Functions

• Differential protection

– High impedance differential protection(PDIF, 87X)

• Line differential protection

– Line differential protection, 3 CT sets, 2-3 line ends (PDIF, 87L)

– Line differential protection, 6 CT sets, 3-5 line ends (PDIF, 87L)

– Line differential protection 3 CT sets, with in-zone transformers, 2-3 line ends (PDIF, 87LT)

– Line differential protection 6 CT sets, with in-zone transformers, 3-5 line ends (PDIF, 87LT)

• Distance protection

– Distance protection zones (PDIS, 21)

– Phase selection with load encroachment (PDIS, 21)

– Power swing detection (RPSB, 78)

– Automatic switch onto fault logic (PSOF)

• Current protection

– Instantaneous phase overcurrent protection (PIOC, 50)

– Four step phase overcurrent protection (POCM, 51/67)

– Instantaneous residual overcurrent protection (PIOC, 50N)

– Four step residual overcurrent protection (PEFM, 51N/67N)

– Thermal overload protection, one time constant (PTTR, 26)

– Breaker failure protection (RBRF, 50BF)

– Stub protection (PTOC, 50STB)

– Pole discordance protection (RPLD, 52PD)