Translation of Extended Petri Net Model into Ladder Diagram and Simulation with PLC

Modelling and simulation can significantly help with the teaching and learning of PLC programming, training of the operators and maintaining personal, developing automated systems and diagnosis of the systems' operation. The basic idea of the presented research and development was to use PLC programming tool for modelling a discrete mechatronic system and simulate its operation on industrial PLC or on emulation of PLC on the PC computer. For the realization of the idea the extensions of the basic Petri net theory (EPN) and direct translation of the EPN model into the ladder diagram were elaborated, which enabled the use of the EPN model for simulation on PLC Furthermore, the building blocks of EPN model were developed within the programme for discrete simulation, which enable building and verification of an EPN model of the observed system within the programme for discrete simulation before its implementation. The primary test of the method and the usability verification of the basic idea show that the method is applicable for teaching and learning of PLC programming and can also be used for an advanced developing and testing of PLC programmes. (C) 2009 Journal of Mechanical Engineering. All rights reserved.