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9 – 15
Short-time delayed short-circuit protection switchable to I
2
t
Trip units ETU745 - 776 make it possible to switch over from a constant delay time to an I
2
t-characteristic. In this way, the delay time
depends on the short-circuit current, but with a constant I
2
t
sd
-value, providing better coordination with downstream fuses.
In this case, the setting options for the short-time delay t
R
are as follows:
Switchover to the I
2
t
sd
characteristic can be made via:
- the t
sd
rotary coding switch (ETU745); this must be set to a value in the white area.
.
- the graphical display (ETU776)
- TD400 and the software "powerconfig"
- the COM modules with a PC with the software “powerconfig” installed
Changeable parameter sets
The trip unit ETU776 contains two complete sets of protective parameters and can be switched between them locally or remotely.
This enables lowering instantaneous and short-time settings for arc flash mitigation as well as changing parameters when the source
of supply changes between utility and generator.
Switching between parameter sets can be made manually via:
- the graphical display (ETU776)
or remotely via:
- the
Cublicle
BUS
with an input signal at the digital input module.
- the PROFIBUS DP
- the PROFINET IO, Modbus TCP and Modbus RTU.
Settings for t
sd
ETU745
t
sd
= 0.1 / 0.2 / 0.3 / 0.4 sec. (at 12 x I
n
)
ETU776
t
sd
= 0.1 - 0.4 sec. (at 12 x I
n
)
Содержание UL 489
Страница 36: ...5 21 Frame size II 3000 A Frame size III 1 Holes 14 mm 0720 1 0721_nu ...
Страница 63: ...7 2 Horizontal connectors 0733_nu top view ...
Страница 64: ...7 3 Rear vertical connectors 0734_nu top view rear view ...
Страница 65: ...7 4 Front connectors 0736_nu front view top view ...
Страница 66: ...7 5 Front connectors and pressure wire terminals 0737_nu top view front view ...
Страница 67: ...7 6 7 2 Frame size II fixed mounted version 0494 3_nu ...
Страница 68: ...7 7 Class C always 0494 5_nu top view rear view ...
Страница 69: ...7 8 2500 0738_nu LH side view front view ...
Страница 71: ...7 10 7 4 Frame size III fixed mounted version 0495 1_nu LH side view ...
Страница 72: ...7 11 0495 2_nu top view top view ...
Страница 73: ...7 12 0495 3_nu top view rear view ...
Страница 75: ...7 14 7 5 Door cut outs fixed mounted circuit breaker Frame size I 0735_nu ...
Страница 76: ...7 15 Frame size II III 0496_nu ...
Страница 77: ...7 16 7 6 Frame size I draw out version 0745_nu ...
Страница 78: ...7 17 0746_nu rear view top view ...
Страница 79: ...7 18 0747_nu bottom view ...
Страница 80: ...7 19 0748_nu ...
Страница 81: ...7 20 0749_nu ...
Страница 82: ...7 21 7 7 Frame size II draw out version 0490 1_ul ...
Страница 86: ...7 25 7 8 Frame size III draw out version ...
Страница 87: ...7 26 ...
Страница 88: ...7 27 ...
Страница 89: ...7 28 7 9 Door cut outs for draw out circuit breakers Frame size I 0750_nu ...
Страница 91: ...7 30 7 11 External sensor for neutral conductor WLNCT2 ...
Страница 92: ...7 31 WLNCT3 ...
Страница 107: ...9 5 I tripping Ground fault tripping ...
Страница 256: ...15 12 Installing FS II and FS III 1 Socket head cap screw M5 with washer and nut 1 2 3 4 6 5 7 8 Size 4 5 Nm 45 lb in ...
Страница 307: ...22 2 Installing the door sealing frame Not for use with fuse carriages Catalog No Door sealing frame WLDSF 1 2 3 ...
Страница 351: ......