APPENDIX
361
NVA100X-D - Manual - 02 - 2016
Phase overcurrent 50/51 side H and side L - I
2
t inverse curves (I2t=K)
—
F_67-I2t-Char.ai
1.1
2
3
4
5
6
7
8 9 10
20
0.01
0.1
1
10
100
1000
10000
t
[s]
I
PD
/
I
PD
>inv
I
PD
/
I
PD
>>inv
t
PD
>
inv
= 1 s
t
PD
>>
inv
= 1 s
t
PD
>
inv
= 0.5 s
t
PD
>>
inv
= 0.5 s
t
PD
>
inv
= 0.2 s
t
PD
>>
inv
= 0.2 s
t
PD
>
inv
= 0.1 s
t
PD
>>
inv
= 0.1 s
t
PD
>
inv
= 0.02 s
t
PD
>>
inv
= 0.02 s
t
PD
>
inv
= 10 s
t
PD
>>
inv
= 10 s
t
PD
>
inv
= 5 s
t
PD
>>
inv
= 5 s
t
PD
>
inv
= 60 s
t
PD
>>
inv
= 60 s
Note: match of operating and setting time takes place when I
PD
/I
PD
>
inv
= 4 or I
PD
/I
PD
>>
inv
= 4
t
=
t
PD
>
inv
·
[(
I
PD
/
I
PD
>
inv
)
2
]
16
t
=
t
PD
>>
inv
·
[(
I
PD
/
I
PD
>>
inv
)
2
]
16