Mitsubishi Electric Melsec A Series - Page 146

REPLACEMENT OF THE MELSECNET/10 (PLC TO PLC NETWORK)
4 - 5
4
(4) Performance comparison of AJ71LR21/A1SJ71LR21/AJ71QLR21/A1SJ71QLR21 and
QJ71BR11 (MELSECNET/10 mode)
: Compatible, : Partial change required, ×: Incompatible
Item
Specifications
Compatibility Precautions for replacement
AJ71LR21
A1SJ71LR21
AJ71QLR21
A1SJ71QLR21
QJ71BR11
(MELSECNET/10 mode)
Maximum
number of link
points per
network
LX/LY 8192 points
LB 8192 points
LW 8192 points
Maximum number of link
points per station
{(LY + LB)  8 + (2 × LW)} 2000 bytes
Communication speed 10Mbps
Communication method Token ring method Token bus method
Nothing to be noted though
the communication method
differs.
Synchronous type Frame synchronization method
Encoding method Manchester code
Transmission method Duplex loop Single bus
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.
Transmission format HDLC standards (frame format)
Maximum number of
networks
255 (Total number
of PLC to PLC
networks and
remote I/O
networks)
239 (Total number of PLC to PLC networks
and remote I/O networks)
Network No.240 to No.250
cannot be set.
Alternate them with unused
network No.
Maximum number of
groups
9
Number of stations
connected in one network
64 stations (Control station: 1, normal
station: 63)
32 stations (Control
station: 1, normal station:
31)
Normal stations up to 31
stations can be used on a
coaxial bus system. To use 32
normal stations or more, using
an optical loop system is
recommended.
Applicable cable 3C-2V, 5C-2V, 5C-FB
Overall distance
3C-2V: 19.2km
5C-2V, 5C-FB: 30km
3C-2V: 300m
5C-2V, 5C-FB: 500m
Either use an A6BR10/
A6BR10-DC type repeater
unit, or use an optical loop
system.
Distance between
stations
3C-2V: 300m
5C-2V, 5C-FB: 500m
Error control system
CRC(X
16
+ X
12
+ X
5
+ 1) and retry by a time over