Mitsubishi Electric Melsec A Series - 3.2 Performance Specifications Comparisons; 3.2.1 Module performance Compatibility comparisons

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REPLACEMENT OF MELSECNET (II) AND /B (REMOTE I/O NETWORK)
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3.2.1 Module performance Compatibility comparisons
(1) Comparison between MELSECNET (II) module (optical loop) and MELSECNET/H module
(optical loop)
(a) SI optical cable, H-PCF optical cable
: Compatible, : Partial change required, ×: Incompatible
3.2 Performance Specifications Comparisons
Item
Specifications
Compat-
ibility
Precautions for replacement
MELSECNET (II) module MELSECNET/H module
Optical loop
Optical loop
(QJ71LP21-25, QJ72LP25-25)
Maximum
number of
link points
per
network
X/Y
Max. 2048 points and max. number of
I/O points of CPU module on master
station
8192 points
B-
16384 points
(Remote master station  remote I/O
station: 8192 points, remote I/O station 
remote master station: 8192 points)
W
• (MELSECNET mode) 1024 points
• (MELSECNET II composite mode)
4096 points
16384 points
(Remote master station  remote I/O
station: 8192 points, remote I/O station 
remote master station: 8192 points)
Maximum
number of
link points
per
station
Master
station
• (MELSECNET mode) 1024 bytes
• (MELSECNET II composite mode)
First half: 1024 bytes
Remote master station  remote I/O
station
{(LY + LB)  8 + (2 × LW)} 1600 bytes
Remote
I/O
station
512 bytes
Remote I/O station  remote master
station
{(LX + LB)  8 + (2 × LW)} 1600 bytes
Maximum number of
I/O points per station
512 points 4096 points
Communication
speed
1.25 Mbps 25Mbps/10Mbps
Number of stations
connected in one
network
65 stations (Master station: 1, local
station + remote I/O station: 64)
65 stations (Remote master station: 1,
remote I/O station: 64)
Set the PLC to PLC network to
a separate network.
Applicable cable
SI optical cable
H-PCF optical cable
SI optical cable
H-PCF optical cable
Broad-band H-PCF optical cable
QSI optical cable
When using existing SI cables,
the distance between stations
may be shortened.
(Refer to Section 3.2.2.)
Overall distance 10km 30km
Distance between
stations
Refer to Section 3.2.2. Refer to Section 3.2.2.
To ensure the same distance
as before replacement, either
change the optical cable, or
install a gateway station
midway along existing cables.
Maximum number of
networks
-239
New MELSECNET/H
parameter (mandatory)
Communication
method
Half duplex bit serial method Token ring method
Nothing to be noted though the
communication method differs.
Transmission
method
Duplex loop
Modulation method
(Encoding method)
(Modulation method) CMI method (Encoding method) NRZI coding
Nothing to be noted though the
modulation method differs.
Transmission format HDLC standards (frame format)
Error control system
CRC (X
16
+X
12
+X
6
+1) and retry by a time over
RAS function
• Loop-back function due to error detection or broken cable
• Diagnostic function for checking local link lines
Number of occupied
I/O points
(Master station)
CPU integrated type: 0 point
Standalone:32 points per slot (I/O
assignment: special 32 points)
(Master station)
32 points per slot (I/O assignment: intelli.
32 points)
When the master station is
replaced from a CPU
integrated type, one new slot
(32 points) is required.