3Com 4200G Series, Руководство по началу работы

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Connecting a Redundant Power Supply 33
RPS LED The RPS status LED on the front of the Switch 4200G indicates the status
of the RPS and AC supplies as shown in Table 9.
Table 9 RPS LED Colors
Using Power over
Ethernet
The Switch 4200G Power over Ethernet (PoE) units can supply power to
any IEEE 802.3af compliant device through any of its front panel ports
over a Category 5 or Category 5e Ethernet cable. The same cable
connects the device to the network.
The Switch 4200G units can supply power through the 10/100 ports only.
Power over Ethernet is a self-configuring protocol. When you plug a PoE
compliant device into one of the ports on the switch, the switch supplies
the power required to the device, providing that the total power budget
for the switch is not exceeded.
A PoE switch combines the functionality of a standard Ethernet switch
with a single power supply that can power multiple devices. Using a PoE
switch has the following advantages over an non-powered network.
■
Reduced Cabling — a PoE (802.3af) compliant device that has its
power supplied over its Ethernet cable does not require a separate
power supply. If, for example, you use the switch to connect a 3Com
11 Mbps Wireless LAN Access Point 8500 to the network, then only a
network cable is required to provide both power and network
connectivity.
■
Increased Reliability — a device powered by a PoE switch can take
advantage of the facilities available to the switch. You can fit the
switch with a redundant power supply or uninterruptible power
supply to increase its uptime.
The switch supports resistor detection according to IEEE 802.3af and
pre-standard detection methods.
Color State
Green The AC and RPS supply is connected.
Yellow The AC supply has failed or is not connected. The RPS
supply is connected.
Off There is no RPS supply connected.
10014914_AB_Switch 4200G.book Page 33 Tuesday, October 2, 2007 12:13 PM