found in menus 6230, 7080 and 8190. On the AGC Mains controller (option G5), the spring load feedback from the tie breaker
can be connected instead of the GB spring load feedback.
2. Digital input: Two configurable inputs to be used for feedbacks from the breakers: One for GB/TB spring loaded and one for MB
spring loaded. After the breaker has been opened it will not be allowed to close again before the configured inputs are active.
The inputs are configured in the utility software. When the timers are counting, the remaining time is shown in the display.
If the two solutions are used together, both requirements are to be met before closing of the breaker is allowed.
Breaker LED indication
To alert the user that the breaker close sequence has been initiated but is waiting for permission to give the close command, the
LED indication for the breaker will be flashing yellow in this case.
If the breaker needs time to reload the spring after it has opened, then the AGC can take this delay into account. This can be
controlled through timers in the AGC or through digital feedbacks from the breaker, depending on the breaker type.
6.15.4 Breaker spring load time principle
The diagram shows an example where a single AGC in island operation is controlled by the AUTO start/stop input.
This is what happens: When the AUTO start/stop input deactivates, the GB opens. The AUTO start/stop is reactivated immediately
after the GB has opened, for example by the operator through a switch in the switchboard. However, the AGC waits a while before it
issues the close signal again, because the spring load time must expire (or the digital input must be activated - not shown in this
example). Then the AGC issues the close signal.
Spring load time
GB closed
GB open
Auto Start/stop ON
Auto Start/stop OFF
t [sec]
6.15.5 Racked out breaker
Racked out breaker is a function which is used when the breaker's test mode is active or when the breaker is out for maintenance.
The feature “racked out breaker” informs the system that the physical position of the breaker is open no matter the position feedback
of the actual breaker, which makes it possible to operate the racked out breaker without interfering with the rest of the system.
INFO
When the function Racked Out Breaker is activated, the specific controller expects the breaker to physically be
disconnected from the busbar, and thereby the breaker can be opened and closed instantly without any synchronisation
check no matter the busbar state.
When the breaker is out for maintenance, the position feedback might not be present on the controller which causes a position
failure alarm, and while the breaker is in test mode, the technician might operate the breaker manually which causes a breaker Ext.
tripped alarm.
If the above mentioned alarms are triggered while the racked out breaker is active, alarms are suppressed by changing the fail class
of the specific alarms to Warning. This ensures that the alarm will not interfere with other breakers in the system.
DESIGNER'S HANDBOOK 4189341275A EN Page 132 of 196
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