Siemens SIMATIC SCALANCE X-300M PoE, Краткое руководство по эксплуатации

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Column 1 2 3 4
Port number - P1 (gigabit Ethernet) P5 (gigabit multimode fiber-
optic cable, SC ports)
P7
(interface depends on SFP
used)
- P2 (gigabit Ethernet)
- P3 (gigabit Ethernet) P6 (gigabit multimode fiber-
optic cable, SC ports)
P8(interface depends on SFP
used)
- P4 (gigabit Ethernet)
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.
PoE-compliant devices can be divided into the following groups:
● PSE - power sourcing equipment
These inject power onto the Ethernet cable.
● PD - powered devices
These are supplied with power via Ethernet.
PoE ports of SCALANCE X‑300M PoE switches
As a PSE, the PoE switch supplies PoE-capable devices with power over Ethernet. The 48 V
power required to supply the powered devices is generated internally on the switch, no extra
power supply unit is necessary.
The PoE switch uses "alternative A" for this. Per RJ-45 port, a maximum of 15.4 W are available
for supplying a PoE-compliant device. If a Cat5/Cat5e cable with a maximum length of 100 m
is used, the connected device can be supplied with a power of 12.95 W.
Note
The total power provided by the switch on all four PoE ports is a maximum of 30.8 W.
The PoE ports meet the conditions listed in the IEEE 802.3af / IEEE 802.3at standard (type 1)
for environment A , in other words power supply over Ethernet within a power supply system.
For details of configuring and enabling PoE for individual ports, refer to the configuration
manual SCALANCE X-300 / X-400 on the accompanying CD.
Device description
4.2 Product properties and device views
SCALANCE X-300M PoE
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Compact Operating Instructions, 11/2019, A5E02630810-13