27
1
2
3
4
5
10
20
6
7 8 9
I/I>
0.05
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
k
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
2
3
4
5
6
7
8
9
10
20
30
40
50
60
70
80
90
100
200
300
400
500
600
700
t/s
Fig. 11. Inverse-time characteristics of overcurrent and earth-fault relay module SPCJ 4D28
Long-time inverse