Siemens SIMATIC ET 200M Operating Instructions Manual page 234

Technical Specifications
10.4 Technical specifications of the IM 153-4 PN interface module
• Data records for I/O modules
• From 6ES7153-4AA01-0XB0;
– Isochronous real-time communication
– Minimum update time 250 μs with IRT
– Prioritized startup
– Device replacement without removable medium/programming device
– Changing IO devices during operation (changing partner port)
Isochronous real-time communication
Synchronized transmission method for the cyclic exchange of IRT data between PROFINET
devices.
A reserved bandwidth is available within the send clock for IRT IO data. The reserved
bandwidth ensures that IRT data can be transferred at reserved synchronized intervals,
without being influenced by other higher network loads (e.g. TCP/IP communication, or
additional real-time communication).
The IRT option "high flexibility" allows maximum flexibility. Topological configuration is not
required.
You can find additional information in the STEP 7 online help and the "PROFINET System
Description (http://support.automation.siemens.com/WW/view/en/19292127)" manual.
Prioritized startup
Prioritized startup denotes PROFINET functionality for accelerating the startup of IO devices in
a PROFINET IO system with RT and IRT communication.
The function reduces the time that the correspondingly configured IO devices require to
return to the cyclic user data exchange in the following cases:
• After the power supply has returned
• After a station has returned
• after activation of IO devices
Note
The ramp-up time depends on the number and type of modules. Additionally, note that when
using the active backplane bus, the minimum ramp-up time increases by 1.5 seconds.
You can find additional information in the STEP 7 online help and the "PROFINET System
Description (http://support.automation.siemens.com/WW/view/en/19292127)" manual.
234
Operating Instructions, 04/2022, EWA-4NEB7806006-09
ET 200M