Siemens SINAMICS S150 NEMA, Operating Instructions Manual

Page: 369 / 862

Operation
6.9 Communication via PROFINET IO
Enclosed Drives
Operating Instructions, 12/2018, A5E36652151A
367
Cyclic communication using PROFINET IO with IRT or using RT is possible for all drive units
equipped with a PROFINET interface. This means that error-free communication using other
standard protocols is guaranteed within the same network.
Note
CU320-2 DP and inserted CBE20
The cyclic process data channel for PROFIBUS DP is initially deactivated for a CU320-2 DP
and inserted CBE20. However, it can be reactivated with parameter p8839 = 1 at any time
(see Chapter "Parallel operation of communication interfaces (Page 433)").
References
Note
PROFINET for drive technology is standardized and described in the following document:
•
PROFIBUS profile PROFIdrive – Profile Drive Technology
Version V4.2, October 2015
PROFIBUS User Organization e. V.
Haid-und-Neu-Strasse 7, D-76131 Karlsruhe, Germany
http://www.profibus.com, Order Number 3.172
• IEC 61800-7
6.9.2.2 Real-time (RT) and isochronous real-time (IRT) communication
Real-time communication
When communication takes place via TCP/IP, the resultant transmission times may be too
long and not defined to meet the production automation requirements. When communicating
time-critical IO user data, PROFINET IO therefore uses its own real-time channel, rather
than TCP/IP.
Real time means that a system processes external events over a defined period.
Determinism
Determinism means that a system will react in a predictable ("deterministic") manner.
With PROFINET IO with IRT, it is possible to precisely determine (predict) transmission
times.
PROFINET IO with RT (Real Time)
Real-time data is treated with a higher priority than TCP(UDP)/IP data. Transmission of time-
critical data takes place at guaranteed time intervals. RT communication is the basis for data
exchange using PROFINET IO.