The SEL-351 Protection System has built-in Ethernet and IEEE C37.118 synchrophasors and is ideal for directional overcurrent applications. Optional MIRRORED BITS communications and power quality monitoring add flexibility to solutions. The SEL-351 is the protection standard for utility and industrial electrical systems around the world.

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The SEL-451 is a complete standalone system. It has the speed, power, and flexibility to combine complete substation bay control with high-speed breaker protection in one economical system. You can use the SEL-451 as an integral part of a full substation protection, control, and monitoring solution. It reduces maintenance costs by accurately tracking the breaker operation. By monitoring breaker interruption times and the accumulated breaker duty, the SEL-451 helps you easily determine the need for proactive maintenance. You can integrate information with SCADA or automation systems through a communications processor or directly to the Ethernet port. Optional Time-Domain Link (TiDL) technology and SEL Sampled Values (SV) technology using IEC 61850-9-2 transform the way you modernize your substation.

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The SEL-487B provides optimized, low-impedance bus differential fault detection by using high-speed, subcycle protection coupled with high-security operation for external faults. Superior protection performance is combined with integrated station automation features for seamless transition into new and retrofit applications. Optional Time-Domain Link (TiDL) technology and SEL Sampled Values (SV) technology using IEC 61850-9-2 transform the way you modernize your substation.

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Protect and monitor transformers with the powerful SEL-487E. It offers up to five three-phase restraint inputs, three independent restricted earth fault (REF) protection elements, and two three-phase voltage inputs, all with synchrophasors. The SEL-487E limits transformer damage by responding to internal fault conditions in less than 1.5 cycles. The relay also helps avoid catastrophic transformer failure by detecting turn-to-turn faults involving as little as 2 percent of the total winding. The SEL-487E includes optional distance elements to provide transformer or line protection. You can minimize commissioning time and eliminate costly errors with included software that recommends matrix compensation settings. Through-fault and thermal monitoring allow you to track transformer wear and schedule maintenance as necessary. Breaker wear monitoring reduces inefficient and costly breaker maintenance, saving time and money. Optional Time-Domain Link (TiDL) technology and SEL Sampled Values (SV) technology using IEC 61850-9-2 transform the way you modernize your substation.

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The SEL-587Z High-Impedance Differential Relay is an economical and flexible relay that combines time-proven, high-impedance analog technology with the advantages of microprocessor technology. Use event reports and the Sequential Events Recorder (SER) for quick postevent analysis.

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The SEL-387A Current Differential and Overcurrent Relay offers restrained and unrestrained differential protection for two terminals. Second-, fourth-, and fifth-harmonic elements, augmented by the dc element, provide security during transformer energization and overexcitation conditions in a user-defined choice of either harmonic restraint or harmonic blocking. Overcurrent elements provide backup protection that contributes to the versatility of the SEL-387A.

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The SEL-400G offers primary and backup protection for generators of all sizes and types, including hydro, pumped-storage hydro, steam turbine, and combustion gas turbine generators. It combines generator, bus, and step-up transformer protection in one package, making the relay an economical solution for an entire generation unit.

Advanced protection functions, like transverse differential protection, provide turn-to-turn fault detection, which allows for earlier fault detection, limits damage to your generator, and helps you return to service faster. Adaptive differential protection and a wide frequency tracking range (5–120 Hz) improve protection security. Dual frequency zones and autosynchronization offer smooth synchronization to the grid.

You can quickly integrate the SEL-400G into serial- or Ethernet-based communications. The new SEL Grid Configurator software allows you to quickly create, manage, and deploy device settings. Or you can continue to use ACSELERATOR QuickSet SEL-5030 Software for your configuration needs.

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Provide proven primary and backup protection for utility and industrial generators to IEEE turbine protection standards.

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The SEL-700G is the right solution for utility and industrial generator protection, with an autosynchronizer, flexible I/O, and advanced communications. It provides a complete protection and synchronization solution for synchronous generators, so you can eliminate the complexity and cost of standalone synchronizer packages. Integrating the synchronization capability into the generator protection relay provides the most cost-effective and reliable solution.

The 5-inch, 800 x 480 color touchscreen display option allows you to directly set, monitor, and control your system, including up to five two- or three-position disconnect switches. A small form factor and multiple mounting adapters make it easy to upgrade protection without cutting or drilling existing cutouts. You can quickly integrate the SEL-700G into serial- or Ethernet-based communications with IEC 61850 Edition 2, EtherNet/IP, the IEEE 1588 Precision Time Protocol (PTP), IEC 60870-5-103, the IEC 62439 Parallel Redundancy Protocol (PRP), MIRRORED BITS communications, Modbus, DNP3, and other protocols.

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Protect asynchronous (induction) and synchronous motors with one SEL-710-5 Motor Protection Relay. Features include broken rotor bar detection and variable-frequency drive (VFD) support as well as options for arc-flash detection (AFD), differential protection, and synchronous motor protection. The synchronous option supports power factor regulation and includes, at no additional cost, a voltage divider accessory to interface with the motor excitation system.

An optional 5-inch, 800 × 480 color touchscreen display allows you to directly set, monitor and control your system, including up to five two- or three-position disconnect switches. You can quickly integrate the SEL-710-5 into serial-or Ethernet-based communications schemes with IEC 61850 Edition 2, IEC 60870-5-103, the IEC 62439 Parallel Redundancy Protocol (PRP), MIRRORED BITS communications, Modbus, DNP3, EtherNet/IP, the IEEE 1588 Precision Time Protocol (PTP), and other protocols. Together with the industry’s best AccuTrack Thermal Model, these features provide a great solution for all of your motor protection applications.

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