Directional Overcurrent Protection 67, 67N - Siemens 7SC80 Manual

4.4

Directional Overcurrent Protection 67, 67N

Overcurrent Elements
The same specifications and characteristics apply as for the non-directional overcurrent protection of the
elements
50-1, 50-2, 50-3, 51, 51-1, 51-2, 51-3, 51-4, 50N-1, 50N-2, 50N-3, 51N, 51N-1, 51N-2, 51N-3, 51N-4 (see
previous sections).
Determination of Direction
Moreover, the following data apply for determining the fault direction:
For Phase Faults
Type
Forward range
Rotation of the reference voltage V
Dropout difference
Directional sensitivity
For Ground Faults
Type
Forward range
Rotation of the reference voltage V
Dropout difference
Directional sensitivity
Type
Forward range
Rotation of the reference voltage V
Dropout difference
Directional sensitivity
Times
Pickup times (without inrush restraint, with inrush restraint + 1 cycle)
67-1, 67-2, 67-3 , 67N-1, 67N-2, 67N-3
- for setting value x 2
- for setting value x 10
SIPROTEC Compact, 7SC80, Manual
E50417-G1140-C486-A8, Edition 07.2017
with cross-polarized voltages;
with voltage memory (memory depth 2 seconds) for
measuring voltages that are too small
V ± 86°
ref,rot
–180° to +180°
ref,rot
increments 1°
3°
unlimited for 1-phase and 2-phase faults
for 3-phase faults dynamically unlimited, steadystate
approx. 7 V phase-to-phase
with zero-sequence system quantities 3V
V ± 86°
ref,dreh
–180° to +180°
ref,rot
increments 1°
3°
V ≈ 2.5 V displacement voltage, measured
E
3V ≈ 5 V displacement voltage, calculated
0
with negative-sequence system quantities 3V
V ± 86°
ref,dreh
–180° to +180°
ref,ror
increments 1°
3°
3V ≈ 5 V negative-sequence voltage
2
3Ι ≈ 45 mA negative-sequence current for Ι
2
3Ι ≈ 225 mA negative-sequence current for Ι
2
approx. 45 ms
approx. 40 ms
4.4 Directional Overcurrent Protection 67, 67N
0
Technical Data
, 3Ι
0
, 3Ι
2 2
= 1 A
Nom
= 5 A
Nom
527