2.10 Automatic Reclosure Function (optional)
143
7SD610 Manual
C53000-G1176-C145-4
considered to be fault-free. The setting must be smaller than the lowest expected op-
erating voltage. The setting is applied in Volts secondary. This value can be entered
as a primary value when parameterising with a PC and DIGSI. Address 3438 T U-
stable establishes the measuring time used to determine that the line is fault-free
with this returning voltage. It should be longer than any transient oscillations resulting
from line energization.
1st reclosure cycle If working on a line with adaptive dead time, no further parameters are needed for the
individual reclose cycles in this case. All the following parameters assigned to the in-
dividual cycles are then superfluous and inaccessible.
Address 3450 1.AR: START is only available if the automatic reclosure is config-
ured with action time in the operating mode, i. e. if during configuration of the protec-
tive functions (see Section 2.1.1.2) address 134 AR control mode = Pickup w/
Tact or Trip w/ Tact was set (the first setting only applies to three-pole tripping).
It determines whether automatic reclosure should be started at all with the first cycle.
This address is included mainly due to the uniformity of the parameters for every re-
closure attempt and is set to YES for the first cycle. If several cycles are performed,
you can (at AR control mode = Pickup ...) set this parameter and different
action times to control the effectiveness of the individual cycles. Notes and examples
are listed in Section 2.10 at margin heading „Action times“.
The action time 1.AR: T-ACTION (address 3451) is the timeframe after initiation
(fault detection) by any protective function which can start the automatic reclosure
function within which the trip command must appear. If no trip command is issued until
the action time has expired, there is no reclosure. Depending on the configuration of
the protective functions, 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 (address 134
AR control mode) only address 3456 and 3457 (if AR control mode = with
TRIP...) are available or address 3453 to 3455 (if AR control mode = with
PICKUP ...).
In AR control mode = with TRIP ... you can set different dead times for single-
pole and three-pole reclose cycles. Whether single-pole or three-pole tripping is trig-
gered depends solely on the initiating protective functions. Single-pole tripping is of
course only possible if the device and the corresponding protective function are also
capable of single-pole tripping:
Table 2-5 AR control mode = with TRIP...
If you only want to allow a single-pole reclose cycle, set the dead time for three-pole
tripping to ∞. If you only want to allow a three-pole reclose cycle, set the dead time for
single-pole tripping to ∞, the protection then trips three-pole for each fault type.
The dead time after single-pole tripping (if set) 1.AR Tdead1Trip (address 3456)
should be long enough for the short-circuit arc to be extinguished and the surrounding
air to be de-ionized so that the reclosure promises to be successful. The longer the
line, the longer is this time due to the charging of the conductor capacitances. Con-
ventional values are 0.9 s to 1.5 s.
For three-pole tripping (address 3457 1.AR Tdead3Trip) the network stability is the
main concern. Since the de-energized line cannot transfer synchronizing energy, only
short dead times are allowed. The usual values are 0.3 s to 0.6 s. If the device is op-
3456 1.AR Tdead1Trip is the dead time after single-pole tripping,
3457 1.AR Tdead3Trip is the dead time after three-pole tripping.
www . ElectricalPartManuals . com
To Next Page
Loading...
