Structure of the CPU 410-5H
3.5 PROFINET IO interface (X5, X8)
CPU 410-5H Process Automation/CPU 410 SMART
System Manual, 10/2013, A5E32631667-AA
43
Note
Networking of PROFINET IO components
The PROFINET IO interfaces of our devices are set to "automatic setting" (autonegotiation)
by default. Verify that all devices connected to the PROFINET IO interface of the
CPU are
also set to the "Autonegotiation" mode. This is the default setting of standard PROFINET
IO/Ethernet components.
If you connect a device to the PROFINET IO interface of the CPU that does not support the
"automatic setting" (Autonegotiation) operat
ing mode or you choose a setting other than the
"automatic setting" (Autonegotiation) for this device, note the following:
PROFINET IO requires 100 Mbps full-duplex operation, which means if the PROFINET
IO interface of the CPU is used simultaneously for PROFINET IO communication and
Ethernet communication, operation of the PROFINET IO interface is permissible only in
100 Mbps full-duplex mode.
If the PROFINET IO interface(s) of the CPU are used for Ethernet communication only,
100 Mbps full-duplex mode is possible. Half-duplex mode is not allowed in any situation.
Background: If a switch that is permanently set to 10
Mbps half-duplex is connected to the
interface of the CPU, the "Autonegotiation" setting forces the CPU to adapt itself to the
settings of the
partner device, i.e., the communication operates de facto at "10 Mbps half-
duplex". However, this would not be a valid operating mode because PROFINET IO
demands operation at 100
Mbps full-duplex.
● For details about PROFINET, refer to PROFINET System Description
(http://support.automation.siemens.com/WW/view/en/19292127)
● For detailed information about Ethernet networks, network configuration and network
components refer to SIMATIC NET Manual: Twisted-Pair and Fiber-Optic Networks
(http://support.automation.siemens.com/WW/view/en/8763736).
● For additional information about PROFINET IO, refer to: PROFINET
(http://www.profibus.com/)