Manual – MOVI-PLC® advanced DHE41B/DHF41B/DHR41B Controller
45
4
Installing the MOVI-PLC® advanced DHR41B controller
Mounting/Installation Instructions
4.5.10 The integrated Ethernet switch
You can use the integrated Ethernet switch to achieve line topologies known from the
fieldbus technology. Other bus topologies, such as star or tree, are also possible. Ring
topologies are not supported.
Autocrossing:
The two ports leading out of the Ethernet switch have autocrossing functionality. This
means you can use patch or cross-over cables to connect the next Ethernet node.
Autonegotiation
The baud rate and the duplex mode is negotiated by both Ethernet nodes when estab-
lishing the connection. The two Ethernet ports of the EtherNet/IP interface support au-
tonegotiation functionality and operate at a baud rate of 100 Mbit or 10 Mbit in full duplex
or half duplex mode.
Notes on multi-
cast handling
• The integrated Ethernet switch does not provide a filter function for Ethernet multi-
cast telegrams. Multicast telegrams that are usually sent from the adapters
(DHR41B) to the scanners (PLC) are passed on to all switch ports.
• IGMP snooping (managed switch) is not supported.
• SEW-EURODRIVE recommends to connect DHR41B only with network components
that support IGMP Snooping (e. g. managed switch) or in which protective measures
against excessive multicast load are integrated (e. g. units from SEW-EURODRIVE).
When using units that do not possess this function, the high load on the network can
cause faults.
NOTE
The number of industrial Ethernet switches connected to the line affects the telegram
runtime. If a telegram passes through the units, the telegram runtime is delayed by the
Store & Forward function of the Ethernet switch:
• For a telegram length of 64 Byte by approximately 10 µs (at 100 Mbit/s)
• For a telegram length of 1500 Byte by approximately 130 µs (at 100/Mbit/s)
This means that the more units a telegram has to pass through, the higher the telegram
runtime is.
