Mitsubishi MELSEC Q Series Programming Manual page 190

MC,MCR
MC
(1) If the execution command of the MC instruction is ON when master control is started, the
result of the operation from the MC instruction to the MCR instruction will be exactly as the
instruction (ladder) shows.
If the execution command of the MC instruction is OFF, the result of the operation from the
MC instruction to the MCR instruction will be as shown below:
High speed timer
Low speed timer
High speed retentive timer
Low speed retentive timer
Counter
Devices in OUT instruction
SET, RST
SFT
Basic,
Application
(2) Even when the MC instruction is OFF, instructions from the MC instruction to the MCR
instruction will be executed, so scan time will not be shortened.
(3) By changing the device designated by
number as often as desired.
(4) Coils from devices designated by
Further, using these same devices with the OUT instruction or other instructions will cause
them to become double coils, so devices designated by
instructions.
MCR
(1) This is the instruction for recovery from the master control, and indicates the end of the
master control range of operation.
(2) Do not place contact instructions before the MCR instruction.
(3) Use the MC instruction and MCR instruction of the same nesting number as a set.
However, when the MCR instructions are nested in one place, all master controls can be
terminated with the lowest nesting (N) number.
(Refer to the "Precautions for nesting" in the program example.)
Operation Error
(1) There are no operation errors associated with the MC or MCR instruction.
5-48
Device
Devices in the following instructions:
When a ladder with master control contains instructions that do not require any
contact instruction (such as FOR to NEXT, EI, DI instructions), the CPU module
executes these instructions regardless of the ON/OFF status of the MC instruction
execution command.
Device Status
Count value goes to 0, coils and contacts all go OFF.
Coils go OFF, but counter values and contacts all maintain
current status.
All turned OFF
Maintain current status
, the MC instruction can use the same nesting (N)
D
are turned ON when the MC instruction is ON.
D
should not be used within other
D