Flexitron Webdyn WebdynModbus - Configuring and Declaring Modbus Slave Devices

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If the installation uses RS485 wiring, the gateway can be placed at the end or in the middle of the
communication bus. To ensure correct operation of the RS485 communication bus, it must be terminated
at both ends using a 120 ohm terminator.
Depending on the positioning of the gateway on the bus, this terminator must be enabled or disabled via
a pair of jumpers (JMP4 and JMP1) tted inside the casing.
See the documentation for the Modbus devices for details of their connections and wiring.
7.2 Conguring and Declaring Modbus Slave Devices
The choice between RS232, RS485 2-wires, RS485 4-4wires, or Ethernet is exclusive. Consequently, all
the Modbus equipments connected to the WebdynModbus have to use the same interface and must be
congured as before. Only the slave’s address(es) must be unique, thus allowing their identication on
the bus.
The discovery of Modbus devices is impossible. Thus, every device present on the bus must be declared
in the prexID_daq.ini le. This conguration is done via the FTP server. The le prexID_daq.ini must
contain the parameters listed below: