Glossary · Automation fundamentals, platforms and components
Field level
Also known as: Field layer, Device level
German: Feldebene
In the automation pyramid, the field level is the lowest layer, containing sensors, actuators, field devices and I/O that interact directly with the physical process. It corresponds roughly to levels 0 and 1 of ISA-95 / IEC 62264.
- Automation components
In one sentence
The field level is the lowest layer of the automation pyramid, with sensors, actuators and I/O that interact directly with the process.
Example
At the field level, a flowmeter, a control valve and an IO-Link temperature sensor are connected to a distributed I/O station.
How it applies
- Engineering: Field devices connect via hardwired signals (4–20 mA, digital), fieldbuses, IO-Link or industrial Ethernet. Smart devices increasingly provide diagnostics and parameters, not just process values.
- Maintenance: Most failures in a plant occur at the field level: sensors, valves, cables and connectors.
- Documentation: Device lists, loop diagrams and installation drawings describe the field level. Operating manuals of field devices need clear instructions for installation, parameterization and replacement.
- Commissioning: Loop checks verify each field signal from the device to the controller and HMI, including ranges, units and alarm limits.
Field level vs. control level
The field level measures and acts; the Control level decides. Smart field devices with local logic blur this boundary, but responsibility for the control function should still be assigned clearly.