20 Programmable logic controller
A programmable logic controller (PLC) is a digital device adapted for control of processes which require high reliability, ease of programming and realtime responses. Such functionality has long since replaced hardwired relays, timers and sequencers which would be required to complete various tasks.
Programmable logic controllers usually had to conform to IEC 611313 standard which defines four programming languages: function block diagram (FBD), ladder diagram (LD), structured text (ST) and sequential function chart (SFC). This standard does not support distributed control systems therefore IEC 61499 standard was published in 2005. The standard is considered an extension of IEC 611313 standard.
WCC Lite supports PLC functionality while conforming to specifications of IEC 61499 standard.
20.1 IEC 61499
IEC 61499-1 defines the architecture for distributed systems. In IEC 61499 the cyclic execution m...
20.2 4Diac framework
The PLC functionality in the WCC Lite is implemented using Eclipse 4diac framework, consisting ...
20.3 Example project
The best way to understand basics of 4Diac and WCC Lite collaboration is through an example proje...
20.4 Configuring data endpoints
To use WCC Lite as a programmable logic controller, it needs to be configured in a particular way...
20.5 Debugging an IEC 61499 application
After a project has been built and binded to an existing Excel configuration, a user would normal...
20.6 Generating and uploading FORTE logic file
After the PLC design is finished and debugged, such design can be compiled into FBOOT file and up...
20.7 Distributed control application
IEC 64199 standard introduced requirements for a distributed control. This means that multiple de...