Mitsubishi Electric QJ71LP21 Reference Manual page 189

7 APPLICATION FUNCTIONS
Link special relays used to confirm operating status of multiplexed remote master station
Number
SB0071 Remote master station baton pass status
SB0075 Remote master station cyclic transmission
status
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(c) Switching of multiplexed remote master station operation
When the multiplexed remote master station has returned to system, it can
be switched to master operation in the following procedure.
1) The multiplexed remote sub-master confirms that the multiplexed
remote master station has returned to the system by checking the link
special relay SB status.
2) The multiplexed remote sub-master station switches from master
operation to sub-master operation by operating the link special relay
SB.
3) The multiplexed remote master station switches to master operation
when the multiplexed remote sub-master station switches to sub-
master operation.
Multiplexed remote
master station
Sub-master operation
Remote I/O station
Multiplexed remote
master station
Master operation
During switching, outputs are held.
Remote I/O station
Name
Multiplexed remote
sub-master station
Master operation
Remote I/O station Remote I/O station
SB14 of multiplexed remote sub-master station: ON
Multiplexed remote
sub-master station
Sub-master operation
Shift of control right
Remote I/O station Remote I/O station
Indicates the baton pass status of the master station.
OFF : Master station baton pass normal
ON : Master station baton pass abnormal
Indicates the cyclic transmission status of the master station.
OFF : Master station cyclic transmission normal
ON : Master station cyclic transmission abnormal
MELSEC-Q
Description
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