Product data
15
Introduction (continued)
Modicon
™
Quantum
™
Ethernet I/O
automation platform
Ethernet Hot Standby architectures
Types of Quantum
™
Ethernet I/O architecture (1) (continued)
Ethernet Hot Standby
The Unity Hot Standby system is used for demanding applications that require the
availability of the control/command system, as no interruption of the process can
be tolerated.
The Ethernet Hot Standby architecture helps to ensure global availability of the Hot
Standby CPU and Ethernet I/O devices.
At the heart of this architecture are two PLC racks (Primary and Standby) with
identical hardware congurations, based on 140CPU67p6p Unity Hot Standby
CPUs, connected via a high-speed ber optic cable.
The volume of data exchanged between the Primary and Standby PLCs can reach
1.5 MB depending on the CPU.
The Primary PLC executes the application program and controls the I/O, while the
Standby PLC remains in the background.
In the event that the primary PLC becomes inoperative, the standby system
switches over automatically, changing over execution of the application program
and control of the I/O to the Standby PLC with an up-to-date data context.
Once the changeover is complete, the Standby PLC becomes the Primary PLC.
Once the inoperative PLC has been repaired and reconnected to the standby
system, it takes the role of the Standby PLC.
The changeover is performed smoothly at the outputs and is completely transparent
to the process.
The Hot Standby system with Unity
™
Pro software increases productivity by
minimizing process downtime.
Hot Standby system based on Ethernet RIO architecture
The Hot Standby system based on the remote I/O (RIO) architecture is used for
sensitive processes that require an I/O control takeover time within the region of the
PLC scan time.
As the RIO drops are synchronized with the PLC CPU scan time, the CPU
changeover is carried out smoothly at the outputs, i.e. it is bumpless.
Maximum distance between each ConneXium managed switch:
100 m with copper medium b
2 km with multimode ber optic medium b
15 km with single mode ber optic medium b
Hot Standby system based on Ethernet DIO device architecture
In this type of Hot Standby architecture with no Ethernet RIO, the CRA Ethernet drop
adaptor is not required. Only a CRP Ethernet head adaptor is needed in each PLC
(Primary and Standby).
(1) Requires Unity Pro Extra Large software u V6.0.
(2) Please refer to the relevant product catalogs on our website www.schneider-electric.com.
(3) As well as the secondary ring, an Ethernet DIO device cloud can be connected to each switch.
Quantum Ethernet I/O Hot Standby architecture with Ethernet
DIO devices, with no CRA Ethernet drop adaptor
Hot Standby link
Ethernet network
Quantum
Ethernet I/O
(Standby
PLC)
Quantum Ethernet I/O
(Primary PLC)
Ethernet DIO device cloud (2)
Ethernet DIO (2)
RSTP
CRP
CRP
Managed
switches
Managed
switch
Managed
switches
Managed
switch
Long distance Quantum Ethernet I/O Hot Standby architecture
Ethernet RIO
Ethernet RIO
Ethernet RIO
Local HMI
(2)
Ethernet DIO device cloud (2)
Ethernet DIO (2)
Ethernet network
Ethernet network
Ethernet network
Fiber optic
Ethernet network
Hot Standby linkHot Standby link
Fiber optic
Ethernet network
Ethernet network
Quantum Ethernet I/O
(Standby PLC)
Quantum
™
Ethernet I/O
(Primary PLC)
RSTP
RSTP
RSTP
RSTP
RSTP
CRA
CRA
CRA
CRA
CRA
CRA
CRPCRP
(3)
(3)
(3)
Fiber optic
Ethernet network