Siemens 7SC80 Manual page 281

Automatic Reclosure with External Synchronism Check
Parameter 7139 External SYNC can be set to determine that the automatic reclosure function operates
with external synchrocheck. An external synchronization is possible if the parameter is set to YES and the
device is connected to the external synchronization check via indication 2865
binary input >Sync.release .
Note: The automatic reclosure function cannot be connected to the internal and external synchrocheck at the
same time !
Initiation and Blocking of Automatic Reclosure by Protective Elements (configuration)
At addresses 7150 to 7164 you can specify which protection functions work together with the automatic
reclosing function. They form the link between protection device and automatic reclosing function. Each
address designates a protection function together with its ANSI synonym, for example 50-2 for the 50-2
element of the non-directional overcurrent protection (address 7152).
The setting options have the following meaning:
•
Starts 79, the protective element initiates the automatic reclosure via its trip command;
No influence, the protective element does not start the automatic reclosure, it may however be initi-
ated by other functions;
Stops 79, the protective element blocks the automatic reclosure, it cannot be started by other func-
tions; a dynamic blocking is initiated.
Dead Times (1st AR)
Addresses 7127 and 7128 are used to determine the duration of the dead times of the 1st cycle. The time
defined by this parameter is started when the circuit breaker opens (if auxiliary contacts are allocated) or
when the pickup drops out following the trip command of a starter. Dead time before first automatic reclosure
for reclosing program "Phase" is set in address 7127 DEADTIME 1: PH, for reclosing program "ground" in
address 7128 DEADTIME 1: G. The exact definition of the programs is described in the functional description
at margin heading "Reclosing Programs". The length of the dead time should relate to the type of application.
With longer lines, they should be long enough to make sure that the fault arc disappears and that the air
surrounding it is de-ionized and auto-reclosure can successfully take place (usually 0.9 s to 1.5 s). For lines
supplied by more than one side, mostly system stability has priority. Since the de-energized line cannot
transfer synchronizing energy, only short dead times are allowed. Standard values are 0.3 s to 0.6 s. In radial
systems, longer dead times are allowed.
Cyclic Control of the Protection Functions by the Automatic Reclosing Function
Addresses 7200 to 7211, 7248 and 7249 allow cyclic control of the various protection functions by the auto-
matic reclosing function. This enables any protection element to be blocked selectively, set to operate instan-
taneously or according to the set delay times.
The following options are available:
•
Set value T=T, the protection element is delayed as configured, that is the automatic reclosing func-
tion does not affect the element;
instant. T=0, the protection element becomes instantaneous if the automatic reclosing function is
ready to perform the mentioned cycle
blocked T=∞, the protection element is blocked when the automatic reclosing function reaches the
cycle defined in the parameter. The element picks up, however, the expiry of the element is blocked by
this setting.
Dead Times (2nd to 4th reclosing attempt)
If more than one reclosing cycle was set, you can now configure the individual reclosing settings for the 2nd
to 4th cycle. The same options are available as for the first cycle.
For the 2nd cycle:
Address 7129
Address 7130
SIPROTEC Compact, 7SC80, Manual
E50417-G1140-C486-A8, Edition 07.2017
DEADTIME 2: PH Dead time for the 2nd reclosing attempt, phase
Dead time for the 2nd reclosing attempt ground
DEADTIME 2: G
Functions
2.14 Automatic Reclosing System 79
79 Sync.Request and the
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