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PoE Solutions PoE Midspans, Adapters, Power Over Ethernet

PoE Power-on-demand products

With power-on-demand midspans, you will achieve full power on every port, gain support for both the legacy PoE standard IEEE 802.3af and the higher-power IEEE 802.3at standard while providing greater flexibility for 75% less than the cost of replacing your business-class switch.

15.4W/port, IEEE802.3af
The current standard for Power-over-Ethernet, was formally approved in 2003, defining PoE applications requiring up to 12.95W of power. With this specification, users were no longer locked into one brand of equipment and experienced fewer equipment problems and hazardous situations caused by non-compliant products. The standard facilitates interoperability, ensures power application only where appropriate, and mandates safety precautions and protection against faults in an installation.

Download a copy of the IEEE 802.3af standard

Key features of IEEE 802.3af standard

  • Designed to work on networks with existing CAT5/CAT6 and above structured cabling systems using RJ45 connections
  • Power Sourcing Equipment (PSE) can be an endspan (Ethernet switch with powered ports) or a midspan
  • Neither endspan or midspan produces any interference with the data transmission signals
  • The endspan or midspan can provide 15.4 watts per port (or link). Due to line loss, the effective wattage available to the powered device (PD) is 12.95 watts
  • It does not matter if a PD receives the PoE signals from an endspan or midspan source. It must receive power through its RJ45.
  • PoE operation conforms to Standard 802.3 Ethernet Cabling distances (100 meters max per port)

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30W/port, IEEE802.3at (PoE Plus)
For devices with higher power requirements, like PTZ, PTZ dome and heated outdoor cameras, a new standard IEEE802.3at (PoE Plus) is under development and expected to be ratified in 2009. PoE Plus is a proposal to increase the available power from Ethernet cables from the current 15.4W per port to a level targeted at least 45W. The current specification allows 44-57V at 350mA maximum on a single pair of conductors and a maximum 15.4W.

Even though multiple pairs are available and wires are rated as high as 860mA many issues are being investigated ensure that the increased power can be done safety and without interfering with the data.
There are midspans and splitters that already conform to the IEEE 802.3at pre-standard for powering devices with high power requirements on a network.

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60W/port, 80W/port, 120W/port
Even before the PoE Plus standard is approved, users are demanding applications that require more than 30W of power per port, such as computer workstations, LCD display panels, and WAP arrays. Other emerging applications, including emergency lighting, security system sensors, and even medical monitoring, will greatly benefit from combining data and centralized backup power.


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