increase network availability by reducing failover time to zero through IEC62439-3 “PRP” support
  • IEC 61850-9-2LE networked or IEC61850-9-2 Hardfiber process bus support
  • DNP 3.0 (serial & TCP/IP)
  • IEC 60870-5-103 and IEC 60870-5-104
  • Modbus RTU, Modbus TCP/IP
  • HTTP, TFTP, SFTP and MMS file transfer
  • Redundant SNTP and IEEE 1588 for time synchronization
  • PRP as per IEC 62439-3
  • IRC module that combines C37.92 multimode and direct connection singlemode
  • Supports Routable GOOSE (R-GOOSE)

Cyber Security:

  • Password Complexity
  • AAA Server Support (Radius)
  • Role Based Access Control (RBAC)
  • Event Recorder (Syslog for SEM)


Expanded Control:

  • Expanded Bay Controller Capabilities – providing a one box solution
  • Line differential with new in-zone power transformer function
  • Added backup protection functions with phase and neutral directional overcurrent
  • New thermal overload element
  • New broken conductor element
  • Neutral directional overcurrent with dual polarity criteria “67N”

You may also like…