ABB PR521 - Very Inverse (VI) Time-Delay Curve; VI Curve for Over-Current Protection

647008/002 - 2000/05 it-en - 33/40
10.3.Curva di intervento a tempo molto inverso (VI)
per protezione da sovracorrente
10.3.Very inverse time-delay trip curve (VI) for
over-current protection
100
10
1
0.1
0.01
2
1.3
3456
7
8
9
10 20 30 40
50
60
I/I>
t [s]
IEC 255-3
Very Inverse Curve
I
>
K = 1.6K = 1.6
K = 0.1K = 0.1
13.5
t = K x
-1
I
I>
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