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Feeder Protection Relay

The SEL-751A Feeder Protection Relay is the right solution for industrial and utility feeder protection, with flexible I/O options, easy mounting, and fast settings.

The SEL-751A provides complete feeder protection, with overcurrent, overvoltage, undervoltage, and frequency elements. Easily upgrade protection without cutting or drilling existing cutouts with a small form factor and multiple mounting adapters. Quickly integrate into serial- or Ethernet-based communications with IEC 61850, Mirrored Bits communications, and other protocols.

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Feeder Protection—Protect radial and looped distribution circuits with comprehensive protection capabilities, including time-overcurrent, autoreclosing, over-/undervoltage, frequency, and much more.

Arc-Flash Mitigation—Improve safety for personnel with optional arc-flash detection capabilities. The SEL-751A offers combined light and high-speed overcurrent detection for arc-flash events. This combination provides the ideal solution for speed and security.

Automation and Control—Apply the SEL-751A on feeders and provide protection, automation, and control capabilities all in one package. SELogic control equations support many automated applications without the need for additional automation controllers. The configurable front-panel buttons can replace conventional panel controls and simplify overall applications and wiring.

Event Analysis—Conduct post event analysis more efficiently with the detailed event records that are available in the SEL-751A. Combine oscillographic and digital information to find root cause. Add a satellite-synchronized time source, like the SEL-2401 or SEL-2407 Satellite-Synchronized Clocks, for convenient alignment of event information from multiple devices.

Situational Awareness—Improve situational awareness and asset utilization with IEEE C37.118 synchrophasor measurement. Aggregate synchrophasor information from across your system to understand system trends, make decisions based on state measurement rather than state estimation, and aid in post event analysis.

Reliable in Harsh Environments—Rely on the SEL-751A for protection and control applications, even in harsh and hazardous environments. The SEL-751A is designed and tested to meet and exceed utility and industrial requirements. An operating temperature range of –40° to +85°C (–40° to +185°F), Class 1, Zone 2 approval, and optional conformal coating mean this relay will provide years of reliable service.

  • Customize front-panel pushbutton operation and LEDs, or use default breaker trip/close functions.
  • Personalize LCD messages using event-driven display point settings.
  • Create an integrated control system with a variety of I/O and communications options.
  • Use the programmable control logic and integration features with a communications link for control and protection of remote substations.
  • Use comprehensive reporting to understand events, schedule maintenance, detect unfavorable trends, modify loads, and satisfy information requirements of supervisory systems.
  • Include resistance temperature detector (RTD) inputs as part of system integration or to bias protection.
  • Remediate arc-flash hazards with arc-flash detection.
  • Analyze overcurrent protection system performance using the built-in Sequential Events Recorder (SER).
  • Use acSELerator QuickSet SEL-5030 or SEL-5010 Relay Assistant Software to manage your relay settings.
  • Install protection where it is needed without special enclosures or ventilation systems. Class 1, Division 2 certification allows the SEL-751A in locations that may be adjacent to hazardous gasses, vapors, or liquids.




Reduce Arc-Flash Hazards

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Reduce Arc-Flash Hazards

Complete Feeder Protection
Maximize control scheme flexibility using time- and instantaneous-overcurrent, overvoltage, undervoltage, and frequency elements with breaker failure protection for one three-pole breaker.

Optional Protection Features
Use the SEL-751A with one of the voltage input options to provide over- and underfrequency, rate-of-change-of-frequency, and over- and undervoltage protection as well as synchronism check, dc station battery monitoring, arc-flash detection, and power and demand metering.

Convenient Controls
Use the four programmable pushbuttons on the front panel for quick, personalized control.

Easy Communications
Choose from Ethernet or serial communications and several protocols, including Mirrored Bits communications and IEC 61850. Pick multiple sessions of Modbus TCP, Modbus Serial, DNP3 LAN/WAN, or DNP3 serial for custom configuration of your applications.

Expanded SELogic Control Equations
Use math and logic combinations of analog and digital values for customized applications. Adapt system control based on prefault conditions. Scale analog values and latch momentary inputs for SCADA retrieval.

Reclosing Control
Match various reclosing practices using the programmable four-shot recloser with optional synchronism check.

Rugged Design
Rely on the industry’s widest ambient temperature operating range, –40° to +85°C (–40° to +185°F).

Automatic Notification
Alert key personnel to problems automatically with direct SEL-3010 Event Messenger support.

Easy Installation
Easily install into existing locations using available retrofit kits and mounting adapters, with no cutting or drilling.

Flexible Design
Choose from many installation and integration options with a small form factor and slide-in expansion cards.

Flexible I/O for Local Control and System Applications
The base system includes three digital outputs and two digital inputs. There are three card slots for optional SELect I/O cards, including the following:

  • Four arc-flash sensor inputs
  • Four digital inputs (DI) and four digital outputs (DO)
  • Four DI and four fast, high-current interrupting DO
  • Four DO, three DI, and one analog output (AO)
  • Four analog inputs (AI) and four AO
  • Eight AI for dc process values
  • Eight DI
  • Three ac voltage inputs
  • Ten RTD inputs

Integrated Communications
The SEL-751A offers many communications media and protocol options. Versatile communications options provide fast integration into both new and existing applications.

  • Communications Media
    • Ethernet 10/100BASE-T
    • Ethernet 100BASE-FX
    • Single or dual Ethernet ports
    • EIA-232 serial
    • EIA-485 serial
    • Fiber-optic serial multimode ST
  • Communications Protocols
    • Mirrored Bits communications
    • IEC 61850
    • DNP3 LAN/WAN
    • DNP3 Serial
    • Modbus TCP
    • Modbus RTU
    • Telnet
    • FTP
    • IEEE C37.118 Synchrophasors
Retrofit Replacement Kits
Replace existing feeder protection with the SEL-751A and the applicable mounting kits. These kits provide the parts needed to easily replace many older feeder relays with the SEL-751A.

Find other mounting options with the SEL Mounting Selector.

Conformal Coating
Protect equipment from harsh environments and airborne contaminants such as hydrogen sulfide, chlorine, salt, and moisture.
Learn more about conformal coating.


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SELect Input Output Card Installation Instructions


Minimum QuickSet Version

Product Revision Z Number Minimum Software Version
SEL-751A R419 011
Please contact Application Engineer for firmware related to your hardware platform.  The current revision does not apply to all hardware.

Minimum QuickSet Version

Product Revision Z Number Minimum Software Version
SEL-751A R419 011
Please contact Application Engineer for firmware related to your hardware platform.  The current revision does not apply to all hardware.

Product Certifications