Functions

• Differential protection

– Transformer differential protection, two winding (PDIF, 87T)

– Transformer differential protection, three winding (PDIF, 87T)

– Restricted earth fault protection (PDIF, 87N)

– High impedance differential protection (PDIF, 87X)

• 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, two time constants (PTTR, 49)

– Breaker failure protection (RBRF, 50BF)

– Pole discordance protection (RPLD, 52PD)