Chapter 1. Introduction
24
PACSystems* RX3i & RSTi-EP PROFINET IO-Controller User Manual
GFK-2571N
1.6.9
Systems that use Hot Standby CPU Redundancy
Figure 14 shows a Hot Standby CPU Redundancy system that uses a PROFINET I/O network with
MRP ring topology. Use of MRP ring topology is recommended because it eliminates the I/O network
as a single point of failure. If elimination of a single point of failure is not required, a star topology can
be used.
These systems are described in the
PACSystems Hot Standby CPU Redundancy User’s Manual,
GFK-2308F or later.
1.6.9.1
Hot Standby CPU Redundancy Network with MRP Ring Topology
I
O
I
O
I
O
I
O
P
2
P
1
P
N
S
P
S
C
P
U
R
M
X
R
M
X
P
N
C
E
T
M
P
S
C
P
U
R
M
X
R
M
X
P
N
C
E
T
M
I
O
I
O
I
O
I
O
P
2
P
1
P
N
S
Redundancy Links
RX3i
Primary
Controller
RX3i
Secondary
Controller
HMI
PME
HMI
Historian
Redundant IP
I
O
I
O
I
O
I
O
P
2
P
1
P
N
S
I
O
I
O
I
O
I
O
P
2
P
1
P
N
S
P
S
P
S
Remote IO Device
Remote IO Device
Remote IO Device
Remote IO Device
Supervisory Ethernet Network
(Up to 8 separate networks
allowed)
PROFINET I/O Network
RING
(Up to 4 separate networks allowed)
Figure 14: RX3i Hot Standby CPU Redundancy Network with MRP Ring Topology
