Mitsubishi Electric 700 Series Programming Manual page 126

POINT
(1) Ladders differ as shown below between when MPS, MRD and MPP are used and when they
are not used.
Ladder using MPS, MRD and MPP
(2) Use the same number of MPS and MPP instructions. If they differ in the number of used
instructions, operation will be performed as described below.
1) If the MPS instructions are used more than MPP instructions, the ladder is changed and
the built-in PLC function performs operation according to the new ladder.
Before change
After change
2) If the MPP instructions are used more than MPS instructions, that ladder block results in
a ladder creation error, and the built-in PLC function cannot perform normal operation.
Ladder not using MPS, MRD and MPP
When MPP is replaced by NOP
Sequence Instructions
Coding
Coding
3
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