ABB REF 610 Technical Reference Manual page 39

1MRS 755310 Feeder Protection Relay
Technical Reference Manual
t/s
700
600
500
400
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100
90
80
70
60
50
40
30
20
10
9
8
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5
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1
0.9
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1 2
Fig. 4.1.4.9.-4 Long-time inverse-time characteristic
3 4 5 6 7 8 910
REF 610
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>
39