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  • Manual... 
  • PoE+ Gigabit Managed Switch Eco CLI Guide
    CLI Guide for the LPB2810A, LPB2826A, and LPB2848A (Version 1)
 
  • Manual... 
  • PoE L2 Managed Gigabit Switch with 1000BASE-TX Ports, Dual-Media RJ-45/SFP Ports User Manual
    User Manual for PoE L2 Managed Gigabit Switch with 1000BASE-TX Ports, Dual-Media RJ-45/SFP Ports (2)
 
  • Application Note... 
  • Black Box Multicast Video-over-IP Solution
    MediaCento IPX and LGB Series Ethernet Switches (Version 1)
 
  • Manual... 
  • -Port PoE PD Switch (Unmanaged, 10BASE-T/100BASE-TX) Manual
    Manual for the LPE108AE (Version 1)
 

Black Box Explains...PoE phantom power.

10BASE-T and 100BASE-TX Ethernet use only two pairs of wire in 4-pair CAT5/CAT5e/CAT6 cable, leaving the other two pairs free to transmit power for Power over Ethernet (PoE) applications. However,... more/see it nowGigabit Ethernet or 1000BASE-T uses all four pairs of wires, leaving no pairs free for power. So how can PoE work over Gigabit Ethernet?

The answer is through the use of phantom power—power sent over the same wire pairs used for data. When the same pair is used for both power and data, the power and data transmissions don’t interfere with each other. Because electricity and data function at opposite ends of the frequency spectrum, they can travel over the same cable. Electricity has a low frequency of 60 Hz or less, and data transmissions have frequencies that can range from 10 million to 100 million Hz.

10- and 100-Mbps PoE may also use phantom power. The 802.3af PoE standard for use with 10BASE-T and 100BASE-TX defines two methods of power transmission. In one method, called Alternative A, power and data are sent over the same pair. In the other method, called Alternative B, two wire pairs are used to transmit data, and the remaining two pairs are used for power. That there are two different PoE power-transmission schemes isn’t obvious to the casual user because PoE Powered Devices (PDs) are made to accept power in either format. collapse

  • Manual... 
  • Unmanaged 802.3at PoE Ethernet Switch (16-Port) User Manual
    User Manual for the Unmanaged 802.3at PoE Ethernet Switch (16-Port) (Version 2)
 

Product Data Sheets (pdf)...LPH1000 Series Hardened Ethernet Switch—(4) 10/100/1000 Mbps, (1) GE SFP


Product Data Sheets (pdf)...Managed Fiber Switches

  • Manual... 
  • PoE+ Gigabit Managed Switch Eco User Manual
    User Manual for the LPB2810A, LPB2826A, and LPB2848A (Version 1)
 
  • Manual... 
  • SFP Gigabit/10-Gigabit Managed Switch Eco (28-Port) User Manual
    User Manual for the LGB5128A (Version 1)
 
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