Siemens siprotec 7SA522 User Manual page 320

Functions
1st reclosure cycle
6-172
scription, section 6.11.1, under subtitle "Interrogation of circuit-breaker ready state",
page 155.
If there is a risk of stability problems in the network during a three-pole interruption,
the setting in address  $'7 6\Q5HTXHVW should be <HV. In this case the voltage
of the line and busbar are checked after a three pole trip and before reclosure to de-
termine if sufficient synchronism exists. This assumes that the device has a voltage
and sync. check capability or that an external device is available for this purpose.
If only single-pole reclosure cycles are executed or no stability problems are expected
during three-pole dead times (e.g. due to close meshing of the network or in radial net-
works), set address  to 1R.
Addresses  and  are only significant if the voltage-controlled adaptive dead
time is used. Set under address  8OLYH! the limit voltage Phase–Earth above
which the line is considered to be fault-free. The setting must be smalIer than the low-
est expected operating voltage. The setting is applied in Volts secondary. This value
can be entered as a primary value when parametrizing with a PC and DIGSI
dress  7 8VWDEOH determines the measuring time used to determine that the
line is fault free with this return voltage. It should be longer than any transient oscilla-
tions resulting from line energization.
If working on a line with adaptive dead time, no further parameters are needed for the
individual reclose cycles here. All the following parameters assigned to the individual
cycles are then superfluous and inaccessible.
Address  $5 67$57 is only available if the automatic reclosure is configured
with action time in the operating mode, i. e. if address  $5 FRQWURO PRGH =
3LFNXS Z 7DFW or 7ULS Z 7DFW was set when configuring the protection func-
tions (the first setting only applies to three-pole tripping). It determines whether auto-
matic reclosure should be started at all with the first cycle. This address is included
mainly for the sake of uniformity of the parameters for all the reclosure cycles and must
be set to <HV for the first cycle. If several cycles are used it is possible to control (in
control mode with PICKUP ) the effect of the individual cycles with this parameter and
various action times. Notes and examples can be found in section 6.11.1 under subti-
tle "Action times" (page 153).
The action time $5 7$&7,21 (address ) is the time after initiation (fault de-
tection) by any protective function which can start the automatic reclosure function
within which the trip command must appear. If the command does not appear until af-
ter the action time has expired, there is no reclosure. Depending on the configuration
of the protective functions (see section 5.1) the action time may also be omitted; this
applies especially when an initiating protective function has no fault detection signal.
Depending on the configured operating mode of the automatic reclosure (see section
5.1 under address  $5 FRQWURO PRGH) only addresses  and  (if con-
trol mode ZLWK 75,3) or the addresses  to  (if operating mode
with PICKUP ) are available.
In the control mode ZLWK 75,3 it is possible to set different dead times for single-
pole and three-pole reclose cycles. Whether single-pole or three-pole tripping takes
place depends solely on the initiating protection functions. Single-pole tripping is only
possible of course if the device and the corresponding protection function are also ca-
pable of single-pole tripping.
Address  $5 7GHDG7ULS is the dead time after 1-pole tripping,
Address  $5 7GHDG7ULS is the dead time after 3-pole tripping.
If only single-pole reclose cycle are to be allowed, the dead time for three-pole tripping
must be set to ∞. If only three-pole reclose cycle are to be allowed, the dead time for
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7SA522 Manual
C53000-G1176-C119-2