In order to check whether a control software works as desired, tests are necessary. With the help of virtual commissioning (VC), more and more companies are starting the testing activities even before the real integration and commissioning: They connect the real control hardware and software with a digital model of the plant. With the help of this so-called hardware-in-the-loop (HiL) setup, the behavior of the plant can be simulated in control real time, and the entire system can be subjected to both a good and a bad case test much earlier.
Indispensable acceptance tests on the real system at the manufacturer's (factory acceptance test) or at the customer's (site acceptance test) can thus be completed much faster. While the good case tests are aimed at checking the performance and functionality required by the customer, the bad case tests test the reliability and robustness of the software by checking the reaction of the control software in explicit danger and fault situations.