Mitsubishi MELSEC-A series Programming Manual

6. BASIC INSTRUCTIONS
6 − 82
MELSEC-A
(3) For A3H, A3M, A3A, A3U, A4U and Q06H program
CAUTION
When modifying a subprogram during main program run or vice versa, M9051, M9056 and
M9057 contacts should be used to disable the CHG instruction so that the CHG instruction may
not switch the currently running program to the program currently being corrected.
Always on
M9036 M9056 M9051
CHG
FEND
Always on
M9036 M9057 M9051
CHG
FEND
Main sequence program
Subsequence program

Mitsubishi MELSEC-A series Specifications

General

Brand	Mitsubishi
Model	MELSEC-A series
Category	Controller
Language	English