11.8 HMI displays with graphics capabilities and panel PCsIf displays with graphics capabilities are used, a graphic presentation of the plant situation on the latter is to be preferred to a textual presentation. End position switches, photoelectric barriers, etc. (including equipment identifier) and their logic states are to be shown in overview images of the plant. The logic states of individual protective devices, such as safety gates, safety photoelectric light barriers, emergency stop circuit-breakers, are to be clearly presented on a plant overview display. Fault messages and process signals are to be shown on a permanent display panel.