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MELSEC-F
COMMUNICATION PROCEDURE
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5.2.3 Re-initialization
Re-initialization is performed in order to place the Ethernet module into its startup
status without actually restarting the PLC.
Re-initialization of the Ethernet module can be performed in a sequence program.
The purposes of and how to program the re-initialization of the Ethernet module are
explained below.
NOTE
When FX Configurator-EN is being used, re-initialization can be performed after
downloading the parameters.
However, if it is connected to the Ethernet module via Ethernet, re-initialization
cannot be performed.
Re-initialize from the sequence program.
(1) Purposes of performing re-initialization
(a) To update address information of an external device maintained by the
Ethernet module
The Ethernet module maintains the IP address of the external device with
which it has been communicating and the corresponding Ethernet address
(MAC address). This is done in order to prevent other devices from
accessing the PLC illegally using the IP address of an external device with
which communication was performed normally. (*1)
For this reason it is necessary to re-initialize in order to clear the address
information of the external device maintained by the Ethernet module in case
a module or board on the external device side has been replaced due to
failure.
*1 Ethernet address is unique to a device. No devices share the same
Ethernet address.
(b) To change the IP address of the Ethernet module of the local station
If the system is changed, it is possible to restart communication with external
devices by changing the IP address (for the Ethernet module of the local
station) in the operation settings (see Section 4.6).
(c) To change the communication condition setting values
It is possible to restart communication with external devices by changing the
communication conditions in the operation settings (see Section 4.6).
