4.2
Definite-Time Overcurrent Protection 50(N)
Operating Modes
Three-phase
Two-phase
Measuring Method
All elements
51Ns-3
Setting Ranges / Increments
Pickup current 50–1, 50–2 (phases) forI
Pickup current 50–3 (phases)
Pickup Current 50N–1, 50N–2
(ground)
Pickup Current 50N–3 (ground)
Time delays T
Dropout time delays 50 T DROP-OUT, 50N T
DROP-OUT
Times
Pickup times (without inrush restraint, with restraint + 1 period)
First harmonic, rms value
- for 2 x setting value
- for 10 x setting value
Instantaneous value
- for 2 x setting value
- for 10 x setting value
Dropout Times
First harmonic, rms value
Instantaneous value
Dropout Ratio
Dropout ratio for
- first harmonic, rms value
- instantaneous value
Tolerances
Pickup times
Time delays T
SIPROTEC, 7SK80, Manual
E50417-G1140-C344-A4, Release date 08.2010
Standard
Phases A and C
First harmonic, r.m.s. value (true RMS)
Additional instantaneous values
= 1 A 0.10 A to 35.00 A or ∞ (disabled)
Nom
for I
= 5 A 0.50 A to 175.00 A or ∞ (disabled)
Nom
for I
= 1 A 1.0 A to 35.00 A or ∞ (disabled)
Nom
for I
= 5 A 5.0 A to 175.00 A or ∞ (disabled)
Nom
for I
= 1 A 0.05 A to 35.00 A or ∞ (disabled)
Nom
for I
= 5 A 0.25 A to 175.00 A or ∞ (disabled)
Nom
for I
= 1 A 0.25 A to 35.00 A or ∞ (disabled)
Nom
for I
= 5 A 1.25 A to 175.00 A or ∞ (disabled)
Nom
0.00 s to 60.00 s or ∞ (disabled)
0.00 s to 60.00 s
approx. 30 ms
Approx. 20 ms
approx. 16 ms
approx. 16 ms
approx. 30 ms
approx. 40 ms
approx. 0,95 for I/I
approx. 0,90 for I/I
3 % of setting value or 15 mA at I
or 75 mA at I
1 % or 10 ms
4.2 Definite-Time Overcurrent Protection 50(N)
≥ 0.3
Nom
≥ 0.3
Nom
= 1 A
Nom
= 5 A
Nom
Technical Data
Increments 0.01 A
Increments 0.01 A
Increments 0.01 s
Increments 0.01 s
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