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SEL-311L Line Current Differential Protection

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.

SEL-387L Line Current Differential Relay

Use SEL-387L Line Current Differential Relays for economical, easy-to-apply line protection.

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.