Mitsubishi Electric MELSEC iQ-F FX5 Programming Manual page 161

Master control instructions can be used in a nested fashion. Each master control section is distinguished by
nesting (N). Nesting is available within the range N0 to N14.
A nested structure allows you to create a ladder for successively restricting program execution conditions.
A nested structure ladder is illustrated as follows:
(Left: Display on the engineering tool, Right: Actual operation)
A
N0 M15
B
N1 M16
C
N2 M17
(1) Executed when A is ON
(2) Executed when A and B are ON
(3) Executed when A, B, and C are ON
(4) Regardless of A, B, and C
MC N0 M15
N0
MC N1 M16
N1
MC N2 M17
N2
N2
MCR
N1
MCR
N0
MCR
A
M15
B
M16
C
M17
6 SEQUENCE INSTRUCTIONS
6.5 Master Control Instruction
MC N0 M15
(1)
MC N1 M16
(2)
MC N2 M17
(3)
N2
MCR
(2)
N1
MCR
(1)
N0
MCR
(4)
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