ABB SPAJ 131 C User Manual And Technical Description page 16

16
Busbar system protection based on blockings
can also be used in the case of reverse supply on
the feeder, provided the reverse current does not
exceed the setting value of the high-set stage on
the feeder. In such a case the blocking signal is
generated by the high-set stage of the overcur-
rent relay of the feeder.
The blocking signals to terminals 10-11 are
linked to the high-set stage of the overcurrent
relay by means of the SGR/1 switch on the front
panel and the SGB/5 switch on the PC board of
the overcurrent module. These switches have to
be in position 1.
The blocking circuit is easily tested through the
Trip test function of the relay modules and the
display. The blocking stage of the module to
generate the blocking signal is started via the
Switch SG1/SPCJ 3C3
1 0
}
t> = 0.05...1.00 s
2 0
3 0 def. time charact.
4 1 self-holding
5 0 no I>> doubling
6 0 I>> = 2.5...20 x I
7 0
}
t>> = 0.04...1 s
8 0
∑
8
With above switch settings the output relays of
SPAJ 131 C have the following functions:
Output relay (contact)
A (65-66)
B (68-69)
C (80-81)
D (77-78)
E (70-71-72)
Trip test function (see manual "General charac-
teristics of C-type SPC relay modules"). Via
register 0 of the module to receive the blocking
signal it is checked that the blocking signal
arrives. For example in this application the high-
set stage of the overcurrent module on the
outgoing feeder is started, signal SS2. Then the
left-most digit of register 0 of the overcurrent
module is 2, which means that the tripping of
the high-set stage is blocked.
In this example the operation of the low-set
stage of the overcurrent relay is based on definite
time characteristic, but inverse time characteris-
tic is possible as well.
The selector switches of the phase overcurrent
relay SPAJ 131 C can be set as follows:
SGB/SPCJ 3C3
0 not in use
0 not in use
0 not in use
0 no blocking to t>
1 blocking to t>>
0 not in use
n
0 not in use
0 not in use
Function
CB open (I>, I>>)
Signal for final trip (I>>)
Signal for final trip (I>)
Start of I>> stage, blocking signal to the HV side
overcurrent module of the power transformer
Self-supervision alarm
SGR
1 blocking from outgoing feeders
1 I>> start to output relay D
0 no I> start to output relay D
0 no I>> trip to output relay D
0 no I>> trip to output relay C
1 I>> trip to output relay A
1 I> trip to output relay C
0 no I> trip to output relay B