SEL-387/SEL-387A Current Differential and Overcurrent Relay

The SEL-387 Current Differential and Overcurrent Relay provides protection, control, and metering for transformers, machines, buses, breakers, and feeders. Features include four three-phase current inputs with independent restrained and unrestrained differential protection, programmable single- or dual slope differential characteristic, circuit breaker monitor, battery voltage monitor, and enhanced SELOGIC® Control Equations.

SEL-387E Current Differential and Voltage Relay

The SEL-387E Current Differential and Voltage Relay provides protection to two- or three-winding power transformers. Voltage inputs for power metering, overexcitation protection, and over-/underfrequency load shedding provide versatile solutions for power apparatus protection.

SEL-587 Current Differential Relay

The SEL-587 Current Differential / Overcurrent Relay provides protection for any two-input apparatus such as transformers, motors, generators, and reactors. Apply it for differential and overcurrent protection and use event reports for quick post-event analysis.

SEL-487B Bus Differential and Breaker Failure Relay

The SEL-487B provides optimized 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.

SEL-587Z High-Impedance Differential Relay

The SEL-587Z Relay is a flexible high-impedance differential relay that combines time-proven high-impedance analog technology with the advantages of microprocessor technology. Use event reports and Sequential Event Recorder (SER) for quick post-event analysis.