Redundant System Support Function - Mitsubishi Electric Melsec Q Series User Manual

4
FUNCTIONS

4.8 Redundant system support function

When the control system CPU or the QJ71PB92V detects an error, the control and
standby systems are switched each other to continue communications.
(1) Redundant system operation overview
When the CPU or QJ71PB92V in the control system detects an error, system
switching is performed to continue communications.
Bus terminator
DP-Slave (QJ71PB93D)
Control system
New standby system
Bus terminator
DP-Slave (QJ71PB93D)
QJ71PB92V
FDL address 0
Control system
*1
Error
detected
Tracking cable
QJ71PB92V
FDL address 0
FDL address 1
Executes system
switching
Tracking cable
Figure 4.27 Redundant System Operation Overview
* 1 For conditions for making a system switching request (system switching methods), refer to (2) in
this section.
4.8 Redundant system support function
QJ71PB92V
FDL address 1
Standby system
.
DP-Slave (ST1H-PB)
QJ71PB92V
Standby system
FDL address 1
FDL address 0
New control system
*1
.
DP-Slave (ST1H-PB)
Bus terminator
Continues communication
Bus terminator
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