Chapter 4. PROFINET System Operation
GFK-2571N
May 2018
87
4.1.1
PROFINET Communications
Communications on a PACSystems PROFINET network use the standard PROFINET communications described
in this section.
4.1.1.1
Application Relationships
Before an PACSystems PROFINET IO-Controller can exchange data with a PROFINET IO-Device, an Application
Relationship (connection) must be established between the devices. The PACSystems PROFINET IO-Controller
automatically sets up the correct number and types of Application Relationship and Communication
Relationship channels (see below) based on its Proficy Machine Edition configuration. Usually, only one
Application Relationship is established per IO-Device.
Communication Relationships within an Application Relationship
Within each Application Relationship, the PACSystems PROFINET IO-Controller establishes the following types
of Communication Relationships (CRs):
•
Record Data CRs
–
always the first to be established within an Application Relationship. Record Data
Communication Relationships are used for non-real-time transfers of data records such as startup
parameter data, diagnostics data, identification data, and configuration data.
•
IO CRs
–
used for the real-time, cyclic transfer of I/O data
•
Alarm CR
–
used for real-time, acyclic transfer of alarms and events
Figure 89 represents an Application Relationship between a PACSystems controller with a PNC001 module and
an IO-Device. In the example below, the IO-Device consists of a VersaMax PNS with VersaMax I/O modules, but
the same principles apply for all IO-Controllers and IO-Devices.
Figure 89: Application Relationship