Description - WAGO -I/O-SYSTEM 750 User's Installation And Configuration

18 • Fieldbus coupler 750-342

Description

3.1.1 Description
The fieldbus coupler 750-342 displays the peripheral data of all I/O modules in
the WAGO-I/O-SYSTEM 750 on ETHERNET.
All sensor input signals are grouped in the coupler (slave) and transferred to
the higher ranking controls (master) via the fieldbus. Process data linking is
performed in the higher ranking controls. The controls put out the resulting
data to the actuators via the bus and the node.
To be able to transmit process data via ETHERNET, the coupler supports a se-
ries of network protocols. Process data are exchanged with the aid of the
MODBUS/TCP protocol.
Once the ETHERNET TCP/IP fieldbus coupler is connected, the coupler de-
tects all I/O modules connected to the node and creates a local process image
on this basis, which can be a mixed arrangement of analog (word-by-word data
exchange) and digital (bit-by-bit data exchange) modules.
The local process image is subdivided into an input and an output data area.
The data of the analog modules are mapped into the process image in the order
of their position downstream of the bus coupler.
The bits of the digital modules are grouped into words and also mapped into
the process image as soon as mapping of the analog modules is completed.
When the number of digital I/O's exceeds 16 bits, the coupler automatically
starts the next word.
Also note that all process images start at WORD 0.
Information on configuration, status and the I/O data of the fieldbus node are
stored in the fieldbus coupler as HTML pages. These pages can be seen via a
standard WEB browser by typing the IP address, that you assigned the coupler,
into the Address field of your web browser.
Modular I/O System
ETHERNET TCP/IP