Thytronic Pro-N NVA100X-D - Phase overcurrent 50;51 side H and side L - I2 t inverse curves (I2 t=K)

360
NVA100X-D - Manual - 02 - 2016
APPENDIX
Phase overcurrent 50/51 side H and side L - I
2
t inverse curves (I2t=K)—
F_51-I2t-Char.ai
1.1
2 345678 9 10 20
I /I
(H)
>inv
I /I
(H)
>>inv
I /I
(L)
>inv
I /I
(L)
>>inv
0.01
0.1
1
10
100
1000
10000
t [s]
60 s
10 s
10 s
5 s
5 s
1 s
0.5 s
0.2 s
t>
inv
= 0.1 s
t>
inv
= 0.02 s
t =
t
(H)
>
inv
t
(H)
>
inv
t
(L)
>
inv
t
(H)
>>
inv
t
(L)
>>
inv
·
[(I/I
(H)
>
inv
)
2
]
16
t =
t
(L)
>
inv
·
[(I/I
(L)
>
inv
)
2
]
16
t =
t
(H)
>>
inv
·
[(I/I
(H)
>>
inv
)
2
]
16
t =
t
(L)
>>
inv
·
[(I/I
(L)
>>
inv
)
2
]
16
Note: match of operating and setting time takes place when I/I
(H)
>
inv
or I/I
(L)
>
inv
= 4