Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 112

Series sequence
When the transition becomes TRUE, the active state transitions from the preceding step to the subsequent step.
(1)
(2)
(3)
Selective sequence (divergence/convergence)
A step branches to multiple transitions, and only the step in the line where the transition becomes TRUE first is activated. The
next step is activated when the transition immediately before convergence, which is in the line where the transition becomes
TRUE first, becomes TRUE.
Item Description
Divergence
(1)
(4)
Convergence
(3)
(5)
8 SFC PROGRAM
110
8.2 Structure
When the transition (2) becomes TRUE while the step (1) is active, the step (1) is deactivated and the step (3) is
activated.
(2) (3)
(5)
(4)
(1) (2)
When the step (1) is active, the step (4) or (5) is activated depending on which of the
transition (2) and transition (3) becomes TRUE first.
The step (1) becomes inactive. However, if it is a HOLD step [SC, SE, ST], the step
holds the coil output or action according to its attribute.
• If multiple transitions become TRUE simultaneously, the condition to the left will take
precedence.
• Subsequent processing will proceed from step to step in the selected column until
another convergence occurs.
When the transition (1) or transition (2) on the activated branch becomes TRUE, the
step (5) is activated.
The activated step (3) or step (4) becomes inactive. However, if it is a HOLD step [SC,
SE, ST], the step holds the coil output or action according to its attribute.