ABB REF 610 Technical Reference Manual page 36

REF 610
36
Feeder Protection Relay
Technical Reference Manual
t/s
70
60
50
40
30
20
10
9
8
7
6
5
4
3
2
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
1 2
Fig. 4.1.4.9.-1 Normal inverse-time characteristic
3 4 5 6 7 8 910
1MRS 755310
k
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.05
20 I/I>