3Com 3C10220 manual Overview, Power source is designed for use with a standard

10CHAPTER 1: 3COM ETHERNET POWER SOURCE OVERVIEW

Overview	The power source is designed for use with a standard
	10BASE-T/100BASE-TX Ethernet network over standard TIA/EIA-568,
	Category 5 cable. The DC operating power for the data terminal units is
	fed through the unused pairs (7/8) and (4/5).

You can order the EPS in either of these models:

■12 Ethernet ports

■24 Ethernet ports

Features The EPS has the following hardware features:

■Remote power feeding of Ethernet terminals

■12 or 24 ports of combined 10BASE-T/100 BASE-TX data and power

■Shielded RJ-45 input/output connectors

■Universal 85-264VAC 50/60Hz input

■Power feeding over 7/8 and 4/5 spare twisted pairs of Category 5 UTP/STP cable

■Independent overload and short-circuit protection for each port

■Port status LED indicators

■Power on/off command for each port

■RS-232 monitoring and control serial port

■FLASH memory for field firmware upgrades

■Standard 19” 1.5U rack mounting with hardware

■–24 VDC connector for an external DC power supply