Description
User manual 55170_hdb_en_13
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3.2.2
Structure of the conformance classes
Structure
The scope of functions of PROFINET IO is clearly classified in "Conformance
Classes" (CC). These classes give a clear overview of the various minimum
properties. There are three conformance classes:
Fig. 3-1: Structure of the conformance classes
CC-A
CC-A
offers basic functions for PROFINET IO with RT communication. Typical
cycle time starting from 2 ms. In this case, unmanaged switches can also be
used. Wireless communication is possible only in this class. All IMPACT67
conform to class
CC-A
.
The TREE unmanaged switches by MURRELEKTRONIK can be used as
switches.
CC-B
CC-B
expands the concept by the inclusion of network diagnostics and topol-
ogy information. Cycle time typically from 2 ms. The topology information and
projected device names enable easy device exchange. The defective device
can be easily exchanged for a new device with factory settings. All IMPACT67
conform to class
CC-B
.
CC-C
CC-C
describes the basic functions for devices with hardware-supported
bandwidth reservation and synchronization (RT communication) and therefore
forms the basis for isochronous applications. The implementation of Isochro-
nous Real Time (IRT) in Ethernet controllers makes it possible to reach update
times of 31.25μs and a jitter accuracy of less than 1μs.
