Mitsubishi Electric MELSEC iQ-RJ71EN71 User Manual page 230

Precautions
• When using the control system IP address, set connections separately for system A and B IP addresses. When the control
system IP address and IP addresses of systems A and B are used together for the same connection, loss of data, data
arrival order interchange, and others may be occur.
• Even when the control system IP address is used, the IP address on the programmable controller side shown in "External
Device Configuration" under "Basic Settings" displays the IP address set in "Own Node Settings" under "Basic Settings".
• Do not set the control system IP address to the IP address in "PLC side I/F" of the "Specify Connection Destination
Connection" window. Even when the control system IP address is set, if system switching occurs during connection, the
new control system cannot be tracked.
• In TCP/IP communications, the control system IP address can be used only when the Ethernet-equipped module side is set
as Passive open. When it is set as Active open, use the IP address of system A or B.
• In UDP/IP communications, the control system IP address can be used only when the Ethernet-equipped module receives
data.
• When systems are switched, if communication using the control system IP address cannot be performed normally, perform
the processing to update the ARP table of the external device.
• If the external device does not have a function to update the ARP table when receiving a GARP, it cannot track the new
control system at the time of system switching, and communication becomes impossible until the ARP table of the external
device is updated. The following table lists modules with function to update the ARP table when receiving a GARP.
Applicable module
MELSEC iQ-R series
MELSEC-Q series
MELSEC-L series
For whether an external device not manufactured by Mitsubishi supports a function to update the ARP table
when receiving a GARP, check the manual or specifications for the relevant external device.
1 FUNCTIONS
228
1.17 Redundant System Function
Process CPU (redundant mode)
RJ71EN71
QJ71E71-100
LJ71E71-100
Applicable version
Firmware version of "04" or later
Firmware version of "12" or later
Serial number (first five digits) of "12062" or
later
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