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Line Current Differential Protection and Automation System

Use the SEL-311L Line Current Differential Relay with integral four-zone distance backup for easy-to-apply, high-speed line protection.

Apply subcycle current differential protection with included four-zone distance and directional overcurrent backup. Use single or dual differential channels for reliability. Apply the SEL-311L on two- or three-terminal lines. Unique measuring elements provide coordination with tapped loads. Reduce total project construction and operation costs through integration of the included four-shot recloser and relay logic operators into your automation system.

Improve protection system reliability with continuous checks of communications quality, breaker wear, battery voltage, and relay health. Use the included LCD display in place of traditional panel meters.

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Line Current Differential Protection—Apply single- or three-pole subcycle differential protection. A vector ratio of the local and remote phase and sequence currents provides high-speed protection independent of line loading, CT saturation, or tapped load. Use a true hot-standby differential channel for increased dependability and security. Loss of the primary channel does not cause loss of protection.

Distance and Overcurrent Backup—Enable up to four zones of phase and ground mho distance elements plus four zones of ground quadrilateral distance elements. Distance protection plus directional and nondirectional overcurrent elements provide a full backup protection system. Apply distance and overcurrent functions in communications-assisted and stepped-distance schemes.

Direct Fiber or Multiplexed Communications—Provide reliability and security with one or two differential communications channels. Select from ITU-T G.703 or EIA-422 electronic interfaces, IEEE C37.94, 1300 nm single-or multimode optical fiber, or 1550 nm single-mode optical fiber. The Alpha Plane restraint characteristic accommodates channel asymmetry and switching without loss of security or sensitivity.

Three-Terminal and Tapped Lines—Accommodate three-terminal lines, even with weak infeed. Tapped line settings make maximum use of communications for secure protection.



Secure Line Differential Protection
Sensitive differential elements provide subcycle operating time. Restraint for external faults uses an easy-to-set vector ratio of remote and local currents.

Synchrophasor Measurements
Turn state estimation into state measurement with wide-area measurement of voltage and current phase angles and magnitudes. Improve system stability with high-speed, load-angle measurements. Increase stable loading with analysis of voltage and angular stability.

Complete Line Protection
Protect transmission lines using differential and a combination of four stepped-distance zones of phase and ground-distance elements in communications-assisted schemes, with directional overcurrent element backup protection. Patented Capacitance Voltage Transformer (CVT) transient overreach logic enhances security of Zone 1 distance elements. Best Choice Ground Directional Element logic optimizes directional element performance and requires no directional settings.

Single-Pole Tripping
Use the optional single-pole tripping capability of the differential elements to improve system stability.

Built-In Web Server
Access basic relay information on a standard Ethernet network with a built-in web server. View relay status, Sequential Events Recorder (SER), metering information, and settings through easy access within a local network. Web server access requires relay password and is limited to read-only viewing of information.

Monitoring and Metering
Event reports, SER, circuit breaker contact wear monitor, substation battery monitor, instantaneous and demand metering, and local display panel.

Programmable four-shot breaker autoreclose with synchronism and voltage check logic for optimal system restoration.

Choose from four different channel types for differential communications:
- ITU-T G.703 codirectional to multiplexer
- EIA-422 56/64 Kbps
- IEEE C37.94 fiber-optic
- 1300 nm single-mode, fiber-optic

EIA-232 and EIA-485 serial ports for local/remote access and system integration.

Mirrored Bits communications protocol for eight channels of secure relay-to-relay logic communications available on both rear-panel EIA-232 serial ports. Download event reports using the optional Ethernet port. Quickly move information with IEC 61850 protocol, which includes a Select-Before-Operate function for added operational security. Increase communications dependability with dual failover Ethernet.

acSELerator QuickSet SEL-5030 Software
Helps speed relay application by allowing you to develop relay settings offline, program SELogic control equations, and analyze postfault event reports.

  • Single-Pole Tripping
  • Vertical panel-mount hardware package
  • Horizontal panel-mount hardware package
  • DNP3 Level 2 Outstation communications protocol
  • Conformal Coating: Protect equipment from harsh environments and airborne contaminants, such as hydrogen sulfide, chlorine, salt, and moisture.

Minimum Software Version

Latest Firmware Versions

There are no firmware versions available for this product.

Product Revision Firmware ID Date Available Serial Number
SEL-311L-0 R302 SEL-311L-0-R302-V0-Z011005-D20191215 9/3/20 ~1202470001

Serialnumber greater than or equal to 1143510001

SEL-311L-0 R164 SEL-311L-0-R164-V0-Z011005-D20191215 9/3/20 ~1202470001

Serialnumber less than 1143510001

SEL-311L-1 R502 SEL-311L-1-R502-V0-Z106006-D20141106 12/17/14 ~1143510001
Without Ethernet card and serial number greater than or equal to 1143510001
SEL-311L-1 R502 SEL-311L-1-R502-V0-Z106006-D20141106 12/17/14 ~1143510001
With Ethernet card. Serial number greater than or equal to 1143510001 or hardware originally shipped with R4xx firmware
SEL-311L-1 R215 SEL-311L-1-R215-V0-Z011005-D20130307 4/27/13 1131170001
Without E3 card and hardware originally shipped with R2xx firmware
SEL-311L-6 R302 SEL-311L-6-R302-V0-Z011005-D20191215 9/3/20 ~1202470001

Serialnumber greater than or equal to 1143510001

SEL-311L-6 R164 SEL-311L-6-R164-V0-Z011005-D20191215 9/3/20 ~1202470001

Serialnumber less than 1143510001

SEL-311L-7 R502 SEL-311L-7-R502-V0-Z106006-D20141106 12/17/14 ~1143510001
Without E3 card and serial number greater than or equal to 1143510001
SEL-311L-7 R502 SEL-311L-7-R502-V0-Z106006-D20141106 12/17/14 ~1143510001
With E3 Card. Serial number greater than or equal to 1143510001 or hardware originally shipped with R4xx firmware
SEL-311L-7 R215 SEL-311L-7-R215-V0-Z011005-D20130307 4/27/13 1131170001
Without E3 card and hardware originally shipped with R2xx firmware
SEL-E3 Card R114-V0 SEL-E3-R114-V0-Z001001-D20190111 3/26/19 ~1190850001

The Firmware IDs for older versions of the firmware can typically be found in Appendix A of the instruction manual.

Minimum Software Version

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3xx Software Tab

Configuration Software

acSELerator QuickSet SEL-5030 Software

QuickSet is a tool for engineers and technicians to quickly and easily configure, commission, and manage power system devices. QuickSet includes a Graphical Logic Editor and a device template tool to reduce configuration time and streamline deployment.

Learn more and download on the QuickSet software page.

acSELerator Architect SEL-5032 Software

Architect allows users to configure and document IEC 61850 systems that include GOOSE, Sampled Values (SV), or Manufacturing Message Specification (MMS) communications. Architect automatically compares SCL files with IEC 61850 requirements to ensure standard compliance.

Learn more and download on the Architect software page.

Automated Data Collection

SEL Data Management and Automation (DMA) Application Suite

Available on the Blueframe platform, DMA applications automatically collect, store, and manage device-specific information like oscillography, Sequence of Events (SOE) data, device settings, and property information. They also provide automated password rotation and streamlined device audits.

Learn more on the DMA software page.

Visualization and Analysis

SEL-5601-2 synchroWAVe Event Software

synchroWAVe Event helps engineers diagnose a protective relay’s behavior during a power system fault. It is a powerful and easy-to-use solution for displaying and analyzing SEL relay event reports and COMTRADE files.

Learn more and download on the synchroWAVe Event software page.

Product Certifications