Virtual simulators use the actual code from both the control logic and the human machine interface (HMI).
The control logic is “wrapped” in a software envelope, allowing it to run on a PC instead of the plant’s hardware controller. This results in precisely the same functionality as the plant’s actual controls. In addition, the simulator HMI screens use the actual DCS graphics, which are set up to run on PCs. In both functionality and appearance, the HMI on the simulator is an exact reproduction of the actual graphics in the plant
Fully Emulated System
Fully emulated systems use an emulation of both the control logic and the operator interface. Emulation is achieved by translating the plant control logic and graphics into the simulator environment, effectively reproducing the functional operation of the actual controls and the graphic interface of the HMI.