Siemens SIPROTEC 7SJ531 - Page 81

-ETHOD OF OPERATION3*
6

#
' #
 -ULTI SHOT DELAYED AUTO RECLOSURE
4HE INTERNAL AUTO RECLOSE FEATURE IN 3* WILL ALSO
PERMIT MULTI
SHOT RECLOSURE UP TO  CONSECUTIVE
$!2
CYCLES 4HE ACTION TIME CAN BE INDEPENDENTLY
SET FOR THESE $!2 CYCLES
$IFFERENT NUMBERS OF $!2 CYCLES CAN BE SET FOR SING
LE
PHASE FAULTS AND MULTI PHASE FAULTS 4HE SET
NUMBER OF $!2 CYCLES DOES NOT INCLUDE THE FIRST 2!2
CYCLE
4HE DEAD TIMES CAN BE INDIVIDUALLY SET FOR TRIP AFTER
SINGLE
PHASE FAULTS AND MULTI PHASE FAULTS
%ACH NEW PICK
UP RESTARTS THE ACTION TIME
$!2 4
!#4 WITHIN WHICH A TRIPPING COMMAND MUST
OCCUR !FTER FAULT CLEARANCE THE DEAD TIME BEGINS !T
THE END OF THIS THE CIRCUIT BREAKER IS GIVEN A NEW
CLOSING COMMAND 3IMULTANEOUSLY THE RECLAIM TIME
4
2%#,!)- 3ECTION  IS STARTED
!S LONG AS THE PERMITTED NUMBER OF CYCLES HAS NOT
BEEN REACHED THE RECLAIM TIME IS RESET BY EACH NEW
PICK
UP AND RECOMMENCES WITH THE NEXT CLOSING
COMMAND
)F ONE OF THE CYCLES IS SUCCESSFUL THAT IS AFTER RECLOS
URE THE FAULT IS NO LONGER PRESENT THE RECLAIM TIME
4
2%#,!)- EQUALLY RUNS OUT AND ALL FUNCTIONS RE
TURN TO THE QUIESCENT CONDITION 4HE NETWORK FAULT IS
CLEARED
)F NONE OF THE !2
CYCLES HAS BEEN SUCCESSFUL THEN
THE SHORT
CIRCUIT PROTECTION CARRIES OUT A FINAL DIS
CONNECTION AFTER THE LAST PERMISSIBLE CYCLE IN THE
STAGE THAT IS VALID FOR FINAL TRIP 4HE LOCK
OUT TIME
4
,/#+ 3ECTION  IS STARTED &OR THIS TIME
CLOSE COMMAND FROM THE !2
FUNCTION IS LOCKED
4HE SUBSEQUENT CYCLES $!2 CAN BE BLOCKED BY A
BINARY INPUT
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