Mitsubishi Electric MELSEC-A Series Manual page 24

1
INTRODUCTION
(d) 3-tier system 1: System configuration example using local stations only
MELSECNET( II )
Coaxial loop
M
L1
L2/m
I1
I2
*1 As the transmission speed of MELSECNET/H is faster than MELSECNET(II), and as the transmission method is different,
the distance between stations and overall distance become shorter.
(e) 3-tier system 2: System configuration example using 2-tier local stations and 3-tier
remote I/O stations
MELSECNET( II )
Coaxial loop
M
L1
L2/m
r1
r2
*1 As the transmission speed of MELSECNET/H is faster than MELSECNET(II), and as the transmission method is different,
the distance between stations and overall distance become shorter.
1
- 7
MELSECNET/H
Coaxial bus
1M 4
P
L3 Network 1
1N 1 1N
S S
Network 2
I3
2N 1 2N
S
MELSECNET/H
Coaxial bus
1M 4
P
Network 1
L3
1N 1 1N
S S
Network 2
r3
2R1 2R2
System configuration precautions
1) Distance between stations: If this value
exceed the Q series specification values
when re-using the MELSECNET(II)
system cables, 3C-2V has to be changed
to 5C-2V.
2) Overall distance: If this value exceeds the
Q series specification value when
MELSECNET(II) system cables are re-
used, measures (e.g. adding a repeater
unit) are required.
2/2M 4 1N 3
P S
3) CPU: When replacing an integrated type
CPU, one new slot (32 points) is required.
4) Number of stations: When 65 modules
are connected, measures (e.g. dividing
2 2N 3
S S
into two or three networks of 32 modules
or less having a different network No.) are
required.
5) Duplex loop: When the transmission path
has to be duplexed, changes to an optical
loop system, etc. are required.
System configuration precautions
1) Distance between stations: If this value
exceed the Q series specification values
when re-using the MELSECNET(II)
system cables, 3C-2V has to be changed
to 5C-2V.
2) Overall distance: If this value exceeds the
Q series specification value when
MELSECNET(II) system cables are re-
used, measures (e.g. adding a repeater
unit) are required.
2/2M 1N 3
R S
3) CPU: When replacing an integrated type
CPU, one new slot (32 points) is required.
4) Number of stations: When 65 modules
are connected, measures (e.g. dividing
2R3
into two or three networks of 32 modules
or less having a different network No.) are
required.
5) Duplex loop: When the transmission path
has to be duplexed, changes to an optical
loop system, etc. are required.
*1
*1
*1
*1