3Com 3CNJPSE24 - Manual (Page 9)

Introduction to the Ethernet Power Supply
Ethernet Power Supply User s Guide 1-1
Introduction to the
Ethernet Power Supply
This chapter contains introductory information about the
Ethernet Power Supply and how it can be used in your network.
It covers the following topics:
- About the Ethernet Power Supply
- Ethernet Power Supply Front View Detail
- Ethernet Power Supply Rear View Detail
- Network Configuration Examples
About the Ethernet Power Supply
The Ethernet Power Supply is a 24-port Ethernet-channel, 48V-
power-feeding device. This device is designed for use with a
10/100BASE-TX standard Ethernet network over a standard
TIA/EIA-568 Category 5 cabling plant. The DC operating power
for the data terminal units is fed through the unused pairs (7/8
and 4/5).
The Ethernet Power Supply normally powers devices that are
enabled for Power Over LAN or are equipped to receive power
over Ethernet. These devices are called Powered Data
Terminal Equipment (PDTE). Devices that are not equipped to
receive power over Ethernet require local power or an external
splitter to be powered by the Ethernet Power Supply.
NOTE: The Ethernet Power Supply is not a data hub or switch;
it is a power distribution device to be used in conjunction with a
data hub or switch. The Ethernet Power Supply adds power to
unused wires and passes through data from the ports on an
Ethernet or Fast Ethernet hub or switch using standard 8-wire,
category 5 cables. Do not use crossover cables.
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