Mitsubishi Electric Melsec A Series - Page 173

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REPLACEMENT OF THE MELSECNET/10 (REMOTE I/O NETWORK)
5
3) Performance comparison of AJ71LP21G/AJ71QLP21G and QJ71LP21G
: Compatible, : Partial change required, × : Incompatible
*1 Remote master station  remote sub-master station, remote I/O station: 8192 points
Remote sub-master station, remote I/O station  remote master station: 8192 points
*2 The remote master station includes the multiplexed remote master station and multiplexed remote sub-master station.
*3 For the multiplexed remote I/O network, one station in 32 stations of the remote I/O station is used for the multiplexed
remote sub-master station.
Item
Specifications
Compatibility Precautions for replacement
AJ71LP21G AJ71QLP21G QJ71LP21G
Maximum number
of link points per
network
LX/LY 8192 points
LB 8192 points
16384 points
*1
LW 8192 points
16384 points
*1
Maximum number of link
points per station
<Remote master station 
remote I/O station>
{(LY + LB) 8 + (2 × LW)}
1600 bytes
<Remote I/O station 
remote master station>
{(LY + LB) 8 + (2 × LW)}
1600 bytes
<Remote master station  remote I/O station>
*2
{(LY + LB) 8 + (2 × LW)} 1600 bytes
<Remote I/O station  remote master station>
*2
{(LY + LB) 8 + (2 × LW)} 1600 bytes
<Multiplexed remote master station  multiplexed
remote sub-master station>
{(LY + LB)  8 + (2 × LW)} 2000 bytes
Communication speed 10Mbps
Communication method Token ring method
Synchronous type Frame synchronization method
Encoding method NRZI coding (Non Return to Zero Inverted)
Transmission method Duplex loop
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.
Number of stations connected
in one network
65 stations (Remote master station: 1, remote I/O station: 64)
*3
Applicable cable GI optical cable
Overall distance 30km
Distance between stations GI optical cable: 2km
Error control system
CRC (X
16
+X
12
+X
5
+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
• Abnormal detection using link special relays and link special registers
• Network monitoring and various diagnostic functions
Transient transmission
• Monitor, program up/download with peripheral
device
• Dedicated link instruction
• Available for Intelligent function module (only
AJ71QLP21G)
• 1:1 communication
(Monitor, program up/
download)
• Dedicated link
instruction
For comparison of dedicated
link instruction, refer to Section
5.1.7.
Number of occupied I/O
points
32 points per slot (I/O assignment: special 32 points)
32 points per slot (I/O
assignment: intelli. 32
points)