Functions
2.11 Automatic Reclosure Function 79 (Optional)
SIPROTEC, 7SD80, Manual
E50417-G1140-C474-A1, Release date 09.2011
149
The options for handling evolving faults are described in Section 2.11 under margin heading „Handling Evolving
Faults“. You can define recognition of an evolving fault at address
3406
EV. FLT. RECOG.
.
EV. FLT.
RECOG.
with PICKUP
means that during a dead time each
pickup
of a protection function will be interpreted
as an evolving fault. With
EV. FLT. RECOG.
with TRIP
a fault during a dead time is only interpreted as an
evolving fault if it has led to a
trip command
by a protection function. This may also include trip commands
which are received from an external device via a binary input or which have been transmitted from another end
of the protected object. If an external protection device operates together with the internal auto-reclosure,
evolving fault detection with pickup presupposes that a pickup signal from the external device is also connected
to the 7SD80; otherwise an evolving fault can only be detected with the external trip command even if
with
PICKUP
was set here.
The reaction to evolving faults can be selected under address
3407
.
EV. FLT. MODE
Stops 79
means that
no reclosing takes place after detection of an evolving fault. This is recommended if stability problems are an-
ticipated when reclosing after the 3-pole dead time. If a 3-pole reclose cycle is to be initiated by tripping of the
evolving fault, set
EV. FLT. MODE
=
starts 3p AR
. In this case, a separately adjustable 3-pole dead time
is started with the trip command due to the evolving fault.
Address
3408
T-Start MONITOR
monitors the reaction of the circuit breaker after a trip command. If the CB
has not opened during this time (from the beginning of the trip command), the automatic reclosure is blocked
dynamically. The criterion for circuit breaker opening is the position of the circuit-breaker auxiliary contact or
the disappearance of the trip command. If a circuit-breaker failure protection (internal or external) is used on
the feeder, this time should be shorter than the time delay of the circuit-breaker failure protection so that no
reclosure takes place if the circuit breaker fails.
Note
To enable that the busbar is tripped by the breaker failure protection without preceding injection of the trip
command (by AR or BF), the time set for
3408
T-Start MONITOR
also has to be longer than the time set for
3906
50BF-2 Delay
. In this case, the AR must be blocked by a signal from the BF to prevent the AR from
reclosing after a busbar TRIP. It is recommended to connect the signal 1494
„50BF BusTrip“
to the AR input
2703
„>BLOCK 79“
via CFC.
Configuring the Automatic Reclose Function
This configuration concerns the interaction between the protection and supplementary functions of the device
and the automatic reclosure function. The selection of functions of the device which are to start the automatic
reclosure circuit and which are not to, is made here.
For the functions which are to start the auto-reclosure function, the corresponding address is set to
YES
, for the
others to
NO
. The other functions cannot start the automatic reclosure because reclosure is of little use here.
First Reclosing Cycle
Address
3450
1.AR:START
is only available if the automatic reclosing function works in the operating mode
with action time, i.e. address
134
AR control mode
=
PU w/ActionTime
or
Trip w/ActionT.
was set
during configuration of the protection functions (see Section 2.1.1.2). It determines whether the automatic re-
closing function is started with the first cycle. This parameter and different action times allow you to control the
effectiveness of the cycles (
AR control mode
=
Trip ...
.).
Address 3420
AR WITH DIFF, i.e. with differential protection
Address 3423
AR w/ INT.TRIP, i.e. with permissive underreach transfer trip (PUTT)
Address 3424
AR w/ DTT, i.e. with direct transfer trip
Address 3425
AR w/ 50(N)-B, i.e. with time overcurrent protection