Mitsubishi Electric MELSEC-A Series Manual page 147

4
REPLACEMENT OF THE MELSECNET/10 (PLC TO PLC NETWORK)
Item
A1SJ71LR21
• Loop-back function due to error
detection or broken cable
• Diagnostic function for checking local
link lines
• Prevention of system down by
RAS function
switching the control station
• 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
AJ71LR21 AJ71QLR21
A1SJ71QLR21
Compatibility
QJ71BR11
(MELSECNET/10 mode)
• Diagnostic function for
checking local link
lines
• Prevention of system
down by switching the
control station
• Abnormal detection
using link special
relays and link special
registers
• Network monitoring
and various diagnostic
functions
32 points per slot (I/O
assignment: intelli. 32
points)
Precautions for replacement
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 4.6.2.
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