3Com SuperStack 4, Configuration Manual

Page: 63 / 432

4
P
OWER OVER
E
THERNET
(P
O
E)
C
ONFIGURATION
This chapter covers the following topics:
■
PoE Overview
■
PoE Configuration
PoE Overview
The Switch 5500G-EI 24 Port PWR and Switch 5500G-EI 48 Port PWR support
Power over Ethernet (PoE). This feature uses twisted pairs to provide -44 through
-62 VDC power to remote powered devices (PDs), such as IP Phones, WLAN APs,
Network Cameras, and so on. The PWR switches provide the following
capabilities:
z
Power sourcing equipment (PSE), the PWR switches support the IEEE802.3af
standard and can also supply power to part of the PDs non-compliant with the
standard.
z
The PWR switches can deliver data and current in the mean time through data
wires (1, 3, 2, and 6) of the category-3/5 twisted pairs.
z
Through its 24/48 Ethernet electrical ports, the PWR switches can supply power
to up to 24/48 remote Ethernet switches with the maximum distance of 100 m
(328 feet).
z
Each Ethernet port can supply at most 15400 mW of power to a PD.
z
When AC power input is adopted for the switch: the maximum total power
that can be provided by the PWR switches is 300 W. These switches can determine
whether to supply power to the next remote PD it detected depending on the
total power.
z
When DC power input is adopted for the switch: the PWR switches are
capable of supplying full power to all of the 24/48 ports.
z
The PSE processing software on the PWR switches can be upgraded online.
z
The PWR switches provides statistics about power supplying on each port and
the whole equipment, which you can query through the
display
command.
z
The PWR switches provide two modes (
auto
and
manual
) to manage the power
feeding to ports in the case of PSE power overload.
z
The PWR switches provide overheat protection mechanism. This stops the
power feeding to any PD connected with a port when the ambient temperature
reaches 65
0
C; and restores the power feeding to all the PDs connected with the
ports when the temperature drops below 60 0 C.