Properties And Advantages Of The I-Device; Characteristics Of An I-Device - Siemens S7-1200 System Manual

Communication
10.2 PROFINET
10.2.7.2

Properties and advantages of the I-device

Fields of application
Fields of application of the I-device:
● Distributed processing:
A complex automation task can be divided into smaller units/subprocesses. This results
in manageable processes which lead to simplified subtasks.
● Separating subprocesses:
Complicated, widely distributed and extensive processes can be subdivided into several
subprocesses with manageable interfaces by using I-devices. These subprocesses can
be stored in individual STEP 7 projects if necessary, which can later be merged to form
one master project.
● Know-how protection:
Components can only be delivered with a GSD file for the I-device interface description
instead of with a STEP 7 project. The user can protect his program since it no longer has
to be published.
Properties
Properties of the I-device:
● Unlinking STEP 7 projects:
Creators and users of an I-device can have completely separated STEP 7 automation
projects. The GSD file forms the interface between the STEP 7 projects. This allows a link
to standard IO controllers through a standardized interface.
● Real-time communication:
The I-device is provided with a deterministic PROFINET IO system through a
PROFINET IO interface and therefore supports RT (real-time communication) and IRT
(isochronous real time).
Advantages
The I-device has the following advantages:
● Simple linking of IO controllers
● Real-time communication between IO controllers
● Relieving the IO controller by distributing the computing capacity to I-devices.
● Lower communications load by processing process data locally.
● Manageable, due to processing of subtasks in separate STEP 7 projects
10.2.7.3

Characteristics of an I-device

An I-device is included in an IO system like a standard IO device.
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S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG