Programmable Logic Controllers (PLC) in the packaging industry: An object oriented approach for developing control programs

Packaging automated industry is based on PLC control systems. Most of them are IEC 61131-3 PLC compliant. The standard was the first step to introduce Object Oriented Programming (OOP) features in the PLC based automation such as encapsulation in Function Blocks. Nevertheless, other major benefits of OOP such inheritance, or polymorphism weren´t defined. On the other hand, the standard was born with the aim of create a unique structure of PLC programs providing a way to exchange programs between several PLC brands. However this goal is far from being achieved. In this paper, a new approach to include these OOP benefits is proposed. Besides, programs developed within this framework can be adapted with minimum effort and maximum reliability to different packaging.