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Connecting a Redundant Power Supply 39
RPS LED The RPS status LED on the front of the Switch 5500 indicates the status of
the RPS and AC supplies as shown in
Table 12 .
Table 12 RPS LED Colors
Using Power over
Ethernet
The Switch 5500G-EI 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 5500 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 will
supply the power required to the device, providing that the total power
budget for the Switch would not be exceeded by doing so.
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 unpowered network:
■
Reduced Cabling — a PoE (802.3af) compliant device which has its
power supplied over its ethernet cable does not require a separate
power supply. If, for example, the Switch is used 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 will be
able to take advantage of the facilities available to the Switch. The
Switch can be fitted with a redundant power supply or uninterruptible
power supply, increasing its uptime.
The Switch supports resistor detection according to IEEE 802.3af and
pre-standard detection methods.
Color State
Green AC and RPS supply connected.
Yellow AC failed or not connected. RPS supply is ok.
Off There is no RPS supply connected.