IEEE C37.243-2015

This guide presents practical line current differential schemes using digital communications. Operating principles, synchronization methods, channel requirements, current transformer (CT) requirements, external time reference requirements, backup considerations, testing considerations, and trouble shooting are included. It also provides specific guidelines for various application aspects including multi-terminal lines, series compensated lines, mutually coupled lines, line charging current, in-zone transformers and reactors,single-phase tripping and reclosing, as well as communications channel requirements.