ABB RER620, Техническое руководство

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Section 5
1MAC309294-MB F
Control functions
298 RER620
Technical Manual
In case there are multiple CBBs allowed for execution, the CBB with the smallest number
is chosen. For example, if CBB2 and CBB4 request an execution, CBB2 is allowed to
execute the shot.
The autoreclose function can perform up to five autoreclose shots or cycles.
Shot pointer controller
The execution of a reclose sequence is controlled by a shot pointer. It can be adjusted with
the
SHOT_PTR
monitored data.
The shot pointer starts from an initial value “1” and determines according to the settings
whether or not a certain shot is allowed to be initiated. After every shot, the shot pointer
value increases. This is carried out until a successful reclosing or lockout takes place after
a complete shot sequence containing a total of five shots.
Figure 154: Shot pointer function
Every time the shot pointer increases, the reclaim time starts. When the reclaim time ends,
the shot pointer sets to its initial value, unless no new shot is initiated. The shot pointer
increases when the reclose time elapses or at the falling edge of the
INC_SHOTP
signal.
When
SHOT_PTR
has the value six, the AR function is in a so called pre-lockout state. If
a new initiation occurs during the pre-lockout state, the AR function goes to lockout.
Therefore, a new sequence initiation during the pre-lockout state is not possible.
The AR function goes to the pre-lockout state in the following cases:
• When the AR function is active, it stays in a pre-lockout state for the time defined by
the reclaim time
• When all five shots have been executed
• When the frequent operation counter limit is reached. A new sequence initiation
forces the AR function to lockout.
Shot
pointer
1st reclosing attempt
2nd reclosing attempt
PRE-LOCKOUT
LOCKOUT