Directional Overcurrent Protection - Siemens SIPROTEC 4 Manual

Technical Data

4.4 Directional Overcurrent Protection

4.4 Directional Overcurrent Protection
Time Overcurrent Elements
The same specifications and characteristics apply as for non-directional time overcurrent protection (see
previous Sections).
Determination of Direction
Moreover, the following data apply to direction determination:
For Phase Faults
Polarization
Forward Range
Rotation of the reference voltage V
Dropout difference
Directional sensitivity
For Ground Faults
Polarization
Forward Range
Rotation of the reference voltage V
Dropout difference
Directional Sensitivity
Polarization
Forward Range
Rotation of the reference voltage V
Dropout difference
Directional Sensitivity
Times
Pickup times (without inrush restraint, with restraint + 1 period)
50-1, 50-2, 50-3, 50N-1, 50N-2, 50N-3
- for 2 x setting value
- for 10 x setting value
376
With cross-polarized voltages;
with voltage memory 2 s
V ± 86°
ref,rot
–180° to +180°
ref,rot
Increments 1°
3°
Unlimited for single and two phase faults
For three phase faults, dynamically unlimited, steady-
state
approx. 7V phase-to-phase
with zero sequence quantities 3V
V ± 86°
ref,rot
–180° to +180°
ref,ot
Increments 1°
3°
V ≈ 2.5 V displacement voltage, measured
N
3V ≈ 5 V displacement voltage, calculated
0
with negative sequence quantities 3V
V ± 86°
ref,rot
–180° to +180°
ref,rot
Increments 1°
3°
3V ≈ 5 V negative sequence voltage
2
3Ι ≈ 45 mA negative sequence current with Ι
2
3Ι ≈ 225 mA negative sequence current with Ι
2
5 A
approx. 45 ms
approx. 40 ms
, 3Ι
0 0
, 3Ι
2 2
SIPROTEC 4, 7SJ80, Manual
E50417-G1140-C343-A8, Edition 12.2017
= 1 A
Nom
=
Nom