Case study: Palladio-based modular system for simulating PLC performance

Modern facilities controlled by programmable logic controllers (PLC) have to fulfill a broader range of tasks and meet higher performance requirements than a few years ago. They have to cope with their basic control tasks as well as communicating with each other or external systems. The selection of an appropriate performance class during the early development phases is based on the experience of a developer or expensive and time consuming tests. In this paper, we present an approach to simulate the PLC and its environment to predict the CPU utilization. For this purpose, the PLC and its internal and external influences on the CPU utilization have been modeled with Palladio. Based on the simulation results of different usage scenarios, the developer is now able to choose a fitting performance class without conducting expensive tests.