Thytronic NA30 - Phase Overcurrent 50;51 - I T Inverse Curves (I2 T=K)

APPENDIX
183
NA30 - Manual - 04 - 2022
 Phase overcurrent 50/51 - I
2
t inverse curves (I2t=K)
F_51-I2t-Char.ai
1.1
2 3 4 5 6 7 8 9 10 20
I
/I >inv
I
/I >>inv
0.01
0.1
1
10
100
1000
10000
t [s]
t>
inv
=
60 s
t>>
inv
=
60 s
t>
inv
=
10 s
t>>
inv
=
10 s
t>
inv
=
5 s
t>>
inv
=
5 s
t>
inv
= 1 s
t>>
inv
= 1 s
t>
inv
= 0.5 s
t>>
inv
= 0.5 s
t>
inv
= 0.2 s
t>>
inv
= 0.2 s
t>
inv
= 0.1 s
t>>
inv
= 0.1 s
t>
inv
= 0.02 s
t>>
inv
= 0.02 s
t =
t>
inv
·
[(I/I>
inv
)
2
]
16
Note: match of operating and setting time takes place when I/I>
inv
= 4