| Protection function |
ANSI |
| Three-phase overcurrent protection INST,DT or IDMT - I> ... I>>>> |
50/51_1..._4 |
| Residual overcurrent protection INST, DT or IDMT - I0> ... I0>>>> |
50/51N(S)_1...4 |
| Harmonic overcurrent protection / inrush blocking INST, DT or IDMT - Ixh > ... Ixh >>>> |
50/51h/68h |
| Cold load pick-up block - CLPU |
68 |
| Current unbalance / broken conductor protection INST, DT or IDMT - I2 (I/I1)>...I2 (I/I1)>>>> |
46/46R/46L |
| Low or high-impedance restricted earth-fault / cable end differential protection - I0d> |
87N |
| Cable thermal overload protection - T > |
49F |
| Auto-reclose - 0 -> 1 (5 shots) |
79 |
| CT supervision - CTS |
|
| Switch onto fault logic -SOTF |
|
| Breaker failure protection - CBFP |
50BF/52BF |