Mitsubishi Electric M800VW Series Programming Manual page 175

M800V/M80V Series PLC Programming Manual (1/2)
7 Basic Instructions
7.5 Master Control Instructions
 Program example
 The master control instruction can be used in nesting.
The different master control regions are distinguished by nesting (N).
Nesting can be used from N0 through N7.
The use of nesting enables the creation of ladders which successively limit the execution condition of the program.
A ladder using nesting would appear as shown below:
Ladder as displayed in ladder mode
A
MC N0 M15
N0 M15
B
MC N1 M16
N1 M16
C
MC N2 M17
N2 M17
IB-1501667-B
N0 M15
N1 M16
N2 M17
MCR N2
MCR N1
MCR N0
Ladder as it actually operates
A
MC N0 M15
B
MC N1 M16
C
MC N2 M17
MCR N2
MCR N1
MCR N0
154
Executed when A
is ON
Executed when A
and B are ON
Executed when A,
B, and C are ON
Executed when A
and B are ON
Executed when
A is ON
No relation to
status of A, B, or C