Description of the device
4.3 Interfaces and signaling contact of the switches
SCALANCE X-300
Operating Instructions, 05/2016, A5E01113043-20
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Two communication modes are possible:
●
Half duplex
Two-way alternate transmission mode - it is only possible to either send or receive over
the interfaces at any one time.
●
Full duplex mode
Two-way simultaneous - both communication partners can send and receive at the same
time.
Transmission medium
Data is transmitted over an eight-wire twisted pair cable.
Note
For data transmission at 1 Gbps, at least a Cat 5e twisted-pair cable with 4 x 2 wires is
necessary. With a four-wire cable (2 x 2 wires), a maximum data transmission rate of 100
Mbps is possible.
Transmission range
The maximum transmission range (segment length) is 100 m.
Connectors
The connectors used are 8-pin RJ-45 jacks.
4.3.1.3
Power over Ethernet (PoE)
Power over Ethernet (PoE)
With PoE, the power for networked devices is carried via Ethernet. Here, there are two
methods of supplying power:
●
Alternative A
Here, the voltage is transferred on the data wires 1, 2, 3 and 6 of the Ethernet cable
Requirements for the Ethernet cable:
–
For 10Base-T/100Base-TX, a 4-wire cable is adequate for data transmission and
power supply.
–
With 1000BASE-T, an 8-wire cable is necessary for data transmission.
●
Alternative B
Power is transferred on the free wires 4, 5, 7 and 8 of the Ethernet cable.
Requirements for the Ethernet cable: For 10Base-T/100Base-TX/1000BASE-T, an 8-wire
cable is needed.