Mitsubishi Electric MELSEC-A Series Manual page 27

1
INTRODUCTION
(c) 2-tier system 3: System configuration example using local stations/remote I/O stations
MELSECNET/B
Twisted
M
L1 L2
MELSECNET/H
Optical loop
Network
1N 1 1M 4/2M
S P
1
1N 2
S
Coaxial bus
1M 4/2M
P
Network 1
1N 1 1N 2
S S
Twisted/Optical loop
R3
1M 4/2M
P
(Optical loop)
Network 1 (Twisted)
1N 1 1N 2
S S
Twisted/Coaxial bus
1M 4/2M
P
Network 1
(Twisted)
1N 1 1N 2
S S
System configuration precautions
Network
2R3
R
2
1) New installation: The installation has to
be changed for an optical loop system
or a coaxial bus system.
R
2) Composite system: As a mixture of a
Network 2
PLC to PLC network and a remote I/O
network is not allowed on the Q series,
2R3
the network has to be divided into two
networks having different network Nos.
For this reason, a separate network
module for the remote master station is
required.
2R3
R
Network 2
3) Wire-saving: Changing to a wire-
saving network by using CC-Link or
CC-Link/LT is also recommended for
remote I/O stations.
R
Network 2
(Coaxial bus)
2R3
1
- 10