SEL551/SEL-551C Overcurrent/Reclosing Relay
The SEL-551C Relay provides overcurrent relay users with new flexibility in distribution system protection. The SEL-551C provides six inputs and three outputs, with up to two communications ports, for more control options. The SELOGIC®control equations have added rising and falling edge triggers and latches for custom logic applications.
Front- and Rear-Panel Diagrams
Complete Overcurrent Protection
Protect lines and equipment using a sensitive and secure mix of phase, negative-sequence, and ground overcurrent elements. Have complete ground fault protection with residual ground and neutral ground overcurrent elements. Provide high-speed operation, even with severe CT saturation, using the SEL Adaptive Overcurrent Element.
Multishot Reclosing With Sequence Coordination
Program up to a four-shot reclose sequence with reclose initiate supervision, skip-shot sequencing, and stall-open interval timing.
Integrate into industrial protection and control schemes with Modbus® RTU protocol. Order the serial communications port as either EIA-232 or EIA-485.
Field-Proven With Robust I/O
Program the two inputs and five outputs to meet your application needs using SELogic® control equations. A wide operating temperature range (—40° to +85°C) allows for installation in a control building or outdoor enclosure. Hardware options of high-current interrupting output contacts and plug-in connectors provide high reliability and
ease of installation/removal.
Programmable Logic and Local/Remote Controls
Use acSELErator® QuickSet™ SEL-5030 Software to configure traditional or advanced protection and control schemes. Quickly make logic changes or improvements without rewiring. Use the front panel or serial port to actuate separate control switches.