The field level is also referred to as the sensor or actuator level and represents the lowest level of the automation pyramid in industrial production systems. Field levels are in place to quickly collect basic data in the form of binary signals. See Fig. 1 Field level
Each level transitions fluidly to the next and is responsible for carrying out specific tasks, for which special methods of analog and digital data transmission and processing have been developed.
Centrifugal pumps and valves are located at field level and are therefore considered field devices, or intelligent field devices, depending on the extent to which electronics have been integrated (see Communications system).