YOKOGAWA UTAdvanced Series, User Manual

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IM 05P07A01-01EN
Description of Ethernet Communication (Modbus/TCP) (for UT
Advanced with Ethernet Communication)
4
4.5 Ethernet-Serial Gateway Function
4.5.1 Overview
The Ethernet-serial gateway function is a function that reads/writes data from/to other
devices equipped with RS-485 serial communication function using the MODBUS/TCP
protocol via the UT75A/UT55A/UT35A/UP55A/UP35A.
With this function, the host computer can access the devices connected to the RS-485
serial communication line in the same way as to access the devices connected to
Ethernet.
*: VJET is the converter of YOKOGAWA. See the user’s manual for
VJET when using it.
Ethernet
RS-485
communication
Host computer
IP address [192.168.1.1]
RS-485 communication address = 01
IP address [192.168.1.2]
RS-485
communication address = 02
RS-485
communication address = 03
RS-485
communication address = 10
UT75A/UT55A/
UT35A/UP55A/
UP35A with
Ethernet
function or
VJET*
Device with Ethernet function
The UT75A/UT55A/UT35A/UP55A/UP35A operates as a gateway that changes the
MODBUS/TCP protocol received via network to the MODBUS/RTU protocol for the
serial devices connected to the RS-485 communication interface. Therefore, the devices
supporting the MODBUS/RTU protocol are required for the devices to be connected.
Note
When Ethernet communication is used, the RS-485 communication interface of the UT75A/
UT55A/UT35A/UP55A/UP35A is exclusively for the Ethernet-serial gateway function.
PCs and other host computers cannot access the UT55A/UT35A/UP55A/UP35A via this
RS-485 communication interface.