AQ-T259 Transformer Protection IED

AQ-T259 is a 3-winding transformer protection IED with differential protection function and integrated AVR function. The AQ-T259 communicates using various protocols including IEC 61850 substation communication standard.

Highlights

  • 3-winding transformer protection
  • Freely programmable harmonic restraint function
  • Integrated AVR
Protection
3-winding transformer differential (87T)
High/low impedance restricted earth fault / cable end differential * (87N1, 87N2)
Transformer thermal overload (49T/49RTD)
Three-phase overcurrent, 2+2 stages INST, DT or IDMT (50/51)
Earth-fault (sensitive), 3 stages INST, DT or IDMT (50/51N)
Harmonic overcurrent / inrush blocking, 4 stages INST, DT or IDMT (50/51H, 68)
Current unbalance / broken conductor, 2+2 stages INST, DT or IDMT (46/46R/46L)
Directional overcurrent, 4 stages INST, DT or IDMT (67)
Directional (sensitive) earth-fault, 4 stages INST, DT or IDMT (67N)
Overvoltage, 2 stages INST, DT or IDMT (59)
Undervoltage, 2 stages INST, DT or IDMT (27)
Zero sequence overvoltage, 2 stages INST, DT or IDMT (59N)
Positive/Negative sequence overvoltage, 2 stages INST, DT or IDMT (59N/47)
Over/under frequency, 4 stages INST or DT (81O/81U)
Rate of change of frequency, 4 stages INST or DT or IDMT (81R)
Volts per hertz (24)
Breaker failure protection (50BF/52BF)
Arc protection (option) (50ARC/50NARC)