Mitsubishi Electric QJ71LP21 Reference Manual page 90

3 SPECIFICATIONS
Control system
Control system
Network
Standby system
Output holding time of remote I/O station
3 - 50
(3) System switching when the link cable disconnection occurs in the
host network module
If a communication error occurs due to link cable disconnection on the host
network module, it will considerably increase "data link monitoring time +
switching monitoring time".
Therefore the calculation formula is not affected by the CPU system switching
time and the switching time from the multiplexed remote master station to the
multiplexed remote sub-master station.
Multiplexed remote master station
standby system
Remote I/O station (R)
An error has occurred on the control system
standby system CPU
control system CPU
[Output holding time (Toh)]
Toh = 500 + K + Tc + Tsw + (Scan
K: Data link monitoring time (set up by the common parameters in the network
parameters) [ms]
Tc: Switching monitoring time (specify the setting range using SW0018)
[ms]
Tsw: Redundant CPU system switching time [ms]
Scan: Scanning time of the redundant CPU [ms]
POINT
For the CPU system switching time, refer to QnPRHCPU User's Manual
(Redundant System).
Multiplexed remote sub- master station
Standby system
Remote I/O station (R) Remote I/O station (R)
Scan
500
K
2) [ms]
control system
Tc
Tsw
Scan
Toh
MELSEC-Q
10ms
3 - 50