752
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
34 SFC Program and Step Ladder
34.1 SFC Program
Composition of branches/recombination and dummy state
1. When a recombination line is directly connected to a branch line without a state relay
When a recombination line is directly connected to a branch line without a state relay as shown below, it is
recommended to provide a dummy state relay between the lines.
There are no dedicated numbers for dummy state relays.
Use a state relay number not used in a program as a dummy state relay.
Dummy state
relay
20
30
40
50
60
20
30
40
50
60
20
30
40
50
20
30
40
50
20
30
40
50
60
20
30
40
50
60
20
30
40
50
20
30
40
50
Deform it
as follows.
100
Dummy state
relay
101
102
103
Dummy state
relay
Dummy
state
relay