Application Guide - NP900 Series
401 (504
)
A996A
1.
Earth fault is found in the protected line which causes directional earth fault protection
I0Dir> to start and calculate the operating time for the trip.
2.
I0Dir> trips and gives open command to the breaker open coil. Autoreclosing REQ2 is
initiated and AR running, AR2 Requested and Shot1 Running signals are activated.
3.
Circuit breaker is opened and I0Dir> Trip signal is released and simultaneously REQ2
signal for autorecloser is released. Recloser starts to calculate the Shot1 Dead Time
for closing the breaker.
4.
Dead Time for Shot1 is exceeded and autorecloser sends close request for the Object
breaker, the close conditions are met and the breaker close command is sent to
breaker close coil.
5.
Circuit Breaker is closed towards the fault which was not cleared by the Shot1 given
non-energized time and I0Dir> stage picks up and starts to calculate operating time for
trip. Close command is drop off after the breaker closed indication is received and the
autorecloser starts to calculate Reclaim time.
6.
I0Dir> trips and gives REQ2 request for autorecloser, autorecloser is calculating
Reclaim Time for Shot1 and while during this time new request is received recloser will
jump to next available Shot for this request. Shot2 is next which is allowed for REQ2
input and Shot2 Running signal is set to active and Shot1 Running is drop off.
7.
Circuit breaker is opened and I0Dir> Trip signal is released and simultaneously REQ2
signal for autorecloser is released. Recloser starts to calculate the Shot2 Dead Time
for closing the breaker.
8.
Dead Time for Shot2 is exceeded and autorecloser sends close request for the Object
breaker, the close conditions are met and the breaker close command is sent to
breaker close coil.
9.
Circuit breaker is closed towards the fault which was not cleared by the Shot2 given
non-energized time and I0Dir> stage picks up and starts to calculate operating time for
trip. Close command is drop off after the breaker closed indication is received and the
autorecloser starts to calculate Reclaim time.
10.
I0Dir> trips and gives REQ2 request for autorecloser, autorecloser is calculating
Reclaim Time for Shot2 and while during this time new request is received recloser will
jump to next available Shot for this request. For this scheme is not anymore available
shots so autorecloser initializes Final Trip state and drops AR Running, Shot2 Running
and REQ2 Running signals. Autorecloser enters to Lock-out state preventing further
requests for reclosing.
11.
Circuit breaker is opened and I0Dir> Trip signal is released. Simultaneously REQ2
signal is released and recloser is now in steady Lock-out state waiting for manual
reset from user and re-initialization by closing the breaker.
Содержание NP900 Series
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Страница 49: ...Application Guide NP900 Series 49 504 A996A Figure 3 2 1 3 25 Definite time operating characteristics...
Страница 50: ...Application Guide NP900 Series 50 504 A996A Figure 3 2 1 3 26 IEC predefined characteristics NI VI LTI and EI...
Страница 52: ...Application Guide NP900 Series 52 504 A996A Figure 3 2 1 3 28 IEEE predefined characteristics EI MI and VI...
Страница 243: ...Application Guide NP900 Series 243 504 A996A Figure 3 3 2 1 122 NPS biased thermal trip curves with kNPS values 7 and 10...
Страница 491: ...Application Guide NP900 Series 491 504 A996A 3 7 5 6 SETTING EXAMPLE...
Страница 504: ...Application Guide NP900 Series 504 504 A996A A996A...