Mitsubishi Electric Melsec QJ71LP21 Reference Manual page 275

7 APPLICATION FUNCTIONS
Control data setting instruction
Sent data setting instruction
Sending instruction
When designating a target station number, provide an interlock between
SW01FC to SW01FF (redundant system status) for judging whether the
target station is a control system.
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(e) Program example 3 (when specifying a target station to execute an
instruction to the redundant system)
When the target station is in a redundant system, the SEND instruction
must be executed after judging whether it is a control system.
If the target station is on the standby system, the RECV instruction is not
executed and the target station saving channel is not available.
The program example shown below is an interlock example for sending
data from station number 3 of network number 7 to the control system of
the redundant system made up of station numbers 1 and 2 of the same
network.
Processing program at send completion
Processing program at normal completion
Processing program at abnormal completion
With arrival confirmation/set clock data
Channel used by host station
Target station saving channel (logical channel number)
Target station network number
Target station number (when station No. 1 is a control system)
Target station number (when station No. 2 is a control system)
Arrival monitoring time (20s)
Sent data length (four words)
Sent data
Number of resend times
Reading error codes, etc.
MELSEC-Q
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