2.24 Inverse time operation
2 Protection functions
Technical description
140
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Example for Delay type "Moderately inverse (MI)":
k
= 0.50
I
= 4 pu
I
pickup
= 2 pu
A
= 0.1735
B
= 0.6791
C
= 0.8
D
= -0.08
E
= 0.127
38
.
0
8
.
0
2
4
127
.
0
8
.
0
2
4
08
.
0
8
.
0
2
4
6791
.
0
1735
.
0
5
.
0
3
2
t
The operation time in this example will be 0.38 seconds. The
same result can be read from Figure 2.24.1-11.
Figure 2.24.1-11 IEEE2 moderately
inverse delay
Figure 2.24.1-12 IEEE2 normal
inverse delay