Multi-application relay for power systems

摘要

A microprocessor-based multifunction overcurrent relay for protecting power systems has a plurality of overcurrent elements implemented in a software program. Sufficient overcurrent elements are provided to accomplish a selected one of three independent applications, including feeder protection, motor protection, or breaker failure protection. The relay includes elements for selecting one application by the user from the three possible applications and produces output signals when an overcurrent condition is determined.