2 - 3
MELSEC-F
SYSTEM CONFIGURATIONS2
2 - 3
(2) Connection using the 10BASE-T
Use devices that satisfy the standards of IEEE802.3 and 10BASE-T.
• Shielded twisted pair cable (STP cable), category 3 (4, 5)
* Straight cables can be used.
(Correct operation is not guaranteed if a crossed cable is used to connect to
an external device via the 10BASE-T of the Ethernet module. However, it is
possible to use crossed cables to connect two Ethernet modules for data
communication or to connect an Ethernet module.)
•RJ45 plug
• 10Mbps hub
POINT
• During the high-speed communication (100 M bps) via 100BASE-TX
connection, a communication error may occur due to the effect of high
frequency noise from devices other than PLC in a given installation
environment.The following describes countermeasures on the FX
3U-ENET-L
side to prevent the effect of high frequency noise for construction of a network
system.
(1) Wiring connection
• Do not bundle the twisted pair cables with the main circuit and power wires,
and do not install them close to each other.
• They should be installed at least 100 mm (3.94 in) away from each other.
• Make sure to place the twisted pair cables in a duct.
(2) Communication method
• Data communication with an external device is performed using TCP/IP
communication.
• Increase the number of communication retries as necessary.
[When the error cannot be solved]
• Communication is performed at a data transmission rate of 10 M bps by
changing the connection hub for the FX
3U-ENET-L to a hub capable of
handling 10 M bps.
External device
Twisted pair cable
Hub
* Up to 4 levels are allowed
for cascade connection
Ethernet module