Mitsubishi Electric MELSEC-A Series Manual page 145

4
REPLACEMENT OF THE MELSECNET/10 (PLC TO PLC NETWORK)
(3) Performance comparison of AJ71LP21G/AJ71QLP21G and QJ71LP21G
(MELSECNET/10 mode)
Item
Maximum
LX/LY 8192 points
number of link
LB 8192 points
points per
LW 8192 points
network
Maximum number of link
{(LY + LB)  8 + (2 × LW)}
points per station
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)
255 (Total number
of PLC to PLC
Maximum number of
networks and
networks
remote I/O
networks)
Maximum number of
9
groups
Number of stations
64 stations (Control station: 1, normal station: 63)
connected in one network
Applicable cable GI optical cable
Overall distance 30km
Distance between
GI optical cable: 2km
stations
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
• N:N communication (e.g. monitor, program up/download)
Transient transmission
• Dedicated link instruction
Number of occupied I/O 32 points per slot (I/O assignment:
points special 32 points)
Specifications
AJ71LP21G AJ71QLP21G
2000 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
QJ71LP21G
(MELSECNET/10 mode)
32 points per slot (I/O
assignment: intelli. 32
points)
: Partial change required, ×: Incompatible
Precautions for replacement
Network No.240 to No.250
cannot be set.
Alternate them with unused
network No.
For comparison of dedicated
link instruction, refer to
Section 4.6.2.
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