Fieldbus
9836 3123 01 227 (428)
Icon file
Contact the local Atlas Copco service representative to get a copy of the Icon file for Power Focus. This
file can be used to have a Power Focus Icon in the PLC configuration SW. File name: pf3intb.ico
15.8.4 ModBusPlus
ModBusPlus is a local area network system designed for industrial control and monitoring applications,
developed by Modicon, Inc. The network enables programmable controllers, host computers and other
devices to communicate throughout plants and substations. ModBusPlus transfers fast data for motor
controllers, MMI, I/O units and other industrial equipment. ModBusPlus has an international user
organization called Modicon Inc.
General technical questions regarding the fieldbus should be addressed to the local ModBusPlus User
Group in the first instance.
A contact address list is available from the ModBusPlus Internet site http://www.modicon.com.
Physical interface
ModBusPlus uses one differential line (RS-485 twisted pair) and shield.
Token Bus Structure, virtual token ring.
Shielded copper cable, one twisted pair.
The bus signals are separated from the other electronics with a transformer according to ModBusPlus
interface description.
Module is based on chip-set and software from Modicon Inc.
Mechanical overview
ModBusPlus module is a host device. This host device can be read and written to from another
ModBusPlus host device or controller. ModBusPlus module does not initiate any point-to-point
communication to other nodes, it only responds to incoming commands. It can although broadcast global
data to all nodes on the network.
Protocol and supported functions
ModBusPlus has two ways of exchanging data. One through fast cyclic I/O data called global data and one
through a somewhat slower ModBusPlus protocol for point-to-point parameter data transfer. The
To Next Page
Loading...
Need help?
General
