VAMP 265 - Page 88

2.13 Inverse time operation
2 Protection functions
Technical description
88
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VM265.EN011
Example for Delay type "Moderately inverse (MI)":
k = 0.50
I = 4 pu
I
pickup
= 2 pu
A = 0.0515
B = 0.114
C = 0.02
9.11140.0
1
2
4
0515.0
50.0
02.0























t
The operation time in this example will be 1.9 seconds. The
same result can be read from Figure 2.13.1-8.
Figure 2.13.1-5 ANSI/IEEE long
time inverse delay
Figure 2.13.1-6 ANSI/IEEE long
time very inverse delay