Time Current Curves; Definite Time-Delay Trip Curve (Dt) - ABB PR521 Operator's Manual

10. Curve tempo corrente
10.1. Curva di intervento a tempo fisso (DT) per
protezione da sovracorrente
t [s]
100
10
1.6
1
0.1
0.01
0.2 0.3 0.4 0.5 0.6 0.8
0.7

10. Time current curves

10.1. Definite time-delay trip curve (DT) for over-
current protection
IEC 255-3
Definite Time Curve
K = 1.6
K = 0.1
1 2 3
0.9
t = K x 1
I >
7 8 10
4 6
5 9
647008/002 - 2000/05 it-en - 31/40
I/I>