Mitsubishi Electric MELSEC iQ-F Series - Page 106

104
8 SFC PROGRAM
8.5 SFC Program Execution Order
■Transition operation
The transition operation with/without continuous transition in the following SFC program is shown below. (Page 107
Continuous transition ON/OFF operation)
• Without continuous transition
*1 In the case of coil HOLD step the action is not executed in the contact OFF status.
Steps (1) to (4) are activated, and the actions (A) to (D) are executed.
Although the transition (a) to (c) for Steps (1) to (3) become TRUE, the
transition (d) for Step (4) becomes FALSE.
Scan Description
Scan 1 Step (1) is activated and the action (A) is executed in the contact OFF status after the execution in the contact ON status.
*1
Scan 2 Step (2) is activated and the action (B) is executed in the contact OFF status after the execution in the contact ON status.
*1
Scan 3 Step (3) is activated and the action (C) is executed in the contact OFF status after the execution in the contact ON status.
*1
Scan 4 Step (4) is activated and the action (D) is executed in the contact ON status.
Scan 5 and after Step (4) is active until the transition (d) becomes TRUE, and the action (D) is executed in the contact ON status.
(A)(1)
(B)(2)
(C)(3)
(D)(4)
(d)
(c)
(a)
(b)
(A)(1)
(B)(2)
(C)(3)
(D)(4)
(d)
(c)
(a)
(b)
Scan 1
(1) Active
(A)
Execution in the
contact ON status
(A) Execution in the
contact OFF status
(a) TRUE
End processing
Scan 2
Scan 3
Scan 4 Scan 5
(2) Active
(B)
Execution in the
contact ON status
(B) Execution in the
contact OFF status
(b) TRUE
End processing
(3) Active
(C)
Execution in the
contact ON status
(C) Execution in the
contact OFF status
(c) TRUE
End processing
(4) Active
(D)
Execution in the
contact ON status
(d) FALSE
End processing
(4) Active
(D)
Execution in the
contact ON status
(d) FALSE
End processing