Mitsubishi Q Series Programming Guide

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3 SPECIFICATIONS
MELSEC-Q
3.4 Calculating the SFC Program Capacity
In order to express the SFC diagram using instructions, the memory capacity shown below is
required. The method for calculating the SFC program capacity and the number of steps when the
SFC diagram is expressed by SFC dedicated instructions is described in this section.
(1) Method for calculating the SFC program capacity
max. created
block No.+1
SFC program capacity (block 0 capacity)+(block 1 capacity)+
…
+(block n capacity)
Number of blocks being used
SFC file header capacity
SFC program START (SFCP) and END (SFCPEND) instructions
number of steps where SFC diagram is
exparessed by SFC dedicated instructions
+ (operation output total for all steps)
As shown below
Block START (BLOCK BLm) and END (BEND) instructions
Capacity of blocks
28
2 +
+
=
=
+
+ (total number of transition conditions
Number of steps where SFC diagram is expressed by SFC dedicated instructions
• Step (
, )
3 sequence steps (+) for step START (STEP
Sn) and END (SEND) instructions.
• Transition conditions (+)
1) For serial transition or selective branching coupling
4 sequence steps for transition START instruction (TRAN
TRn) and transition
destination instruction (TSET Sn).
2) For parallel branching
Total number of steps for the transition START instruction (TRAN
TRn), and
transition destination instructions (TSET Sn) for the number of parallel branches
in question.
3) For parallel coupling
Total number of steps for the transition START instruction (TRAN
TRn), and
the transition destination instructions (TSETSn) and coupling check instructions
(TAND Sn) for the (number of parallel branchings in question
1.
• Jump (
) , end step ( )
Calculated as step 0 because it is included in the previous transition condition.
• Operation outputs for each step: The capacity per step is as follows
• Total number of sequence steps for all instructions.
(For details regarding the number of sequence steps for each instruction, refer to
the QCPU (Q mode) / QnACPU Programming Manual (Common Instructions))
• Transition conditions: The capacity per transition condition is as follows
• Total number of sequence steps for all instructions.
(For details regarding the number of sequence steps for each instruction, refer to
the QCPU (Q mode) / QnACPU Programming Manual (Common Instructions))

Mitsubishi Q Series Specifications

General

Brand	Mitsubishi
Model	Q Series
Category	Control Unit
Language	English