The SEL-551 Overcurrent/Reclosing Relay replaces the many relays, control switches, and wiring required in traditional distribution substation protection and control panels. The relay also replaces line recloser control packages at a fraction of the cost.
Asset Protection—Monitor and protect distribution feeders, distribution buses, transformers, capacitors, or circuit breakers.
Current Transformer (CT) Connection Versatility—Connect the separate neutral-current input to accommodate core-balance CTs, separate neutral CTs, tertiary-winding CTs, or CT ground-residual circuits.
Reclosing Control—Coordinate with downstream reclosers using sequence coordination logic to program up to four reclosing attempts.
Field-Proven Ruggedness—Program SELogic control equation inputs and outputs to meet application needs in multiple environments. A wide operating temperature range (–40° to +85°C) allows installation in a control house or outdoor enclosure.