Mitsubishi Electric Melsec QJ71LP21 Reference Manual page 382

7 APPLICATION FUNCTIONS
Station No. 1 Control station
OFF
SB0049
1
System A
CPU scan time
Data sent from
station No. 1 to
0)
other station
System A Control system
System B Standby system
System B
CPU scan time
Data sent from
station No. 2
to other station
Other station's
data received
from station
No. 1 or 2
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(3) Cyclic data retention time for system switching requesting from a
network module (host station)
Use the following expression to calculate the cyclic data retention time in the
case of system switching requesting from a network module (host station).
K : Monitoring time [ms]
Tc : System switching monitoring time [ms]
Tsw : Redundant CPU system switching time [ms]
SS : Redundant CPU scan time [ms]
A communication
error occurs.
Communication error station
Monitoring time
2
1)
Cyclic transmission delay time
0)
ON
A system switching
request is issued.
System switching
monitoring time
4
3
Standby system
1)
Cyclic data retention time
MELSEC-Q
Control system
System switching time
5
4)
Cyclic transmission delay time
4)
6
5)
5)
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