Mitsubishi Electric Melsec QJ71LP21 - Page 382

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MELSEC-Q
7 APPLICATION FUNCTIONS
(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]
Other station's
data received
from station
No. 1 or 2
Control stationStation No. 1 Communication error station
System A Control system
Standby system
Monitoring time
SB0049
OFF
ON
A communication
error occurs.
A system switching
request is issued.
System B Standby system
Control system
System A
CPU scan time
System switching
monitoring time
System switching time
12 3
4
Data sent from
station No. 2
to other station
5)
Cyclic data retention time
5 6
1)
Cyclic transmission delay timeCyclic transmission delay time
System B
CPU scan time
Data sent from
station No. 1 to
other station
1)0)
4)
5)
4)
0)