The interlocking logic for earth switch for the topology is shown in
IEC09000606-1-en.vsd
IEC09000606 V1 EN
Figure 49:
Interlocking condition for earth switch for power system topology
The output of this interlocking condition ES_EN, is connected to functional input of
SCILO at OPEN_EN and CLOSE_EN as shown in
IEC09000607-1-en.vsd
IEC09000607 V1 EN
Figure 50:
Interlocking condition connected to SCILO
A situation may occur where power apparatus have different open and closing logic,
for example, in case of circuit breaker, where any interlocking condition for opening
may not exist, but closing may require some interlocking checks (like the spring is
charged or there is a trip signal, for example). Under such circumstances, logical
TRUE may be connected to OPEN_EN and CLOSE_EN may be connected with
condition obtained from the logic prepared.
The POSOPEN and POSCLOSE inputs of SCILO require the information about the
current status of the apparatus for which the SCILO is used. For example, in the earth
switch, the binary input indicating the information about the earth switch in open
position and closed position is connected to POSOPEN and POSCLOSE inputs of the
SCILO respectively. This information can be connected directly from the binary
inputs containing earthswitch position information or may be connected as a feedback
loop obtained from DAXCBR/DAXSWI function. Both possibilities for a SCILO
handling circuit breaker are shown in
Section 5
1MRS756800 F
Protection and control engineering
72
630 series
Engineering Manual