4.2
Industrial Ethernet
4.2.1
Electrical
Note
Strain relief for the Ethernet cables
In order to avoid mechanical stress on the Ethernet cables and resulting interruption of the
contact, fasten the cables at a short distance from the connector using a cable guide or busbar.
R-45 connector technology
The attachment to Industrial Ethernet uses RJ-45 connected technology with MDI-X assignment.
Pin assignment
The following table shows the pin assignment of the R-45 connectors.
Pin number
Assignment
R-45 connector
10/100 Mbps
10/100/1000 Mbps
Pin 1
RD+
D1+
Pin 2
RD-
D1-
Pin 3
TD+
D2+
Pin 4
n. c. (Not connected)
D3+
Pin 5
n. c. (Not connected)
D3-
Pin 6
TD-
D2-
Pin 7
n. c. (Not connected)
D4+
Pin 8
n. c. (Not connected)
D4-
MDI / MDI-X autocrossover
With the MPI/MDI-X autocrossover function, the send and receive contacts of an Ethernet port
are assigned automatically. The assignment depends on the cable with which the
communications partner is connected. This means that it does not matter whether the port is
connected using a patch cable or crossover cable. This prevents malfunctions resulting from
mismatching send and receive wires. This makes installation much easier for the user.
Note
Formation of loops
Please note that the direct connection of two ports on the IE switch or accidental connection
over several IE switches causes an illegal loop. Such a loop can lead to network overload and
network failures.
Connecting up
4.2 Industrial Ethernet
SCALANCE XR-100WG
Operating Instructions, 09/2020, C79000-G8976-C455-04
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