Functions
2.17 Automatic Reclosure Function (optional)
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
330
Control of the internal automatic reclosure by an external protection device
If the 7SD5 is equipped with the internal automatic reclosure function, this can also be controlled by an external
protection device. This is of use, for example, on line ends with redundant protection or additional back-up pro-
tection when the second protection is used for the same line end and has to work with the automatic reclosure
function integrated in the 7SD5.
The binary inputs and outputs provided for this functionality must be considered in this case. It must be decided
whether the internal automatic reclosure function is to be controlled by the starting (pickup) or by the trip
command of the external protection (see also above under „Control Mode of the Automatic Reclosure“).
If the automatic reclosure function is controlled by the
trip command
, the following inputs and outputs are rec-
ommended:
The automatic reclosure function is started via the Binary inputs:
2711
„>AR Start“
General fault detection for the automatic reclosure circuit (only required for
action time),
2712
„>Trip L1 AR“
Trip command L1 for the automatic reclosure circuit,
2713
„>Trip L2 AR“
Trip command L2 for the automatic reclosure circuit,
2714
„>Trip L3 AR“
Trip command L3 for the automatic reclosure circuit.
The general pickup is decisive for starting the action times. It is also required if the automatic reclosing function
has to detect sequential faults via pickup. In other cases, this input information is irrelevant.
The trip commands decide whether the dead time is activated for 1-pole or 3-pole reclose cycles or whether
the reclosure is blocked in the event of a 3-pole trip (depending on the configured dead times).
Figure 2-163 shows the interconnection between the internal automatic reclosure function of the 7SD5 and an
external protection device, as a connection example for 1-pole cylces.
To achieve 3-pole coupling of the external protection and to release, if necessary, its accelerated stages before
reclosure, the following output functions are suitable:
2864
„AR 1p Trip Perm“
Internal automatic reclosure function ready for 1-pole reclose cycle, i.e.
allows 1-pole tripping (logic inversion of the 3-pole coupling).
2889
„AR 1.CycZoneRel“
Internal automatic reclosure function ready for the first reclose cycle, i.e. re-
leases the stage of the external protection device for reclosure, the corre-
sponding outputs can be used for other cycles. This output can be omitted if
the external protection does not require an overreaching stage (e.g. differ-
ential protection or comparison mode with distance protection).
2820
„AR Program1pole“
Internal automatic reclosure function is programmed for one pole, i.e. only
recloses after 1-pole tripping. This output can be omitted if no overreaching
stage is required (e.g. differential protection or comparison mode with dis-
tance protection).
Instead of the 3-phase-segregated trip commands, the 1-pole and 3-pole tripping may also be signalled to the
internal automatic reclosure function - provided that the external protection device is capable of this -, i.e.
assign the following binary inputs of the 7SD5:
2711
„>AR Start“
General fault detection for the internal automatic reclosure function (only re-
quired for action time),
2715
„>Trip 1pole AR“
Trip command 1-pole for the internal automatic reclosure function,
2716
„>Trip 3pole AR“
Trip command 3-pole for the internal automatic reclosure function.
If only 3-pole reclosure cycles are to be executed, it is sufficient to assign the binary input
„>Trip 3pole AR“
(No. 2716) for the trip signal. Figure 2-164 shows an example. Any overreaching stages of the external protec-
tion are enabled again by
„AR 1.CycZoneRel“
(No. 2889) and of further cycles, if applicable.
