Thytronic Pro-N NVA100X-D - Phase overcurrent 50;51 side H and side L - Long Time Inverse curve (IEC 60255-3;BS142 type B)

APPENDIX
329
NVA100X-D - Manual - 02 - 2016
Phase overcurrent 50/51 side H and side L - Long Time Inverse curve (IEC 60255-3/BS142 type B)—
F_51N-IEC-LITB-Char.ai
1.1
2 3 4 5 6 7 8 9 10 20
I /I
(H)
>inv
I /I
(L)
>inv
0.01
0.1
1
10
100
1000
10000
t [s]
10 s
60 s
5 s
1 s
0.5 s
0.2 s
0.02 s
0.1 s
t =
t
(H)
>
inv
t
(H)
>
inv
·
[(I/I
(H)
>
inv
) -1]
120
t =
t
(L)
>
inv
t
(L)
>
inv
·
[(I/I
(L)
>
inv
) -1]
120
Nota: il tempo d’intervento impostato è riferito ad un valore di corrente pari a I/I
(H)
>
inv
o I/I
(L)
>
inv
= 121