Breaker Failure Protection 50Bf - Siemens 7SK80 Manual

4.18

Breaker Failure Protection 50BF

Setting Ranges / Increments
Pickup threshold 50-1 BF
Pickup threshold 50N-1 BF
Time delay 50 BF trip timer
Times
Pickup times
- for internal start
- for external start
Dropout time
Dropout ratio
Tolerances
Pickup threshold 50-1 BF, 50N-1 BF
Time delay 50 BF trip timer
Influencing Variables for Pickup Values
Auxiliary DC voltage in range 0.8 ≤ V
Temperature in range
–5 °C (41 °F) ≤ Θ
Frequency in range 0.95 ≤ f/f
Harmonics
- up to 10 % 3rd harmonic
- up to 10 % 5th harmonic
1)
A further delay for the current may be caused by compensation in the secondary CT circuit.
SIPROTEC, 7SK80, Manual
E50417-G1140-C344-A5, Release date 11.2012
for I
Nom
for I
Nom
for I
Nom
for I
Nom
/V
Aux AuxNom
≤ 55 °C (131 °F)
amb
≤ 1.05
Nom
= 1 A 0.05 A to 20.00 A
= 5 A 0.25 A to 100.00 A
= 1 A 0.05 A to 20.00 A
= 5 A 0.25 A to 100.00 A
0.06 s to 60.00 s or ∞
Included in time delay
Included in time delay
approx. 25 ms
= 0,95 (minimal hysteresis between pickup and
tripping ≥ 32,5 mA)
3 % of setting value,
or 15 mA for I
or 75 mA for I
1 % or 20 ms
≤ 1.15
1 %
0.5 %/10 K
1 %
1 %
1 %
Technical Data
4.18 Breaker Failure Protection 50BF
Increments 0.01 A
Increments 0.01 A
Increments 0.01 s
= 1 A
Nom
= 5 A
Nom
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