| ANSI |
IEC 60617 |
Description |
| 21FL |
FLOC |
Fault locator |
| 21G |
Z< |
Three-phase underimpedance protection, low-set stage |
| 24 |
U/f> |
Overexcitation, low-set stage |
| 24 |
U/f>> |
Overexcitation, high-set stage |
| 25 |
SYNC |
Synchro-check/ voltage check, stage 1 |
| 25 |
SYNC |
Synchro-check/ voltage check, stage 2 |
| 27 |
3U< |
Three-phase undervoltage, low-set stage |
| 27 |
3U<< |
Three-phase undervoltage, high-set stage |
| 27, 47, 59 |
U1< U2> U1> |
Phase-sequence voltage protection, stage 1 |
| 27, 47, 59 |
U1< U2> U1> |
Phase-sequence voltage protection, stage 2 |
| 32 |
P← |
Three-phase underpower or reverse power, stage 1 |
| 32 |
P← |
Three-phase underpower or reverse power, stage 2 |
| 32 |
P← |
Three-phase underpower or reverse power, stage 3 |
| 32P/32Q |
P>→/Q>→ |
Three-phase directional overpower, stage 1 |
| 32P/32Q |
P>→/Q>→ |
Three-phase directional overpower, stage 2 |
| 32P/32Q |
P>→/Q>→ |
Three-phase directional overpower, stage 3 |
| 37 |
3I< |
Three-phase non-directional undercurrent, stage 1 |
| 37 |
3I< |
Three-phase non-directional undercurrent, stage 1 |
| 37 |
3I< |
Three-phase non-directional undercurrent, stage 2 |
| 40 |
X< |
Three-phase underexcitation protection, low-set stage |
| 40 |
X<< |
Three-phase underexcitation protection, high-set stage |
| 46 |
I2> |
Negative-phase sequence, low-set stage |
| 46 |
I2>> |
Negative-phase sequence, high-set stage |
| 46 |
ΔI> |
Phase discontinuity |
| 46R |
|
Phase reversal protection |
| 48, 14, 66 |
Is²t, n< |
Three-phase start-up supervision for motors (incl. I2t and speed device modes, and start-up counter) |
| 49F |
3Ith> |
Three-phase thermal protection for cables |
| 49M/49G/49T |
 |
Three-phase thermal protection for devices (motors, generators and transformers) |
| 50N |
I0>>> |
Non-directional earth-fault, instantaneous stage |
| 50N/51N |
I0>> |
Non-directional earth-fault, high-set stage |
| 50P/51P |
3I>>> |
Three-phase non-directional overcurrent, instantaneous stage |
| 51 |
3I> |
Three-phase non-directional overcurrent, low-set stage |
| 51C, 37C, 68C |
3I> 3I< |
Three-phase overload protection for shunt capacitor banks |
| 51N |
I0>/SEF |
Non-directional earth-fault, low-set stage (or SEF=sensitive earth-fault protection) |
| 51NC |
3ΔI> |
Three-phase current unbalance protection for H-bridge connected shunt capacitor banks |
| 51NC |
ΔI> |
Current unbalance protection for shunt capacitor banks |
| 51P-1 |
3I> |
Three-phase non-directional overcurrent, low-set stage |
| 51V |
I(U)> |
Voltage-dependent overcurrent, low-set stage |
| 51V |
I(U)>> |
Voltage-dependent overcurrent, high-set stage |
| 551P-2 |
3I>> |
Three-phase non-directional overcurrent, high-set stage |
| 59 |
3U> |
Three-phase overvoltage, low-set stage |
| 59 |
3U>> |
Three-phase overvoltage, high-set stage |
| 59N |
U0> |
Residual overvoltage, low-set stage |
| 59N |
U0>> |
Residual overvoltage, High-set stage |
| 59N |
U0>>> |
Residual overvoltage, instantaneous stage |
| 60 |
FUSEF |
Fuse failure supervision |
| 67-1 |
3I>→ |
Three-phase directional o/c, low-set stage |
| 67-2 |
3I>>→ |
Three-phase directional o/c, high-set stage |
| 67 |
3I>>>→ |
Three-phase directional o/c, instantaneous stage |
| 67N |
I0>>>→ |
Directional earth-fault, instantaneous stage |
| 67N |
I0>>→ |
Directional earth-fault, high-set stage |
| 67N |
I0>→ |
Directional earth-fault, low-set stage |
| 67N/51N |
I0>→ /SEF |
Directional earth-fault, low-set stage (or SEF=sensitive earth-fault protection) |
| 68 |
3I2f> |
Three-phase transformer inrush and motor start-up current detector |
| 79 |
0 → 1 |
Auto-reclosure |
| 81U/81O |
f, df/dt |
Underfrequency or overfrequency, stage 1 (incl. rate of change) |
| 87G |
3DI> |
Stabilized three-phase differential protection for generators |
| 87G/87M |
3DI> |
High-impedance or flux-balance based differential protection for generators and motors |
| 87N |
ΔI0>, REF |
High-impedance based restricted earth-fault |
| 87T |
3ΔI>, 3ΔI>> |
Stabilized three-phase differential protection for transformers |
| 87TN |
ΔI0> |
Stabilized restricted earth-fault, stage A |