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Auto-Reclose Function (79)
The auto-reclose (AR) matrix in the following Figure 6.3 describes
the start and trip signals forwarded to the auto-reclose function.
AR-matrix
Ready
(Wait for
AR-request)
Critical
Shot 1
AR1
AR2
Shot 2
Shot 3...5
Figure 6.3 – Auto-Reclose Matrix
The AR matrix above defines which signals (the start and trip
signals from protection stages or digital input) are forwarded to
the auto-reclose function. In the AR function, the AR signals can
be configured to initiate the reclose sequence. Each shot from 1
to 5 has its own enabled/disabled flag. If more than one AR
signal activates at the same time, AR1 has highest priority and
AR2 the lowest. Each AR signal has an independent start delay
for the shot 1. If a higher priority AR signal activates during the
start delay, the start delay setting will be changed to that of the
highest priority AR signal.
After the start delay the circuit-breaker (CB) will be opened if it
is closed. When the CB opens, a dead time timer is started. Each
shot from 1 to 5 has its own dead time setting.
After the dead time the CB will be closed and a discrimination
time timer is started. Each shot from 1 to 5 has its own
discrimination time setting. If a critical signal is activated during
the discrimination time, the AR function makes a final trip. The
CB will then open and the AR sequence is locked. Closing the
CB manually clears the "locked" state.
After the discrimination time has elapsed, the reclaim time timer
starts. If any AR signal is activated during the reclaim time or
the discrimination time, the AR function moves to the next shot.
The reclaim time setting is common for every shot.
If the reclaim time runs out, the auto-reclose sequence is
successfully executed and the AR function moves to ready -state
and waits for a new AR request in shot 1.
Control Functions
Start delay
Dead time
0...300 s
In use
0...300 s
0...300 s
In use
Not in use
0...300 s
In use
6-9
Discrimination
Reclaim time
time
0...300 s
0...300 s
0...300 s
0...300 s
857-UM001A-EN-P – July 2009
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