A process control system (1) comprises at least one process control computer (2) and field units (4) connected thereto via a bus system. An, in particular, intrinsically safe data transmission device (5) is connected between the process control computer and the assigned field units. This data transmission device comprises a data adaptation device (6) and a data distributing device (7). In order to be able to connect more field units per data adaptation device while simultaneously reducing the costs per field unit, the data adaptation device (6) and its assigned supply devices (8) have an explosion-proof design, and each supply device is connected to the data distributing devices via an explosion-proof line, whereby these data distributing devices or field units connected thereto have a barrier device for limiting the applied power.