Application Guide - NP900 Series
109 (504
)
A996A
3.2.9.3
F
UNCTION BLOCKING
In the blocking element the block signal is checked in the beginning of each program
cycle. Blocking signal is received from the blocking matrix for the function dedicated input.
If the blocking signal is not activated when the pick-up element activates, a START signal
is generated and the function proceeds to the time characteristics calculation.
If blocking signal is active when pick-up element activates a BLOCKED signal will be
generated and the function shall not process the situation further. If START function has
been activated before blocking signal it will reset and the release time characteristics are
processed as in case of when pick-up signal is reset.
From blocking of the function a HMI display event as well as time stamped blocking event
with information of the startup current values and fault type is issued.
Blocking signal can be tested also in the commissioning phase of the stage by software
switch signal when relay common and global testing mode is activated.
User settable variables are binary signals from the system. Blocking signal needs to reach
the IED minimum of 5 ms before the set operating delay has passed for blocking to be
active in time.
3.2.9.4
O
PERATING TIME CHARACTERISTICS FOR ACTIVATION AND RESET
The operating timers’ behavior of the function is set depending of the application. Both
timers are started from the same pick-up signal, which means that in case Retrip is used
the time grading should be set so that the Retrip time added with expected operating time
and releasing time of the CBFP pick up conditions is shorter than the set CBFP time in
order to avoid unnecessary CBFP in cases when re tripping to another breaker coil clears
the fault. In the following table are presented the setting parameters for the function time
characteristics.
Table 3.2.9.4-82 Operating time characteristics setting parameters.
Name
Range
Step
Default Description
Retrip
No
Yes
-
Yes
Retrip enabled or disabled. If Retrip is disabled the
output will not be visible and also the TRetr setting
parameter will not be available.
Retrip
time
delay
0.000…1800.000s 0.005s 0.100s
Retrip start timer, this setting defines how long the
starting condition has to last before RETRIP signal is
activated.
CBFP
0.000…1800.000s 0.005s 0.200s
CBFP start timer, this setting defines how long the
starting condition has to last before CBFP signal is
activated.
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...