Technical Data
10-18
7SJ63 Manual
C53000-G1140-C120-1
Figure 10-3 Trip Characteristics Of The Inverse-time Overcurrent Protection, As Per ANSI/IEEE (Phases And Ground)
DEFINITE INVERSE
D [s]
I
/
I
p
1
2
5
10
15
0.5
1
0.3
0.1
1
2
3
5
10
20
100
20
10
5
2
0.5
0.2
0.05
VERY INVERSE
EXTREMELY INVERSE
D [s]
t [s]
t [s]
I
/
I
p
I
/
I
p
1
2
5
10
15
0.5
D [s]
1
2
5
10
15
0.5
1
0.3
0.1
1
2
3
5
10
20
100
20
10
5
2
0.5
0.2
0.05
[s]
1
2
3
5
10
20
0.3
0.1
100
20
10
2
0.05
5
[s]
0.2
0.5
1
t [s]
3
t
3.922
I I
p
⁄
(
)
2
1
–
----------------------------
0.0982
+
D
⋅
=
t
5.64
I I
p
⁄
(
)
2
1
–
----------------------------
0.02434
+
D
⋅
=
t
0.4797
I I
p
⁄
(
)
1.5625
1
–
-------------------------------------------
0.21359
+
D
⋅
=
30
3
3
[s]
30
30
t =Trip time in seconds
D =Setting value of the time multiplier
I
=Fault Current
I
p
=Setting value of the pickup current
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