Chapter 7: Computer Link Function

7-2 FL-net

[1]Description of the FL-net

(1)The FL-net concept

FL-net is an FA control network that uses an Ethernet protocol. FL-net has a cyclic transfer function and a message transfer function. The basic concepts of the FL-net are as follows.

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1Ethernet protocols are used for communication (physically and as conceptual data links) between FA controllers.

2A UDP/IP scheme compatible with the Ethernet is used. It establishes the basic data transfer procedures.

3While using the basic data transfer methods above, FL-net guarantees data transfer within a specified time by managing and controlling (preventing conflicts) the access to communications by each node in the network.

The goal of the FL-net is to control devices such as programmable controllers (PC), robot controllers (RC), numeric control devices (CNC), and establish an FA control network that allows the exchange of data between personal computers.

The figure below shows the conceptual arrangement of the FL-net.

EWS

Personal

Personal Personal

Server

computer

computer computer

 

Information network (Ethernet)

Gateway

 

 

FL-net

 

 

 

PC

 

 

 

Image Robot

Nut

NC Printer BCR Personal ID

Graphic

controller

runner

Field network

computer

panel

 

 

 

 

Sensor

actuator

Note: BCR; Bar Code Reader, ID: ID controller

The FL-net concept

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