3Com Switch 7750 Configuration Guide Guide

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POE CONFIGURATION
PoE Overview
Introduction to PoE Power over Ethernet (PoE) uses 10BaseT, 100Base-TX, and 1000Base-T twisted
pairs to supply power to the remote powered devices (PD) in the network and
implement power supply and data transmission simultaneously.
Advantages of PoE
■ Reliability: The centralized power supply provides backup convenience, unified
management, and safety.
■ Easy connection: Network terminals only require an Ethernet cable, but no
external power supply.
■ Standard: PoE conforms to the 802.3af standard and uses a globally uniform
power interfaces;
■ Bright application prospect: PoE can be applied to IP phones, wireless access
points (APs), chargers for portable devices, card readers, cameras, and data
collection.
PoE components
■ Power sourcing equipment (PSE): PSE is comprised of the power and the PSE
functional module. It can implement PD detection, PD power information
collection, PoE, power supply monitoring, and power-off for devices.
■ PD: PDs receive power from the PSE. PDs include standard PDs and
nonstandard PDs. Standard PDs conform to the 802.3af standard, including IP
phones, WLAN APs, network cameras and so on.
■ Power interface (PI): PIs are RJ45 interfaces which connect PSE/PDs to network
cables.
PoE Features Supported
by Switch 7750 Family
The Switch 7750 Family supports PoE. Equipped with external power supply and
PoE-enabled boards, the Switch 7750 Family can provide -48 VDC power to
remote powered devices (PDs) through twisted pairs.
■ The Switch 7750 Family supports IEEE802.3af standard. While it can also
supply power to PDs noncompliant with the standard.
■ The power supply of the Switch 7750 Family is administered by the main
control board; each PoE board on the switch can be viewed as a power
sourcing equipment (PSE) and administers the power supply of all the ports on
it independently.
■ The Switch 7750 Family can deliver data and current simultaneously through
data wires (1, 3, 2, and 6) of category-3/5 twisted pairs.