Mitsubishi Electric MELSEC FX3U Programming Manual page 844

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
3. Example of parallel branch
Do not use MPS, MRD, MPP, ANB and ORB instructions in a program with branches and recombination.
Even in a load driving circuit, MPS instructions cannot be used immediately after STL instructions.
In the same way as programs for general state relays, program the drive processing first, and then program
the transfer processing.
Continuously program all transfer processing.
<SFC program>
20
X000
1
21
4. Example of parallel recombination
Do not use MPS, MRD, MPP, ANB and ORB instructions in a program with branches and recombination.
Even in a load driving circuit, MPS instructions cannot be used immediately after STL instructions.
Pay attention to the programming order so that a branch line does not cross a recombination line.
<SFC program>
29
X010
9
50
<Step ladder>
X010 X011 X012
Before recombination, first program the drive processing of state relays.
After that, program only the transfer processing to recombination state relays.
842
<Step ladder>
Y000
TRAN
31 41
39
Y010
X011 X012
TRAN
STL S29
Y010
STL S39
Drive
Y011 processing
STL S49
Y012
STL S29
STL S39
Transfer
processing
STL S49
SET S50
STL S20
Y001
X000
SET S21
SET S31
SET S41
49
Y011
<List program>
STL S29
OUT Y010
STL S39
OUT Y011
STL S49
OUT Y012
STL S29
STL S39
STL S49
LD X010
AND X011
AND X012
SET S50
35 SFC Program and Step Ladder
35.2 Step Ladder
<List program>
STL
OUT
Drive
LD
processing
SET
SET
SET
Transfer
processing
Y012
S20
Y000
X000
S21
S31
S41