Mitsubishi Electric MELSEC-A Series Manual page 174

5
REPLACEMENT OF THE MELSECNET/10 (REMOTE I/O NETWORK)
4) Performance comparison of AJ71LR21/A1SJ71LR21/AJ71QLR21/A1SJ71QLR21 and
QJ71BR11
Item
A1SJ71LR21
LX/LY 8192 points
Maximum number
of link points per LB 8192 points
network
LW 8192 points
<Remote master
station  remote I/O
station>
{(LY + LB) 8 + (2 ×
Maximum number of link LW)}
points per station <Remote I/O station
 remote master
station>
{(LY + LB) 8 + (2 ×
LW)}
Communication speed 10Mbps
Communication method Token ring method
Synchronous type Frame synchronization method
Encoding method Manchester code
Transmission method Duplex loop
Transmission format HDLC standards (frame format)
255 (Total number of
Maximum number of PLC to PLC networks
networks and remote I/O
networks)
Number of stations connected 65 stations (Remote master station: 1, remote
in one network I/O station: 64)
Applicable cable 3C-2V, 5C-2V, 5C-FB
3C-2V: 19.2km
Overall distance
5C-2V, 5C-FB: 30km
3C-2V: 300m
Distance between stations
5C-2V, 5C-FB: 500m
Error control system
CRC(X
• Loop-back function due to error detection or
broken cable
• Diagnostic function for checking local link
lines
RAS function
• Abnormal detection using link special relays
and link special registers
• Network monitoring and various diagnostic
functions
• Monitor, program up/download with
peripheral device
Transient transmission • Dedicated link instruction
• Available for Intelligent function module
(only AJ71QLR21/A1SJ71QLR21)
Number of occupied I/O 32 points per slot (I/O assignment: special 32
points points)
5
- 8
Specifications
AJ71LR21 AJ71QLR21
A1SJ71QLR21
<Remote master station  remote I/O station>
{(LY + LB) 8 + (2 × LW)}
<Remote I/O station  remote master station>
1600 bytes
{(LY + LB) 8 + (2 × LW)}
<Multiplexed remote master station  multiplexed
remote sub-master station>
{(LY + LB)  8 + (2 × LW)}
1600 bytes
239 (Total number of PLC to PLC networks and
remote I/O networks)
16 12 5
+ X + X + 1) and retry by a time over
: Compatible,
Compatibility
QJ71BR11
*1
16384 points
*1
16384 points
*2
1600 bytes
*2
1600 bytes
2000 bytes
Token bus method
Single bus
33 stations (Remote master
station: 1, remote I/O station:
*3
32)
3C-2V: 300m
5C-2V, 5C-FB: 500m
• Diagnostic function for
checking local link lines
• Abnormal detection using
link special relays and link
special registers
• Network monitoring and
various diagnostic
functions
• 1:1 communication
(Monitor, program up/
download)
• Dedicated link instruction
32 points per slot (I/O
assignment: intelli. 32 points)
: Partial change required, × : Incompatible
Precautions for replacement
Nothing to be noted though the
communication method differs.
The loopback function and
multiplex transmission function
cannot be used on a coaxial bus
system. To use the functions,
using an optical loop system is
recommended.
Network No.240 to No.250 cannot
be set.
Alternate them with unused
network No.
Normal stations up to 32 stations
can be used on a coaxial bus
system. To use 33 normal stations
or more, using an optical loop
system is recommended.
Either use an A6BR10/A6BR10-
DC type repeater unit, or use an
optical loop system.
The loopback function cannot be
used on a coaxial bus system. To
use the loopback function, using
an optical loop system is
recommended.
For comparison of dedicated link
instruction, refer to Section 5.1.7.