Isochronous Real-Time Communication - Siemens SIMATIC ET 200eco PN Operating Instructions Manual

4.5

Isochronous real-time communication

Isochronous real-time communication
Synchronized communication protocol for cyclic exchange of IRT data between PROFINET
devices. A reserved bandwidth is available within the send cycle for IRT IO data. The
reserved bandwidth ensures that the IRT data are transmitted at reserved, synchronized
intervals while remaining uninfluenced by another greater network load (for example, TCP/IP
communication or additional realtime communication).
● "High performance" IRT option (not for 6ES7148-6JA00-0AB0 IO-Link Master):
Topological configuration is required (STEP 7 V5.5 or higher).
Note
When using the IO controller as a Sync-Master for IRT communication with the "high
performance" IRT option, the following must be observed:
Operate the IO controller as a Sync-Master if you configure the IRT communication with
the "high performance" option.
Otherwise, IRT and RT configured IO devices may fail if the sync master fails.
Note
Using redundant Sync-Master
When using redundant Sync-Masters, a short-term failure of the 6ES7148-6JD00-0AB0
IO-Link Master can occur during the switching of the Sync-Master.
Detailed information
For additional information, refer to the SIMATIC PROFINET system description
(http://support.automation.siemens.com/WW/view/en/19292127) System Manual and the
Migration from PROFIBUS DP to PROFINET IO
(http://support.automation.siemens.com/WW/view/en/19289930) Programming Manual.
ET 200eco PN
Operating Instructions, 08/2016, A5E01250250-AJ
4.5 Isochronous real-time communication
Configuring
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