Application Guide - NP900 Series
487 (504
)
A996A
3.7.5
C
IRCUIT BREAKER WEAR
-
MONITOR
(CBW)
Circuit breaker wear (CBW) function is used for monitoring the circuit breaker lifetime
before maintenance needs due to interrupting currents and mechanical wearing. CBW
function uses the circuit breaker manufacturer given data for the breaker operating cycles
in relation to the current breaker has operated. CBW function is integrated into the
controllable object function and can be enabled and set under object function. CBW
function is independent function and initializes as separate independent instance which
has own events and settings not related to the object it is linked to.
Figure 3.7.5-232 Example of the circuit breaker interrupting life operations.
Function is triggered from the circuit breaker open command output and it monitors the
three phase current values in the tripping/opening moment. The maximum interrupting life
operations value per each phase are calculated from these currents which is cumulatively
deducted from the starting value of the operations. It is possible to set up two separate
alarm levels which are activated when the interrupting life operations value is below the
setting limit.
Outputs of the function are Alarm 1 and Alarm 2 signals. Setting parameters are static
inputs for the function which are changed only by user input in the setup phase of the
function.
Inputs for the function are setting parameters and measured and pre-processed current
magnitudes and binary output signals. Function output signals can be used for direct IO
controlling and also for user logic programming. The function registers its operation into
12 last time-stamped registers and also generates general time stamped ON/OFF events
to the common event buffer from each of the two output signal. Time stamp resolution is
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...