38
Feeder terminal SPAC 531 C1 used for the
protection of an outgoing feeder in a two-
breaker system.
Fig. 17 illustrates a situation in which the feeder
terminal SPAC 531 C1 protects the outgoing
feeder in a two-breaker system. When SPAC
531 C1 is used in a two-breaker system the
function of certain output contacts have to be
changed, compare one-breaker system shown in
example1.
The SG1 switchgroups on the front panels of
the relay modules and the SGB switchgroups on
the PC boards are set in the same way as in a one-
breaker system. The SGR switchgroup at the
front edge of the I/O module SPTR 6B11 is set
as follows.
In the two-breaker systems presented in this
example the output SIGNAL 1 is used as a
second trip output. Then SGR/7 has to be in
position 1 and SGR/2 in position 0. In two-
breaker systems the I> and I>> alarm signals, as
the alarm signals I
ϕ
> and I
ϕ
>>, are routed to the
output SIGNAL 2. The SGR/8 switch has to be
in position 1. The neutral overcurrent protec-
tion has a tripping function, since the SGR/3
switch is closed. The switches SGR/4, SGR/5
and SGR/6 have no function in SPAC 531 C
and should be in position 0.
With above switch settings the output contacts
of feeder terminal SPAC 531 C1 have the fol-
lowing functions:
Example 6
Switch
SGR
1
0 no I> start to SIGNAL 3
2
0 no I> and I>> trip to SIGNAL 1
3
1 I
ϕ
> trip to TRIP output
4
0 not in use
5
0 not in use
6
0 not in use
7
1 TRIP signals to SIGNAL 1
8
1 TRIP signals to SIGNAL 2
Contact
Function
X1/3-4
Opening 1 of CB 1(I>, I>>, I
ϕ
>, I
ϕ
>>)
X1/6-7
Opening 1 of CB 2(I>, I>>, I
ϕ
>, I
ϕ
>>)
X2/1-2-3
Signal for final tripping (I>, I>>, I
ϕ
>, I
ϕ
>>)
N.B. All trip signals are routed to the same contact.
X2/4-5-6
I>> start
X2/7-8-9
I
ϕ
> start
X1/8-9-10
Self-supervision alarm (IRF)
X3/11-12
Opening 2 of CB 1 (local control, remote control, AR)
X3/13-14
Closing of CB 1
X3/15-16
Opening 2 of CB 2 (local control, remote control, AR)
X3/17-18
Closing of CB 2
The contacts for CB closing and opening 2
depend on the configuration of the control
module.
The AR parameters can be set as shown in
example 1. Then the overcurrent module will
cause only high-speed auto-reclosing and the
directional earth fault module both high-speed
and low-speed auto-reclosing.
If two separate feeder terminals are used for the
protection of the busbar, the blocking signal is
routed in parallel to the terminals.