|
|
Function
PROFINET IO is used to control sensors and actuators using a central controller in production engineering.
A PROFINET IO system is assembled from the following devices:
- An IO Controller is a controller, typically a PLC, CNC, robot control or Motion Controller, that controls the automation task. Compared to PROFIBUS, an IO Controller is a Thin (from Thin/Client).
- An IO Device is a distributed field device which is linked via PROFINET IO. It is controlled by an IO Controller. An IO Device can consist of several modules and submodules. All data to be exchanged are assigned slots and subslots for the purpose of addressing. These are defined in the General Station Description (GSD) file. ET 200 distributed I/O or a SINAMICS drive are examples of PROFINET IO devices. Compared to PROFIBUS, an IO Device is a Client (from Thin/Client).
- An IO Supervisor is typically a programming device, a PC or an HMI device for commissioning or diagnostics. It features an engineering tool, which can be used to parameterize and diagnose individual IO devices. Compared to PROFINET, this would be a Class-2-Thin in terms of function (from Thin/Client).
PROFINET IO provides protocol definitions for the following functions:
- Cyclic transmission of IO data
- Acyclic transmission of alarms which require acknowledgement
- Acyclic transmission of data (parameters, detailed diagnostic information, commissioning data, I&M data)
An application relation (AR) is formed between an IO Controller and an IO Device. The communication view determines the communication relationships, the diagnostic options and the potential useful data exchange. Communication relationships (CR) with varying properties are specified for the transfer of parameters, cyclic data exchange and alarm handling based on this AR.
Communication channels are set up to handle the data exchange between each IO Controller and the IO Device. It is possible to form more than one application relationship between different devices. Isochronous drive controls can be implemented with PROFINET IO and the PROFIdrive profile for motion control applications.
In the GSD file, the device manufacturer must exactly describe how the device functions are specifically mapped to the PROFINET IO model, i.e. the properties of the IO device. GSDML (GSD Markup Language), an XML-based language, is used for this purpose. The GSD file is read in by the engineering tool and forms the basis for planning the configuration of a PROFINET IO system.
|
