7SR21 & 7SR22 Performance Specification
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3.2 50BF & 50BF-I4 Circuit Breaker Fail
3.2.1 Reference
Parameter Value
Is 50BF Setting 0.050, 0.055… 2.0 xIn
Is 50BF-I4 Setting 0.005, 0.01… 2.0 xIn
t
CBF1
Stage 1 Delay setting 20, 25… 60000ms
t
CBF2
Stage 2 Delay setting 20, 25… 60000ms
3.2.2 Operate and Reset Level
Attribute Value
I
op
Operate level
100 % Is, ± 5 % or ± 1% In
I
reset
Reset level
<100 % I
op
, ± 5 % or ± 1% In
Repeatability
± 1 %
Variation
-10 °C to +55 °C
£ 5 %
f
nom
- 3 Hz to f
nom
+ 2 Hz
£ 5 %
3.2.3 Operate and Reset Time
Attribute Value
t
basic
Element basic operate time < 20 ms
t
op
Stage 1
t
CBF1
, ± 1 % or ± 20 ms
Stage 2
t
CBF2
, ± 1 % or ± 20 ms
Repeatability
± 1 % or ± 20 ms
Overshoot < 2 x 20 ms
Disengaging time < 30 ms