Siemens 7VK512

-ETHOD OF OPERATION6+
6
#
' #

 $EAD LINE SWITCHING
&OR RELEASE OF THE CLOSING COMMAND TO ENERGIZE A
VOLT
FREE LINE FROM THE BUS BAR THE FOLLOWING CONDI
TIONS ARE CHECKED
$OES THE VOLTAGE 5 LIE BELOW THE SET VALUE 5
$OES THE VOLTAGE 5 LIE ABOVE THE SET VALUE 5
7HEN THE CONDITIONS ARE SATISFIED THE CLOSING COM
MAND IS RELEASED 4HE DURATION OF THE COMMAND CAN
BE ADJUSTED
#ORRESPONDING CONDITIONS APPLY WHEN SWITCHING A
LIVE LINE ONTO A DEAD BUS
BAR OR A DEAD LINE ONTO A
DEAD BUS
BAR
 3WITCHING AT SYNCHRONISM
4O RELEASE A CLOSING COMMAND THE FOLLOWING CONDI
TIONS ARE CHECKED
$OES THE VOLTAGE 5 LIE ABOVE THE SET VALUE 5
$OES THE VOLTAGE 5 LIE ABOVE THE SET VALUE 5
)S THE VOLTAGE MAGNITUDE DIFFERENCE \i5i i5i\
WITHIN THE PERMISSIBLE TOLERANCE 5
)S THE ANGLE DIFFERENCE \ \ WITHIN THE PER
MISSIBLE TOLERANCE 
)S THE FREQUENCY DIFFERENCE \F F\ WITHIN THE
PERMISSIBLE TOLERANCE F
7HEN THE CONDITIONS ARE SATISFIED THE CLOSING COM
MAND IS RELEASED 4HE DURATION OF THE COMMAND CAN
BE ADJUSTED
 !SYNCHRONOUS SWITCHING
&OR RELEASE OF A CLOSING COMMAND THE FOLLOWING
CONDITIONS ARE CHECKED
$OES THE VOLTAGE 5 LIE ABOVE THE SET VALUE 5
$OES THE VOLTAGE 5 LIE ABOVE THE SET VALUE 5
)S THE VOLTAGE MAGNITUDE DIFFERENCE \i5i i5i\
WITHIN THE PERMISSIBLE LIMIT 5
)S THE FREQUENCY DIFFERENCE \F F\ WITHIN THE
PERMISSIBLE DIFFERENCE F BUT LARGER THAN F
SYNC

7HEN THE CONDITIONS ARE SATISFIED THE DEVICE CALCU
LATES THE TIME TO THE NEXT INSTANT OF SYNCHRONISM
FROM THE RATE OF CHANGE OF ANGLE AND FREQUENCY DIF
FERENCE 4HE CLOSING COMMAND IS THEN RELEASED AT
THE INSTANT THAT THE CLOSING TIME OF THE BREAKER
EQUALS THE DIFFERENCE BETWEEN INSTANT OF COMMAND
AND THE NEXT INSTANT OF SYNCHRONISM 4HE DURATION OF
THE COMMAND IS ADJUSTABLE