Mitsubishi Electric MELSEC Q Series Reference Manual page 261

7 APPLICATION FUNCTIONS
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(3) Startup of a multiplexed remote sub-master station only
(a) By setting the same parameters as the multiplexed remote master station,
the multiplexed remote sub-master station continues the control of the
remote I/O stations if it is powered on and off while controlling the remote
I/O stations.
However, the outputs of the remote I/O stations are cleared when the
multiplexed remote sub-master stations resumes the controls.
POINT
Except items "Network type" and "Starting I/O No.", set the parameter of the
multiplexed remote sub-master station same as the multiplexed remote master
station.
Multiplexed remote
master station
Remote I/O station Remote I/O station
REMARKS
If the multiplexed remote master station has returned to the system and performs
sub-master operation, the multiplexed remote master station controls the remote I/O
stations.
(b) This function enables the remote I/O stations to be controlled by the
multiplexed remote sub-master station alone if the multiplexed remote
master station is not made ready at a system startup.
Without multiplexed
remote master station
Remote I/O station Remote I/O station
Multiplexed remote
sub-master station
Power off to on
When control is resumed, outputs are cleared.
Remote I/O station
Multiplexed remote
sub-master station
Remote I/O station
MELSEC-Q
Set the same parameters as the
multiplexed remote master station.
Set the same parameters as the
multiplexed remote master station.
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