Functions
6-2017SA6 Manual
C53000-G1176-C156-2
Control of the
Internal Automatic
Reclosure by an
External Protection
Device
If the 7SA6 is equipped with the internal automatic reclosure function, it may also be
controlled by an external protection device. This is of use for example on line ends with
redundant protection or additional back-up protection when the second protection is
used for the same line end and has to work with the automatic reclosure function inte-
grated in the 7SA6.
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 con-
trolled by the fault detection (pickup) or by the trip command of the external protection
(see also above under “Operating Modes of the Automatic Reclosure Function”, page
191).
If the automatic reclosure is controlled by the trip command
, the following inputs and
outputs are recommended:
The automatic reclosure function is started via the binary inputs:
2711 >AR Start general fault detection signal for automatic reclosure (on-
ly required for action time),
2712 >Trip L1 AR trip command L1 for automatic reclosure,
2713 >Trip L2 AR trip command L2 for automatic reclosure,
2714 >Trip L3 AR trip command L3 for automatic reclosure,
The general fault detection determines the starting of the action times. It is also nec-
essary if the automatic reclosure is to detect evolving faults by fault detection. In other
cases this input information is superfluous.
The trip commands decide whether the dead time for single-pole or three-pole reclose
cycles is activated or whether the reclosure is blocked in the event of a three-pole trip
(depending on the set dead times).
Figure 6-108 for example shows the interconnection between the internal automatic
reclosurefunctioninthe7SA6andanexternalprotectiondevice.
To achieve three-pole coupling of the external protection and to release, if necessary,
its accelerated stages before reclosure the following output signals 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. releases the stage of the external
protection device for reclosure, the corresponding out-
puts can be used for other cycles. This output can be
omitted if the external protection does not require an
overreaching stage (e.g. distance protection or compari-
sonmodewithdistanceprotection).
2820 AR Program1pole internal automatic reclosure function is programmed for
one pole, i.e. only recloses after single-pole tripping.
Thisoutputcanbeomittedifnooverreachingstageis
required (e.g. distance protection or comparison mode
with distance protection).
Instead of the three phase-segregated trip commands, the single-pole and three-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 7SA6:
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