User manual

105G Wireless Gateway User Manual
Elpro_man_105g_1.18.doc Page 10
This document assumes the reader is familiar with the operation of the 105U I/O modules - for
further information; please refer to the User Manuals for these products.
The 105U-G is referred to as the 105G for the rest of this document, to clearly differentiate
from normal 105U I/O modules.
Model information:
105G-MD1 Modbus Master & Slave / DF1 interface
105G-PR1 Profibus-DP Slave interface
105G-PR2 Profibus-DP Master interface
105G-ET1 Ethernet interface - Modbus TCP, Ethernet IP, FTP, HTML, Email
105G-DE1 DeviceNet Slave interface
105G-M+1 Modbus Plus Slave interface
The same ordering codes apply to the 105U-G product range.
1.1.1 Modbus / DF1 105G
The 105G-MD1 can be configured for Modbus master interface, Modbus slave, or DF1.
Modbus is a Master-Slave protocol originally developed by Modicon (now part of the Schneider
group). It became a popular interconnect protocol with many equipment manufacturers. One
Modbus master controls the Modbus network communications, which can comprise up to 250
Modbus slave devices. The Modbus master can read or write I/O values to/from Modbus slaves.
The 105G can be configured as either Modbus Master or Modbus Slave. The variation of
Modbus supported by the 105G is “Modbus RTU” (also known as “Modbus binary”).
DF1 is an Allen-Bradley protocol (Allen-Bradley is now part of the Rockwell Automation
group). DF1 offers both full-duplex (point to point) and half-duplex (multidrop) operation. The
105G only supports the full-duplex operation - this is the default DF1 mode on most equipment.
DF1 full-duplex is a “peer-to-peer” protocol. That is if configured as an “Initiator” it will initiate
commands to the other devices, if configured as a “Responder” it will respond to commands
from the”Initiator”.
The 105G-MD1 has two serial connections - RS232 and RS485, on the bottom end plate of the
module. The serial port provides both RS232 and RS485 hardware connections, however both
connections are paralleled internally - both connections cannot be used at the same time. Either
RS232 or RS485 can be used for Modbus communications, however only the RS232 port can
be used for DF1. The serial port must be configured to suit the host device. Serial data rates
between 1200 and 19200 baud may be selected, and character types with 7 or 8 data bits,
even/odd/none parity, and 1 or 2 stop bits may be selected.
The Modbus/DF1 105G has 4300 general-purpose I/O registers. Each discrete, analog and pulse
I/O point takes up one register.
1.1.2 Profibus 105G
The Profibus 105G provides Profibus-DP Slave functionality according to EN 50170. Profibus
is a popular automation fieldbus that originated in Germany and is used extensively by Siemens
and other automation suppliers.
The Profibus connection on the 105G is optically isolated RS485 using an on-board DC/DC