Siemens CP 343-1 - Influence of MPI on Connections Via Industrial Ethernet; Profinet Io; How PROFINET IO Devices Start up in a Large Configuration; PROFINET IO When Operating Other Services at the same Time

Configuration and operation
6.5 Influence of MPI on connections via Industrial Ethernet
CP 343-1
Manual, 12/2018, C79000−G8976−C201-08
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6.5
Influence of MPI on connections via Industrial Ethernet
Adding/removing MPI nodes
If a station on the MPI bus is added or removed, for example because a service PG has
been connected or disconnected, it is possible that active communication connections on the
communications bus are aborted. This has the following effects on the communication
connections on Industrial Ethernet:
● All S7 connections are temporarily aborted.
Exceptions: This does not apply when using CPUs with a separate communication bus,
for example:
CPU 318-2, CPU 317-2 PN/DP, CPU 319-3 PN/DP, CPU 315-2 PN/DP,
CPU 315F-2 PN/DP, CPU 317-2 DP, CPU 317T-2 DP, CPU 317F-2 DP,
CPU 317F-2 PN/DP, CPU 319-3 PN/DP
● FETCH/WRITE connections are temporarily aborted.
On the FC interface in the user program, the condition codes made up of the DONE,
ERROR and STATUS parameters must be evaluated in FC11 / FC12.
6.6
PROFINET IO
6.6.1
How PROFINET IO devices start up in a large configuration
When operating the module with a large configuration (up to 32 communications connections
and up to 32 PROFINET IO devices), it may take several minutes when the station starts up
before all PROFINET IO devices have received configuration data from the PROFINET IO
controller. The IE/PB Link PN IO operating as a PROFINET IO device is particularly affected
by this.
To ensure that the CPU does not interrupt the distribution of project engineering data in this
situation, the monitoring times may need to be increased on the CPU (Properties dialog,
"Startup" tab).
6.6.2
PROFINET IO when operating other services at the same time
Sporadically used services
Note the following if you are using functions alongside PROFINET IO that affect the
configuration or the operating status (FB55, Primary Setup Tool, STEP 7, NCM Diagnostics):
Note
The functions listed above can influence the flow in PROFINET IO so that
an interruption of
cyclic IO data exchange of the PROFINET IO devices lasting several seconds may occur.