30
Feeder terminal SPAC 531 C1 used for the
protection of an outgoing feeder in a one-breaker
system. The auto-reclose unit is started by the
tripping signals of the phase overcurrent and
neutral overcurrent modules.
In the application illustrated in Fig. 11 auto-
reclosing can be started by the tripping signal of
the high-set and low-set phase overcurrent stage
and the low-set stage of the earth-fault module.
The operate time of the stage starting the auto-
reclose unit must not be longer than the reclaim
time selected for the auto-reclose unit. Should
the operate time be longer than the reclaim
time, the auto-reclose unit resets before a new
start signal is received and the sequence will not
be completed.
In the application presented in example 2 the
starting times of the auto-reclose unit have to be
set at zero, because otherwise there will not be
enough time for the auto-reclose unit to be
started by the tripping signal. To prevent the
auto-reclose module from being started by the
starting signal of the low-set phase overcurrent
and low-set neutral overcurrent stage (I> or I
ϕ
>)
the SGB/1 switches on the PC boards of the
concerned modules have to be in position 0.
Since the start of the I>> stage is used for
blocking the auto-reclose unit, the starting sig-
nal is routed to the auto-reclose unit via the
SGB/3 switch.
The SGB switches on the PC boards of the relay
modules and the SGR switches at the front edge
of the I/O module SPTR 6B11 should be set as
follows:
Example 2.
Switch
SGB/SPCJ 3C3
SGB/SPCS 3C4
SGR
1
0 no I> start to AR2
0 no I
ϕ
> start to AR3
0 no I> start to SIGNAL 3
2
0 no I>> start to AR2
0 no I
ϕ
>> start to AR3
1 I> and I>> trip to
SIGNAL 1
3
1 I>> start to AR1
0 no I
ϕ
>> start to AR1
1 I
ϕ
> trip to TRIP output
4
0 no block. BS 1 to t>
0 no block. BS 1 to t>
0 not in use
5
0 no block. BS 1 to t>> 0 no block. BS 1 to t>>
0 not in use
6
0 no block. BS 2 to t>
0 no block. BS 2 to t>
0 not in use
7
0 no block. BS 2 to t>> 0 no block. BS 2 to t>> 0 no TRIP sign. to
SIGNAL 1
8
0 not in use
0 not in use
0 no TRIP sign. to
SIGNAL 2