Siemens SIPROTEC 4 7SJ61 Manual page 151

that are only supposed to work when reclosing is enabled (see also side title "Reclosing Before Selectivity"
further above).
The automatic reclosing function is statically blocked if:
•
The signal
tion is not initiated (associated message:
•
The signal
the automatic reclosing function is not initiated (associated message:
•
The number of allowable reclosing attempts set for both reclosing programs is zero (associated message:
79 no cycle ),
•
No protection functions (parameters 7150 to 7163) or binary inputs are set to initiate the automatic
reclosing function (associated message:
•
The circuit breaker position is reported as being "open" and no trip command applies (associated
message: 79 BLK: CB open ). This presumes that 7SJ61 is informed of the circuit breaker position via
the auxiliary contacts of the circuit breaker.
Dynamic Blocking
Dynamic blocking of the automatic reclosing function occurs in those cases where the reclosing program is
active and one of the conditions for blocking is fulfilled. The dynamic blocking is signaled by the message
DynBlock . The dynamic blocking is associated with the configurable blocking time SAFETY 79 ready. This
blocking time is usually started by a blocking condition that has been fulfilled. After the blocking time has
elapsed, the device checks whether or not the blocking condition can be reset. If the blocking condition is still
present or if a new blocking condition is fulfilled, the blocking time is restarted. If, however, the blocking
condition no longer exists after the blocking time has elapsed, the dynamic blocking will be reset.
Dynamic blocking is initiated if:
•
The maximum number of reclosure attempts has been achieved. If a trip command now occurs within
the dynamic blocking time, the automatic reclosure program will be blocked dynamically (indicated by
Max. No. Cyc ).
•
The protection function has detected a three-phase fault and the device is programmed not to reclose
after three-phase faults (indicated by
•
if the maximum waiting period T DEAD DELAY for the delay of the dead time initiation by binary inputs
expires without binary input
•
The action time has elapsed without a TRIP command being issued. Each TRIP command that occurs after
the action time has expired and before the picked-up element drops out, will initiate the dynamic
blocking (indicated by
•
A protection function trips which is to block the automatic reclosure function (as configured). This applies
irrespective of the status of the automatic reclosure system (started / not started) if a TRIP command of a
blocking element occurs (indicated by
•
The circuit breaker failure function is initiated.
•
The circuit breaker does not trip within the configured time T-Start MONITOR after a trip command
was issued, thus leading to the assumption that the circuit breaker has failed. (The breaker failure moni-
toring is primarily intended for commissioning purposes. Commissioning safety checks are often
conducted with the circuit breaker disconnected. The breaker failure monitoring prevents unexpected
reclosing after the circuit breaker has been reconnected, indicated by
•
wenn der Leistungsschalter nach Ablauf der Leistungsschalterüberwachungszeit nicht schaltbereit ist,
vorausgesetzt die Leistungsschalterabfrage ist wirksam gestellt (Adresse 7113 CHECK CB? = Chk each
cycle, signalisiert durch die Meldung
SIPROTEC 4, 7SJ61, Manual
C53000-G1140-C210-6, Edition 05.2016
>BLOCK 79 FNo. 2703) is present at a binary input, as long as the automatic reclosing func-
>CB Ready (FNo. 2730) indicates that the circuit breaker disappears via the binary input, if
>79 DT St.Delay having been disabled during this time period.
79 Tact expired ).
>BLOCK 79 ),
79 no starter ),
79 BLK:3ph p.u. ).
79 BLK by trip ).
79 T-CBreadyExp ),
2.11 Automatic Reclosing System 79
>CB Ready ),
79 T-Start Exp ).
Functions
79
79
151