Mitsubishi Electric Melsec Q Series User Manual page 24

1
OVERVIEW
(8) Redundant system can be constructed
1
- 5 1.1 Features
(a) Redundancy is available for the QJ71PB92V.
By mounting the QJ71PB92V together with a redundant CPU, a redundant
system can be constructed.
Even if the QJ71PB92V detects an error, the control and standby systems are
switched each other continuing communications. (
(b) System switching is available when an error occurs in the QJ71PB92V or in
communication with a DP-Slave.
The systems can be switched when an error occurs in the QJ71PB92V or in
communication with a DP-Slave.
• When the QJ71PB92V detects a critical error
Control system
New standby system
Bus terminator
DP-Slave (QJ71PB93D)
Figure 1.2 When the QJ71PB92V detects a critical error
• When the QJ71PB92V detects a communication error of a DP-Slave
Control system
New standby system
Bus terminator
Communication
failure
Figure 1.3 When the QJ71PB92V detects a communication error of a DP-Slave
Standby system
Error in
QJ71PB92V
New control system
System switching
Tracking cable
ST1H-PB
RELEASE
RESET
PROFIBUS I/F
DP-Slave (ST1H-PB)
Standby system
New control system
System switching
Tracking cable
Section 4.8)
Continues communication
Bus terminator
ST1PSD ST1PDD
RUN ERR RUN ERR RUN ERR RUN ERR RUN ERR RUN ERR
SYS 11 21 11 21
AUX AUX
.
Continues communication
Bus terminator